What is a Congenital Heart Defect?
Congenital heart defect (CHD) or congenital heart anomaly is a defect in the structure of the heart and great vessels which is present at birth. Many types of heart defects exist, most of which either obstruct blood flow in the heart or vessels near it, or cause blood to flow through the heart in an abnormal pattern. Other defects, affect the heart’s rhythm.
Heart defects are among the most common birth defects and are the leading cause of birth defect-related deaths. Approximately 9 people in 1000 are born with a congenital heart defect. Many defects don’t need treatment, but some complex congenital heart defects require medication or surgery.
A study completed by Hobbs et al (2010) examined the prevalence of MTHFR mutations in women with CHD affected pregnancies. Results showed that women carrying a CHD pregnancy were 1.5 times more likely to be obese when compared to women in the control group. Obese women in the study group (not control) carrying the 677TT mutation were also found to be 4.6 times more likely to have a CHD affected pregnancy when compared to women with the C677C genotype of a normal weight. Furthermore, the presence of the A allele in the BHMT gene also lead to 1.8 increased risk of a C pregnancy, when compared with women of a normal weight with the GG genotype.