Do Fertility Drugs Cause Ovarian Tumors?

Objective: To evaluate the possible role fertility drugs may play in ovarian cancer etiology, summarize all cases reported to date, and describe ongoing research on this subject. Results: Five case control studies and two retrospective cohort studies examining the effect of ovulation induction on ovarian cancer risk were identified, along with one pooled reanalysis of three of these. These reports are discussed, with emphasis on the more recent findings. Reanalyzing the results of the pooled analysis using infertile women as the reference group revealed a statistically significant elevated risk of invasive epithelial ovarian cancer among fertility drug users (with an overall unadjusted odds ratio of 3.0 (95% confidence interval [CI] 1.3-7.2); for the subset of nulligravid women, it was 12 (95% CI 1.4-536)). Case reports of 58 ovarian tumors (42 of which were said to be malignant) in women exposed to fertility drugs are also described briefly. These were obtained from 15 unpublished reports received by the FDA and 15 publications in the medical literature. Conclusions: Due to the wide CIs around the estimates obtained to date and other considerations, the role of ovulation induction in the etiology of ovarian cancer remains an open question. New research efforts on this vital issue currently underway are described.