Higher Pre-Pregnancy BMI linked to Heart Defects
From Medscape:
NEW YORK (Reuters Health) Feb 01 - A higher pre-pregnancy body mass index (BMI) correlates with an increased risk of congenital heart defects, particularly conotruncal and right ventricular outflow tract (RVOT) defects, according to a recent study.
Common types of conotruncal defects include tetralogy of Fallot, truncus arteriosus, transposition of the great vessels, and double outlet of the right ventricle. RVOT defects include pulmonary atresia and pulmonary valve stenosis.
"Given the increased prevalence of pre-pregnancy obesity, the increased risk of alterations in glucose metabolism among women who are overweight or obese, and the association of maternal pregestational diabetes mellitus with congenital heart defects, it is valuable to clarify the association between pre-pregnancy BMI and congenital heart defects," lead author Dr. Suzanne M. Gilboa, of the Centers for Disease Control and Prevention, Atlanta, and colleagues write.
As reported in the American Journal of Obstetrics and Gynecology for January, the researchers used data from the National Birth Defects Prevention Study (1997-2004) to study links between pre-pregnancy weight and congenital heart defect phenotypes. The data came from 6440 infants with defects and 5673 control infants.
Mothers were categorized as underweight, normal weight, overweight, moderately obese, or severely obese according to standard BMI criteria.
Overweight, moderate obesity, and severe obesity increased the odds of a congenital heart defect by 16%, 15%, and 31%, respectively, relative to normal weight.
Overall, above-normal BMI (>25 kg/meters-squared) was associated with a number of phenotypes, including conotruncal defects in general (OR 1.16) and tetralogy of Fallot in particular (OR 1.24), total anomalous pulmonary venous return (OR 1.53), hypoplastic left heart syndrome (OR 1.32), RVOT defects in general (OR 1.34) and pulmonary atresia (OR 1.55) and valve stenosis (OR 1.36) in particular, septal defects in general (OR 1.15) and secundum atrial septal defects (OR 1.29) in particular.
"Given the increased prevalence of obesity and the public health importance of congenital heart defects, further work is warranted to determine the extent to which...type of obesity, patterns of dieting and weight change before and during pregnancy, physical inactivity, and inadequate levels of essential vitamins and nutrients, play a role in the associations with congenital heart defects," the researchers conclude.
Am J Obstet Gynecol 2010;51:e1-e10.
