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.
Intrauterine insemination is the process whereby a clinician will place a concentrated specimen of sperm in your uterus. For this procedure, he or she will insert a speculum into your vagina in order to better visualize your cervix. He or she will then pass a soft, thin catheter through the cervix opening and into the uterus. The clinician will introduce the washed sperm into the uterus through this catheter. The procedure is done in our office and takes 1 to 2 minutes. It is not painful and does not require anesthesia. You can return to normal daily activities immediately after an IUI.
In order for pregnancy to happen, sperm has to meet the egg. This normally takes place at the end of the fallopian tube, and this is called fertilization. There are a number of obstacles that can prevent this from happening, and the process itself even in healthy young fertile women is very complex- hence the low pregnancy rate each month. Obstacles such as cycle timing, low sperm count, poor sperm motility, blocked fallopian tubes, or endometriosis must be overcome to achieve a pregnancy. Timing is often the most common obstacle to conception. What does it mean for you when common causes of infertility are ruled out and you’re told you have unexplained infertility? It should mean a time of hope.
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]

Ovarian stimulation – You’ll take stimulation medications to increases both the quantity and quality of eggs. This usually begins during days 2-4 of your cycle and continues for around ten days. You’ll be closely monitored during this time to track your uterine lining, follicular development, and hormone levels. Once the follicles are optimal size, a trigger medication is given to fully mature the eggs.
When the ovarian follicles have reached a certain degree of development, induction of final oocyte maturation is performed, generally by an injection of human chorionic gonadotropin (hCG). Commonly, this is known as the "trigger shot."[67] hCG acts as an analogue of luteinising hormone, and ovulation would occur between 38 and 40 hours after a single HCG injection,[68] but the egg retrieval is performed at a time usually between 34 and 36 hours after hCG injection, that is, just prior to when the follicles would rupture. This avails for scheduling the egg retrieval procedure at a time where the eggs are fully mature. HCG injection confers a risk of ovarian hyperstimulation syndrome. Using a GnRH agonist instead of hCG eliminates most of the risk of ovarian hyperstimulation syndrome, but with a reduced delivery rate if the embryos are transferred fresh.[69] For this reason, many centers will freeze all oocytes or embryos following agonist trigger.
Anger, sadness, and anxiety are common among parents struggling to expand their family. "Having a child already doesn't make going through infertility any easier," says Alice D. Domar, Ph.D., executive director of the Domar Center for Mind/Body Health, in Waltham, Massachusetts, and author of Conquering Infertility. Meeting with a mental-health professional or seeking out blogs and online groups for secondary infertility can help. The website of  the National Infertility Association, resolve.org, is a good place to start.
IUI: An IUI can be done with no medications or a number of different medications to help develop and ovulate one or two eggs. Around day 14 of a woman’s cycle, the insemination takes place which deposits sperm inside the uterus. This greatly increases the number of sperm at the junction of the uterus and fallopian tubes, the distance they have to swim to meet the egg, and thus increases the chances of natural conception for many people.
By 2012 Costa Rica was the only country in the world with a complete ban on IVF technology, it having been ruled unconstitutional by the nation's Supreme Court because it "violated life."[177] Costa Rica had been the only country in the western hemisphere that forbade IVF. A law project sent reluctantly by the government of President Laura Chinchilla was rejected by parliament. President Chinchilla has not publicly stated her position on the question of IVF. However, given the massive influence of the Catholic Church in her government any change in the status quo seems very unlikely.[178][179] In spite of Costa Rican government and strong religious opposition, the IVF ban has been struck down by the Inter-American Court of Human Rights in a decision of 20 December 2012.[180] The court said that a long-standing Costa Rican guarantee of protection for every human embryo violated the reproductive freedom of infertile couples because it prohibited them from using IVF, which often involves the disposal of embryos not implanted in a patient's uterus.[181] On 10 September 2015, President Luis Guillermo Solís signed a decree legalising in-vitro fertilisation. The decree was added to the country's official gazette on 11 September. Opponents of the practice have since filed a lawsuit before the country's Constitutional Court.[182]
The Fallopian tubes are the site for fertilization before the embryo makes its way to the uterine cavity for implantation. If the Fallopian tubes are damaged, fertilization may not occur. If one Fallopian tube is blocked, it may be due to inherent disease involving both Fallopian tubes; even if the other Fallopian tube is open, it may not be able to provide the appropriate nurturing environment for fertilization and early embryo growth to take place.
In the US, up to 20% of infertile couples have unexplained infertility. In these cases abnormalities are likely to be present but not detected by current methods. Possible problems could be that the egg is not released at the optimum time for fertilization, that it may not enter the fallopian tube, sperm may not be able to reach the egg, fertilization may fail to occur, transport of the zygote may be disturbed, or implantation fails. It is increasingly recognized that egg quality is of critical importance and women of advanced maternal age have eggs of reduced capacity for normal and successful fertilization. Also, polymorphisms in folate pathway genes could be one reason for fertility complications in some women with unexplained infertility.[59] However, a growing body of evidence suggests that epigenetic modifications in sperm may be partially responsible.[60][61]

Generally, the best chance of pregnancy is when sex happens 1-2 days before ovulation. If you have a regular 28-day cycle, count back 14 days from when you expect your next period to start. Plan on having sex every other day around that time -- say, days 12 and 14.  Keep in mind that having sex every day may lower a man's sperm count. Your cycle may be longer or shorter, so an online ovulation calculator may help you figure out the likely day.


Amongst these two patient populations (which we’ll refer to now as PCOS), IUI with clomid and letrozole generally shows no improvement versus when these drugs are taken without IUI. When IUI is coupled with gonadotropins, success rates reach 14 - 26% per cycle, which is higher than almost any other patient class, but still pales in comparison to IVF. It’s also worth noting that PCOS patients who are taking gonadotropins have a very high risk of multiples.
The likelihood of a diagnosis of unexplained infertility is increased substantially in women 35 and over - and greatly increased in women over 38. The reason for this is that there are more likely to be egg quantity and quality problems as women age. Since we do not have a "standard category" called egg factor infertility, these couples sometimes get lumped in to the "unexplained" infertility category.
^ Chavez-Badiola, Alejandro; Flores-Saiffe Farias, Adolfo; Mendizabal-Ruiz, Gerardo; Garcia-Sanchez, Rodolfo; Drakeley, Andrew J.; Garcia-Sandoval, Juan Paulo (10 March 2020). "Predicting pregnancy test results after embryo transfer by image feature extraction and analysis using machine learning". Scientific Reports. 10 (1): 4394. Bibcode:2020NatSR..10.4394C. doi:10.1038/s41598-020-61357-9. PMC 7064494. PMID 32157183.

If you're not pregnant, you'll stop taking progesterone and likely get your period within a week. If you don't get your period or you have unusual bleeding, contact your doctor. If you're interested in attempting another cycle of in vitro fertilization (IVF), your doctor might suggest steps you can take to improve your chances of getting pregnant through IVF.


The live birth rate is the percentage of all IVF cycles that lead to a live birth. This rate does not include miscarriage or stillbirth; multiple-order births, such as twins and triplets, are counted as one pregnancy. A 2017 summary compiled by the Society for Assisted Reproductive Technology (SART) which reports the average IVF success rates in the United States per age group using non-donor eggs compiled the following data:[10]
In egg donation and embryo donation, the resultant embryo after fertilisation is inserted in another woman than the one providing the eggs. These are resources for women with no eggs due to surgery, chemotherapy, or genetic causes; or with poor egg quality, previously unsuccessful IVF cycles or advanced maternal age. In the egg donor process, eggs are retrieved from a donor's ovaries, fertilised in the laboratory with the sperm from the recipient's partner, and the resulting healthy embryos are returned to the recipient's uterus.
Secondary infertility (SI) is defined by doctors as the inability to conceive or carry to term a second or subsequent child. You may not have heard of it but you probably soon will, because it's on the increase. A US study revealed that, in 1995, 1.8 million women suffered from secondary infertility; in 2006, it was 3.3 million. SI now accounts for six out of 10 infertility cases.

Fertility has long been considered a “woman’s problem.” This is simply not true, and men are in fact, equally as infertile as women. Traditionally the metrics for male fertility have been mostly limited to sperm count, morphology, motility, and, occasionally, DNA fragmentation. For females, on the other hand, a vast array of tests are available. These include ultrasound, cervical position, basal body temperature, hysteroscopy, laparoscopy, cycle tracking and a diversity of hormonal tests.


Ovarian hyperstimulation is the stimulation to induce development of multiple follicles of the ovaries. It should start with response prediction by e.g. age, antral follicle count and level of anti-Müllerian hormone.[60] The resulting prediction of e.g. poor or hyper-response to ovarian hyperstimulation determines the protocol and dosage for ovarian hyperstimulation.[60]
The first step in finding the right treatment is to find out if there is an actual cause for unexplained infertility. Taking treatment helps to increase the chances of conceiving, and also makes it likelier that you will get pregnant sooner. The treatment of luteal-phase defects is as controversial as the diagnosis. They can be treated by using clomiphene, which may help by augmenting the secretion of FSH and thus improving the quality of the follicle (and therefore, the corpus luteum, which develops from it). Direct treatment with progesterone can also help luteal-phase abnormalities. Progesterone can be given either as injections or vaginal suppositories.

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]
^ Baker VL, Luke B, Brown MB, Alvero R, Frattarelli JL, Usadi R, et al. (September 2010). "Multivariate analysis of factors affecting probability of pregnancy and live birth with in vitro fertilization: an analysis of the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System". Fertility and Sterility. 94 (4): 1410–6. doi:10.1016/j.fertnstert.2009.07.986. PMID 19740463.
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