Final answer:
During pregnancy, cardiac output increases due to a significant rise in maternal blood volume and other physiological changes, ensuring adequate blood flow to the mother and fetus. This increase is crucial for fetal development and the well-being of the mother, reflecting the body's adaptation to the demands of pregnancy.
Step-by-step explanation:
During pregnancy, cardiac output increases by up to 33% in women. This physiological adaptation occurs because there is a substantial increase in blood volume, to meet the heightened demands for fetal nourishment and waste removal. By the time of childbirth, maternal blood volume increases by 30 percent, or approximately 1-2 liters. Various factors contribute to this increase in cardiac output such as hormonal changes, increased metabolic rate, and the physical growth of the uterus which compresses the pelvic blood vessels, impeding venous return and necessitating a greater output from the heart.
This adjustment in cardiac output is essential as it ensures that both the mother's and the fetus’s tissues are adequately supplied with oxygenated blood. The heart rate and blood pressure also rise moderately to facilitate this enhanced blood flow throughout the mother’s body and to the placenta. Understanding this rise in cardiac output during pregnancy is crucial for monitoring the health of the mother and the developing fetus and for managing potential complications like varicose veins or hemorrhoids resulting from the increased pressure on the venous system.