Birth defects are physical or functional abnormalities that occur during a baby’s development in the womb. They can affect how the body looks, works, or both. Some common types of birth defects include heart defects, cleft lip or palate, and spina bifida. The exact cause of many birth defects is often unknown, but they can result from genetic factors, environmental influences, or a combination of both. Preventive measures can help reduce the risk of birth defects. For example, women are encouraged to take prenatal vitamins containing folic acid before and during pregnancy, as this nutrient can help prevent certain defects. Additionally, avoiding harmful substances like alcohol and tobacco during pregnancy is crucial for the baby's health.