Pregnancy Complications Signal Lifelong Heart Disease Risk, Study Finds

A Swedish study tracking more than two million women over four decades has found something that should reshape how doctors think about pregnancy: certain complications during labor and delivery are powerful predictors of heart disease that can strike years or even decades later.

The research, published in the BMJ in early 2023, examined women who gave birth between 1973 and 2015 and had no prior history of heart disease. About three in ten experienced at least one significant pregnancy complication. The findings were stark. Women who developed gestational diabetes—high blood sugar during pregnancy—faced a 54 percent higher risk of ischemic heart disease, the kind caused by narrowed blood vessels that starve the heart of oxygen. Preeclampsia, a dangerous spike in blood pressure during pregnancy, raised the risk by 30 percent. Other high blood pressure disorders during pregnancy doubled the risk entirely. Delivering before 37 weeks increased the danger by 72 percent. Even delivering a baby with low birth weight carried a 10 percent elevation in lifetime heart disease risk. Women who experienced multiple complications across pregnancies saw their risks compound further.

The mechanism remains incompletely understood, but cardiologists and maternal health specialists offer a working theory: pregnancy acts as a kind of stress test on the body. The dramatic physiological changes—increased blood volume, altered metabolism, hormonal shifts—can expose underlying vulnerabilities in women who carry certain risk factors. When complications occur, they may cause lasting damage to blood vessels and heart tissue that persists long after the baby is born and the pregnancy ends.

This matters urgently because heart disease is the leading cause of death among American women, accounting for one in five female deaths. Yet the connection between what happens in the delivery room and what happens in the cardiac ward decades later remains largely invisible in clinical practice. Most standard risk calculators that doctors use to assess a woman's heart disease danger include no mention of pregnancy complications. The American Heart Association recommends that all health care providers take a detailed pregnancy history when evaluating women's cardiovascular risk, but this guidance is inconsistently followed, particularly in primary care settings where most women receive routine care.

The gap widens after delivery. Research suggests that only 30 to 80 percent of women receive a postpartum checkup six to eight weeks after giving birth. Those who experienced gestational diabetes or preeclampsia often leave the hospital without being told they now carry elevated cardiovascular risk. No one connects them with a cardiologist. No one explains that the blood pressure spike or the blood sugar disorder that resolved after delivery was actually a warning signal. They return to their regular lives, their regular doctors, unaware that they have entered a higher-risk category for the disease that kills more American women than any other.

Dr. Casey Crump, one of the study's authors and a professor of family medicine at Mount Sinai, frames the finding as an opportunity: these pregnancy outcomes are early signals that can help identify high-risk women sooner and enable earlier intervention. Dr. Tara Narula, a cardiologist at Lenox Hill Hospital who specializes in women's heart health, describes pregnancy as almost a stress test—a window into a woman's future cardiovascular destiny. Yet most women never hear this from anyone. They are not told to think of their pregnancy complications as anything more than a temporary medical event.

Experts point to shifting demographics as part of the problem. American women are having children at older ages and often already carry one or two cardiovascular risk factors before pregnancy. They may be managing depression, stress, obesity, or other chronic conditions. The pregnancy itself becomes a collision point where multiple vulnerabilities converge. The solution requires coordination that rarely happens: better screening before pregnancy, better treatment during pregnancy, and crucially, a warm handoff from obstetrics to primary care or preventive cardiology after delivery, with explicit conversation about cardiovascular risk reduction in the postpartum months and years.

The stakes are not abstract. Cardiovascular disease is a leading cause of maternal mortality in the United States, which already has a maternal death rate several times higher than other wealthy nations. Experts emphasize that cardiovascular disease is preventable. The tragedy, as one cardiologist put it, is bringing a new life into the world only to have the mother suffer a preventable complication or death. Raising awareness among both physicians and women themselves is the first step toward ensuring that pregnancy complications become not a forgotten footnote but a recognized marker that changes how a woman's health is managed for the rest of her life.