In humans, infertility is the inability to become pregnant after one year of intercourse without contraception involving a male and female partner.[2] There are many causes of infertility, including some that medical intervention can treat.[3] Estimates from 1997 suggest that worldwide about five percent of all heterosexual couples have an unresolved problem with infertility. Many more couples, however, experience involuntary childlessness for at least one year: estimates range from 12% to 28%.[4] Male infertility is responsible for 20–30% of infertility cases, while 20–35% are due to female infertility, and 25–40% are due to combined problems in both parts.[2][5] In 10–20% of cases, no cause is found.[5] The most common cause of female infertility is ovulatory problems, which generally manifest themselves by sparse or absent menstrual periods.[6] Male infertility is most commonly due to deficiencies in the semen, and semen quality is used as a surrogate measure of male fecundity.[7]
In the UK, previous NICE guidelines defined infertility as failure to conceive after regular unprotected sexual intercourse for two years in the absence of known reproductive pathology.[11] Updated NICE guidelines do not include a specific definition, but recommend that "A woman of reproductive age who has not conceived after 1 year of unprotected vaginal sexual intercourse, in the absence of any known cause of infertility, should be offered further clinical assessment and investigation along with her partner, with earlier referral to a specialist if the woman is over 36 years of age."[12]
The diagnosis is one of exclusion — that is, one which is made only after all the existing tests have been performed and their results found to be normal. This is why the frequency of this diagnosis will depend upon how many tests are done by the clinic — the fewer the tests, the more frequent this diagnosis. And the better the tests, the more likely you are getting a diagnosis instead of being told it's "unexplained."
Heavy, as in a pad and a tampon still doesn’t feel like enough. Certain medical conditions, like thyroid problems or kidney disease, can cause excessive menstrual bleeding, medications (such as anti-inflammatory drugs or anti-coagulants) may as well; or the reason may be a condition linked to infertility. In a normal menstrual cycle, the hormones estrogen and progesterone work together to regulate the buildup of the lining of the uterus—that’s the stuff that sheds during your period. But if, for example, your ovaries don’t release an egg, the dominoes are tipped: your body produces less progesterone, hormones become imbalanced, the lining in your uterus over-develops, and you end up bleeding extra heavily. Fibroids in your uterus can also cause heavier or longer-than-normal periods; some types of these benign tumors can block fallopian tubes or interfere with the implantation of a fertilized egg. Up to 10 percent of infertile women have fibroids, according to the American Society for Reproductive Medicine. If you soak through at least one pad or tampon an hour for more than a few hours, see your doctor.  This is the worst health advice gynecologists have ever heard.

Nadya Suleman came to international attention after having twelve embryos implanted, eight of which survived, resulting in eight newborns being added to her existing six-child family. The Medical Board of California sought to have fertility doctor Michael Kamrava, who treated Suleman, stripped of his licence. State officials allege that performing Suleman's procedure is evidence of unreasonable judgment, substandard care, and a lack of concern for the eight children she would conceive and the six she was already struggling to raise. On 1 June 2011 the Medical Board issued a ruling that Kamrava's medical licence be revoked effective 1 July 2011.[116][117] [118]
Disclaimer: The information you enter is not stored by CDC and is only used to estimate your chances of success. The IVF success estimator does not provide medical advice, diagnosis, or treatment. These estimates may not reflect your actual rates of success during ART treatment and are only being provided for informational purposes. Estimates are less reliable at certain ranges/values of age, weight, height, and previous pregnancy and ART experiences. Please see your doctor and/or healthcare provider for a personalized treatment plan that is best for you.
According to the data collected for 2014, these are the IVF success rates nationally, when using non-donor eggs, per egg retrieval. (These are not per cycle. In other words, these are the odds of a live birth after one egg retrieval, which may mean conception with fresh eggs/embryos in the cycle of the egg retrieval ​or after a frozen embryo transfer cycle in the following months.) 

Intercourse must take place frequently, particularly before and around the time of ovulation, and the couple must have been trying to conceive for at least one year (6 months if the woman is over 35 years old). Using these criteria, about 10-20% of all infertile couples have unexplained infertility. However, the percentage of couples classified as having unexplained infertility will depend upon the thoroughness of testing and the sophistication of medical technology. 
Other health related problems could also cause poor egg health, low ovarian reserve, or abnormal immunological responses, which can affect conception. Stress could also play a role. We all know that menstrual cycles can be altered during times of extreme duress- and this can be emotional, physical, or environmental stressors. In these instances, the first steps should be to avoid life stressors, maintain a healthy weight, routinely exercise, avoid smoking, and reduce alcohol intake, all of which may be contributing to unexplained infertility issues.
The Human Fertilisation and Embryology Authority said in September 2018 that parents who are limited to one cycle of IVF, or have to fund it themselves, are more likely choose to implant multiple embryos in the hope it increases the chances of pregnancy. This significantly increases the chance of multiple births and the associated poor outcomes, which would increase NHS costs. The president of the Royal College of Obstetricians and Gynaecologists said that funding 3 cycles was "the most important factor in maintaining low rates of multiple pregnancies and reduce(s) associated complications".[165]
The cost of an IUI is almost certainly less on a per cycle basis, but because IVF has much higher success rates and IUI is a poor option for some, the higher per cycle cost of IVF can actually be more affordable in the long run – in terms of the cost to bring home a baby.  Because most successful IUIs happen in the first three or four-cycle, it eventually becomes very expensive to bring home a baby with an IUI.
For couples who have no difficulty achieving a pregnancy, the natural chance of pregnancy per month of ovulation is largely dependent on the age of the woman. For women in their early 30s or younger, the natural pregnancy rate is about 20 to 25 percent per cycle. This drops off significantly through her mid-to late-30s; by her early 40s, the chance of pregnancy is about 5 percent per cycle. This age-related decrease is primarily due to a decline in the quality of the eggs within the ovaries.
A 2013 review and meta analysis of randomised controlled trials of acupuncture as an adjuvant therapy in IVF found no overall benefit, and concluded that an apparent benefit detected in a subset of published trials where the control group (those not using acupuncture) experienced a lower than average rate of pregnancy requires further study, due to the possibility of publication bias and other factors.[34]
Laboratories have developed grading methods to judge ovocyte and embryo quality. In order to optimise pregnancy rates, there is significant evidence that a morphological scoring system is the best strategy for the selection of embryos.[72] Since 2009 where the first time-lapse microscopy system for IVF was approved for clinical use,[73] morphokinetic scoring systems has shown to improve to pregnancy rates further.[74] However, when all different types of time-lapse embryo imaging devices, with or without morphokinetic scoring systems, are compared against conventional embryo assessment for IVF, there is insufficient evidence of a difference in live-birth, pregnancy, stillbirth or miscarriage to choose between them.[75] Active efforts to develop a more accurate embryo selection analysis based on Artificial Intelligence and Deep Learning are underway. Embryo Ranking Intelligent Classification Assistant (ERICA),[76] is a clear example. This Deep Learning software substitutes manual classifications with a ranking system based on an individual embryo's predicted genetic status in a non-invasive fashion.[77] Studies on this area are still pending and current feasibility studies support its potential.[78]

Today, with assisted-reproductive technology, the chance of successful treatment is very good. Intrauterine insemination with superovulation is the simplest approach since it increases the chances of the egg and sperm meeting, but some patients may also need GIFT and IVF. IVF can be helpful because it provides information about the sperm's fertilizing ability; GIFT, on the other hand, has a higher pregnancy rate and is applicable in these patients since they have normal fallopian tubes.


Assess your preconception prep. Have you been on top of the preconception game or are you just too busy for baby-planning activities like charting and timing baby-making sex (or any sex for that matter)? Given that you have a little one underfoot, it's understandable if you're more exhausted than ever. It’s not easy for wannabe second-time parents to devote as much time and energy to TTC as they likely did on the first go-around, but it would be helpful to take a step back (and a hard look) at what's going on. Are your cycles still regular, or have there been any changes that might be hurting your chances for conception success? Have you been able to pinpoint ovulation with accuracy, or are you just having sex whenever (which would make conception less likely)? Getting back on track with tracking your fertility signs may be enough to put you back in the game.
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Our specialized team of andrologists prepare each sperm sample with a procedure commonly known as "sperm washing" in one of our andrology laboratories. Sperm washing involves placing the sperm sample in a test tube and then a centrifuge, which results in the sperm collecting in a "pellet" at the bottom of the test tube. The andrologist removes the seminal fluid and places the fluid (media) above the sperm. The most active sperm will then swim up into the media. The final sample consists of the most active sperm concentrated in a small volume of media. A single IUI is usually performed when a patient is using fresh sperm. If a patient is using a frozen sperm sample, the clinician can likely perform one or two IUIs.

Heavy, as in a pad and a tampon still doesn’t feel like enough. Certain medical conditions, like thyroid problems or kidney disease, can cause excessive menstrual bleeding, medications (such as anti-inflammatory drugs or anti-coagulants) may as well; or the reason may be a condition linked to infertility. In a normal menstrual cycle, the hormones estrogen and progesterone work together to regulate the buildup of the lining of the uterus—that’s the stuff that sheds during your period. But if, for example, your ovaries don’t release an egg, the dominoes are tipped: your body produces less progesterone, hormones become imbalanced, the lining in your uterus over-develops, and you end up bleeding extra heavily. Fibroids in your uterus can also cause heavier or longer-than-normal periods; some types of these benign tumors can block fallopian tubes or interfere with the implantation of a fertilized egg. Up to 10 percent of infertile women have fibroids, according to the American Society for Reproductive Medicine. If you soak through at least one pad or tampon an hour for more than a few hours, see your doctor.  This is the worst health advice gynecologists have ever heard.


Availability of IVF in England is determined by Clinical commissioning groups. The National Institute for Health and Care Excellence recommends up to 3 cycles of treatment for women under 40 years old with minimal success conceiving after 2 years of unprotected sex. Cycles will not be continued for women who are older than 40 years old.[156] CCGs in Essex, Bedfordshire and Somerset have reduced funding to one cycle, or none, and it is expected that reductions will become more widespread. Funding may be available in "exceptional circumstances" – for example if a male partner has a transmittable infection or one partner is affected by cancer treatment. According to the campaign group Fertility Fairness at the end of 2014 every CCG in England was funding at least one cycle of IVF".[157] Prices paid by the NHS in England varied between under £3,000 to more than £6,000 in 2014/5.[158] In February 2013, the cost of implementing the NICE guidelines for IVF along with other treatments for infertility was projected to be £236,000 per year per 100,000 members of the population.[159]
During the second half of your menstrual cycle, the hormone progesterone kicks in to help prepare the lining of your uterus for a fertilized egg. If the egg isn't fertilized and doesn't implant, it disintegrates, progesterone levels fall, and about 12 to 16 days later, the egg -- along with blood and tissues from the lining of the uterus -- is shed from the body. That process is menstruation. It usually lasts 3 to 7 days.
• Women having irregular periods. Regular periods indicate that you are ovulating regularly. Eggs are produced through ovulation two weeks prior to the next period. Ovulation of the egg is essential for pregnancy, and any irregularity in this process leads to an inability to conceive. If you have irregular periods then it is better to get evaluated from a reproductive endocrinologist.
Post transfer – You’ll likely take progesterone and estrogen to improve implantation and pregnancy rates. If the transfer is successful, a blood pregnancy test will be positive in 10-14 days. From there, ultrasounds are used to ensure the implantation site as well as check for a heartbeat. The good news is that once a heartbeat is detected, the pregnancy has a 90-95% probability of the pregnancy resulting in a live birth.
The treatment options for unexplained infertility are several and the treatment results are promising. Expectant management can be recommended if the woman is under 28-30 years of age and the infertility duration is less than 2-3 years. In vitro fertilization (IVF) has revolutionized the treatment of infertile couples, as well as profoundly increasing the basic understanding of human reproduction. IVF can be used as both a diagnostic and a therapeutic tool in couples with unexplained infertility. The pregnancy rates with IVF are good, at 40% per treatment cycle. In addition, the outcome of pregnancies among women with unexplained infertility is generally comparable to that of spontaneous and other pregnancies using assisted reproductive technologies.

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Initial blood work, cycle tracking and fertility analysis is done. To begin IVF, your doctor or fertility specialist will evaluate your hormone levels and menstrual cycle to determine what medications and plan of action may be needed. You may also undergo a transvaginal ultrasound to examine your ovaries and reproductive system, ensuring that they are healthy.
Our team here at the Center for Human Reproduction has recently developed an infographic explaining one of the most common causes of female infertility: unexplained infertility. This diagnosis is given to 30% of infertility cases and yet, we believe it really is a non-diagnosis. In our clinical experience, with proper testing, up to 90% of unexplained infertility diagnoses can be attributed to treatable causes.
If a man and woman 35 or younger have had unprotected sex for at least 12 months (or six months if older than 35) without getting pregnant, they should suspect secondary infertility. This especially applies to women older than 30 who have experienced pelvic inflammatory disease, painful periods, irregular menstrual cycles or miscarriages, and to men with low sperm counts.

Availability of IVF in England is determined by Clinical commissioning groups. The National Institute for Health and Care Excellence recommends up to 3 cycles of treatment for women under 40 years old with minimal success conceiving after 2 years of unprotected sex. Cycles will not be continued for women who are older than 40 years old.[156] CCGs in Essex, Bedfordshire and Somerset have reduced funding to one cycle, or none, and it is expected that reductions will become more widespread. Funding may be available in "exceptional circumstances" – for example if a male partner has a transmittable infection or one partner is affected by cancer treatment. According to the campaign group Fertility Fairness at the end of 2014 every CCG in England was funding at least one cycle of IVF".[157] Prices paid by the NHS in England varied between under £3,000 to more than £6,000 in 2014/5.[158] In February 2013, the cost of implementing the NICE guidelines for IVF along with other treatments for infertility was projected to be £236,000 per year per 100,000 members of the population.[159]
IVF may be used to overcome female infertility when it is due to problems with the fallopian tubes, making in vivo fertilisation difficult. It can also assist in male infertility, in those cases where there is a defect in sperm quality; in such situations intracytoplasmic sperm injection (ICSI) may be used, where a sperm cell is injected directly into the egg cell. This is used when sperm has difficulty penetrating the egg. In these cases the partner's or a donor's sperm may be used. ICSI is also used when sperm numbers are very low. When indicated, the use of ICSI has been found to increase the success rates of IVF.
Monitoring of egg development is usually done with E2 and LH blood hormone tests and ultrasound scans of the ovaries to determine when the egg is mature. The ultrasound allows the physician to visualize the thickness of the uterine lining and the ovaries, more specifically the number of follicles within them. The bloodwork shows the trend of pre- to post-stimulation hormone levels; increased levels of estrogen indicate follicular development.
Another major cause of infertility in women may be the inability to ovulate. Malformation of the eggs themselves may complicate conception. For example, polycystic ovarian syndrome is when the eggs only partially develop within the ovary and there is an excess of male hormones. Some women are infertile because their ovaries do not mature and release eggs. In this case synthetic FSH by injection or Clomid (Clomiphene citrate) via a pill can be given to stimulate follicles to mature in the ovaries.
^ Manheimer E, van der Windt D, Cheng K, Stafford K, Liu J, Tierney J, Lao L, Berman BM, Langenberg P, Bouter LM (2013). "The effects of acupuncture on rates of clinical pregnancy among women undergoing in vitro fertilization: a systematic review and meta-analysis". Human Reproduction Update. 19 (6): 696–713. doi:10.1093/humupd/dmt026. PMC 3796945. PMID 23814102.
While PGD was originally designed to screen for embryos carrying hereditary genetic diseases, the method has been applied to select features that are unrelated to diseases, thus raising ethical questions. Examples of such cases include the selection of embryos based on histocompatibility (HLA) for the donation of tissues to a sick family member, the diagnosis of genetic susceptibility to disease, and sex selection.[97]

Gonadotropins are another drug used to trigger ovulation. Gonadotropins are used if other drugs are not successful or if many eggs are needed for infertility treatments. Gonadotropins are given in a series of shots early in the menstrual cycle. Blood tests and ultrasound exams are used to track the development of the follicles. When test results show that the follicles have reached a certain size, another drug may be given to signal a follicle to release its matured egg.

The ultrasound is to check the size of your ovaries. Your doctor will also look for ovarian cysts. If there are cysts, your doctor will decide how to deal with them. Sometimes your doctor will just delay treatment for a week. Most cysts resolve on their own with time. In other cases, your doctor may aspirate the cyst (suck out the fluid) with a needle.


^ Hozyasz, K (March 2001). "Coeliac disease and problems associated with reproduction". Ginekol Pol. 72 (3): 173–9. PMID 11398587. Coeliac men may have reversible infertility, and as in women, if gastrointestinal symptoms are mild or absent the diagnosis may be missed. It is important to make diagnosis because the giving of gluten free diet may result in conception and favourable outcome of pregnancy.
^ Hozyasz, K (March 2001). "Coeliac disease and problems associated with reproduction". Ginekol Pol. 72 (3): 173–9. PMID 11398587. Coeliac men may have reversible infertility, and as in women, if gastrointestinal symptoms are mild or absent the diagnosis may be missed. It is important to make diagnosis because the giving of gluten free diet may result in conception and favourable outcome of pregnancy.
^ GBD 2015 Disease and Injury Incidence and Prevalence, Collaborators. (8 October 2016). "Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015". Lancet. 388 (10053): 1545–1602. doi:10.1016/S0140-6736(16)31678-6. PMC 5055577. PMID 27733282.

^ Siristatidis C, Sergentanis TN, Kanavidis P, Trivella M, Sotiraki M, Mavromatis I, Psaltopoulou T, Skalkidou A, Petridou ET (2012). "Controlled ovarian hyperstimulation for IVF: impact on ovarian, endometrial and cervical cancer—a systematic review and meta-analysis". Human Reproduction Update. 19 (2): 105–23. doi:10.1093/humupd/dms051. PMID 23255514.
A woman's age is a major factor in the success of IVF for any couple. For instance, a woman who is under age 35 and undergoes IVF has a 39.6% chance of having a baby, while a woman over age 40 has an 11.5% chance. However, the CDC recently found that the success rate is increasing in every age group as the techniques are refined and doctors become more experienced.
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