More Data Needed on Lifestyle Interventions for Postpartum Blood Pressure Control

Hypertensive disorders of pregnancy such as preeclampsia and gestational hypertension occur in up to 10% of pregnancies and are associated with a three-fold increased risk of chronic hypertension and up to two-fold increased risk of cardiovascular disease when compared with healthy pregnancies. While the year after pregnancy is a critical time to address hypertension risk with lifestyle changes (healthy diet and exercise), the effects of lifestyle interventions on postpartum blood pressures are not well documented.

A new  study has found that there are few relevant studies on the effects of lifestyle interventions on postpartum blood pressures. Of the nine relevant publications, none reported a significant intervention effect on blood pressure. However, most interventions were associated with improvements in other outcomes, such as weight loss. The research team also found that Black women were underrepresented in studies – only one study included a majority of Black women – despite the fact that Black women are disproportionately affected by high blood pressure during and after pregnancy.

“Overall, the evidence for postpartum lifestyle interventions to reduce blood pressure is limited to a handful of studies, which are characterized by small sample sizes and a lack of racial diversity. Additional research with larger samples, more diverse populations, and intermediate outcomes is warranted,” said corresponding author Mara Murray Horwitz, MD, assistant professor of medicine at the School.

The researchers searched for English language publications about lifestyle interventions evaluated in postpartum individuals, with measured blood pressure as an outcome. Two authors screened every article to identify the relevant studies, then extracted data from them. The study team then examined study and sample characteristics (location, and number and race/ethnicity of participants), intervention characteristics (diet or exercise, in-person or virtual), and blood pressure outcomes. Finally, they analyzed the blood pressure effects in the studies overall, and then restricting to those studies that enrolled only people with a recent diagnosis of preeclampsia. 

According to the researchers, many factors make it difficult for postpartum individuals to engage in healthy lifestyle changes, such as: physical recovery from childbirth, discontinuities in health care and health insurance after delivery, competing demands such as childcare and returning to work, and social and financial stressors that are common in the postpartum period. “Barriers to postpartum care disproportionately affect Black and Brown individuals and those with low incomes, perpetuating healthcare inequities. Much work needs to be done to make more intense or longer-duration lifestyle change feasible for all people during the postpartum period. I submit that, if we truly want to support equitable and sustainable healthy lifestyles after pregnancy, multi-level reform is necessary,” said Murray Horwitz, who also is a primary care physician at Boston Medical Center.

These finding appear online in the Journal of Hypertension.