Contact Answers In the News Hot Topics

Pregnancy Bliss | Reproductive Health Answers

© 2007-2012. All rights reserved
Share on Facebook
Share on Twitter
Share on Digg
Share on Google Bookmarks
Share on Reddit
Share via e-mail

Published: Monday, March 21, 2011 - 22:09

Congenital Heart Defects (CHDs) are the most common birth defects among newborns, with 80 cases per 10,000 live births. They are a leading cause of infant mortality. Now, results from a large study has linked first trimester maternal smoking with some Congenital Heart Defects (CHDs). Results of this study appear in the March 2011 issue of the journal Pediatrics.

In the Baltimore-Washington Infant Study, which was the first US population-based case-control study of CHDs, case and control newborns were enrolled from 1981 to 1989. Diabetes on the parts of mothers and infants with Down’s syndrome are conditions which are known to be associated with a higher risk of CHDs. Because of that mothers with overt pre-pregnancy diabetes were excluded from the analysis, as were case mothers whose infants had non-cardiac anomalies, except for atrioventricular (AV) septal defects accompanying Down's syndrome. Therefore, the analysis included a total of 2525 case and 3435 control infants.

In-person interview after delivery allowed determination of self-reported first-trimester maternal cigarette smoking and the rate thereof. Logistic regression models were used to evaluate associations for 26 different groups of congenital heart defects (CHDs) with maternal cigarette smoking. Odds ratios (ORs) were estimated for an increase in 20 cigarettes per day.

Various types of defects caused

The types of CHDs associated with maternal smoking are truncus arteriosus, levo-transposition of the great arteries, right ventricular outflow tract obstruction defects, pulmonary valve stenosis, and secundum type atrial septal defect.

"Results of this study, based on a population-based design with high-quality case ascertainment and defect classification, add to the existing body of evidence that implicates first-trimester maternal cigarette smoking as a modest risk factor for select congenital heart defect phenotypes," the study authors conclude.

Source abstract:

Maternal smoking associated with congenital heart defects

By Dr Joe Kabyemela, MD