Congenital Heart Defects: Understanding the Causes of Ventricular Septal Defect

Congenital heart defects (CHDs) are structural abnormalities of the heart that develop during fetal growth. While the exact causes remain unclear, medical experts have identified several potential contributing factors that may increase the risk of a baby being born with a heart defect such as ventricular septal defect (VSD).

Main Contributing Factors

1. Maternal Illnesses During Pregnancy

One of the most commonly discussed causes is illness in the mother during pregnancy, particularly viral infections like the common cold or rubella (German measles). Contracting such illnesses during the first trimester—when the baby's heart is forming—can interfere with normal development and increase the likelihood of congenital heart abnormalities.

2. Exposure to Certain Medications

Another possible cause is the use of specific medications during pregnancy, especially in the early stages when women may not yet be aware they are pregnant. Some drugs have been found to have teratogenic effects, meaning they can disrupt normal fetal development and potentially lead to heart defects like VSD.

3. Genetic and Hereditary Factors

There is also evidence to suggest that genetics play a role in the development of congenital heart defects. Some families have a history of heart conditions, indicating a possible hereditary component. If one child is born with a VSD, the chances of future siblings having a similar condition may be slightly elevated.

Uncertainty in Diagnosis and Causation

While the above factors are considered potential causes of congenital heart defects, it's important to note that their presence does not guarantee that a baby will be born with a heart condition. In many cases, even when these risk factors are present, babies are born completely healthy. Conversely, some infants develop VSD without any known cause or identifiable risk factor.

Medical research is ongoing, and scientists are working to better understand the complex interplay between environmental influences and genetic predisposition in the development of congenital heart defects. Early detection, improved surgical techniques, and better prenatal care continue to enhance outcomes for affected infants.