The greatest risk for prenatal defects exists when a mother contracts rubella
A)in the third month of pregnancy.
B)in the second trimester of pregnancy.
C)right before birth.
D)in the third or fourth week of pregnancy.

Question

Quizplus · Accepted Answer

The greatest risk for prenatal defects from rubella exists when a mother contracts it in the first four weeks of pregnancy. This is because this is when the fetus's major organs are developing. Rubella is less likely to cause defects when contracted in the second trimester, and the risk is very low if contracted right before birth.

The Greatest Risk for Prenatal Defects Exists When a Mother