MONTEREY, CALIF. — Women with thyroid disease are 50% more likely to have a child with left ventricular outflow tract obstruction than women without thyroid disease, according to a study that compared about 6,000 women in each of the two groups.
In particular, the risk of aortic valve stenosis and/or coarctation of the aorta appeared to be elevated, Marilyn L. Browne of the New York State Department of Health and her colleagues wrote in a poster presentation at the annual meeting of the Teratology Society.
There were no other statistically significant associations between maternal thyroid disease and congenital cardiovascular malformations.
The multicenter case control study was part of the National Birth Defects Prevention Study (NBDPS), which collects data from 10 regions in the United States. The investigators identified 6,068 women with a thyroid disease whose babies were born between October 1997 and December 2004 and compared them with 5,875 controls.
There were no significant demographic differences between the case and control groups, they reported.
The odds ratios were adjusted for potential confounders, including maternal age, race/ethnicity, education, prepregnancy BMI, gestational diabetes, smoking, alcohol use, and the state of residence at time of delivery.
The investigators acknowledged that their study did not identify the women's underlying thyroid conditions. They recommended that additional studies should evaluate the risks of antithyroid medication and should examine risk by type of thyroid disorder.
Ms. Browne stated she had no conflicts of interest to disclose related to her presentation.