What maternal change occurs in the blood volume during pregnancy?

During pregnancy, significant physiological changes occur, particularly with respect to blood volume. The correct statement is that blood volume increases by 30-50%. This increase is vital for several reasons: it helps to provide adequate nutrition and oxygen to both the mother and the growing fetus, supports the increased metabolic demands of pregnancy, and prepares the body for blood loss during delivery.

The increase in blood volume is primarily composed of both plasma and red blood cells, but the rise in plasma volume is proportionally greater, leading to a dilutional effect on hemoglobin levels, which is why many pregnant individuals may experience a condition known as "physiologic anemia." This enhanced blood volume is crucial for ensuring adequate perfusion of the placenta and maintaining healthy blood pressure levels as the body adapts to the growing fetus.

Understanding this physiological adaptation is important for healthcare professionals monitoring pregnant individuals, as it influences assessments of maternal and fetal well-being throughout pregnancy.