A Longitudinal Study of Cardiovascular Dynamic Changes Throughout Pregnancy

Cardiac structure and function in normal pregnancy

“…The increase in HR starts in the first trimester, peaks at 15-25% higher in the third trimester and returns to preconception levels within the first 10 postpartum days [2,[4][5][6][7][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33].…”

Prospective observational study of serial cardiac output by transthoracic echocardiography in healthy pregnant women undergoing elective caesarean delivery

“…2,3 Some studies report a reduction in CO from the second trimester. 4 Serial data from the immediate peripartum period are often missing from longitudinal studies. 1,4 Postural changes are frequently employed during the establishment of neuraxial anaesthesia and for management of hypotension and maternal collapse, but few studies have examined the effect of posture on cardiac output in the peripartum period.…”

“…4 Serial data from the immediate peripartum period are often missing from longitudinal studies. 1,4 Postural changes are frequently employed during the establishment of neuraxial anaesthesia and for management of hypotension and maternal collapse, but few studies have examined the effect of posture on cardiac output in the peripartum period. It is expected that CO would increase in the head-down position and decrease in the head-up position based on physiological data in the healthy non-pregnant population.…”

Maternal haemodynamics in pregnancy

“…In the second and third trimester stroke volume has been found to remain stable at nonpregnant values; 29 to remain elevated throughout; 87 to increase progressively; 8889 and to decrease progressively, 85 even to levels below prepregnant values. 90 A recognized source of variability of cardiac output in the third trimester is the effect of the supine position. When cardiac output is measured with the pregnant woman lying flat on her back, the gravid uterus may impede venous return through the vena cava, thus decreasing preload with a consequent fall in cardiac output.…”