Paroxysmal supraventricular tachycardia in pregnant women and birth outcomes of their children: a population-based study.

The aim of the study was to estimate the possible association of pregnant women with paroxysmal supraventricular tachycardia (PSVT) with the possible risk for adverse birth outcomes, particularly different congenital abnormalities (CAs) in their children. Prospectively and medically recorded PSVT was evaluated in 103 pregnant women who later had offspring with CA (case group) and 149 pregnant women who later delivered newborn infants without CA (control group) and matched to cases in the population-based data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities, 1980-1996. Of 252 pregnant women with PSVT, 115 (45.6%) had the onset of this condition before the study pregnancy, that is, their PSVT was a chronic condition, while the rest (N = 137) of PSVT was considered as new onset in the study pregnancy. The comparison of occurrence of PSVT in pregnant women who had offspring with different CA groups and in control mothers showed a higher risk for cardiovascular CAs (adjusted OR with 95% CI: 2.1, 1.1-3.8) explained mainly by secundum atrial septal defect. This association was confirmed in pregnant women with PSVT in the second and/or third gestational month, that is, critical period of cardiovascular CAs. In conclusion PSVT in pregnant women associates with a higher risk of secundum atrial septal defect in their children.