High stress levels in pregnant women raise risk of low birth weight in newborns: Study

High stress levels in pregnant women can lead to lower birth weight and lower weight-for-length ratio in newborns, besides increasing the mothers' risk for postpartum depression, a study from Bengaluru published in The Lancet Regional Health has shown.

Currently, mental health of pregnant women is not part of health checkups in government or private health facilities.

The study, co-authored by researchers from the Public Health Foundation of India (PHFI), Nimhans and Maastricht University, was conducted among 230 pregnant women recruited across government hospitals, BBMP maternity homes and health centres. The participants were aged between 18 and 45 years.

Researchers measured the women's stress hormone cortisol. Women whose cortisol levels were above the group's mean levels were twice as likely to deliver a low birth-weight baby (weighing less than 2.5 kg) compared to women with lower cortisol levels. Low birth weight increases babies' risk of complications.

Similarly, women with higher cortisol levels were twice as likely to have newborns with a lower weight-for-length ratio, that is, weight inadequate for their total height.

"Stress does occur during pregnancy. But when there's additional stress due to factors like lack of family support or pregnancy-related complications, cortisol secretion increases. Additional cortisol can enter the placenta and cause harms such as tissue damage and reduced oxygen availability for the baby. Elevated cortisol can also reduce blood flow to the uterus and hinder normal growth," Prafulla Shriyan of PHFI, lead author of the study, told DH.

The study also found that women with higher cortisol levels were 2.3 times more likely to have postpartum depressive symptoms than those with lower cortisol levels.

"During antenatal checkups and after delivery, the focus is only on some physical indicators and birth outcomes. The woman's well-being or family status is not in focus," said Shriyan.

Dr Giridhar Babu, co-author of the study, said, "The National Health Mission can be strengthened by adding universal screening of mental health symptoms among pregnant women. By systematically collecting data on the prevalence, risk factors and outcomes of poor mental health status among them, the health system can gain insights into effective interventions as well as strategies for prevention."