Psychosocial stress during pregnancy may raise blood pressure after birth

Psychosocial stress during pregnancy could lead to higher blood pressure during the first year postpartum according to research from Keck School of Medicine of USC.

The study, published in Hypertension and supported by the National Institutes of Health, investigated whether mothers who reported higher perceived stress and depressive symptoms during pregnancy, developed higher blood pressure in the four-year period after birth. The findings showed higher stress and depressive symptoms during pregnancy were associated with greater blood pressure during the first year postpartum, but associations diminished thereafter.

Pregnancy is a complex time where women experience different physiological changes. This study is building on maternal health research to understand how stressors impact women's lives and their health after pregnancy."

Noelle Pardo, the lead author of the study and third year doctoral student in the Department of Population and Public Health Sciences, Keck School of Medicine

The study included data from 225 mothers from the MADRES pregnancy cohort which primarily consists of Hispanic women, and low-income participants living in Los Angeles. Hispanic women have a high burden of cardiovascular risk, and there is growing evidence linking psychosocial stressors to poor cardiovascular health, which is a leading cause of death among women in the US.

In addition to prenatal psychosocial stress, Pardo explored whether prenatal neighborhood social cohesion was a protective factor for postpartum hypertension risk-a first investigation of its kind. This refers to the sense of connection and trust a pregnant woman experiences in her community. According to her findings, social structures that promoted cohesion may have had a positive influence throughout pregnancy into the postpartum period and were associated with lower blood pressure.

"We chose social cohesion as a variable to understand how connected the participants felt to their community. Right now, there aren't many programs or policies that help foster cohesion, yet such interventions may serve as a novel protective factor," she says.

According to Pardo, maternal health research has mostly focused on pregnancy outcomes, with limited studies investigating the mother's health after birth. Yet, her results have shown how crucial this research is in identifying conditions rooted in pregnancy.

The real-world application of this study calls for the identification of vulnerable individuals in the pregnant population, offering interventions to reduce stress and depressive symptoms. Similarly, it emphasizes the importance of monitoring women's health after birth, through the provision of additional hypertension screenings among mothers who experience higher prenatal stress.

"Pregnancy may be important in determining a woman's long term cardiovascular health. Similarly, more research is needed to determine how different exposures during pregnancy can convey future cardiovascular risk to women," she concludes.