Ovulation induction for polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is the commonest cause of anovulatory infertility. Various factors influence ovarian function, and fertility is adversely affected by an individual being overweight or having high serum concentrations of LH. Strategies to induce ovulation include weight loss, oral anti-oestrogens (principally clomiphene citrate), parenteral gonadotrophin therapy and laparoscopic ovarian surgery. There have been no adequately powered randomized studies to determine which of these therapies provides the best overall chance of an ongoing pregnancy. Women with PCOS are at risk of ovarian hyperstimulation syndrome (OHSS) and so ovulation induction has to be monitored carefully with serial ultrasound scans. The recognition of an association between hyperinsulinaemia and PCOS has resulted in the use of insulin sensitizing agents, such as metformin, which appear to ameliorate the biochemical profile and improve reproductive function.