Pregnancy complications may raise women's risk of heart disease for life

Major pregnancy complications, such as preeclampsia and preterm birth, should be recognized as lifelong risk factors for women's heart disease, new research suggests.

Women who experience any of the five major pregnancy complications have an increased risk of ischemic heart disease up to 46 years after delivery, says the study published Wednesday in the BMJ.

The five complications are: preterm delivery (less than 37 weeks gestation), small baby for gestational age at birth, preeclampsia (a blood pressure disorder), other blood pressure disorders of pregnancy, and gestational diabetes.

"Women with adverse pregnancy outcomes should be considered for early preventive evaluation and long-term risk reduction to help prevent the development of ischemic heart disease," the study authors said in a journal news release. Dr. Casey Crump, from the Icahn School of Medicine at Mount Sinai in New York City, led the research team.

Nearly one-third of women experience an adverse pregnancy outcome, the authors said in background notes. Heart disease is the leading cause of death among women worldwide.

For the study, U.S. and Swedish researchers identified more than 2.1 million women in Sweden with no history of heart disease. Each had given birth to a single live infant between 1973 and 2015 at an average age of 27.

Using medical records, the researchers tracked cases of heart disease from delivery date through 2018. This was an average follow-up time of 25 years.

They considered the mothers' age, number of children, education, income, body mass index, smoking and history of high blood pressure, diabetes or high cholesterol.

Heart disease was diagnosed in more than 83,000 -- or almost 4% -- of women at an average age of 58.

The researchers found that in the 10 years after delivery, relative rates of heart disease rose 1.7-fold in those with a history of preterm delivery and 1.5-fold in women with preeclampsia. Moreover, they rose twofold in women with other high blood pressure disorders of pregnancy. In addition, risk of heart disease rose 1.3-fold in those with gestational diabetes and 1.1-fold in those who delivered a small-for-gestational-age infant.

Women who had experienced several adverse pregnancy outcomes showed further increases in risk.

These risks remained significantly elevated 30 to 46 years after delivery. They were only partially explained by shared genetic or environmental factors within families, the researchers noted.

The study can't prove a direct cause and effect relationship, however.

More information

The U.S. Centers for Disease Control and Prevention has more on women and heart disease.