Effect of negative relationships on health of women postpartum

Pregnancy brings a variety of changes to the body and its systems, including the autonomic system. A division of the nervous system that controls organ muscles and partially mediates stress response, it’s believed that the autonomic nervous system (ANS) develops an increase in sympathetic activity and a decrease in parasympathetic activity during gestation. This normal change allows the body to better support fetal growth. This shift to the autonomic system can reduce vagally mediated heart rate variability (HRV), or the variation of time between heartbeats.

Complications arise because lower HRV indicates that the body is not as equipped to deal with and recover from stress. An abnormal adaptation of HRV is correlated with adverse pregnancy outcomes, such as fetal neural developmental disorders and maternal preeclampsia. Psychological and emotional stress may exacerbate these negative outcomes, and romantic relationship stressors are known to lead to a significant reduction in HRV.

While this shift in the ANS has been studied across different stages of pregnancy, little is known about the ANS system adjustments made to the mother’s body during the postpartum stage. In addition, science lacks clarification on the influence that negative romantic relationships may have on the body’s ability to return to normal ANS and HRV function postpartum.

Lisa Christian, PhD, associate professor of Psychiatry at The Ohio State University College of Medicine, tested the effect of relationship quality on depression and HRV in women following their third trimester of pregnancy and up to one year postpartum. As senior author, she partnered with lead author Ryan Linn Brown, graduate student in Psychological Sciences at Rice University, co-author Christopher Fagundes, PhD, associate professor of Psychological Sciences at Rice University and co-author Julian Thayer, PhD, professor of Psychological Science at University of California, Irvine.

“We know little about whether partner relationship quality concurrently impairs autonomic nervous system recovery in the postpartum period,” says Ryan. “Our primary aim with this research was to characterize the changes in vagally mediated HRV from the third trimester to 12 months postpartum. Understanding the biological mechanisms underlying successful autonomic adaptation in the postpartum period may serve as a foundation to build future interventions for new mothers.”

They used the Positive and Negative Quality in Marriage Scale, which globally measures the participants’ perception of the extent to which there are positive and negative aspects of their romantic relationship. They measured depressive symptoms via the Center for Epidemiologic Studies Depression Scale, and monitored HRV throughout the experiment.

“We characterized the longitudinal trajectories and influence of negative partner relationship qualities on people's vagally mediated HRV and depressive symptoms across five time points up to 12 months postpartum,” says Dr. Christian.

The study found the only significant increase in vagally mediated HRV occurred between the third trimester and four to six weeks postpartum. This was consistent with previous studies that found HRV to increase to more normal levels postpartum, also confirming that changes to HRV diminish by three months after birth. This autonomic recovery was found to be hindered by negative relationships, with worse outcomes between four to eight months postpartum. Across all time points, reported negative relationships also resulted in a higher rate of severe depressive symptoms than those who reported more positive relationships.

The authors suggest that further studies should be carried out to address the limitation of diversity among their sampled population. In addition, future designs should increase the sample size. Both of these changes will increase the generalization capacity of the findings.

“Despite these limitations, our study begins to elucidate the mechanisms through which poorer quality relationships can negatively influence postpartum health,” says Dr. Christian. “Understanding the psychological conditions and biological mechanisms that underlie worse postpartum recovery can enable future researchers to use interventions to reduce a person’s risk of autonomic dysfunction in the postpartum period.”

One intervention that the team anticipates to be useful for balancing the autonomic system are mindfulness-based stress reduction techniques. 

“Mindfulness-based relationship enhancement fosters more attention and awareness of one’s experience in the present moment,” says Dr. Christian. “This intervention may be ideal for combating the decrements in vagally mediated HRV that are associated with negative qualities of one’s partner relationship.”

These findings will aid clinicians in guiding mothers throughout pregnancy, providing women with healthier pregnancies physically and mentally.