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.
In cases where the man's sperm count is extremely low or there is poor motility (movement of the sperm), doctors may combine IVF with a procedure called intracytoplasmic sperm injection. In this procedure, a sperm is taken from semen -- or in some cases right from the testicles -- and inserted directly into the egg. Once a viable embryo is produced, it is transferred to the uterus using the usual IVF procedure.
Preimplantation genetic screening (PGS) or preimplantation genetic diagnosis (PGD) has been suggested to be able to be used in IVF to select an embryo that appears to have the greatest chances for successful pregnancy. However, a systematic review and meta-analysis of existing randomised controlled trials came to the result that there is no evidence of a beneficial effect of PGS with cleavage-stage biopsy as measured by live birth rate. On the contrary, for women of advanced maternal age, PGS with cleavage-stage biopsy significantly lowers the live birth rate. Technical drawbacks, such as the invasiveness of the biopsy, and non-representative samples because of mosaicism are the major underlying factors for inefficacy of PGS.
Mutations to NR5A1 gene encoding Steroidogenic Factor-1 (SF-1) have been found in a small subset of men with non-obstructive male factor infertility where the cause is unknown. Results of one study investigating a cohort of 315 men revealed changes within the hinge region of SF-1 and no rare allelic variants in fertile control men. Affected individuals displayed more severe forms of infertility such as azoospermia and severe oligozoospermia.
While ICSI is a more invasive procedure, some have suggested it may help by reducing the risk of failed fertilisation. However, it's emerging that IVF is probably the preferred treatment, at least in the first cycle, in "unexplained" infertility. IVF allows for healthy competition between sperm, is less expensive, avoids trauma to the egg and may produce more embryos, with better pregnancy and live birth rates
With the exception of severe male infertility, 70% of the oocytes will become fertilized. In the case of severe male infertility, ICSI (pronounced ick-see) may be used to fertilize the eggs, instead of simply placing them in a culture dish. With ICSI, the embryologist will choose a healthy-looking sperm and inseminate the oocyte with the sperm using a special thin needle.
For women, problems with fertilisation arise mainly from either structural problems in the Fallopian tube or uterus or problems releasing eggs. Infertility may be caused by blockage of the Fallopian tube due to malformations, infections such as chlamydia or scar tissue. For example, endometriosis can cause infertility with the growth of endometrial tissue in the Fallopian tubes or around the ovaries. Endometriosis is usually more common in women in their mid-twenties and older, especially when postponed childbirth has taken place.
There’s an intense emotional response to hearing, “There is no apparent reason for your infertility”. It can be difficult, maddening and equally frustrating for both you and your partner. People who do find out a specific cause find their situations difficult, too, of course, but knowing the “whys” makes it more bearable. In cases of unexplained infertility, couples feel that one reason, one cause is lurking in a shadowy corner. It just hasn’t been uncovered yet.
These time intervals would seem to be reversed; this is an area where public policy trumps science. The idea is that for women beyond age 35, every month counts and if made to wait another six months to prove the necessity of medical intervention, the problem could become worse. The corollary to this is that, by definition, failure to conceive in women under 35 isn't regarded with the same urgency as it is in those over 35.