Cephalothin prophylaxis for midtrimester abortion.

A randomized prospective double-blind study was conducted to determine the efficacy of prophylactic antibiotics as compared with placebo in 198 women undergoing second-trimester intraamniotic injection abortions. Patients received either sodium cephalothin or placebo intravenously before the procedure and for up to 8 additional doses. In 11 patients postabortion endometritis developed; 2 had received the antibiotic and 9 had received a placebo (P less than .05). Prophylactic cephalothin decreased the incidence of endometritis in patients undergoing midtrimester injection abortion. An injection-abortion interval greater than 24 hours appears to identify patients at risk for the development of postabortion endometritis.