BODY-MASS INDEX AND OVULATORY INFERTILITY

Several studies have examined the association between body mass index and infertility. We compared body mass index in 597 women diagnosed wi th ovulatory infertility at seven infertility clinics in the United St ates and Canada-with 1,695 primiparous controls who recently gave birt h. The obese women (body mass index greater than or equal to 27) had a relative risk of ovulatory infertility of 3.1 [95% confidence interva l (CI) = 2.2-4.4], compared with women of lower body weight (body mass index 20-24.9). We found a small effect in: women with a body mass in dex of 25-26.9 or less than 17 [relative risk (RR) = 1.2, 95% CI = 0.8 -1.9; and RR = 1.6, 95% CI = 0.7-3.9, respectively). We conclude that the risk of ovulatory infertility is highest in obese women but is als o slightly increased in moderately overweight and underweight women