The copper IUD is not just plastic with metal.
It is a biological decision.
Why so many women quietly feel worse with the copper IUD, what the evidence honestly shows, and which paths out of the silent malaise can help.
Some exhaustions have a name that never shows up in the lab report. You are more tired than before, your head feels foggy, your hair thins, your period lasts longer, iron is low, mood tips faster. You search for the cause. You find thirty possibilities. Maybe one of them sits in your pelvis. Maybe not. But the question deserves a serious consultation, not a dismissal.
How this question usually shows up in the consultation
There is a pattern I meet again and again. A woman describes that she has been more tired than she used to be. Her head feels foggy. Her period lasts longer and has become heavier. The results she brings along look unremarkable. She cannot pin down what is different, but she notices that something is. I deliberately describe no individual case here, no lab values and no course of treatment. A single story would tell you nothing about yourself anyway. What I can describe is the approach: listen, measure properly, place the evidence honestly, and then decide together.
Some complaints with an IUD in place do not belong in a blog article, and not on the next free appointment either. Severe or sudden lower abdominal pain, fever, foul-smelling discharge, very heavy bleeding with dizziness, threads you can no longer feel, or a positive pregnancy test with the IUD in place all need a prompt medical examination. Pelvic inflammatory disease, displacement or perforation, or an ectopic pregnancy can be behind them. With severe pain and circulatory symptoms, call the emergency number, 112 in Germany, and do not wait. One more thing belongs here: if your mood stays low over weeks, that needs medical assessment regardless of any iron value. If you have thoughts of taking your own life, Telefonseelsorge is available free of charge around the clock on 0800 111 0 111 in Germany. In an acute crisis, call the emergency number, 112.
What the IUD does in the body.
The copper IUD is a hormone-free, highly effective contraceptive, and for many women it is a good choice. It prevents pregnancy very reliably and lasts up to ten years. That is the bright side, and it is real.
The other side is plainly stated in the mainstream literature. In everyday practice it slips into the background more easily, because it is harder to pin down than a number for reliability. Sterile inflammation means inflammation without detectable pathogens. And that is the assumed mechanism of the copper IUD.
The IUD is thought to work through inflammation
An official review in Human Reproduction Update puts it cautiously, and the wording matters, because it says "may be": "The contraceptive effects of IUDs may be due to a sterile inflammatory reaction in the endometrial cavity which interferes with sperm function so that fertilization is less likely to occur." Over five years, pregnancy occurs in fewer than two of 100 insertions. The review also reports removal rates of 10 percent in the first year and up to 50 percent within five years. That is the overall removal rate, and bleeding and pain are named there as the most common, not the only, reasons. The review covers intrauterine devices in general, not only the copper version.
ESHRE Capri Workshop Group (coordinated by Crosignani PG), Hum Reprod Update 2008;14(3):197-208. doi.org/10.1093/humupd/dmn003
Let that number sink in. Over five years, up to half of the devices are removed according to this review, and about one in ten in the first year. Bleeding and pain are the most commonly named reasons, but not the only ones. The range is wide, and the upper figure is the worst case from this review. But it belongs in the counselling conversation.
The IUD is not just a piece of plastic with metal that sits passively in your body. The assumed mechanism is a local inflammatory reaction in the uterus, and it runs for the whole time the device is in place. For most women that is well tolerated. For a subgroup it is not, and that subgroup deserves a serious work-up.
What happens in the tissue and in the system.
In functional medicine and clinical psychoneuroimmunology we look at the IUD through four lenses at once. What happens locally in the uterus, what happens in the micronutrient household, what happens in the nervous system, and what happens in the metabolic-hormonal axis.
The inflammation is the intended mechanism, and it may not always stay fully local. Studies in women with copper IUDs show elevated local vaginal cytokines, a shift toward cytokine-producing anaerobes in the microbiome, and a different endometrial cytokine profile than in women without an IUD. With long use, plasma markers such as ceruloplasmin and liver enzymes can also be mildly elevated.
Copper does reach the bloodstream, in moderate amounts. A 2014 pharmacokinetic study showed a statistically significant rise in serum copper after three months of use, remaining in the normal range but measurable. Another, very small study showed that after more than two consecutive years of use, markers of oxidative stress such as TBARS can measurably rise. What is true for you can be clarified by measuring serum copper, ceruloplasmin and calculated free copper.
The iron deficiency trail is, in my view, the most underestimated path. Older measurement series with objectively determined blood loss found a mean increase of about 18 to 19 millilitres per cycle for the Copper 7, the copper device common at the time, measured in women with and without a previous birth (Guillebaud and colleagues, Lancet 1976). How large the increase is with today's models is not consistently quantified. In women with heavier bleeding, anemia can be considerably more common, in older work by a multiple. What matters to me is the order: before we attribute heavier bleeding to the IUD, it belongs in a gynecological work-up. Fibroids, polyps, adenomyosis, endometrial changes, a thyroid disorder and above all inherited bleeding disorders such as von Willebrand disease or a platelet function disorder can be behind it. Von Willebrand disease in particular can go unrecognised in women for years. Blood-thinning medication also belongs on the list, for instance acetylsalicylic acid (marketed among others as Aspirin), phenprocoumon (Marcumar) or the direct oral anticoagulants such as rivaroxaban and apixaban. Apart from low-dose acetylsalicylic acid these are prescription-only, and you must never stop any of them on your own because of heavy bleeding, since abrupt discontinuation can carry a risk of thrombosis or embolism. That always belongs in the hands of the prescribing physician. Only once those causes have been worked up does the question of what the IUD contributes make sense. And iron deficiency below overt anemia can already come with fatigue, brain fog, low mood, hair loss, and cold hands.
The copper-zinc balance can shift. The two trace elements are in part antagonistic. Zinc deficiency can show as brittle nails, hair loss, slower wound healing or more frequent infections. The immune system also needs zinc for a balanced T-cell response. How strongly the IUD itself shifts this balance is not conclusively settled. Honesty requires this too: the study that shows the rise in serum copper found a clear rise in zinc over the same period. That argues against a simple copper-zinc shift.
The nervous system participates. Chronic low-grade discomfort can hold the autonomic nervous system in sympathetic mode, that can drive cortisol, and that in turn can disturb sleep, amplify pain perception and slow mucosal healing. This is a physiological line of reasoning, not something measured on the IUD in a study.
PharmacokineticsSerum copper rises significantly under the copper IUD
In around a hundred women using the TCu-380A IUD, serum copper rose significantly from 160.40 to 170.22 micrograms per deciliter after three months, with p = 0.034. Values stayed within normal range, but the rise was measurable. The same paper found a rise in zinc from 94.61 to 107.67 micrograms per deciliter over the same period, with p below 0.001. The authors explicitly call this unexpected. So this finding does not support a simple copper-zinc shift.
Imani S et al., Eur J Contracept Reprod Health Care 2014;19(1):45-50. doi.org/10.3109/13625187.2013.856404
Oxidative stressAfter more than two years, stress markers can rise quietly
In 35 women using the TCu-380A IUD for more than two consecutive years, compared with 39 women without a device, plasma copper was elevated, along with time-dependent rises in TBARS as a marker of oxidative stress, ceruloplasmin and metallothioneins, and liver enzymes. This is not overt toxicity. It is a quiet, subclinical trace, measured in a very small group. That sample size is not enough for a general statement.
Arnal N, de Alaniz MJT, Marra CA, Toxicol Lett 2010;192(3):373-378. doi.org/10.1016/j.toxlet.2009.11.012
The simplest explanation is often the right one.
When I see a woman with a copper IUD and chronic exhaustion, my first suspicion is not copper poisoning. My first suspicion is iron deficiency. In my consultation I meet it regularly. That is my observation of the women who come to me, not a statistic and not a success rate, and my consultation is not a representative sample.
CohortFerritin falls over twelve months, the blood count notices later
In one study, 47 women were followed before and for one year after IUD insertion. In 44 of them, that is 94 percent, menstrual blood loss increased. Before insertion, 19 percent had ferritin in the deficiency range below 16 micrograms per litre. After one year, 45 percent did. Hemoglobin and the red cell indices declined slowly as well, but they flagged the deficiency much later than ferritin did. So even without dramatic hemoglobin drops, iron stores can quietly run dry under the IUD. For context: this is a 1979 cohort using the devices common at the time, and the rise in bleeding depended there on the surface area of the device. As evidence for what happens with today's devices it is only partly transferable.
Guillebaud J, Barnett MD, Gordon YB, Br J Obstet Gynaecol 1979;86(1):51-55. doi.org/10.1111/j.1471-0528.1979.tb10684.x
Iron deficiency without anemia can already be a burden
A recent review summarises: heavy menstrual bleeding can be a major contributor to iron deficiency and iron deficiency anemia. Iron deficiency without manifest anemia can already impair cognition and quality of life. The review also points out that an increasing body of evidence suggests iron deficiency, even in early pregnancy, may adversely affect fetal neurodevelopment. That is an argument for keeping iron status in view early when planning a pregnancy, and not a statement about your individual case. The second emphasis of this paper matters just as much: it comes from haemostasis medicine and explicitly aims at considering and working up a bleeding disorder in heavy menstrual bleeding.
Munro MG et al., Am J Obstet Gynecol 2023;229(1):1-9. doi.org/10.1016/j.ajog.2023.01.017
A ferritin below 30 micrograms per liter can already come with symptoms even when hemoglobin still looks normal. There is a genuine professional grey zone here. Depending on the laboratory, the ferritin reference range starts at around 15 micrograms per liter. A value just above that is therefore formally within the reference range, and whoever reads it that way is reading the lab sheet correctly. At which value an individual woman develops symptoms is a different question, and the literature still discusses it differently. So I look at the value together with the symptoms, not at the value alone.
What the literature does NOT show.
For you to trust this article, I must also say where the evidence is thin. Otherwise this would not be a medical text but an anti-IUD pamphlet, and that is not my intent.
Fairness also means the opposite of what you usually read in advice pieces. In a large study of almost two thousand first-time users, bleeding and pain complaints during the period on average decreased rather than increased over the first year. Complaints between periods stayed equally frequent but lasted longer. And the study that shows the rise in serum copper found a simultaneous rise in zinc, which argues against a simple copper-zinc shift. The question is more open than it is often made out to be.
Described in studies
Local endometrial and vaginal inflammation. Increased menstrual bleeding, in older measurement series by about 18 to 19 millilitres per cycle on average. Considerably more frequent anemia with heavier bleeding. Moderate systemic copper rise. Subclinical oxidative stress after long use. For the last two points the data come from single studies with small samples, not from large cohorts.
Mechanism plausible, evidence thin
Mast cell activation by copper. Autoimmune flare from IUD. Direct depression from IUD independent of iron deficiency. ATP7B heterozygosity as a sensitivity factor. There are case reports and mechanistic arguments here, but no large cohort data.
Important nuanceTrue copper allergy is rarer than anecdotally told
In one clinic, 1888 IUDs were inserted within six months. In ten women the device had to be removed because of skin complaints. Four of them were tested allergologically together with three further patients, so not all ten. None of the women tested was allergic to copper. One reacted to nickel.
Frentz G, Teilum D, Acta Derm Venereol 1980;60(1):69-71. PMID 6153839
A second study examined 49 women with complaints under an IUD allergologically. Nine reacted within 24 hours to a one percent copper sulphate solution, six still after 72 hours. In only one woman could a very weak copper allergy be confirmed. One side finding is telling: 38 of the 49 women had a nickel allergy, and eight of the nine women who reacted were nickel-sensitised. True copper contact allergy therefore seems to be rare. What may play a role for many women is the chain of inflammation, iron deficiency, and copper-zinc shift, rather than a classic allergic reaction.
Hausen BM, Hohlbaum W, Dtsch Med Wochenschr 1986;111(26):1016-21. doi.org/10.1055/s-2008-1068575
This honest line matters because it shows: your symptoms are not imagined, but they often have a more pragmatic explanation than "copper is poison for me". It is mostly inflammation plus iron deficiency plus hormonal-autonomic dysregulation. And that is something we can measure and treat.
Copper in the warmth organ.
In anthroposophic tradition, copper is a warmth metal, with Venus resonance, connected to the female pole of the human being. Copper ointments are used therapeutically, for instance for acute exhaustion or spasm tendency, short-term and in appropriate form. The experience of this tradition is: copper at the right place, in the right form, short-term, can be warming and strengthening. Copper at the wrong place, in the wrong form, for years, can do the opposite.
A copper IUD, from this perspective, is a continuous, local copper stimulation at the center of the female warmth structure, over five, eight, sometimes ten years. This language has no RCT evidence, it is clinical tradition. But it is a language in which many women recognise their own experience for the first time. That does not make it truer than other approaches, but it makes it usable.
You are not imagining things if you sense that something inside you is quieter than before. It is worth staying with it until someone looks at it with you all the way through.
Where my stance on this question comes from.
I allow myself a personal note here, because it contributes to the clarity with which I treat this question in my consultation.
I was myself conceived while contraception was in use. That shapes my stance to this day: contraception is a very good probability, not a biological guarantee. That holds for the IUD as for every other method. And I am glad about it.
This gives me a certain stance as a doctor. I take the IUD seriously as a contraceptive method, and I also take seriously every woman who says she feels worse with it. I take seriously the fact that a subgroup of women have it removed within five years. And I take iron deficiency seriously, because I see how quickly it builds and how deep it reaches.
What you can do today.
You do not need an immediate decision. You need an order that holds.
The diagnostic line
- Iron status done right. Ferritin, transferrin, transferrin saturation, soluble transferrin receptor, reticulocyte hemoglobin, hemoglobin, MCV. Not only Hb.
- Copper and zinc serum, plus ceruloplasmin. From these you calculate free, non-ceruloplasmin-bound copper.
- hs-CRP. Often mildly elevated in silent inflammation. Important for interpretation: ferritin is also an acute phase protein. With inflammation it can read falsely normal or falsely high and thereby mask an iron deficiency. So ferritin always belongs alongside CRP and transferrin saturation, never on its own.
- Full thyroid panel. TSH, fT3, fT4, TPO antibodies. Iron deficiency and Hashimoto frequently overlap.
- Vitamin D, active B12, folate. Vitamin B12 and folate contribute to the reduction of tiredness and fatigue, vitamin D to the normal function of the immune system.
The rebuilding line, with or without IUD
These are talking points for a consultation, not instructions for self-medication. What fits you, and at what dose, belongs in a conversation after the labs. In pregnancy and while breastfeeding that goes double: none of the items named here is your decision alone, and the dosing differs fundamentally. In that case talk to your physician first.
- Iron supplementation. Whether it makes sense, and from which ferritin, is decided individually from findings and symptoms, not by a fixed number. An iron infusion is not a wellness item. It requires a confirmed indication and belongs in medical hands because of possible hypersensitivity reactions.
- Zinc. Usually given for a limited period and then reassessed. Zinc over longer stretches can affect copper balance, so only with lab monitoring and medical guidance, not indefinitely on suspicion. The European authority names an upper level of 25 milligrams per day for long-term intake from supplements. Zinc can also reduce the absorption of antibiotics from the tetracycline and quinolone groups, so those need to be taken at a distance in time.
- Vitamin C. Vitamin C contributes to the normal function of the immune system and increases iron absorption from plant foods. That is exactly why it is not harmless for everyone: with haemochromatosis or any other iron overload, deliberately increasing iron absorption is not wanted. With kidney stones or impaired kidney function, a higher intake can raise the oxalate load. So the amount belongs in a conversation, not in a shopping basket.
- Glutathione or N-acetylcysteine. These substances are much discussed in connection with oxidative stress. There are no solid studies on this particular question, and no authorised health claims exist for them. I name them here only because you will come across them online, not as a recommendation. N-acetylcysteine can trigger bronchospasm in bronchial asthma and can amplify the effect of nitrates. With asthma or nitrate therapy this belongs in a medical conversation first.
- Magnesium. As glycinate or citrate. Magnesium contributes to normal muscle function and to the normal function of the nervous system. Whether it personally helps you with tension or sleep is individual and can only be tried out. With impaired kidney function magnesium can accumulate, so intake belongs in a medical conversation. Too much at once usually causes loose stools, that is the usual first signal.
The anthroposophic complement
- Milk thistle and birch leaves as tea are used in clinical tradition to support liver and kidneys, and there is no solid study basis for it. Birch leaves are not suitable where fluid retention is due to heart or kidney insufficiency. Milk thistle can affect the metabolism of medicines and is a composite plant, which matters with a composite-family allergy.
- Bryophyllum preparations are used in anthroposophic tradition for inner restlessness, clinical tradition without a solid study basis. Choice and form belong in a medical conversation.
- Warm abdominal compresses with yarrow oil in the evening, clinical tradition to calm the warmth structure of the pelvis. Yarrow is also a composite plant and can sensitise the skin and make it more light-sensitive. With a known composite-family allergy, better to leave it out, otherwise test on a small patch of skin first.
Contraceptive alternatives
- Symptothermal Sensiplan method. In the large German observational study of 900 women and 17,638 cycles, the rate of unintended pregnancy was 0.6 per 100 women per 13 cycles when there was no unprotected intercourse in the fertile time. In the cohort overall, that is the way couples actually use the method in daily life, it was 1.8 per 100 women per 13 cycles. Other surveys of fertility awareness methods report considerably higher rates in everyday use. The method needs a learning period of two to three cycles and daily discipline. A switch must not open a contraceptive gap.
- Barrier methods. Diaphragm with gel, condom.
- Definitive solutions. Vasectomy is a minor surgical procedure in the man, tubal ligation a larger one in the woman. Both should be regarded as permanent, and reversal does not reliably restore fertility. Both are options only for couples whose family planning is firmly complete, and like any procedure they carry their own risks.
- Hormonal IUD. Reduces bleeding significantly but has its own side-effect profile with local and systemic hormonal effects.
Removing a copper IUD is not an emergency decision and not a blanket recommendation. It is an individual decision after diagnosis, history-taking, and informed consent. If symptoms clearly map to the IUD and the labs offer a plausible mechanistic explanation, an accompanied removal can be sensible. One practical point: a copper IUD cannot simply be removed after unprotected intercourse in the current cycle, because a fertilisation that is already possible would then no longer be prevented. So the appointment belongs planned according to your cycle and agreed together with seamless follow-on contraception.
Six steps you can take now
Each a puzzle piece. Together they paint the picture.
- Write down what has changed. Date of insertion, symptoms over time, period duration, energy, mood, sleep, hair, skin.
- Get the labs done. Iron panel, copper-zinc-ceruloplasmin, hs-CRP, thyroid, vitamin D, active B12.
- Talk to your gynecologist. Share your observations, ask for an open discussion of the evidence.
- Rebuild the stores. Iron, zinc, vitamin D, B12. A full tank lets you make the IUD decision clearly.
- Learn a second contraceptive option. A Sensiplan course over two cycles so you do not fall into a gap if you decide to remove.
- Get accompaniment. A consultation where you can describe your observations without rushing and where the evidence is discussed openly. That is exactly my work, and I am glad to do it together with your gynecologist.
Your perception is your information.
When you have felt that something is different since copper IUD insertion, without being able to name it, then your perception is your most important information. It is not proof, but it is a beginning. It deserves serious diagnostics, an open conversation, and a path that fits you.
The IUD is a legitimate contraceptive method. For many women it is a good choice. For a subgroup it can slowly become a burden. The possible mechanisms behind that are better described today than ten years ago, but they are not conclusively settled.
True freedom is not perfect contraception at any cost. True freedom is a choice your whole system can live with.
Common questions from my consultation
Does copper from the IUD enter the bloodstream?
Modestly, yes. A 2014 study in around a hundred women showed a statistically significant rise in serum copper after three months of use. The values stayed within the normal range. The same study also found a rise in zinc over the same period.
Does the copper IUD cause inflammation?
A local inflammatory reaction is the assumed mechanism. The 2008 mainstream review names a sterile inflammatory reaction as the likely contraceptive effect, and states it explicitly as a possibility rather than a proven chain.
Does the IUD cause iron deficiency?
It can contribute. Older measurement series found a mean increase in menstrual blood loss of about 18 to 19 millilitres per cycle with the copper devices of that generation. With heavier bleeding, anemia can be considerably more common. The order matters: heavier bleeding belongs in a gynecological work-up first, among other things for fibroids, polyps, adenomyosis and bleeding disorders.
Can the IUD make me tired or depressed?
Direct randomised trials are lacking, so no cause-and-effect statement is possible. The path through iron deficiency to fatigue and low mood is well studied. A shift in the copper-zinc balance is described, but its clinical significance is open. A persistently low mood needs medical assessment regardless of your iron status.
Should I have my copper IUD removed?
That is an individual consultation decision, not a blanket recommendation. If the work-up shows iron deficiency or raised oxidative stress, an accompanied removal can be sensible. The timing should be planned according to your cycle so that no contraceptive gap opens.
What hormone-free alternatives exist?
The symptothermal Sensiplan method was studied in a large German observational cohort. There the rate of unintended pregnancy was 0.6 per 100 women per 13 cycles when there was no unprotected intercourse in the fertile time, and 1.8 per 100 women in the cohort overall. Used inconsistently, the rate is considerably higher. Plus diaphragm with gel and condom. Vasectomy and tubal ligation should be regarded as permanent.
What to do after removal?
We look at the findings first and then rebuild stores in a targeted way, iron above all. What else makes sense, such as zinc for a limited period, is decided individually and with lab monitoring. Alongside that, the simple things: movement and sleep.
Sources
- ESHRE Capri Workshop Group (coordinated by Crosignani PG). Intrauterine devices and intrauterine systems. Hum Reprod Update 2008;14(3):197-208. doi.org/10.1093/humupd/dmn003
- Hubacher D, Chen PL, Park S. Side effects from the copper IUD: do they decrease over time? Contraception 2009;79(5):356-62. doi.org/10.1016/j.contraception.2008.11.012
- Hubacher D et al. RCT of prophylactic ibuprofen for IUD side effects. Hum Reprod 2006.
- Cohen BJ. Anemia and menstrual blood loss. Obstet Gynecol Surv 1980.
- Guillebaud J, Bonnar J, Morehead J, Matthews A. Menstrual blood-loss with intrauterine devices. Lancet 1976;1(7956):387-390. doi.org/10.1016/s0140-6736(76)90216-6
- Guillebaud J, Barnett MD, Gordon YB. Plasma ferritin levels as an index of iron deficiency in women using intrauterine devices. Br J Obstet Gynaecol 1979;86(1):51-55. doi.org/10.1111/j.1471-0528.1979.tb10684.x
- Munro MG, Mast AE, Powers JM, et al. The relationship between heavy menstrual bleeding, iron deficiency, and iron deficiency anemia. Am J Obstet Gynecol 2023;229(1):1-9. doi.org/10.1016/j.ajog.2023.01.017
- Imani S, Moghaddam-Banaem L, Roudbar-Mohammadi S, Asghari-Jafarabadi M. Changes in copper and zinc serum levels in women wearing a copper TCu-380A intrauterine device. Eur J Contracept Reprod Health Care 2014;19(1):45-50. doi.org/10.3109/13625187.2013.856404
- Arnal N, de Alaniz MJT, Marra CA. Alterations in copper homeostasis and oxidative stress biomarkers in women using the intrauterine device TCu380A. Toxicol Lett 2010;192(3):373-378. doi.org/10.1016/j.toxlet.2009.11.012
- Brown BP, Feng C, Tanko RF, et al. Copper intrauterine device increases vaginal concentrations of inflammatory anaerobes and depletes lactobacilli compared to hormonal options in a randomized trial. Nat Commun 2023;14:499. doi.org/10.1038/s41467-023-36002-4
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- Siotto M et al. Serum ceruloplasmin specific activity and Alzheimer risk. J Alzheimers Dis 2016.
- Quan Z et al. Mineral elements and depression. Int J Mol Sci 2023.
- Majewska Z et al. Mineral homeostasis and depression. Int J Mol Sci 2025.
- D'Ambrosio FP et al. Systemic contact dermatitis to copper IUD. Allergy 1996. doi.org/10.1111/j.1398-9995.1996.tb04688.x
- Frentz G, Teilum D. Cutaneous eruptions and intrauterine contraceptive copper device. Acta Derm Venereol 1980;60(1):69-71. PMID 6153839
- Hausen BM, Hohlbaum W. Verursachen kupferhaltige Intrauterinpessare eine Kontaktallergie? Dtsch Med Wochenschr 1986;111(26):1016-21. doi.org/10.1055/s-2008-1068575
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- Pelikan W. The Seven Metals. Anthroposophic tradition.
- Frank-Herrmann P, Heil J, Gnoth C, Toledo E, Baur S, Pyper C, Jenetzky E, Strowitzki T, Freundl G. The effectiveness of a fertility awareness based method to avoid pregnancy in relation to a couple's sexual behaviour during the fertile time: a prospective longitudinal study. Hum Reprod 2007;22(5):1310-1319. doi.org/10.1093/humrep/dem003