Infertility is “a disease of the reproductive system defined by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse (and there is no other reason, such as breastfeeding or postpartum amenorrhoea). Primary infertility is infertility in a couple who have never had a child. Secondary infertility is failure to conceive following a previous pregnancy. Infertility may be caused by infection in the man or woman, but often there is no obvious underlying cause.
The second study by Huang et al. demonstrated nearly equivalent pregnancy rates between the three medications. Furthermore, the twin risk was not significantly elevated in any of the three groups. The key difference between these studies is that the dose of gonadotropins was higher in the AMIGOS study (150 units) than the Huang study (75 units). A higher dose often means more eggs ovulated and a greater risk of twins or more.
A recent large population-based study collected data from almost 5000 European patients. According to preliminary results presented at the 2019 European Society of Human Reproduction and Embryology, there is no benefit from ICSI in non-male factor cases. Importantly, the study reported no benefit of using ICSI regardless of how many eggs are retrieved after ovarian stimulation. Therefore, having a low oocyte yield should not be a reason for choosing ICSI over IVF.

Women are not always the source of a couple's infertility—in approximately one-third of cases, men may have difficulty with conception. In another third of cases, men are a contributing factor, along with female infertility and other problems. Men should be evaluated by a physician if there is a family history of infertility, if they have undergone cancer treatment, if they have small testicles, a swollen scrotum, or a low sperm count, or if they have any other testicular, prostate, or sexual problems.

Fertilization. An embryologist (a scientist who specializes in eggs, sperm, and embryos) will examine your eggs before combining them with your partner's sperm and incubating them overnight. Fertilization usually happens during this time, but eggs that aren't normal may not be fertilized. (If sperm quality is poor, or if fertilization was unsuccessful during previous IVF cycles, your doctor may recommend using a technique called intracytoplasmic sperm injection (ICSI). With ICSI, a single sperm is injected directly into each mature egg.)
Cancer. Although some early studies suggested there may be a link between certain medications used to stimulate egg growth and the development of a specific type of ovarian tumor, more-recent studies do not support these findings. There does not appear to be a significantly increased risk of breast, endometrial, cervical or ovarian cancer after IVF.
Regardless of pregnancy result, IVF treatment is usually stressful for patients.[42] Neuroticism and the use of escapist coping strategies are associated with a higher degree of distress, while the presence of social support has a relieving effect.[42] A negative pregnancy test after IVF is associated with an increased risk for depression in women, but not with any increased risk of developing anxiety disorders.[43] Pregnancy test results do not seem to be a risk factor for depression or anxiety among men.[43]

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.
^ Sher, KS; Jayanthi, V; Probert, CS; Stewart, CR; Mayberry, JF (1994). "Infertility, obstetric and gynaecological problems in coeliac sprue". Dig Dis. 12 (3): 186–90. doi:10.1159/000171452. PMID 7988065. There is now substantial evidence that coeliac sprue is associated with infertility both in men and women. (...) In men it can cause hypogonadism, immature secondary sex characteristics and reduce semen quality. (...) Hyperprolactinaemia is seen in 25% of coeliac patients, which causes impotence and loss of libido. Gluten withdrawal and correction of deficient dietary elements can lead to a return of fertility both in men and women.
Ovulation induction with IUI: The goal with ovulation induction is to recruit and develop a single egg during the stimulation phase. At the time of ovulation, insemination occurs, placing the sperm directly into the uterus. IUI puts the sperm closer to the egg than possible with intercourse alone. You will come into the office for three to five monitoring appointments to track egg development and cycle timing.
The Rand Consulting Group has estimated there to be 400,000 frozen embryos in the United States in 2006.[83] The advantage is that patients who fail to conceive may become pregnant using such embryos without having to go through a full IVF cycle. Or, if pregnancy occurred, they could return later for another pregnancy. Spare oocytes or embryos resulting from fertility treatments may be used for oocyte donation or embryo donation to another woman or couple, and embryos may be created, frozen and stored specifically for transfer and donation by using donor eggs and sperm. Also, oocyte cryopreservation can be used for women who are likely to lose their ovarian reserve due to undergoing chemotherapy.[84]
Treatment depends on the cause of infertility, but may include counselling, fertility treatments, which include in vitro fertilization. According to ESHRE recommendations, couples with an estimated live birth rate of 40% or higher per year are encouraged to continue aiming for a spontaneous pregnancy.[63] Treatment methods for infertility may be grouped as medical or complementary and alternative treatments. Some methods may be used in concert with other methods. Drugs used for both women and men[64] include clomiphene citrate, human menopausal gonadotropin (hMG), follicle-stimulating hormone (FSH), human chorionic gonadotropin (hCG), gonadotropin-releasing hormone (GnRH) analogues, aromatase inhibitors, and metformin.
A genetic disorder. If you or your partner is at risk of passing on a genetic disorder to your child, you may be candidates for preimplantation genetic testing — a procedure that involves IVF. After the eggs are harvested and fertilized, they're screened for certain genetic problems, although not all genetic problems can be found. Embryos that don't contain identified problems can be transferred to the uterus.

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]