Epigenetics, Oxytocin and Mother-Infant Attachment

Lauren Walsh
Post date: 
May 11, 2015

It is well established that a mother’s mood can have a strong impact on how she interacts with her baby. For Dr. Aleeca Bell, a passion for mothers, babies and the birth experience has driven her research on the neurohormone oxytocin and how it impacts mother-infant interaction.

Bell, nurse midwife and assistant professor in the department of Women, Children and Family Health Science at the University of Illinois at Chicago (UIC), has concerns over the cultural shift away from normal physiological birth toward an experience that is highly technological.

“I wanted to know if a positive birth experience and having a well-regulated oxytocin system could help protect mothers from postpartum depression and anxiety, as well as promote more nurturing maternal behavior,” said Bell. “As health providers, we have opportunities during pregnancy, childbirth, and early postpartum to teach and empower women in their transition to motherhood.”

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Psychosocial risk factors for postpartum depression include a prior history of depression, poor social support, and high stress, but these factors apply to many women. Bell is examining oxytocin, a neurohormone with multiple purposes during childbirth, as another possible cause.  Oxytocin is critical for labor and breastfeeding, buffering stress, promoting a positive mood and forming and strong mother-baby attachment. 

“If a mom is stuck in a repeatedly anxious or depressed mode their baby learns that the world is not predictable or safe, which can impair the baby’s attachment,” explains Bell. “The longer this behavior persists, the greater the possibility of negatively affecting that child’s emotional, social, and physical development.”

In 2011 Bell received funding through the UIC Center for Clinical and Translational Science KL2 Scholar Award. The award provided 75 percent protected research time to launch a retrospective epidemiological study and a case-control study using the rich- but costly- 1991 United Kingdom Avon Longitudinal Study of Parents and Children (ALSPAC) population database.

The study revealed two key pieces of evidence. The first was epidemiologic findings in over 5,000 women demonstrating that a positive birth experience was associated with less maternal anxiety and healthier mothering behaviors through the first year after birth. Qualitative research has shown that a positive birth experience involves feeling respected, supported, and cared for by the medical staff and providers, as well as being involved in decision-making. 

“When a birth is very difficult or complicated, women heal quicker emotionally when they have felt respected, supported and nurtured,” explained Bell. She hypothesizes that for certain women, such as those with a dysregulated oxytocin system, how their body physiologically reacts to a negative birth experience may impact their mothering behavior.

The second line of evidence suggests that the oxytocin receptor gene (OXTR) may be a genetic-epigenetic biomarker of postpartum depression. While a person’s DNA structure never changes, epigenetics is the system of how genes are turned on, off, up or down, which can affect their overall expression. Changes in epigenetics occur naturally, but can also be influenced by factors including age, environment, lifestyle and disease conditions.   

Working with epigeneticist Dr. Jessica Connelly, and using ALSPAC’s DNA bank, Bell’s team compared the DNA of depressed and non-depressed mothers.  They found that higher DNA methylation- an epigenetic marker- of the OXTR was associated with greater risk of postpartum depression in women with a specific OXTR genetic profile who were not depressed during pregnancy.

Based on these findings, an epigenetic hormonal predictor of postpartum depression risk could allow for early interventions. This is the foundation of Bell’s future research.

“I would like to conduct a prospective clinical study replicating and advancing our findings of a potential biomarker by examining the epigenetic marks predictive of depressive symptoms immediately before and after birth,” said Bell.

Bell also hopes that a positive birth experience prompts women to fall in love with their babies on an emotional and physiological level, especially important for at-risk women with multiple psychosocial stressors. She would also like to demonstrate that a multisensory behavioral intervention, developed by UIC’s Dr. Rosemary White-Traut, can improve mother-infant synchrony in at-risk women. The intervention includes teaching women to be sensitive to their baby’s cues, speaking gently, gazing eye-to-eye, and rocking.

“The key to a healthy mother-baby relationship is a mom’s consistent ability to pays attention to her baby’s cues and adjust her behavior to synchronize with the baby’s needs,” says Bell. “The baby will respond with more alertness and readiness to interact, which is typically very satisfying for parents.”

Aleeca Bell is supported in part by the University of Illinois Center for Clinical and Translational Sciences KL2 Scholar Award via the National Center for Advancing Translational Sciences, National Institutes of Health  (KL2TR000048).  The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.