Causes Of Congenital Heart Disease

Congenital heart disease (CHD) can arise from a variety of factors, often involving genetic, environmental, and lifestyle influences. Below are the primary causes associated with the development of congenital heart defects:

1. Family History Of Congenital Heart Disease

If one or both parents have congenital heart disease, the risk of their child developing a similar condition increases significantly—approximately 10% in such cases. This suggests a strong genetic component in the development of certain heart defects.

2. Maternal Diabetes

Women who have uncontrolled diabetes during pregnancy are at a higher risk of having a baby with CHD. Studies show that poorly managed diabetes can increase the risk by up to 2%. However, if blood sugar levels are well-controlled early in pregnancy, this risk can be significantly reduced.

3. Exposure To Teratogenic Medications

During the first trimester, exposure to certain medications—such as lithium, phenytoin, or corticosteroids—can raise the likelihood of congenital heart defects by about 2%. These drugs are considered teratogens and should be carefully managed during early pregnancy.

4. Radiation Exposure

Excessive exposure to radiation, such as X-rays or radioactive isotopes, during the early stages of pregnancy can interfere with fetal development and increase the chances of heart malformations. Expectant mothers should avoid unnecessary radiation exposure, especially in the first few weeks of gestation.

5. Viral Infections During Pregnancy

Infections contracted during the first trimester—particularly between weeks 3 and 8—can greatly increase the risk of cardiovascular abnormalities in the fetus. The rubella virus is the most commonly identified cause of congenital heart defects. Other viruses, including influenza, mumps, coxsackievirus, and herpes, have also been linked to heart malformations in newborns.

6. Consanguineous Marriage

Children born from parents who are closely related have a higher risk of congenital heart disease due to the increased likelihood of inheriting recessive genetic mutations. This factor is considered a significant contributor to congenital anomalies, including heart defects.

7. Harmful Lifestyle Habits

Unhealthy behaviors such as smoking or alcohol consumption can negatively impact fetal heart development. Both maternal and paternal smoking increases the risk of congenital defects due to harmful chemical exposure. Additionally, passive smoking during pregnancy can lead to similar risks. Alcohol consumption around the time of conception may cause chromosomal abnormalities, potentially resulting in fetal alcohol syndrome, which is often associated with structural heart defects.