Safety of the new quinolones in pregnancy

To investigate the effect on the fetus of intrauterine exposure to quinolones in terms of teratogenicity, with special focus on the musculoskeletal system.

We studied 38 pregnant women who received quinolones and consulted the Motherisk Program in Toronto from 1989-1992. Perinatal complications, birth weight, birth defects, and developmental milestones, with particular emphasis on the musculoskeletal system, were compared with those of controls matched for both maternal age and indication for antibacterial therapy.

Thirty-five women (92%) treated with norfloxacin or ciprofloxacin received therapy during the first trimester. The most common indication for therapy (92%) was urinary tract infection. More pregnancies in the quinolone group resulted in cesarean delivery due to reported fetal distress as compared to the controls (P = .005), without clear reason. Children born to mothers treated with quinolones were significantly heavier (P = .05) than the control infants, possibly because of better control of the urinary tract infection. No malformations were found in the quinolone group, whereas one child in the control group had a ventricular septal defect. No differences were detected between the groups in achievement of developmental milestones or in the musculoskeletal system.

The use of the new quinolones during the first trimester of pregnancy does not appear to be associated with an increased risk of malformations or musculoskeletal problems; however, longer follow-up and magnetic resonance imaging of the joints may be warranted to exclude subtle cartilage and bone damage.