How does blood volume change during pregnancy?

How does blood volume change during pregnancy?

• A. Increases 30 to 50%, peaking around 32-34 weeks
• B. Decreases slightly
• C. Remains the same
• D. Increases 70-90%

Answer: (A)

Blood volume expands significantly during pregnancy to support the fetus, placenta, and uterus and to prepare for blood loss at delivery. The total blood volume increases by about 40–50% above nonpregnant levels, with plasma volume rising more than red cell mass. This greater plasma expansion leads to a dilutional effect, so hematocrit and hemoglobin can appear lower even when iron status is adequate. The rise progresses through pregnancy and typically peaks in the late second to early third trimester, around 32–34 weeks.

Blood volume expands significantly during pregnancy to support the fetus, placenta, and uterus and to prepare for blood loss at delivery. The total blood volume increases by about 40–50% above nonpregnant levels, with plasma volume rising more than red cell mass. This greater plasma expansion leads to a dilutional effect, so hematocrit and hemoglobin can appear lower even when iron status is adequate. The rise progresses through pregnancy and typically peaks in the late second to early third trimester, around 32–34 weeks.