Pregnancy and heart health: What you need to know

A healthy living blog from Marshfield Clinic Health System

Jun 23, 2023

Woman making a heart with her hands over her pregnant belly - Heart health and pregnancy — Cardiac output increases by 50 percent during pregnancy and even more so during delivery.

Most healthy women can safely endure pregnancy and the increased strain it puts on the heart.

The same goes for most women with heart conditions.

“It is very rare that a heart condition is so severe that a woman should not become pregnant,” said Dr. Maria Mascola, Marshfield Clinic maternal and fetal medicine specialist.

Heart health during normal pregnancy

Cardiac output increases by 50 percent during pregnancy and even more so during delivery. The increased blood flow is needed for a baby’s growth, the uterus and placenta.

Healthy women can usually tolerate this increased demand without a problem, Mascola said.

To maintain optimal heart health during a normal pregnancy, women should:

Eat a healthy, well-balanced diet.
Exercise 30 minutes most days (before, during and after pregnancy).
Avoid all tobacco use.

Pregnancy with a heart condition

The story changes slightly for pregnant women who have heart defects or other heart conditions.

“Most women with heart conditions handle pregnancy just fine and their babies arrive healthy,” Mascola said. “But they and their medical team need to take extra precautions and schedule more appointments for close monitoring.”

Women with heart conditions can expect:

Increased doctor-to-patient communication. The medical team asks for extra tests, schedules additional visits and performs more ultrasounds and echocardiograms.
A larger medical team. Expecting mothers with heart defects may have a team including an OB/GYN or maternal and fetal medicine specialist, a cardiologist and an internal medicine specialist.
Medication changes. Some heart medications, like beta blockers and calcium channel blockers, are safe to take during pregnancy. Others, like ACE inhibitors, ARBs and warfarin, must be changed before pregnancy.

Risks of a heart condition pregnancy

It is not safe for women with some heart conditions, like severe pulmonary hypertension or valvular stenosis, to be pregnant. There could be higher rates of early delivery, the baby not growing well or fatality.

“Parents-to-be should also know their family history,” she said. “If mom, dad or another close relative was born with a heart condition, chances increase that the baby will also be born with a heart condition.”

Preconception consults and vitamins

“Heart defect or not, we prefer all women talk to their health care providers when planning pregnancy and if there are medical conditions to visit us for a preconception consult,” Mascola said.

In preconception consults, doctors check that health conditions are under control, vaccinations are current and lifestyle factors and medication changes are discussed.

“We do understand life happens and sometimes pregnancies are unplanned,” she said. “In all cases, it’s very important that women of reproductive age who are sexually active take daily multivitamins.”

Multivitamins contain folic acid, which is associated with lower rates of birth defects including a lower rate of congenital heart defects.