News: Multivitamins reduce risk of ovulatory infertility

Regular use (6 times per week) of multivitamin supplements containing folic acid cuts the risk of ovulatory infertility by almost half, according to the results of a prospective cohort study.

The study included over 18,000 married, premenopausal participants in the Nurses' Health Study II. The women had no history of infertility and attempted pregnancy or became pregnant between 1991 and 1999.

During 8 years of follow-up, 438 women experienced infertility with an ovulatory cause. The researchers found an inverse association between frequency of multivitamin use and ovulatory infertility. Compared with women consuming no supplements (P, trend <.001), the multivariate-adjusted relative risk (RR) of ovulatory infertility was 0.88 (95% CI, 0.60–1.28) for women consuming two or fewer tablets per week, 0.69 (0.51–0.95) for women consuming three to five tablets per week, and 0.59 (0.46–0.75) for women consuming six or more tablets per week.

Chavarro JE, Rich-Edwards JW, Rosner BA, et al. Use of multivitamins, intake of B vitamins, and risk of ovulatory infertility. Fertil Steril. 2008;89:668-676.