Hormones related to body composition during pregnancy are linked to babies’ mental health

Researchers from Oregon Health & Science University’s Center for Mental Health Innovation have discovered why increased body fat during pregnancy is linked to a higher risk of mental disorders in offspring.

The study, published recently in the magazine Brain, behavior and immunityinvestigated whether the concentrations of two important hormones related to fat mass, adiponectin and leptin, in the blood of pregnancy or in the cord blood can predict mental disorders in babies. Leptin, a hormone that helps regulate appetite, and adiponectin, a hormone that helps regulate glucose levels and breakdown of fat, are both crucial for fetal development.

While there is increasing evidence of a link between obesity during pregnancy and the mental health of offspring, increasingly clearthe mechanisms underlying this relationship are not yet understood. This is the first study to demonstrate the link between the two hormones and behavioral outcomes of offspring.

“The link between the metabolic state of the expectant parent during pregnancy and the mental health of the offspring is relatively new, and there is very little research to explain the connection,” said Elinor Sullivan, Ph.D., a professor of psychiatry in the OHSU School of Medicine and lead author of the study. “The thought is that metabolic state may influence the in-utero environment, which can shape the fetal brain and its development.

“By identifying new biomarkers, we can predict at a very early stage which children are at risk of common mental disorders, such as ADHD and anxiety disorders. This allows us to intervene in a targeted and early manner.”

Biomarkers, or measurable properties in the body, can serve as an early warning system for underlying diseases or conditions and are a valuable tool to better understand an individual’s health.

Led by Sullivan and Hanna Gustafsson, Ph.D., researchers collected data from a cohort of more than 300 pregnant people and their children, collecting second-trimester blood samples from the parent and an umbilical cord blood sample at birth. The offspring were brought in for evaluation at 6 months of age, at which time researchers administered standard behavioral tests to examine behaviors used to regulate emotions, which are strong indicators of risk for early-life mental disorders.

The findings suggest that lower levels of the hormone adiponectin in the parents’ bloodstream and higher concentrations of the hormone leptin in cord blood may be novel biomarkers of their offspring’s risk for mental disorders.

Researchers say identifying these biomarkers could have significant potential for early intervention for children at risk for a range of mental health disorders, and suggest that identifying children at risk may be possible earlier than commonly thought — at or even before birth. What’s more, these biomarkers can be measured in a clinical setting using standard, inexpensive tools, and can be assessed using a single test that is easy to interpret.

The next step for the research team will be to test interventions aimed at reducing the risk of children’s mental health problems and supporting parents during the perinatal period. There is promising evidence that teaching parents practical skills during pregnancy can help support the health of both parent and child — for example, learning how to swaddle and soothe a crying baby, providing information about typical infant crying patterns, and offering mindfulness techniques to help them manage their own emotions while caring for a baby.

“Weight can be a complex and sensitive topic for pregnant individuals, and our goal as clinicians is to help patients take the best care of themselves and their developing babies,” said Jamie Lo, MD, MCR, an associate professor of obstetrics and gynecology at the OHSU School of Medicine who specializes in maternal-fetal medicine. “These findings provide an opportunity to intervene early in pregnancy to potentially improve health outcomes in children.”

Lo also emphasizes the importance of access to quality prenatal care, including nutrition and healthy lifestyle education during pregnancy and before conception, as critical to optimizing the health of pregnant women and their babies.

Looking ahead, Sullivan says more research is needed to better understand the nature of these associations and whether behavioral health outcomes persist throughout childhood. The research team plans to follow the subjects for up to 5 years to determine how these factors predict long-term risk and clinical diagnoses.

“While this is an exciting first step, there is still so much to learn, including what role social determinants of health may play,” Sullivan said. “We look forward to continuing our research and supporting improved care for birthing parents and their children.”