Infants born to mothers with depressive symptoms immediately after delivery had a substantially higher risk of dying before their first birthday, according to researchers involved in a Rutgers-led study of more than 414,000 births in New Jersey.
The study , published in JAMA Network Open, linked New Jersey birth records from 2016 through 2020 with infant death records through 2021. Researchers found an infant mortality rate of 7.2 deaths per 1,000 births among infants whose mothers reported depressive symptoms, compared with two deaths per 1,000 births among infants whose mothers didn't report these symptoms.
After researchers accounted for maternal and infant demographic and socioeconomic factors, infants whose mothers had depressive symptoms had nearly three times the risk of death before the age of 1 compared with their counterparts. This association remained when researchers looked separately at mothers by race and ethnicity, education and insurance status, as well as babies born at full term, as well as those born prematurely.
"What stood out to us was how consistent the pattern was," said Rebecca Woofter , a postdoctoral associate in the Department of Health Behavior, Society and Policy at the Rutgers School of Public Health and the lead author of the study. "We found an association between maternal depressive symptoms and infant mortality across many different groups of mothers and infants. These findings don't mean that maternal depression is causing infant deaths, but it does tell us there is an important relationship here that we need to understand much better."
New Jersey provided a useful setting for the research because hospitals in the state are required to screen patients for depressive symptoms after delivery and before they leave the hospital. The screening is conducted with the Edinburgh Postnatal Depression Scale , a widely used questionnaire designed to identify symptoms of depression in pregnant and postpartum people. The results of the screening are documented in the child's birth record.
Because of New Jersey's universal mental health screening, the study didn't rely on clinical diagnoses of depression. The researchers said that matters because many people experiencing depressive symptoms are never formally diagnosed.
The researchers also looked at the leading causes of infant death in New Jersey. Maternal depressive symptoms were associated with higher risks of infant deaths related to prematurity, perinatal conditions, congenital malformations and chromosomal abnormalities and sudden infant death syndrome.
Exactly what explains the connection isn't yet known.
Maternal depression previously has been linked with adverse birth outcomes and changes in health behaviors and health care use. Depression also is closely tied to social and economic conditions that can affect the resources available to families. In some cases, the relationship may run in the other direction: A mother who learns that her newborn has a serious health condition may experience depressive symptoms as a result.
The researchers said the new study shows an association and cannot establish whether maternal depressive symptoms cause infant mortality. Although they accounted for a wide range of maternal and infant characteristics, other unmeasured factors could help explain the findings.
Still, the results point to maternal mental health as an important part of the larger conversation about infant health.
"This study underscores the connection between maternal health and infant health and the need for continuity of health care for both mothers and infants following delivery," Woofter said.
The study also points to gaps between depression screening and mental health care. Although professional medical organizations, including the American College of Obstetricians and Gynecologists, recommend screening for depression during the perinatal period, screening practices vary. Even when depressive symptoms are identified, screening doesn't necessarily lead to a diagnosis, referral or treatment.
"Screening gives us information at a point when almost every mother is still in the hospital," said Slawa Rokicki , an assistant professor in the Department of Health Behavior, Society and Policy at the Rutgers School of Public Health and the principal investigator of the study. "But identifying symptoms is only the first step. Screening by itself isn't treatment. It must also be accompanied by effective referrals and access to appropriate treatment."
Woofter conducted the research with Rokicki; Mark McGovern, an associate professor in the Department of Health Behavior, Society and Policy; and Naomi Abe, a pediatrician in the Department of Emergency Medicine at the University of California, San Francisco.
The research was funded by the New Jersey Integrated Population Health Data Project at the Rutgers Center for State Health Policy.
