Failure to Ovulate
Ovulatory disorders are one of the most common reasons why women are unable to conceive, and account for 30% of women's infertility. Fortunately, approximately 70% of these cases can be successfully treated by the use of drugs such as Clomiphene and Menogan/Repronex. The causes of failed ovulation can be categorized as follows:
Hormonal problems are the most common causes of failure to ovulate (anovulation). The process of ovulation depends upon a complex balance of hormones and their interactions to be successful, and any disruption in this process can hinder ovulation. See more on hormonal causes of infertility.
Physical damage to the ovaries may result in failed ovulation. For example, extensive, invasive, or multiple surgeries, for repeated ovarian cysts may cause the capsule of the ovary to become damaged or scarred, such that follicles cannot mature properly and ovulation does not occur. Infection may also have this impact.
This presents a rare, and as of yet, unexplainable cause of anovulation. Some women cease menstruation and begin menopause before normal age. It is hypothesized that their natural supply of eggs has been depleted or that the majority of cases occur in extremely athletic women with a long history of low body weight and extensive exercise. There is also a genetic possibility for this condition.
Although currently unexplained, "unruptured follicle syndrome" occurs in women who produce a normal follicle, with an egg inside of it, every month yet the follicle fails to rupture. The egg, therefore, remains inside the ovary and proper ovulation does not occur.
Much of this information is from the