How Pregnancy Affects the Heart
Pregnancy places exceptional physiological demands on the cardiovascular system. Cardiac output increases by 30 to 50 percent, blood volume expands by approximately 40 to 50 percent, heart rate increases throughout gestation, and systemic vascular resistance drops — all changes that allow the placenta and fetus to receive adequate blood flow. For women with congenital heart disease, these hemodynamic changes can be destabilizing. A heart that functions adequately under resting conditions may decompensate when asked to maintain the elevated output demands of a term pregnancy. Arrhythmias may worsen. Ventricular function that appeared adequate on resting echo may prove insufficient under physiologic stress. Left-sided obstructive lesions, in particular, may precipitate pulmonary edema as cardiac output demands outpace what the obstruction allows.
Delivery Planning for Women With CHD
Delivery planning for women with congenital heart disease requires input from cardiology, maternal-fetal medicine, obstetric anesthesia, and labor and delivery nursing. Key decisions include the optimal gestational age for delivery, the appropriate delivery site (community hospital versus high-volume tertiary center), mode of delivery (vaginal versus cesarean), and the hemodynamic monitoring approach during labor. Most women with CHD can be considered for vaginal delivery with neuraxial anesthesia when their cardiology team has provided specific guidance to the obstetric team. Women with high-risk anatomies — particularly severe outflow tract obstruction, severe systolic dysfunction, or pulmonary hypertension — may be best delivered in tertiary centers with cardiac surgery and intensive care available on-site. Postpartum monitoring is equally essential, since the hemodynamic shifts of the early postpartum period can provoke decompensation in vulnerable patients.
Reviewed by Dr. Pradeepkumar Charla, MD, MBA, FAAP, FACC
Pediatric & Adult Congenital Cardiologist — Congenital Heart Compass Medical PLLC
Last reviewed:
Medical disclaimer: This content is for educational purposes only and is not a substitute for individualized medical advice, diagnosis, or treatment. Always consult a qualified cardiologist for decisions about your congenital heart disease care.