The prophylactic effect of doxycycline on postoperative infection rate after first-trimester abortion.

A prospective double-blind study was performed to evaluate the effect of prophylactic antibiotic treatment before induced abortion. Eight hundred consecutive women admitted for first-trimester abortion, without signs of genital infection or antibiotic use in the last three weeks, were included in the study. Doxycycline 400 mg or placebo was given as a single oral dose ten to 12 hours before vacuum aspiration. Ninety-one women (11.8%) returned to the hospital with suspected complications. Thirty-two of these women were diagnosed as having pelvic inflammatory disease, eight of whom (2.1%) had received doxycycline before the abortion and 24 of whom (6.2%) had received placebo, a statistically significant difference (P less than .01). A history of pelvic inflammatory disease increased the risk of developing it again after an abortion.