Endometriosis: why the diagnosis usually takes years
A median of 10.4 years between the first symptoms and the diagnosis. 74 percent with at least one wrong explanation before that. This article shows where that comes from, what ultrasound and MRI can do, and why a laparoscopy has no longer been strictly required for the diagnosis since 2022.
You are sitting in the waiting room, rehearsing a sentence in your head. Not too dramatic, or it will sound hysterical. Not too quiet, or it will be missed. You have said this sentence many times, in different practices, over years. And every time you felt slightly worse afterwards, because you took home the feeling of making too much fuss about something everyone has.
Many women know this pattern. It has a name and a number. In a questionnaire study at tertiary centres in Austria and Germany, a median of 10.4 years lay between the first symptoms and the endometriosis diagnosis. 74 percent of the 171 women surveyed had received at least one wrong diagnosis before that [Real-World, survey, human].
Ten years. That is not an outlier, that is the middle.
And the most important sentence right at the start: this delay is not a personal failure. It is also not anyone's malice. It comes out of a chain of reasons that can be named, and a few of them have genuinely changed in recent years.
If you have been told for ten years that your pain is normal, at some point you believe it. The problem is not the pain, it is the explanation that was found too early. And the explanation is easier to find when you know what you are looking for.
Some situations do not wait for a pattern across three cycles. They belong in prompt medical assessment:
- sudden, severe, one-sided lower abdominal pain
- pain with fever
- circulatory problems, dizziness, collapse, cold sweat
- very heavy or suddenly changed bleeding
- any bleeding after the menopause
- blood in the stool or in the urine
- unintended weight loss
- visual disturbances or headaches together with milk discharge from the breast
This is not a list to panic over. It is a shortcut. If one of these applies to you, you skip the patient observing and have it looked at promptly.
What this article covers
- How long it really takes, and why three studies give three numbers
- Why severe period pain slips through culturally
- The symptoms outside the period
- Why a normal ultrasound rules nothing out
- What a practised examiner does differently
- When an MRI makes sense
- Diagnosis without laparoscopy, since ESHRE 2022
- CA-125, saliva tests and why there is no blood test
- Endometriosis centres and what you bring along
All the numbers in this text come from studies in humans or from guidelines. Where a number comes from a survey, that is stated, because a survey measures something different from a cohort. And where the data are thin, I say so.
Ten years is not a rare case, it is the middle
There is a moment that many women with endometriosis describe. Not the moment of the diagnosis. The moment afterwards, when they count backwards. When did this actually start. And then a number comes out that frightens them, because it is measured in years and not in months.
This number is well studied. And at the same time it is hard to compare, because different papers measure different things. So I put them side by side and not on top of each other.
A team around Hudelist surveyed 171 women with histologically confirmed endometriosis at tertiary centres in Austria and Germany between September 2010 and February 2012.
The median interval from the first appearance of symptoms to the diagnosis was 10.4 years, with a standard deviation of 7.9 years. 74 percent had received at least one wrong diagnosis before that. Three factors went along with a longer delay: a previous misdiagnosis, a mother who rated menstruation as a negative event, and classifying one's own period pain as normal.
For you that means: if you had the feeling of settling into an explanation that did not fit, you were not alone in that. The authors themselves point out that only operated patients were included, so the group was preselected.
Hudelist G, Fritzer N, Thomas A et al. Human Reproduction 2012;27(12):3412-3416. DOI: 10.1093/humrep/des316 · PMID: 22990516 [Real-World, survey, human]Requadt and colleagues surveyed 2017 people with endometriosis from 63 countries through patient-led online groups and separated two stretches of the path from each other.
Between symptom onset and the first medical appointment lay an average of 3.7 years. Between that first appointment and the diagnosis lay 5.8 years. Together 9.6 years. Participants over 35 years reported a longer time to diagnosis than 18 to 24 year olds, on average 10.7 years against 6.8 years.
For you that means: the delay has two halves. You can influence the first one by going earlier and naming more clearly what is going on. You cannot influence the second one, and you do not have to feel responsible for it either.
Requadt E, Nahlik AJ, Jacobsen A, Ross WT. BJOG 2024;131(7):941-951. DOI: 10.1111/1471-0528.17719 · PMID: 37961031 [Real-World, survey, human]A group at the Berlin Center for Epidemiology and Health Research systematically searched for publications from 2018 onwards reporting the time to endometriosis diagnosis and included 17 observational studies.
The reported times to diagnosis lay between 0.3 and 12 years, depending on whether total, primary or clinical delay was measured, in which country and in which group. The quality of the evidence ranged from poor to good. The conclusion: the delay persists, and it arises predominantly on the medical side.
For you that means: if you come across three different numbers online, none of them is wrong. They measure different stretches.
De Corte P, Klinghardt M, von Stockum S, Heinemann K. BJOG 2025;132(2):118-130. DOI: 10.1111/1471-0528.17973 · PMID: 39373298 [Systematic Review]These three numbers must not be added up. A median of 10.4 years from an operated group in Austria and Germany, a mean of 9.6 years from an international patient-group survey, and a range of 0.3 to 12 years from 17 heterogeneous studies are three different measurements. What they have in common is the direction.
And now the part that is rarely told, because it does not provoke outrage: something is moving.
Kohring and colleagues analysed nationwide outpatient claims data for women and girls aged 10 to 52 with statutory health insurance, with a first diagnosis of N80 and at least two years of prior observation.
The incidence of diagnosed endometriosis rose from 2.8 per 1000 persons at risk in 2014 to 4.1 per 1000 in 2022, a relative increase of 44 percent. The median age at first diagnosis fell from 37 to 34 years. The authors attribute this above all to increased awareness and better detection.
For you that means: according to this analysis endometriosis is probably not becoming more common. It is being found more often, and the median age at first diagnosis was three years lower in 2022 than in 2014. So attention does change something measurable.
Kohring C, Akmatov MK, Holstiege J, Brandes I, Mechsner S. Deutsches Ärzteblatt International 2024;121(19):619-626. DOI: 10.3238/arztebl.m2024.0160 · PMID: 39189056 [Real-World, claims data]The most common story about the diagnostic delay goes: nobody listened to me. That happens, and it is hurtful. But it is not the complete description.
The more precise description goes: an explanation was found every single time. Irritable bowel. Stress. A sensitive stomach. A demanding phase of life. Each of these explanations was plausible in itself, and that is exactly why the search stopped every time.
A diagnosis does not come about because someone has more compassion. It comes about because someone asks the right question and then uses the right tool. Both can be learned, and both can be prepared for. That is what the rest of this text is about.
And now you know why the number is so large: not because nobody looked for ten years, but because for ten years something else was found.
Why severe period pain passes as normal for so long
Picture a school class. Midweek, third period. Of the girls in the room a large share have period pain this week, a few are taking something for it, one is at home in bed. If you are the one in that class whose pain is different, you will not stand out. You will think you simply drew the short straw.
That is not a guess. That is what the numbers show.
Armour and colleagues pooled 38 studies with 21 573 young women under 25 years, with a search up to June 2018.
The prevalence of dysmenorrhoea was 71.1 percent, independent of the economic status of the country. 20.1 percent reported absences from school or university because of period pain, and 40.9 percent an impairment of performance or concentration in class.
For you that means: seven in ten young women have period pain. This number describes period pain and not endometriosis, which is an important difference. But it explains why a particular kind of pain disappears inside a very common experience.
Armour M, Parry K, Manohar N et al. Journal of Women's Health 2019;28(8):1161-1171. DOI: 10.1089/jwh.2018.7615 · PMID: 31170024 [Meta-analysis]Period pain is a topic of its own, and not every severe cycle pain goes back to endometriosis. What else can be behind it is covered in PMS and cycle symptoms.
Ballard and colleagues conducted semi-structured interviews in southeast England with 32 women from a chronic pelvic pain clinic, 28 of whom were later diagnosed with endometriosis.
The paper describes the delay on two levels that work together: the women themselves classified their symptoms as normal, and in general practice the same thing happened. Two further mechanisms came on top: hormonal treatments dampened the symptoms, and there was reliance on investigations that cannot distinguish between the possible causes.
For you that means: the sentence the pill did improve it looks like a settled question in a medical record. But it often only describes a dampening. The question of what lies underneath stays unanswered.
Ballard K, Lowton K, Wright J. Fertility and Sterility 2006;86(5):1296-1301. DOI: 10.1016/j.fertnstert.2006.04.054 · PMID: 17070183 [Real-World, qualitative interview study]Hormonal treatment is not a mistake
Empirical hormonal treatment is guideline-compliant and a recognised part of the diagnostic path. The ESHRE guideline explicitly names the option of combining imaging with empirical treatment and recommends discussing the pros and cons with the patient [Guideline]. The German S2k guideline lists primary hormonal treatment as first-line therapy [Guideline].
The side effect is real nonetheless: when symptoms quieten down, the search continues less often. Both sides of this argument belong together.
What explicitly does not follow from this: an ongoing hormonal treatment, whether the pill, a progestogen or another preparation, is not stopped, paused or reduced on your own to make a diagnosis possible. Whether and how something like that makes sense belongs in a conversation with your gynaecologist and is medically supervised.
Now to the question that is often phrased online as an accusation: why do colleagues not notice this.
I think the most honest answer is a structural one. In a gynaecology appointment in standard care, only a few minutes are often scheduled. A structured endometriosis history across several pain sites and several body systems takes considerably longer. An endometriosis ultrasound to international standard also takes longer than an orienting look at uterus and ovaries, and it is a skill in its own right that has to be acquired first. Numbers on that further down.
This is not an accusation aimed at a profession. It is a description of time budgets and training priorities. Anyone who understands that walks into the next appointment differently: not suspicious, but prepared. And preparation really is the lever you hold in your hand.
Normal and common are not the same thing. Common means: many people have it. Normal means: it belongs there and needs no explanation.
Period pain is common. Pain that regularly takes you out of school, university or work is not normal, no matter how many women know it. The yardstick is not whether others have pain too. The yardstick is what the pain does to your life.
And now you know why the sentence that is normal held up for so long: because it is statistically true and can still be wrong for you.
The symptoms nobody connects with the uterus
I often ask about bowel movements in my consultations, and regularly an irritated look comes back. What does the gut have to do with the menstrual cycle. A great deal, sometimes. And it is exactly here that the diagnostic path often branches off in the wrong direction.
Endometriosis is so hard to pin down because it does not stick to the organ it is named after. It can show up on the peritoneum, on the ovaries, on the ligaments of the uterus, on the front wall of the rectum, on the bladder, on the diaphragm. And the symptoms follow the location, not the name.
The language in which endometriosis announces itself
- Dysmenorrhoea
- Period pain that is stronger than in others, that starts earlier, that does not settle sufficiently with painkillers, that tends to increase rather than decrease over the years.
- Dyschezia
- Pain when passing stool, typically with a cyclical pattern, often around the bleeding, sometimes with alternating constipation and diarrhoea.
- Dysuria
- Pain when urinating or frequent urge without evidence of an infection, likewise often cyclical.
- Dyspareunia
- Deep pain during sex, not at the entrance but deep inside, often varying in intensity with position and with the day of the menstrual cycle.
- Cyclical back and leg pain
- Pain that pulls into the lower back, the buttock or one leg and follows the menstrual cycle rather than physical strain.
- Exhaustion
- A tiredness that sleep does not refill and that stays outside the bleeding too.
None of these signs proves endometriosis on its own. And none of these symptoms goes away because it appears on this list. They are pieces of a puzzle for a conversation, not for self-diagnosis.
Ramin-Wright and colleagues compared 560 women with surgically and histologically confirmed endometriosis with 560 controls at clinics and practices in Switzerland, Germany and Austria, matched for age and ethnic background.
Frequent exhaustion was reported by 50.7 percent of the women with endometriosis against 22.4 percent of the controls. The exhaustion was associated with insomnia, with depression, with pain and with occupational stress. Important for the interpretation: it was independent of age, of time since first diagnosis and of the stage of the disease.
For you that means: the exhaustion is not a sign that you are not pulling yourself together enough. It belongs to the picture, and the fact that it did not depend on the stage weakens the objection that it is only a consequence of particularly severe disease.
Ramin-Wright A, Kohl Schwartz AS, Geraedts K et al. Human Reproduction 2018;33(8):1459-1465. DOI: 10.1093/humrep/dey115 · PMID: 29947766 [Case-Control, human]And then there is the diagnosis that appears in this story almost every time: irritable bowel syndrome.
A group at Aarhus University Hospital surveyed 356 women online, 254 of them with a self-reported endometriosis diagnosis, and recorded irritable bowel syndrome both through a pre-existing diagnosis and through the Rome III criteria.
The odds ratio for irritable bowel syndrome in endometriosis was 5.32. In the analysis restricted to women without bowel involvement of the endometriosis it was 6.54. Adjustment was made for age, comorbidities of the digestive tract and years of education.
For you that means: the overlap does not depend on whether lesions sit in the bowel. That is why the irritable bowel diagnosis is so often the first one made, and why it does not replace the gynaecological assessment.
Schomacker ML, Hansen KE, Ramlau-Hansen CH, Forman A. European Journal of Obstetrics, Gynecology and Reproductive Biology 2018;231:65-69. DOI: 10.1016/j.ejogrb.2018.10.023 · PMID: 30326376 [Real-World, cross-sectional, human]Junkka and Ohlsson analysed 2200 women with data from medical records in the Malmö Offspring Study, 1915 of them with a completed questionnaire, with endometriosis taken from the national register.
Of 72 participants with endometriosis, 21, that is 29.2 percent, reported irritable bowel syndrome, against 22.8 percent in the whole questionnaire group, with an odds ratio of 1.86. A second result is decisive: between endometriosis and irritable bowel syndrome there were no differences in the gastrointestinal symptoms themselves.
For you that means: from the description of your abdominal symptoms alone it cannot be read off which of the two diagnoses applies. That is exactly why one so easily hides the other.
Junkka SS, Ohlsson B. BMC Gastroenterology 2023;23(1):228. DOI: 10.1186/s12876-023-02861-w · PMID: 37400789 [Cohort, human]So irritable bowel syndrome is not a misdiagnosis in the sense of carelessness. It is a diagnosis that fits the symptoms and that still does not have to be the only explanation. Both can exist side by side. If your abdomen plays the leading role, you will find the context in Irritable bowel syndrome and its causes, and the link between the menstrual cycle and digestion in The menstrual cycle and digestion.
There is one question that sums up this whole section, and it is short: does your symptom follow the calendar.
It is not how strong the pain is that decides the trail, but whether it has a pattern. Pain when passing stool that appears every month around the same cycle days tells a different story from pain when passing stool that is randomly distributed. That is why the cycle day is the most important column in any pain diary.
And now you know why so many paths lead to gastroenterology first: because the abdomen is louder than the pelvis, and because both diagnoses speak the same language.
Why a normal ultrasound rules nothing out
There is one sentence that takes many women out of the diagnostic process for years, and it is well meant: the ultrasound is all fine. You go home relieved. And you go home with a piece of information that says less than it sounds like.
The reason is statistical, not personal. A test can be very good at finding something and at the same time poor at ruling it out. That is exactly the situation here.
Imaging belongs in the diagnostic work-up. A negative finding does not rule out endometriosis, especially not the superficial peritoneal form.
Paraphrased translation of the ESHRE recommendation of 2022 [Guideline]This is not a marginal note in an appendix. It is a strong recommendation in the diagnostics chapter of the European guideline, formulated by the European Society of Human Reproduction and Embryology, with literature up to December 2020 and 109 recommendations in total [Guideline].
Nisenblat and colleagues examined in a Cochrane review whether an imaging procedure could replace diagnostic surgery, with predefined thresholds of at least 94 percent sensitivity and at least 79 percent specificity.
Not a single procedure met these criteria for pelvic endometriosis overall. For endometriomas, transvaginal ultrasound reached a sensitivity of 0.93 and a specificity of 0.96. For deep infiltrating endometriosis the values were 0.79 and 0.94. The authors themselves rate most of the included studies as methodologically poor, and that belongs alongside each of these numbers.
For you that means: when the ultrasound sees something, that is very informative. When it sees nothing, that is considerably less informative. That is the whole difference between a rule-in and a rule-out test.
Nisenblat V, Bossuyt PMM, Farquhar C, Johnson N, Hull ML. Cochrane Database of Systematic Reviews 2016;2(2):CD009591. DOI: 10.1002/14651858.CD009591.pub2 · PMID: 26919512 [Meta-analysis, Cochrane]Four forms, one name
- Superficial peritoneal endometriosis. Flat lesions on the peritoneum, often only a few millimetres thick. They do not change the shape of the organs and cast no shadow. As a rule the ultrasound does not see them.
- Endometrioma. A cyst on the ovary with a typical internal pattern. This is the form the ultrasound picks up well, with a sensitivity of 0.93 in the Cochrane review.
- Deep infiltrating endometriosis. Nodules that grow deeper than five millimetres under the peritoneum, on the ligaments, the rectum, the bladder or the vaginal wall. They are visible when they are specifically looked for, and invisible when they are not.
- Adenomyosis. Lesions in the muscle layer of the uterus itself. It has its own ultrasound signs and often occurs together with the other forms.
A normal ultrasound above all does not rule out the first form, and it is precisely this form that can cause considerable pain. That is the reason the guideline puts the sentence so clearly.
How large this gap is can be quantified. In the international pilot study on structured ultrasound the negative predictive value for the deep infiltrating form was 68.4 percent against surgical visual diagnosis and 74.6 percent against tissue examination. Translated: even with very experienced examiners, a normal finding was falsely reassuring in about a quarter to a third of those women. The numbers of that study appear in full in the next section.
And why the colonoscopy rules nothing out either
Many women with pain when passing stool have a colonoscopy behind them, with a normal result, and draw the wrong conclusion from it.
The explanation is simple and anatomical. A colonoscopy looks at the mucosa from the inside. Endometriosis lesions typically sit on the outside of the bowel wall and grow into the wall from there. Very often they never reach the mucosa. What would be visible from the inside then simply does not exist.
That is why a normal colonoscopy is not an exclusion. It still remains a sensible investigation, because it clarifies other causes, and with blood in the stool it belongs there anyway. What happens during it and how to prepare is covered in Colonoscopy, what to expect.
A finding without abnormalities is not a statement about you. It is a statement about the reach of the procedure.
The sentence you can keep is this: imaging is good at finding and weak at ruling out. Anyone who knows that reads a normal report differently. Not as an acquittal, but as one piece of information among several.
And now you know why a normal ultrasound does not explain your symptoms: because it can only see part of endometriosis at all.
What a practised examiner sees, and what that does to your appointment
Two women with the same symptoms go for an ultrasound. For one, the report afterwards says normal. For the other, there is a paragraph about the pouch of Douglas, about the mobility of the rectum and about a nodule on the ligaments. Both had the same disease.
This is the practically most important piece of information in this article, because it decides your next step. An endometriosis ultrasound is not the same thing as a gynaecological ultrasound. It is a separate, structured examination with a defined protocol.
The International Deep Endometriosis Analysis Group, IDEA for short, set out in a 2016 consensus statement which terms, definitions and measurements belong to the ultrasound features of the different forms of endometriosis.
The document contains no accuracy values, it is a nomenclature and protocol document. It describes what is systematically assessed: the anterior compartment with bladder and ureters, the uterus including signs of adenomyosis, the ovaries, the mobility of the organs relative to one another, and the posterior compartment with the pouch of Douglas, the ligaments, the vaginal wall and the rectum [Guideline].
For you that means: there is an internationally agreed protocol for this examination. Anyone who applies it searches differently from someone who only looks at uterus and ovaries.
Guerriero S, Condous G, van den Bosch T et al. Ultrasound in Obstetrics & Gynecology 2016;48(3):318-332. DOI: 10.1002/uog.15955 · PMID: 27349699 [Guideline]Djokovic and colleagues developed recommendations for the International Society for Gynecologic Endoscopy on structured reporting of dynamic ultrasound where endometriosis is suspected.
With grade of recommendation 1C, adoption of the IDEA terms and methodology is recommended, because they are the most comprehensive concept available. With grade 1B it is recommended to summarise the findings in the #Enzian classification. The conclusion: ultrasound mapping of pelvic endometriosis is accurate when trained examiners carry it out [Guideline].
For you that means: a good ultrasound report is structured and traceable. The word normal on its own is not a report, it is a summary.
Djokovic D, Pinto P, van Herendael BJ et al. European Journal of Obstetrics, Gynecology and Reproductive Biology 2021;263:252-260. DOI: 10.1016/j.ejogrb.2021.06.035 · PMID: 34242934 [Guideline]The sliding sign, explained in one paragraph
The pouch of Douglas is the pocket between the uterus and the rectum. In a healthy state the organs lie loosely against each other there and can be shifted against one another, like two pages of a book sliding past each other.
With the sliding sign the examiner looks at exactly that. She applies gentle pressure with the probe and watches whether the rectum glides smoothly over the back of the cervix and uterus. If it glides, that speaks for a free pouch of Douglas. If it does not glide, that speaks for adhesions. It takes seconds, as a rule it does not hurt, and it shows something that stays invisible on a still image.
Reid and colleagues had recorded videos from 30 women with chronic pelvic pain assessed independently by six people, four with a focus on gynaecological ultrasound and two from prenatal diagnostics.
Across all six, agreement was at Cohen's kappa 0.354 to 0.927, while among the four gynaecological sonographers it was 0.630 to 0.927. The area behind the cervix was easier to assess than the area at the posterior fundus. The high accuracy values of the four gynaecological raters, however, apply only after excluding the cases rated as uncertain, and surgical data were available for only 24 of the 30 videos.
For you that means: the sliding sign can be reliable when someone applies it routinely. Between routine and no routine there is a visible difference.
Reid S, Lu C, Casikar I et al. Human Reproduction 2013;28(5):1237-1246. DOI: 10.1093/humrep/det044 · PMID: 23482338 [Real-World, reproducibility study]Leonardi and colleagues tested transvaginal ultrasound according to the IDEA consensus against visual diagnosis at laparoscopy and against tissue examination at eight centres in six countries between August 2018 and November 2019.
All of the following accuracy figures refer to deep infiltrating endometriosis. Against surgical visual diagnosis, accuracy was 86.1 percent, sensitivity 88.4 percent, specificity 78.8 percent, positive predictive value 92.9 percent and negative predictive value 68.4 percent. Against tissue examination the values were 85.9, 89.8, 75.9, 90.4 and 74.6 percent. Of the 273 participants, 256 had histologically confirmed endometriosis, 190 of them a deep infiltrating form.
For you that means: a structured ultrasound with someone experienced brings a great deal, above all when it finds something. And even then a normal finding is not an exclusion.
Leonardi M, Uzuner C, Mestdagh W et al. Ultrasound in Obstetrics & Gynecology 2022;60(3):404-413. DOI: 10.1002/uog.24936 · PMID: 35561121 [Cohort, diagnostic accuracy, n=273]Now comes the honest part, and it matters, because it frees the question of experience from any accusation.
Between December 2017 and December 2018, three gynaecology trainees each carried out 50 examinations, blinded to history and reference finding, with feedback from an experienced examiner immediately afterwards, analysed with the CUSUM method.
Overall accuracy was 90 percent for bowel involvement and 93 percent for the assessment of the pouch of Douglas. For bowel involvement, one of the three did not reach the competence threshold after 50 examinations, the other two needed 21 and 25. For obliteration of the pouch of Douglas, a different one did not reach the threshold, the other two needed 40 and 22.
For you that means: this skill does not appear on the side. It needs repetition, feedback and time. That is why asking about experience is a factual question and not an expression of mistrust.
Leonardi M, Ong J, Espada M et al. Journal of Ultrasound in Medicine 2020;39(12):2295-2303. DOI: 10.1002/jum.15337 · PMID: 32412170 [Real-World, learning curve study]How to ask about experience without being rude
- Ask about the procedure, not about the skill. For example: will the posterior compartment be assessed in my case as well.
- Ask about the sliding sign by name. Anyone who does it regularly understands the question immediately. Anyone who does not know it then also knows why you are asking.
- Ask about the report format. Will I get a structured written report, ideally with the #Enzian system.
- Say what has already been ruled out. Two sentences about previous findings save ten minutes of questions.
- Ask about the next step if the finding is normal. This question is the most important one, because it prevents the work-up from ending with a normal.
It feels presumptuous to ask in a practice about how an examination is done. It is not.
You are not asking whether someone is good. You are asking whether a particular procedure is used, the same way you ask about the equipment on a car and not about the competence of the garage. Most colleagues are happy to answer this question, because it clarifies what the appointment is meant to achieve. And if the answer is that this examination is not offered there, that is useful information and not an insult.
And now you know why two ultrasound reports for the same disease can turn out so differently: because the examination is a search strategy and not just an image.
MRI, and when it is really needed
When the ultrasound finds nothing, many women wish for an MRI. That is understandable, because a more elaborate investigation sounds like more certainty. Only an MRI is not a better ultrasound. It is a tool for particular questions.
An expert group of the European Society of Urogenital Radiology developed indications, technical requirements, patient preparation, examination protocols and reporting criteria for MRI of pelvic endometriosis, with evidence grading according to OCEBM 2011.
It is recorded there that the accepted first imaging step is pelvic ultrasound and that MRI is increasingly used as an additional investigation in complex cases and for surgical planning [Guideline].
For you that means: the preparation helps decide how informative the result is. If you are told to come fasting or on a particular day of your menstrual cycle, there is a reason for it.
Bazot M, Bharwani N, Huchon C et al. European Radiology 2017;27(7):2765-2775. DOI: 10.1007/s00330-016-4673-z · PMID: 27921160 [Guideline]| Question | Transvaginal ultrasound | MRI |
|---|---|---|
| Endometrioma, sensitivity | 0.93 | 0.95 |
| Endometrioma, specificity | 0.96 | 0.91 |
| Deep infiltrating form, sensitivity | 0.79 | 0.94 |
| Deep infiltrating form, specificity | 0.94 | 0.77 |
| Data base | up to 934 participants | up to 266 participants |
A narrative review rates both procedures as comparable in accuracy and names the most important limit of the transvaginal approach: whatever lies above the rectosigmoid junction simply no longer comes into the field of view [Review]. That is exactly where one of the sensible indications for an MRI lies.
When an MRI is a good idea
- Where deep infiltrating forms are suspected
- Above all when symptoms point to bowel, bladder or ureter and the ultrasound cannot reliably map the extent.
- For surgical planning
- When surgery is on the table, the team needs a map. The MRI provides one across a larger area than transvaginal ultrasound.
- When the transvaginal approach is not possible
- For example with severe pain during the examination, or when a vaginal examination is not an option for other reasons.
- When lesions above the rectosigmoid junction are suspected
- That is where the reach of transvaginal ultrasound ends.
And when rather not: as a first step instead of a structured ultrasound, or in the hope that a normal MRI rules out endometriosis. It can do that just as little as the ultrasound.
More technology does not automatically mean more answer. With endometriosis ultrasound the search strategy decides the result, with MRI the protocol and the question do.
An MRI without a clear question often delivers only one more sentence containing no evidence of. An MRI with a clear question can make surgery unnecessary or prepare it. It is worth clarifying beforehand which question is to be answered.
And now you know why the MRI is not the next logical step after every normal ultrasound: because it answers a different question.
The change many people do not know about: diagnosis without laparoscopy
There is a sentence I hear regularly in my consultations, and it is now outdated: you only know for certain after a laparoscopy. Many women have been carrying this sentence around for years. Some have postponed the work-up because of it, because surgery is a big hurdle when you do not know whether it is worth it.
That hurdle has become smaller since 2022.
The European Society of Human Reproduction and Embryology published a structurally developed guideline on endometriosis in 2022, with literature up to 1 December 2020 and chapters on diagnostics, pain, fertility, recurrence, adolescence and postmenopause.
In the abstract the guideline explicitly questions laparoscopy and tissue examination as gold standard tests. Laparoscopy is recommended as good clinical practice for the case where imaging stays negative or where empirical treatment has not carried or is not an option. And at the same time the guideline records that a negative tissue examination does not fully rule out the disease either [Guideline].
For you that means: you do not have to undergo surgery to get a diagnosis if the symptom picture and the imaging fit together. And conversely it still holds: a normal finding is not an acquittal.
Becker CM, Bokor A, Heikinheimo O et al. Human Reproduction Open 2022;2022(2):hoac009. DOI: 10.1093/hropen/hoac009 · PMID: 35350465 [Guideline]The S2k guideline on the diagnosis and treatment of endometriosis, AWMF register 015/045, was developed in a structured consensus process with 37 professional societies, organisations and patient support groups, with a systematic literature search for the years 2019 to 2023. The April 2025 version was published as an editorially revised long version on 21 October 2025 and applies until March 2030.
It contains 25 statements and 73 recommendations. As the central innovation, the abstract names transvaginal ultrasound as the key diagnostic procedure for detecting endometriosis. Therapeutically, primary hormonal treatment is recommended as first choice, with surgical and multimodal approaches added individually and symptom-oriented [Guideline].
For you that means: the German and the European guideline point in the same direction. Ultrasound is at the centre, not surgery.
Burghaus S, Schäfer SD, Bär KJ et al. Geburtshilfe und Frauenheilkunde 2026;86(2):133-188. DOI: 10.1055/a-2760-4867 · PMID: 41684533 [Guideline]That this step was perceived within the field as a break with previous practice is documented. A commentary in a specialist journal describes how the 2022 guideline points in different directions from its predecessors in diagnosis and treatment while becoming more precise and more applicable [Review]. So this is not a fringe opinion.
It does not follow that surgery is superfluous
Laparoscopy remains an important procedure. It is still the way forward when imaging stays negative and the symptoms persist, when an empirical treatment has not carried or is not an option, and it is often the most sensible option when treatment is planned anyway, because the diagnostic and therapeutic step then fall together in one procedure.
Where surgery is indicated, it stays indicated. That decision is made by your treating gynaecologist together with you, based on findings, symptoms and life situation. A blog article cannot replace that weighing up, and it is not meant to postpone it either.
What has changed is something else: you no longer have to undergo surgery just to get a name for your symptoms.
How the work-up is structured today
Structured history and pain diary
The symptoms documented across at least two to three menstrual cycles, with the cycle day. Plus the clinical examination, which according to ESHRE should explicitly be considered, even though its accuracy on its own is low [Guideline].
pattern instead of snapshotTransvaginal ultrasound following the IDEA system
Both compartments, mobility of the organs, sliding sign, assessment of the pouch of Douglas, structured report.
rule-in strong, rule-out weakMRI for particular questions
Where deep infiltrating forms are suspected, with lesions beyond the reach of ultrasound and for surgical planning.
map for the procedureMaking the diagnosis when clinical picture and imaging fit together
Explicitly possible since ESHRE 2022, without surgery. Treatment can build on that.
without laparoscopyLaparoscopy when imaging stays negative
Or when an empirical treatment has not carried or is not an option, or when surgical treatment is planned at the same time.
diagnosis and therapy in oneThis path is a description of the guideline logic, not a plan for an individual case. In which order and at what pace things proceed for you is decided by your treating doctor together with you.
Many women believe that laparoscopy is what it takes to be taken seriously. A finding on paper, visible, with images, irrefutable.
That wish is understandable when you have had to fight for credibility for years. But the guideline now says something different: your description of your symptoms is a diagnostic instrument. It is not the prelude to the real investigation. It is part of it.
And now you know why it is worth raising this point in your appointment: because it can shorten the path to a diagnosis by one procedure.
Why there is no reliable blood test
The question comes up in almost every consultation: can this not simply be measured in the blood. It would be lovely. It would save years. And the state of things is uncomfortably clear at this point.
The ESHRE guideline puts it as a strong recommendation: biomarkers in endometrium, blood, menstrual or uterine fluid should not be used for the diagnosis of endometriosis [Guideline]. That is unusually clear for a guideline document.
A second Cochrane review examined 15 different combinations of blood, urine or tissue biomarkers, transvaginal ultrasound and history or clinical examination, against surgical diagnosis as the reference. In its introduction the review notes that about 10 percent of women of reproductive age are affected.
Some combinations worked as a rule-in test, for instance transvaginal ultrasound plus CA-125 from 25 U/ml or CA 19-9 from 12 U/ml for endometrioma with a sensitivity of 0.79 and a specificity of 0.97, or vaginal examination plus ultrasound for an obliterated pouch of Douglas with 0.87 and 0.98. All confidence intervals were wide, all studies of poor methodological quality. The conclusion: none of the biomarkers examined could be meaningfully assessed, and non-invasive tests should not be used outside of research settings.
For you that means: there is currently no test that can be taken from you and then say whether you have endometriosis or not.
Nisenblat V, Prentice L, Bossuyt PMM, Farquhar C, Hull ML, Johnson N. Cochrane Database of Systematic Reviews 2016;7(7):CD012281. DOI: 10.1002/14651858.CD012281 · PMID: 27405583 [Systematic Review, Cochrane]CA-125, placed in context in one minute
CA-125 is a protein that passes into the blood in increased amounts when the peritoneum is irritated. It is not an endometriosis marker. It also rises with ovarian cysts, with inflammation in the pelvis, with liver disease, in pregnancy, and it fluctuates across the menstrual cycle as well.
A team around Hirsch pooled 22 studies with 3626 participants and pooled 14 of them with 2920 participants at a threshold of 30 U/ml, with histologically confirmed endometriosis as the reference.
The pooled specificity was 93 percent, the pooled sensitivity 52 percent. In moderate or severe endometriosis CA-125 was considerably more sensitive than in minimal disease, namely 63 percent against 24 percent. The authors' conclusion: CA-125 is suitable as a rule-in test, but a value below 30 U/ml cannot rule out endometriosis.
For you that means: a high value can support the suspicion and shorten the path. A normal value says almost nothing, especially in mild disease. Exactly one in four women with minimal endometriosis would have had an abnormal value in these studies.
Hirsch M, Duffy JMN, Davis CJ, Nieves Plana M, Khan KS. BJOG 2016;123(11):1761-1768. DOI: 10.1111/1471-0528.14055 · PMID: 27173590 [Meta-analysis]The guideline says no, the meta-analysis says yes. So which is it
The contradiction is not one, as soon as you separate the question. The meta-analysis rates CA-125 as a suspicion booster in a group where the suspicion already exists. The guideline rejects it as a diagnostic criterion, because a normal value would then be read as an all-clear.
And that is exactly what the guideline protects against: false reassurance. Anyone using a test in endometriosis diagnostics whose sensitivity in minimal disease is 24 percent risks sending three out of four women home.
The new saliva tests, placed in context honestly
For some years now, work has been going on with saliva signatures from microRNA, that is short snippets of genetic material that say something about gene activity in the body. In 2025 a large external validation appeared, and the numbers are remarkable.
Bendifallah and colleagues prospectively and multicentrically validated a saliva miRNA signature in 971 patients aged 18 to 43 with symptoms suspicious for endometriosis, from different levels of care, with blinded analysis of the saliva signature.
Accuracy was 96.6 percent, sensitivity 97.3 percent, specificity 94.1 percent, positive predictive value 98.2 percent and negative predictive value 91.3 percent. Among the surgically confirmed cases, misclassification, underestimation and overestimation were 4.6, 2.4 and 2.2 percent for the saliva signature against 27.2, 15.1 and 12.2 percent for imaging.
For you that means: this is the most interesting development of recent years in this field. And it comes with caveats that belong in the same paragraph.
Bendifallah S, Roman H, Suisse S et al. NEJM Evidence 2025;4(11):EVIDoa2400195. DOI: 10.1056/EVIDoa2400195 · PMID: 41147827 [Cohort, external validation, n=971]Why I am still waiting here
- Funding by the manufacturer
- The study was funded by the company that offers the test. That does not make the numbers wrong, but it calls for independent confirmation.
- A prevalence of 77 percent in the group studied
- Three in four participants actually had endometriosis. Predictive values depend strongly on how common a condition is in the group studied. In a less preselected group they would turn out differently.
- Methodological groundwork from the same team
- The underlying signature comes from a sequencing study by the same working group. There the individual markers on their own ranged from sensitivities of 5.8 to 97.4 percent, so the performance only emerges from the algorithm. That is exactly why independent validation counts for so much here.
- Not in the guidelines, not a standard covered service
- Neither ESHRE 2022 nor the German S2k version of 2025 anchors the test. In Germany it is currently not a service covered by statutory health insurance. The available cost-effectiveness calculation also comes from the same environment as the validation.
My assessment: promising, independent confirmation still pending. I deliberately name no provider, no product name and no source of supply, because this is not purchasing advice.
A test is not a diagnosis. A test shifts a probability.
Once you have taken that in, you read every lab sheet differently. The question is never is the value normal. The question is: how likely was it before, how likely is it now, and does this result change the next step. If a test does not change the next step, you do not need it.
And now you know why nobody has offered you a blood test so far: because there is none that answers the question you have.
Endometriosis centres, the pain diary and what you bring along
If you have read this far, you know that the path to a diagnosis depends less on your luck than on two things: on the quality of the history taking and on the quality of the examination. You can influence both, though not completely.
Let us start with the centres, because that is where both come together.
In the German-speaking countries, endometriosis centres are certified by EuroEndoCert, on behalf of the Stiftung Endometrioseforschung and the European Endometriosis League. The basis is the S2k guideline in its current version. There are several levels, ranging from a practice with an endometriosis clinic to a centre working surgically and across disciplines. What a higher level mainly means is one thing: regularity. Whoever sees many women with this disease searches differently and finds differently.
That does not mean you need a centre for the first step. It means a centre is the right address when the question of a structured ultrasound, of surgical planning or of a complex finding is on the table.
One point that must not be missing here, even though this article is about diagnostics: if you are trying to conceive, it belongs in the conversation from the very first appointment. The work-up of your symptoms and the fertility work-up then run alongside each other and not one after the other. Time is a real factor in this field. That is why a recommended investigation or consultation is not postponed just because a finding is still open or because you want to try something else first. What makes sense in your case and in which order is something you discuss with your gynaecologist and, when it comes up, with a fertility clinic.
The pain diary, and why two to three cycles are the minimum
A single bad month says little. A pattern across three menstrual cycles says a great deal. The difference lies not in the amount of information but in its structure.
If you tell a doctor that you have severe pain, that is a description. If you say that pain when passing stool regularly occurs on cycle days 26 to 3, that the painkillers are not enough on two days per cycle and that you missed six days in the last quarter, that is a finding. The same suffering turns into information someone can work with.
What belongs in a pain diary
- Date and cycle day. The most important column. Without it, every list of complaints stays a collection without a pattern.
- Pain intensity from 0 to 10. Once a day, always at the same time of day, so the values stay comparable.
- Location and radiation. Lower abdomen left or right, lower back, buttock, leg, deep in the vagina.
- Triggers and relief. What makes it worse, what makes it more bearable.
- Painkillers. Which one, how often, and whether it carried.
- Bowel movements and urination. Pain, frequency, consistency, blood.
- Sexuality. Pain during sex, whether superficial or deep, on which cycle days.
- Exhaustion and sleep. Also from 0 to 10, because exhaustion belongs to the picture.
- Days lost. School, university, work, cancelled plans. This number often carries furthest in conversations.
What else you bring along
Previous findings, and as complete as possible: ultrasound images and reports, operation notes if there are any, findings from gastroenterology or urology if a search has already happened there.
A complete medication list, explicitly including hormonal contraception, because hormonal treatment changes the symptom picture and the examination has to be read differently. And because from that follows what I already wrote above: these medicines are not changed on your own, they are brought into the conversation.
And three written-down questions. Not ten. Three. They make sure that after the appointment you are not sitting in the car realising that exactly the most important thing did not come up.
The clinical examination including vaginal palpation belongs there according to ESHRE, in order to detect deep nodules or endometriomas, even though its accuracy on its own is low [Guideline]. If this examination is very painful for you, say so beforehand. That is itself a piece of diagnostic information.
Why pain can persist even though the findings look good
This is the question I am asked most often, and it deserves an honest answer. Some women still have pain after successful surgery. Some have severe pain with small findings. And neither is a contradiction, once you understand that pain has a system of its own.
Orr and colleagues followed 239 patients aged 18 to 50 with confirmed or suspected endometriosis and surgery after the baseline appointment at a tertiary centre for endometriosis and pelvic pain in British Columbia, with a mean follow-up of 16.1 months.
The mean baseline score on the Central Sensitization Inventory was 43.8 out of a maximum of 100. Higher baseline scores went along with stronger symptoms at follow-up, and that held even after controlling for baseline pain scores: chronic pelvic pain with an odds ratio of 1.02, deep dyspareunia 1.03, dyschezia 1.03 and back pain 1.02.
For you that means: when pain persists even though the findings look good, that is no proof that there was nothing there. A second mechanism may have joined in, one that needs its own treatment.
Orr NL, Huang AJ, Liu YD et al. JAMA Network Open 2023;6(2):e230780. DOI: 10.1001/jamanetworkopen.2023.0780 · PMID: 36848090 [Cohort, prospective, n=239]The German S2k guideline treats nociplastic pain mechanisms and central sensitization as a topic in their own right, with a dedicated table of clinical clues and another on risk factors for pain chronification [Guideline]. That is remarkable, because it shows that the guideline and an integrative view say the same thing at this point: the pain needs its own address, not only the finding.
Central sensitization does not mean the pain is imagined. It describes a nervous system that has learned to turn signals up louder. That is a description of biology, not a judgement about your psyche. And it can be treated, in a different register from surgery.
And why in this practice I additionally ask about your surroundings
If you come to me, you will get questions you rarely hear in a gynaecology appointment. About mould in your home. About exposures at work. About chronic stress, about the gut, about the inflammatory load across the years.
The evidence-based core behind this is modest and honestly named: in a preregistered meta-analysis of purely human epidemiological studies, the pooled odds ratios were 1.65 for dioxins, 1.70 for polychlorinated biphenyls and 1.23 for organochlorine pesticides, with explicit reference to considerable heterogeneity and small effect sizes. The level of evidence was rated as moderate with serious risk of bias [Meta-analysis, observational studies, human]. These are observational data in humans, not intervention studies.
It explicitly does not follow from this that there is an environmental cause behind every endometriosis. It only follows that the question is not absurd and that it is rarely asked in standard care for understandable reasons: because an observational association with a serious risk of bias does not lead to any diagnostic or therapeutic consequence with proven benefit. I do not go deeper into the question of causes here but in Endometriosis, causes seen integratively. If you want to know what xenoestrogens even are, that is covered in Xenoestrogens in everyday life.
Environmental factors are a topic, not an enemy
I notice something that worries me. Some women read a text like this one and afterwards start to mistrust their own home. Everything becomes a possible source. Foods get cut, cosmetics thrown out, invitations declined because you do not know what was used in someone else's kitchen.
That is the point at which a sensible question tips into something that costs more than it brings in. A narrowing daily life, constant vigilance and a guilty conscience after every meal are themselves a burden. Where food is affected, the boundary to disordered eating can become blurred, and that is covered in Eating disorders between body and mind.
My yardstick is simple: a measure has to make your life lighter, not narrower. If you notice with a change that it creates anxiety instead of calm, then it is the wrong measure at this point, even if it would make sense in theory.
And now you know why the question about your surroundings is part of my consultation and why it never takes the place of the gynaecological work-up: it comes on top, not before.
Frequently asked questions
How long does it usually take before endometriosis is recognised?
In a questionnaire study at centres in Austria and Germany, a median of 10.4 years lay between the first symptoms and the diagnosis, and 74 percent of the 171 women surveyed had received at least one wrong diagnosis before that. An international survey with 2017 participants from 63 countries arrived at an average of 9.6 years, split into 3.7 years until the first medical appointment and 5.8 years from that first appointment to the diagnosis. A systematic review of 17 observational studies found values between 0.3 and 12 years depending on definition and country. These three numbers do not measure the same thing and therefore cannot be added up against each other.
Can I get an endometriosis diagnosis without a laparoscopy?
Yes, that has been explicitly provided for since the ESHRE guideline of 2022. The guideline questions laparoscopy and tissue examination as the gold standard and recommends laparoscopy for the case where imaging stays negative or where empirical treatment has not carried or is not an option. The German S2k guideline in its 2025 version places transvaginal ultrasound at the centre as the key diagnostic procedure. It does not follow from this that surgery would be superfluous. Where it is indicated, it stays indicated, and that decision is made by your treating gynaecologist together with you.
My ultrasound was normal. Does that mean I do not have endometriosis?
No. The ESHRE guideline says this unusually clearly: a negative finding does not rule out endometriosis, especially not the superficial peritoneal form. In the international IDEA pilot study with 273 patients, the negative predictive value of structured ultrasound for the deep infiltrating form was 68.4 percent against surgical visual diagnosis and 74.6 percent against tissue examination. So a normal finding was falsely reassuring in roughly a quarter to a third of those cases, and that was in a particularly good study.
Why did the colonoscopy find nothing even though I have pain when passing stool?
Because a colonoscopy looks from the inside. Endometriosis lesions typically sit on the outside of the bowel wall and grow into the wall from there, often without ever reaching the mucosa. A normal colonoscopy therefore does not rule out endometriosis. It still makes sense, because it clarifies other causes, and with blood in the stool it belongs there anyway.
Is there a blood test for endometriosis?
None that could make or exclude the diagnosis. The ESHRE guideline explicitly recommends not using biomarkers in blood, endometrium, menstrual or uterine fluid for the diagnosis. A Cochrane review with 11 studies and 1339 participants could not assess a single one of these biomarkers in usable quality and advises against using non-invasive tests outside of research settings.
What does a raised CA-125 value tell me, and what does a normal one tell me?
A meta-analysis with 14 pooled studies and 2920 participants found a pooled specificity of 93 percent and a pooled sensitivity of 52 percent at a threshold of 30 U/ml. In moderate or severe endometriosis the sensitivity was 63 percent, in minimal disease only 24 percent. Translated, that means a high value can support the suspicion and shorten the path. A normal value is not reassuring.
What about the new saliva tests, and can I rely on them?
A prospective external validation with 971 patients reported an accuracy of 96.6 percent, a sensitivity of 97.3 percent and a specificity of 94.1 percent for a saliva miRNA signature in 2025. Those are strong numbers, and they come with three caveats: the study was funded by the manufacturer, the endometriosis prevalence in the group studied was 77 percent, and the methodological groundwork comes from the same team. The test is not anchored in the guidelines, and in Germany it is not a standard covered service. Promising, independent confirmation still pending.
When does an MRI make sense and when does it not?
As a second line, above all where deep infiltrating forms are suspected, where the ultrasound finding is unclear and for surgical planning. The Cochrane review found a sensitivity of 0.95 and a specificity of 0.91 for endometriomas, and 0.94 and 0.77 for deep infiltrating endometriosis, the latter from only 266 participants and with a very wide confidence interval of 0.44 to 1.00. As a first step the MRI is not intended, and it does not replace structured ultrasound.
What is the sliding sign, and why is it not checked everywhere?
In this dynamic examination the examiner watches whether the rectum glides smoothly over the back of the cervix and uterus under gentle pressure from the probe. If it glides, that speaks for a free pouch of Douglas. If it does not glide, that speaks for adhesions. It takes time, practice and a structured protocol. In a reproducibility study with 30 videos, agreement among four raters specialising in gynaecological ultrasound was at Cohen's kappa 0.630 to 0.927, while across all six raters it was 0.354 to 0.927.
How can I tell whether someone has experience with endometriosis ultrasound, and how do I ask?
You ask about the procedure, not about the skill. For example: will the posterior compartment be assessed in my case, will the sliding sign be checked, and will I get a structured report. In a prospective learning curve study with three trainees and 50 supervised examinations each, one of them in each case did not reach the competence threshold for bowel involvement or for the pouch of Douglas. So this examination is not trivial, and asking about it is not an expression of mistrust.
Which endometriosis symptoms occur outside the period?
Pain when passing stool, pain when urinating, deep pain during sex, cyclical back and leg pain, and pronounced exhaustion. In a case-control study at clinics and practices in Switzerland, Germany and Austria with 560 women with confirmed endometriosis and 560 controls, 50.7 percent reported frequent exhaustion compared with 22.4 percent in the control group, and this was independent of the stage of the disease.
Why is irritable bowel syndrome so often diagnosed first in endometriosis?
Because the symptoms overlap and because the abdomen is often louder than the pelvis. In a Danish cross-sectional survey the odds ratio for irritable bowel syndrome in endometriosis was 5.32, and in the subgroup without bowel involvement of the endometriosis it was even 6.54. In a Swedish population cohort there were no differences in gastrointestinal symptoms between endometriosis and irritable bowel syndrome. So the distinction cannot be made from the abdominal symptoms alone.
What belongs in a pain diary, and over how many cycles should I keep it?
At least two to three menstrual cycles, so that a pattern becomes visible and not just one bad month. What belongs in it: date and cycle day, pain intensity on a scale of 0 to 10, location of the pain, triggers, painkillers taken, bowel movements, urination, pain during sex, exhaustion, and days lost at school, university or work. The cycle day is the most important column, because it turns a list of complaints into a description of a pattern.
Why do I still have pain even though the findings are normal or the surgery went well?
Because pain does not only arise where something can be seen. In a prospective cohort with 239 patients, higher baseline scores on the Central Sensitization Inventory went along with stronger symptoms at follow-up, even after controlling for baseline pain scores. The German S2k guideline treats nociplastic pain mechanisms as a topic in their own right. This is not a statement that the pain is psychological. It describes a second mechanism that needs its own treatment.
Where to read on
Endometriosis, causes seen integratively
This article here describes the path to a diagnosis. The question of why the disease arises and which levels play a part is answered there.
If you are looking for the big pictureHormonal imbalance in women
The overview article of the cluster. It sorts out how the menstrual cycle, the thyroid, stress and metabolism hang together, and points to the matching deep dives.
If your cycle is hard and there may be other reasonsPMS and cycle symptoms
Not every difficult cycle goes back to endometriosis. What else can be behind it and which levers exist is covered there.
If you want to know which test whenTesting hormones, which test when
Blood, saliva, urine and the right day of the menstrual cycle. Useful, because the logic from this article carries over to hormone labs there.
If your abdomen plays the leading roleIrritable bowel syndrome, finding the causes
The most common diagnosis on the way to endometriosis. Both can exist side by side, and telling them apart is worth it in both directions.
If your digestion follows your cycleThe menstrual cycle and digestion
Why bowel movements and bloating change across the cycle. This exact pattern is the diagnostically important trail in endometriosis.
If your bleeding is heavy and you are constantly tiredIron deficiency and menstruation
Exhaustion belongs to the picture of endometriosis. But it often has a second cause that can be measured and treated.
If pain during sex is the topicLoss of libido in women
Deep dyspareunia changes closeness and relationships. That article is about the levels behind it, physical as well as psychological.
If chronic stress is part of itCortisol, stress and female hormones
Chronic stress changes pain processing and the menstrual cycle. That explains part of the symptoms without psychologising them.
If you want to know why I ask about environmental factorsXenoestrogens in everyday life
What hormonally active substances are, where they occur and how solid the data actually are. Calm and without scaremongering.
If mould appears in your storyZearalenone, the mycoestrogen
A mould toxin with documented oestrogen-like activity. The article shows how far the data reach and where they end.
If you want to know how such a test worksMeasuring heavy metals, blood or urine
The same question as with CA-125, only in a different field: what does a value say, and what can it not say.
If the pain staysUnderstanding endometriosis pain
Why the amount of lesions says little about pain intensity, and what central sensitisation means here.
If bleeding is the main problemRecognising adenomyosis
The endometriosis inside the uterine wall, its ultrasound features and how it differs from fibroids.
If you want to start with the plateEndometriosis and nutrition
What the studies on omega 3, gluten, dairy and red meat support, and why there is no endometriosis diet.
If the endometriosis trail interests youDioxins, PCBs and endometriosis
The 1993 monkey study, the Seveso cohort and what does and does not follow from them today.
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- What is well documented. The guideline statements from ESHRE 2022 and the German S2k version, the Cochrane numbers on imaging and the CA-125 meta-analysis. These statements carry the core of the article.
- What rests on a thin data base. The MRI values for deep infiltrating endometriosis come from 266 participants with a confidence interval of the specificity from 0.44 to 1.00. The accuracy figures for the sliding sign apply only after excluding the cases rated as uncertain. And the Cochrane review itself rates most of the included studies as methodologically poor.
- What is still open. The saliva miRNA test. The numbers are strong, the study was funded by the manufacturer, the prevalence in the group studied was 77 percent, and independent confirmation is still pending. Not anchored in any guideline, and in Germany not a standard covered service.
- What I deliberately do not claim. That the diagnostic delay is linked to the severity of the disease. That is clinically plausible and often asserted, but within the scope of this research it could not be supported by a verified source.
- How the numbers were handled. All values are taken verbatim from the abstracts or from the guideline texts. Nothing was converted and nothing rounded. The three figures on diagnostic delay stand side by side, because they measure different stretches.
- What this article is not. Not a set of instructions, not a recommendation about medicines, and not an invitation to change an ongoing treatment or to postpone a medically recommended investigation or operation. Endometriosis is a medical diagnosis, and the decisions around it belong in a consultation with an examination.