Does Blood Volume Change During Pregnancy?

Yes — blood volume increases 50 percent during pregnancy. This is partially due to an increase in the fluid levels in the blood. Though red blood cell count increases, anemia can still be an issue, even with the increase in blood volume. White blood cell count also increases, especially during labor and the following few days.

More Pregnancy Facts:

• Near the end of a pregnancy, a woman's uterus takes up about 1/5 of the body's blood supply. This requires the heart to pump more blood and work harder.


• A woman's resting heart rate can increase during pregnancy as well. A normal resting heart rate is about 70 beats per minute — a pregnant woman's resting heart rate can be 80 or 90 beats per minute. Her heart rate returns to normal about six weeks after giving birth.


• About four out of five women experience morning sickness during pregnancy. Some studies have shown, however, that the hormones and chemicals released due to morning sickness may increase the intelligence of the baby. Morning sickness, which can actually happen at any time of the day, is also linked to a decreased chance of miscarriage.