Final answer:
Maternal blood volume increases by 30 percent during pregnancy to meet the demands of fetal nourishment and waste removal.
Step-by-step explanation:
During the course of pregnancy, the maternal blood volume increases to accommodate the needs of both the mother and the growing fetus. By the time of childbirth, the blood volume exceeds its preconception volume substantially.
Based on the information provided, the correct answer to the question is that maternal blood volume increases by 30 percent during pregnancy. This increase is essential for fetal nourishment as it helps in managing the demands associated with fetal nourishment and waste removal. Moreover, the cardiovascular changes including increased pulse and blood pressure, accommodate the growing fetus and the expanded circulatory needs.