Circulatory Changes in Pregnancy

Plasma Concentrations of N-Terminal Pro-B-Type Natriuretic Peptide in Pregnant Women near Labor and during Early Puerperium

“…10,2005 women admitted in active labor, but in those women who did not have labor induced, postdelivery NTproBNP concentrations were higher. We cannot explain these results, as we would expect that women presenting in active labor would have higher NT-proBNP concentrations before labor than would those who were admitted for induction of labor because cardiac output increases moderately during the first stage of labor and even more during the second stage (18 ). Furthermore, we would not expect any difference in NT-proBNP concentrations after delivery because the hemodynamic changes are similar.…”

Management of Pregnancy in Patients With Complex Congenital Heart Disease: A Scientific Statement for Healthcare Professionals From the American Heart Association

“…[24][25][26][27][28][29][30][31][32][33] Maternal cardiac output increases 30% to 50% in a singleton pregnancy, with an additional 10% to 20% increment in a twin pregnancy. [34][35][36][37] Maternal posture can significantly affect cardiac output, especially after 20 weeks' gestation when the gravid uterus compresses the vena cava and pelvic veins.…”

“…Within 8 weeks after the last menstrual period, SVR has fallen by ≈30%, reaching a nadir at ≈24 weeks' gestation ( Figure 2). 23,25,27,43,[46][47][48][49][50] After 24 weeks' gestation, SVR begins to increase again, approaching preconception levels by term.…”

Pregnancy Issues in Women with Atrial Septal Defect

“…In second stage of labor, cardiac output increases significantly due to vigorous expulsive effort. (Ueland & Metcalfe 1975). …”