Smoking, alcohol and caffeine in relation to ovarian age during the reproductive years

We sought to determine whether smoking, alcohol and caffeine are related to four indicators of ovarian age: antral follicle count (AFC), follicle stimulating hormone (FSH), inhibin B and estradiol.

Analyses drew on ultrasound scans and sera from 188 women, aged 22-49. We used least squares regression to estimate differences in AFC and hormone levels for women who smoke cigarettes or who drink alcohol or caffeine.

Current smoking is related to elevated FSH (beta for ln(FSH) = 0.21, 95% CI 0.04, 0.39), but not to AFC, inhibin B or estradiol. Neither alcohol nor caffeine is related to any ovarian age indicator. Exploratory analyses suggest that the association of current smoking with FSH varies with age: comparing current with never smokers, at ages 30, 35, 40 and 45, estimated differences in mean FSH are 0.3, 1.3, 3.2 and 6.9 mIU/ml.

The association of current smoking with FSH may reflect accelerated oocyte atresia, impaired follicle quality or dysregulation of the hypothalamic-pituitary-ovarian axis. Identification of the causal mechanism has implications for prevention or treatment of conception delay, infertility and morbidity associated with early menopause.