Heart Disease in Pregnancy


Your heart works harder during pregnancy to keep up with the demands of your growing baby. That’s why pregnancy is sometimes described as a “stress test” for your heart. It can uncover a heart problem you weren’t aware of, or make a known heart condition worse.

Some heart problems run in families, so your baby could also be affected.


dr colin walsh heart disease in pregnancy

Types of heart disease I see in pregnant women

  • Congenital cardiac problems (you were born with the condition). Usually women know they have a heart problem, or they had a surgical repair in childhood. Examples include ‘holes in the heart’ (atrial and ventricular septal defects), co-arctation of the aorta, Tetralogy of Fallot.
  • Ischaemic heart disease (angina, ‘heart attacks’). We are seeing more of this as mothers are getting older.
  • Valve problems. Valves in the heart keep the blood flowing in the right direction. Valves can become too narrow (stenosis) or stop closing all the way (regurgitation).
  • Cardiomyopathy – basically the heart muscle doesn’t pump properly. It can be due to genetic abnormalities, viruses, drugs, high blood pressure, other diseases like diabetes, and even pregnancy itself.
  • Arrhythmias – when the heart beats too fast, too slow, or is irregular. This includes women with pacemakers and automatic defibrillators.

How will a heart problem affect my pregnancy?

This is a huge topic – there are whole textbooks devoted to heart disease in pregnancy! But as a first step, these are some of the questions you and your doctors need to consider:

    • What is the condition?
    • How badly does it limit your physical activity?
    • What medications do you take? Are they safe for an unborn baby?
    • Is your baby also likely to have this heart problem?
    • Which doctors need to be on your team? It might include a cardiologist, cardio-thoracic surgeon, Maternal-Fetal Medicine specialist, obstetric physician, anaesthetist, geneticist…
    • Do you need special tests before or during pregnancy?
    • Is the extra strain of pregnancy likely to cause you harm?
    • Is pregnancy safe at all? There are a handful of conditions where pregnancy is simply considered too dangerous.
    • What is the safest way to give birth – vaginal birth or caesarean?
    • Is your local hospital ok for the birth, or do you need to be referred to a major hospital?

Pre-pregnancy counselling

If you have a heart problem and are considering pregnancy, then pre-pregnancy counselling is absolutely essential. You need to clearly understand your level of risk. You may also need special tests or a change in your medications before you conceive. It gives you time to assemble the right team of doctors and work out a roadmap for ongoing care.