Up to 1 in 7 pregnancies may be impacted by negative cardiovascular-related health problems, even in patients without heart disease, according to a recent study published in Circulation, the flagship journal of the American Heart Association.1
There were over 56,000 pregnancies included in the analysis, 15% of which were impacted by cardiovascular conditions including stroke, heart attack, blood clots, heart failure, hypertensive disorders, and maternal death. According to researchers, this highlights a need for patients to engage with health care providers before, during, and after pregnancy.1
Key takeaways:
- Up to 15% of pregnancies were affected by cardiovascular complications, including stroke, blood clots, and hypertensive disorders.
- Data from over 56,000 pregnancies at Mass General Brigham revealed increasing rates of pregnancy-related heart health issues.
- Hypertensive disorders of pregnancy were the most common complication, impacting 12% of pregnancies.
- Preexisting conditions such as obesity, hypertension, and diabetes significantly contributed to cardiovascular risk.
- Researchers emphasized early prevention and heart-healthy lifestyle changes before, during, and after pregnancy.
“Most of these health risk factors can be prevented through lifestyle changes or medication. Yet, many of my patients aren’t even aware they have these conditions or that they’re at risk,” said Stacey E. Rosen, MD, FAHA, volunteer president of the American Heart Association.1
Assessing cardiovascular complications
The study was conducted to evaluate trends in cardiometabolic comorbidities during pregnancy.2 Data was obtained from Mass General Brigham (MGB), a health care network including 11 tertiary care and community hospitals. Pregnant patients visiting MGB from 2011 to 2019 were included in the analysis.
Exclusion criteria included being aged under 18 years or at least 60 years, induced abortion, spontaneous abortion, missing gestational age, pregnancy under 20 weeks’ gestation, and ectopic pregnancy. Pregnancy encounters were independently verified by 2 physicians.2
Unstructured clinical notes were assessed to determine gravidity, parity, and estimated gestational age. Pregnancy episodes were defined as the time between the last estimated menstrual period and the date of delivery.2
Cardiovascular complications during pregnancy included the composite of major adverse cardiovascular events (MACEs), maternal death, and hypertensive disorders of pregnancy (HDP). Baseline clinical variables included vital signs, demographic data, smoking status, prevalent comorbidities and disease, and alcohol use.2
Preexisting conditions
There were 56,833 pregnancies among 38,996 patients aged a mean 32±5 years at the start of pregnancy included in the analysis. Of pregnancies, 92% were live birth, 0.1% mixed birth, 1% stillbirth, and 7% unclassified. The mean gravidity and parity were 2.5±1.7 and 1.2±1.1 pregnancies, respectively.2
Preexisting obesity was reported in 12% of pregnancies, preexisting diabetes in 3%, preexisting hypertension in 8%, and preexisting hyperlipidemia in 10%. A mean maternal body mass index of 26.2±5.9 kg/m2 was reported.2
Four percent of patients presented with preexisting cardiovascular disease, with venous thromboembolism in 2%, transient ischemic attacks in 0.5%, and heart failure in 1%. Additionally, 0.7% of pregnancies were impacted by prevalent arrhythmias and 0.1% by myocardial infraction.2
Pregnancy-related cardiovascular events
An incident cardiovascular event was reported in 15% of pregnancies, 12% of which occurred intrapartum and 2% occurred postpartum. Four percent of pregnancies were impacted by MACEs, the most common of which was venous thromboembolism in 2%.2
- HDP was reported in 12% of pregnancies
- Chronic hypertension in 5%
- Preeclampsia in 8%
- Gestational hypertension in 2%
- And maternal death in only 0.01%
An increase in pregnancy-related cardiovascular complications was reported over time, from 11% in 2001 to 13% in 2019. Increasing incident HDP rates were also reported, though no significant trend in incident MACEs was identified.2
Overall, the data highlighted a significant burden of cardiovascular complications in pregnancy, with a significant increase over the past 2 decades. Investigators concluded that the pregnancy period is a crucial time to implement primary prevention strategies.2
“Starting before pregnancy and continuing after birth, there are valuable opportunities to make heart-healthy choices that can help prevent cardiovascular disease and support long-term wellness,” said Rosen.
References
- Risk factors for cardiovascular disease negatively impact health during, after pregnancy. American Heart Association. October 6, 2025. Accessed October 8, 2025. https://www.eurekalert.org/news-releases/1100836.
- Lau ES, D’Souza V, Zhao Y, et al. Contemporary burden of cardiovascular disease in pregnancy: insights from a real-world pregnancy electronic health record cohort. Circulation. 2025. doi:10.1161/CIRCULATIONAHA.125.074692
