Objective: To study the human teratogenic risk of doxycycline treatment during pregnancy.
Methods: Paired analysis of cases with congenital abnormalities and matched healthy controls was performed in the large population-based data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1992.
Results: Of 32,804 pregnant women who had infants with no defects in the study period (control group), 63 (0.19%) were treated with doxycycline. Of 18,515 pregnant women who had offspring with congenital abnormalities, 56 (0.30%) were treated with doxycycline, a rate that is higher than that of the control group (P = .01). However, the case-control pair analysis did not show a significantly higher rate of doxycycline treatment in the second and third months of gestation in any group of congenital abnormalities.
Conclusions: Treatment with doxycycline during pregnancy presents very little if any teratogenic risk to the fetus. Thus, if doxycycline treatment is necessary during pregnancy, there would appear to be no contraindication.