DEAR MAYO CLINIC: I am ready to start a family, but my doctor said that pregnancy may be high-risk for me because I have a heart condition. Can you explain how pregnancy affects the heart and what I can do to lower my risk for complications?
ANSWER: Pregnancy results in many changes that can increase the workload of the heart. During pregnancy, your blood volume increases by 30% to 50% to nourish your growing baby, your heart pumps more blood each minute and your heart rate increases. Rapid changes occur during labor and delivery that affect the heart, as well, and further increase the workload. After delivery, it will take several weeks for your body to return to the prepregnancy state.
The increased workload during pregnancy and delivery can cause some complications. However, many women who have heart conditions deliver healthy babies. If you have a heart condition, you'll need special care during pregnancy to reduce the risk of complications to you and your baby.
Maternal cardiac disease complications occur in about 1% to 3% of all pregnancies. The risks depend on the nature and severity of your heart condition.
Consider these heart conditions:
Before you try to conceive, you may want to schedule an appointment with a maternal cardiologist who is experienced in managing heart disease during pregnancy. This would be a specialist who would work in conjunction with the health care provider who will handle your pregnancy.
A maternal cardiologist will evaluate your current heart condition, discuss the risk of pregnancy specific to you and your condition, and make recommendations for treatment changes prior to pregnancy.
Certain heart conditions should be treated before pregnancy to make the pregnancy lower-risk. This can include heart surgery, for example, to treat a heart valve condition such as aortic stenosis. Pregnancy is high risk for women with high lung artery pressures, or pulmonary hypertension, or severely reduced heart function. In these cases, avoid pregnancy.
Also, the specialist can review any medication adjustments, as certain medication you take during pregnancy can affect your baby. Certain medications used to treat heart conditions aren't used during pregnancy. Depending on the circumstances, your health care provider might adjust the dose or make a substitution and explain the risks involved. Often the benefits outweigh the risks, however. If you need medication to control your heart condition, your health care provider can prescribe the safest medication at the most appropriate dose. It is important that throughout your pregnancy you take the medication exactly as prescribed. Don't stop taking the medication or adjust the dose on your own.
During pregnancy, you may be referred to an obstetrician who specializes in high-risk pregnancies. This provider is known as a maternal fetal medicine specialist. Depending on the circumstances, you also may be referred to a medical geneticist, a neonatologist and an obstetric anesthesiologist to help manage your pregnancy and delivery. Most women with heart conditions can and should deliver their baby vaginally. Cesarean delivery is reserved for obstetrical reasons and rare cardiac complications. — Dr. Sabrina Phillips, Division of Cardiovascular Medicine, Mayo Clinic, Jacksonville, Florida