Experimental studies on reproduction with the lipid-regulating agent gemfibrozil.

Gemfibrozil, a new lipid-regulating agent, was evaluated in rats and rabbits for effects on various phases of the reproduction process. In teratology studies groups of pregnant rats and rabbits received gemfibrozil at doses up to 200 mg/kg during organogenesis (rat, Days 6-15; rabbit, days 6-18). For peri- and postnatal studies, groups of pregnant rats were given 92 or 331 mg/kg from Day 15 of gestation through weaning. In fertility studies groups of sexually mature male rats were given 93 or 326 mg/kg of gemfibrozil for 61 days and females were given 94 or 318 mg/kg for 15 days prior to mating within treatment groups. Drug administration continued in females through gestation and weaning of the F1 offspring. In subsequent fertility experiments, treated male rats were mated with untreated females and treated females were cohabitated with untreated males. Gemfibrozil did not elicit a teratogenic response in either rats or rabbits up to doses that resulted in maternal toxicity. Reduced pup weights during the neonatal and weaning periods in the female fertility study as well as in the perinatal-postnatal study were the only apparent drug effect. Treatment of female rats prior to mating had no significant effects on general reproductive parameters. Male rats given doses of about 300 mg/kg/day showed inconsistent and equivocal lower rates of fertility relative to the concurrent controls. No adverse effects were seen in the reproductive performance of offspring of gemfibrozil-treated male rats.