Which of the following is a cause of intellectual disability during pregnancy?

• A. Development inside womb
• B. Fetal alcohol spectrum disorders
• C. Rubella infection during pregnancy
• D. Lack of oxygen during birth

Answer: (C)

Intellectual disability can result from insults to the developing brain while the baby is still in the womb. One well-known prenatal cause is maternal rubella infection, which can cross the placenta and lead to congenital rubella syndrome. This syndrome often includes intellectual disability along with other problems like heart defects or eye abnormalities. The damage is most likely when infection happens early in pregnancy, during the period of rapid brain development, so preventing rubella through vaccination before pregnancy dramatically reduces this risk. While fetal alcohol exposure and other prenatal factors can also cause intellectual disability, rubella is the classic infectious prenatal cause highlighted in many clinical scenarios.