Adapted from the American Journal of Obstetrics and Gynecology 1996

The change from the recumbent position to standing produces acute hemodynamic changes that are exaggerated during pregnancy. The result is that in the third trimester, standing can produce a decrease in blood pressure and cardiac output, followed by increases in maternal heart rate and systemic vascular resistance. To compensate for the positional change, chemical compounds derived from the amino acid tyrosine, catecholamines, are released to increase vascular resistance and normalize blood pressure and heart rate. Graduated compression stockings have been shown to reverse these effects.

The authors conclude that the use of support stockings during pregnancy is associated with favorable cardiovascular effects. They point out that support stockings may be useful clinically to reduce contractions that occur in pregnant women on standing. Thus, use of compression stockings during pregnancy appears to promote beneficial hormonal, mechanical and cardiovascular effects.