Final answer:
During pregnancy, there is a substantial increase in blood volume, rising by about 30 percent or 1-2 liters, resulting in moderately higher pulse and blood pressure and potentially causing varicose veins or hemorrhoids due to compression of pelvic blood vessels.
Step-by-step explanation:
Cardiovascular System Changes During Pregnancy
One of the significant changes to the cardiovascular system during pregnancy is an increase in blood volume.
The blood volume expands by approximately 30 percent by the time of childbirth, which reflects an increase of about 1-2 liters.
This adaptation helps accommodate the demands of both fetal nourishment and waste removal. Additionally, this increased volume contributes to a moderate rise in both pulse and blood pressure during pregnancy. As the uterus enlarges, it compresses veins in the pelvic area, inhibiting venous return from the lower extremities which can lead to the development of varicose veins or hemorrhoids.