HealthDay News — Preterm delivery is associated with increased maternal risk for ischemic heart disease (IHD), with increased risk seen through more than 40 years of follow-up, according to a study published in the July 7 issue of the Journal of the American College of Cardiology.
Casey Crump, M.D., Ph.D., from the Icahn School of Medicine at Mount Sinai in New York City, and colleagues conducted a national cohort study of all 2,189,190 women with a singleton delivery in Sweden from 1973 to 2015, with follow-up for IHD through 2015.
The researchers found that 2.3 percent of women were diagnosed with IHD in 47.5 million person-years of follow-up. The adjusted hazard ratio for IHD associated with preterm delivery was 2.47 in the 10 years following delivery, with further stratification to 4.04, 2.62, 2.30, and 1.47 for extremely preterm, very preterm, late preterm, and early term, respectively, compared with full term. After additional follow-up, these risks declined but remained significant (adjusted hazard ratios, 1.86, 1.52, and 1.38 for preterm versus full term at 10 to 19, 20 to 29, and 30 to 43 years, respectively). The findings did not appear to be attributed to shared genetic or environmental factors within families.
“The findings suggest that preterm and early-term delivery are important independent risk factors for the development of IHD, and that the associated risks may persist up to 40 years later,” the authors write.