The risk for congenital heart defects in offspring of individuals with congenital heart defects

Background: Congenital heart defects (CHDs) occur in approximately 1% of al l live births. Although most CHDs are of unknown etiology, a family history of CHDs is a known risk factor, and offspring of individuals with CHDs are at a higher risk of having CHDs. The aim of this study was to investigate the relative risk for CHDs to offspring of individuals with CHDs. Methods: The prevalence rates of CHDs in offspring of 203 individuals with CHDs and 282 individuals without CHDs were investigated. The study particip ants completed a questionnaire that included information on medical and rep roductive history, lifestyle indicators, and family history of CHDs and oth er congenital malformations. The prevalence rates of CHDs hi offspring were calculated. Results: The prevalence of CHDs was 3.1% (18/575) in offspring of individua ls with CHDs and 1.3% (8/589) in offspring of individuals without CHDs. The adjusted odds ratio for CHDs to offspring of parents with CHDs was 1.73 (9 5% confidence interval [95% CI] 0.89-2.44, p = 0.02). The estimated relativ e risk for offspring to females with CHD was higher than for males [2.3 (95 % CI 1.1-4.7, p = 0.03) versus 1.31 (95% CI 0.48-4.30, p = 0.66), respectiv ely]. There was no suggestion of association between CHDs and maternal smok ing, alcohol consumption, and use of medication during pregnancy. Conclusions: Offspring of parents with CHDs are at a higher risk for CHDs c ompared with the general population. Couples where one member is affected w ith CHD should receive pre-conceptional or pre-natal genetic counseling and should be informed about the magnitude of the potential risk of CHDs to th e offspring.