Ovulation induction and ovarian cancer: is there a link?

Introduction : Ovarian cancer accounts for approximately 4% of all cancers occurring in women and ranks the fourth most frequent cause of cancer-related death in women. Despite aggressive treatment modalities the 5 year survival rate remains less than 30%'. Almost 2.5% of all live births/ year result from assisted reproductive techniques (ARD2. Concern has been expressed that exposure to fertility drugs (FD) might be associated with a risk of ovarian tumors. Given the grave prognosis of ovarian cancer and the increasing use of ART, for the past several years this has been a subject of much scientific debate. The likely magnitude of risk may be 2 - 3 times that of the general population, which is at most 4-5% in a woman's lifetime. Several case control and cohort epidemiological studies have attempted to address this issue but failed to specifically look at drug treatment as risk factor and research to date demonstrates conflicting results.
Review of literature : Ovulation induction (Ol) agents are commonly used in the treatment of infertility in patients with or without ovulatory disturbances. These agents include clomiphene citrate (CC), bromocryptine, gonadotropins (Gn), Gonadotropin releasing hormone (GnRH) and its analogues. In in vitro fertilization (IVF), combinations and different drug dosages of FD are given to stimulate production of multiple oocytes. Fertility drugs were first marketed since the 1960's. The first to hit the market was CC in 1967 followed 2 years later by human Menopausal Gonadotropin (hMG) & human Chorionic Gonadotropin (hCG)'. Until 1987, most IVF cycles used CC in combination with HMG followed by hCG. From 1987, GnRH agonists were introduced to replace Cc. From 1990, the main drug regimen was GnRH agonist in combination with HMG or Follicular Stimulating Hormone (FSH) followed by hCG.