Purpose: In contrast to other hormonally mediated cancers such as those of the breast, prostate, and testes, almost no data are available regarding the relation of prenatal characteristics and exposures to subsequent ovarian carcinogenesis. In a population-based study of 812 women ages 35-74 years with epithelial ovarian cancer diagnosed in Washington State from 2002 to 2005 and 1313 controls, we assessed the relation of such factors to disease risk.
Methods: Information was collected through in-person interviews and logistic regression was used to calculate odds ratios and 95% confidence intervals.
Results: Overall, we noted little evidence that prenatal or birth characteristics including birth weight, birth order, maternal age, or in utero exposure to cigarette smoking were associated with risk of epithelial ovarian cancer in adulthood. Among women younger than 55 years of age, risk was reduced among those whose weight at birth was < 5.5 pounds (odds ratio and 95% confidence interval 0.54, 0.31-0.94) relative to those with birth weight 5.5-9 pounds.
Conclusions: In this study, birth weight was associated with risk of epithelial ovarian cancer only among women younger than 55 years of age. Prenatal influences might be expected to more substantially influence cancer risk at younger ages. Other reports examining associations of ovarian cancer risk with birth weight or other prenatal characteristics are few and have not examined risk separately according to age at diagnosis, suggesting that additional studies may prove useful.