Population-based case-control study of oxoline acid use during pregnancy for birth outcomes.

The objective of the study was to check the effect of oxoline acid, a bactericidal drug for the treatment of urinary tract infection during pregnancy, on congenital abnormalities of informative offspring and fetal development. Human data of oxoline acid use during pregnancy have not been reported, but the use of this quinolone derivative is not recommended during pregnancy by the US Food and Drug Administration. The teratogenic and fetotoxic potential of oxoline acid was evaluated in the population-based large data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities between 1980 and 1996. Observed and expected numbers of congenital abnormalities were compared in the newborn infants and fetus of case mothers with oxoline acid treatment. In addition, gestational age and birthweight were evaluated in control newborn infants born to mothers with or without oxoline acid treatment. Of 38,151 newborn infants without any congenital abnormalities (control group), 13 (0.03%) had mothers who were treated with oxoline acid, while of 22,843 cases with congenital abnormalities, five (0.02%) had mothers who were treated with oxoline acid during pregnancy (POR with 95% CI: 0.6, 0.2-1.8). The comparison of observed and expected number of different congenital abnormalities did not show the teratogenic potential of oxoline acid. There was a 0.9 weak shorter gestational age without a smaller birthweight in the newborn infants born to mothers with oxoline acid treatment. Our data did not indicate teratogenic and fetotoxic effect of oxoline acid, however, the number of cases and controls was limited.