Women’s heart health strongly related to pregnancy outcomes
A strong and graded relationship was found between specific CV risk factors presenting in women before pregnancy and pregnancy outcomes, researchers reported in the European Journal of Preventive Cardiology.
“Individual cardiovascular risk factors, such as obesity and hypertension, present before pregnancy have been associated with poor outcomes for both mother and baby,” Sadiya S. Khan, MD, MSc, assistant professor of preventive medicine (epidemiology) and medicine (cardiology) at Northwestern University Feinberg School of Medicine, said in a press release. “Our study now shows a dose-dependent relationship between the number of risk factors and several complications. These data underscore that improving overall heart health before pregnancy needs to be a priority.”
The cross-sectional analysis included 18,646,512 pregnancies (mean maternal age, 29 years) from data from all live births and fetal deaths after 20 weeks’ gestation in the U.S. from the National Center for Health Statistics. Individual-level data from births to women (aged 15-44 years) were pooled from 2014 to 2018. Researchers created a risk factor score through assigning prepregnancy CV risk factors such as BMI less than 18.5 kg/m2 or greater than 24.9 kg/m2, smoking by maternal self-report, hypertension and diabetes; each patient received one point if a risk factor was present and zero points if it was absent.
One or more prepregnancy CV risk factors were present in more than 60% of women, with 52.5% presenting with one, 7.3% presenting with two, 0.3% presenting with three and 0.02% presenting with four.
Compared with women without any CV risk factors, those with one or more CV risk factors had lower educational attainment (79.5%-85.3% vs. 88.7%), less receipt of prenatal care (97.8%-98.5% vs. 98.7%), higher multiparity prevalence (64.4%-69.3% vs. 56.9%) and higher prior spontaneous or induced pregnancy loss prevalence (27.4%-46% vs. 23.4%).
Compared with women without any CV risk factors, women with one (RR = 1.12; 95% CI, 1.09-1.15), two (RR = 1.86; 95% CI, 1.78-1.94), three (RR = 4.24; 95% CI, 3.85-4.68) or four (RR = 5.79; 95% CI, 4.07-8.23) prepregnancy risk factors had higher risk for maternal ICU admission.
Women with at least one prepregnancy CV risk factor also had elevated risk for preterm birth, low birth weight and fetal death compared with women with no risk factors, with the risk increasing along with the number of risk factors, according to the researchers.
Except for nonideal BMI, individual risk factor score components were directly associated with adverse pregnancy outcomes.
According to the researchers, individual-level CV risk factor assessment should be applied before pregnancy while preventions may have greater benefits than during pregnancy.
“These findings argue for more comprehensive prepregnancy cardiovascular assessment rather than focusing on individual risk factors, such as BMI or blood pressure, in isolation,” Khan said in the release. “In reality, not all pregnancies are planned, but ideally we would evaluate women well in advance of becoming pregnancy so there is time to optimize their health.”