Coffee Drinking and the Risk for Miscarriage

Whether coffee drinking increases the risk for spontaneous abortion is a controversial question. In this nested case-control study, investigators measured paraxanthine, a metabolite of caffeine, in serum samples collected from women enrolled in the Collaborative Perinatal Project from 1959 to 1966.

Mean serum paraxanthine levels were significantly higher among 591 women who had spontaneous abortions before 140 days of gestation than among 2558 matched women from the same clinic who delivered live infants at 28 weeks of gestation or later (752 vs. 583 ng/mL). However, the adjusted odds ratio for spontaneous abortion was higher only for women who had serum paraxanthine levels above the 95th percentile of the matched women (equivalent to about …