discoveries magazine

Research Frontier: Pregnancy and Heart Health

Pregnant woman having her blood pressure taken.

While pregnancy lasts only about 40 weeks, it can create changes that last a lifetime. When mothers embrace their newborn family member, they’re also facing the ways that pregnancy affects the body—many of which are still unknown.

“Unknown is a nice way of putting it,” says Natalie Ann Bello, MD, MPH, director of hypertension research at the Smidt Heart Institute. “I would say understudied, under-resourced and possibly ignored.”

Dr. Bello is on a mission to change that. Her research into the ties between heart health and pregnancy place her at the intersection of cardiology, obstetrics and primary care. She co-chairs a work group for the American College of Cardiology that focuses on cardio-obstetrics, aiming to expand scientific knowledge, inform cardiologists and obstetricians of the heart health needs of pregnant patients and advocate for policy changes to help this population.

Here, Dr. Bello shares some insights into heart health and pregnancy.

The United States has among the highest rates of maternal morbidity and mortality compared to similarly wealthy countries. What role does heart health play?

Dr. Natalie Ann Bello: Cardiovascular disease is now the leading cause of death for women in pregnancy. Historically, infection and bleeding were the most common. Thankfully, we’ve been able to make improvements in the early diagnosis and treatment of those preventable conditions. Now, for a combination of reasons, cardiovascular disease is a rising concern.

More people have high blood pressure, more have diabetes and more are delaying pregnancies. So, as we shift that time frame, risk factors for cardiovascular disease accumulate. Pregnancy is a stress test for the body, and it can tip some people over into having a heart-health issue that needs to be addressed.

Can pregnancy complications affect long-term health?

NAB: Two of the most common pregnancy conditions are preeclampsia—a serious blood pressure condition that develops during pregnancy or just after delivery and is associated with protein in the urine and signs of organ damage—and gestational hypertension, which is elevated blood pressure during pregnancy. These and other complications can impact people’s risk of heart disease in the short term and long term. We know those individuals are at a higher risk for heart failure, and for stroke. I’m collaborating with colleagues in neurology, and we’re also starting to see signals toward increased risk for cognitive changes and dementia. 

It’s important that individuals know about any complications they had during pregnancy and speak to their primary care doctors or OB-GYNs. They need to have conversations about cholesterol checks, blood pressure checks and other health maintenance that will help them stay on top of their heart health.

Women with children are very, very busy and tend to put everyone else before themselves. We really need to take ownership of our health and be advocates for ourselves. That might mean deciding you need more frequent blood pressure and cholesterol checks.

Why is there a lack of data about blood pressure and pregnancy, and pregnancy in general?

NAB: Our goal in medicine, in addition to healing and promoting health, is to never cause any harm. After the thalidomide catastrophe—when a common drug given during pregnancy for nausea resulted in severe birth defects—the medical community pulled back strongly. This meant, unfortunately, anyone who was pregnant or could even become pregnant was excluded from medical research—even when it could potentially help these patients.

Though we’re still lagging behind, these populations are now mandated to be safely included in medical research by the National Institutes of Health.

There are so many people who have been ignored by medical research for a long time, and medicine is an evidence-based field. We can be more confident in our recommendations when we know that the research represents everyone.

What are some of the important research questions that need to be examined relating to pregnancy and heart health?

NAB: We need to better understand patients who are at risk for high blood pressure when they’re pregnant. One of the areas I’m investigating is the use of home blood pressure monitoring during pregnancy for women with chronic and gestational hypertension.

In the big picture, we need to get our pregnancy data in line with what we know about other adults. How do we best measure blood pressure at home during pregnancy? How many days do we do it? How do we define the cutoffs for high blood pressure in pregnancy?

Another area of need is helping people after they’re released from the hospital. Hospital stays are shorter, and we need to educate our patients about the signs and symptoms that are worrisome and should prompt them to talk to their doctors—like new headaches, swelling that is new or worsening, or vision changes.

One thing we’ve learned from the pandemic is that telehealth can play a big role in monitoring people, reassuring some and identifying others who need to come back to the hospital. One project I’m working on is looking at monitoring people postpartum with a wearable device that gives us blood pressure measurements continuously. That might help us detect early warning signs in someone who might need more care, either by returning to the hospital or having a nurse visit them at home.

What are some encouraging developments in this area of medicine?

NAB: We’re seeing some government policy changes, like the Black Maternal Health Momnibus Act of 2021 that is aimed at improving overall maternal health, especially among minorities and veterans. It created a lot of funding for research in this area.

It’s exciting that so many people are more aware of these issues now. I’ve been fighting this fight for 15 years, but we need to keep moving forward because there are so many questions, and the ripple effects on the whole family are profound. 

What if you have a stroke two days postpartum? What happens to the baby? The other children? It’s catastrophic for so many people and this is someone in the prime of their life.

These are complications we can potentially prevent, so it’s a great time to be in this field. There’s so much opportunity.