Journal article

Publication year: 1999

Pages: 360-366

Journal: Der Gynäkologe

Volume number: 32

Issue number: 5

ISSN: 0017-5994

Publisher: Springer

Abstract: 
To test the hypothesis that cardiovascular adaptations to human pregnancy begin in the first 4 weeks post ovulation (PO) we obtained estimates of resting heart rate (HR), blood pressure (BP), stroke volume (SV), cardiac output (CO), peripheral resistance (TPR), and venous capacity (VC) and compliance (VCom) weekly under standard conditions beginning on day 3 of the menstrual cycle. The data obtained in cycles with conception were compared to those in which conception did not occur. Techniques utilized included EKG, automated blood pressure measurement (Dynamap), echocardiography, and plethysmography. No directional changes were observed in any parameter during the cycles in which conception did not occur. However, in cycles in which conception occurred HR increased 10 bpm within 1 week PO and remained at that level for the next 7 weeks. BP did not fall significantly until the 5th week PO, SV rose significantly between the 2nd and 3rd week PO and plateaued 10% above pre ovulatory levels thereafter. As a result, CO rose and TPR fell significantly within 1 week PO and plateaued 1.5 l/min above and 300 dyne/cm/s(-5) below pre ovulatory levels by the 3rd PO week. VC increased and followed a similar time course. These changes were associated with rapid increases in human chorionic gonadotropin, a fourfold increase in estradiol, and a twofold increase in progesterone. We conclude that the hypothesis is correct and speculate that the cardiovascular changes are initiated by the rapidly changing hormonal milieu.

Harvard Citation style: Kamali, P. and Clapp, J. (1999) Hormonal influences on cardiovascular function in early pregnancy, Der Gynäkologe, 32(5), pp. 360-366

APA Citation style: Kamali, P., & Clapp, J. (1999). Hormonal influences on cardiovascular function in early pregnancy. Der Gynäkologe. 32(5), 360-366.