Summary: Adults who experienced parental divorce in childhood show significantly lower oxytocin levels than adults from intact families, a difference that may be linked to later attachment and social difficulties.
Source: Baylor University
Lower Oxytocin Levels Found in Adults Who Experienced Parental Divorce
A study led by researchers at Baylor University found that adults who experienced parental divorce during childhood had substantially lower concentrations of oxytocin—the neurohormone often called the “love hormone”—compared with adults whose parents remained together. Because oxytocin plays a central role in bonding, parenting, social behavior and stress regulation, the reduced levels observed in this group may help explain persistent difficulties with attachment and close relationships in adulthood.
Background: Oxytocin and Early Life Stress
Oxytocin is produced in the brain and released during bonding experiences such as childbirth, breastfeeding, sexual intimacy and affectionate touch. Prior research links oxytocin to emotional attachment, parental sensitivity and anxiety regulation. Animal studies have shown that early maternal separation or parental loss can alter oxytocin functioning and produce long-term changes in social, sexual and stress-related behaviors. Human studies of parental divorce have documented higher rates of mood disorders, substance use, and relationship difficulties later in life, but the biological mechanisms mediating these effects have been less clear.
The Study: Methods and Measures
The study, published in the Journal of Comparative Psychology, examined urinary oxytocin in 128 adults aged 18 to 62 recruited at two southeastern U.S. institutions. Participants completed questionnaires assessing parental history (including whether and when parents divorced), attachment style, perceptions of parental care and warmth, and current social functioning. After answering the questionnaires, participants provided a urine sample that was assayed for oxytocin concentration.
Key Results
Among the sample, 27.3% reported experiencing parental divorce during childhood, with the average age at divorce around nine years. Urinary oxytocin concentrations were significantly lower in adults who experienced parental divorce (mean = 3.70, SEM = 0.73) compared with those who did not (mean = 8.00, SEM = 1.21), a difference reaching statistical significance (p = .016). Lower oxytocin levels also correlated with several self-reported measures of attachment, including less confidence in relationships, greater discomfort with closeness, and less secure relationship styles.
Additional Observations
Participants who reported parental divorce also tended to rate their parents as less caring and more indifferent, and to report higher levels of paternal abuse. In turn, these adults rated their own caregiving style as less sensitive and emotionally close. The findings align with animal models suggesting that early parental separation can suppress oxytocin activity, with downstream consequences for social behavior and emotional regulation.
Implications and Future Directions
These results suggest a potential biological pathway linking childhood parental divorce to adult attachment and social functioning: reduced oxytocin levels. Understanding how the timing of parental divorce, the quality of parent-child relationships, and other early-life stressors interact with oxytocin biology will be important next steps. As the study’s lead author, Maria Boccia, Ph.D., notes, determining whether the child’s age at the time of divorce influences oxytocin outcomes is a pressing question for future research.
Funding and Collaboration
This research was supported by a grant from the National Institutes of Health. Co-researchers included collaborators from Gordon-Conwell Theological Seminary (Charlotte, N.C.) and the departments of surgery and psychiatry at the University of North Carolina–Chapel Hill.
Abstract (Condensed)
Oxytocin supports social bonds and emotional attachment and may mediate effects of early-life experiences on adult social motivation. In this study of 128 adults ages 18–62, urinary oxytocin concentrations were substantially lower in individuals who experienced parental divorce in childhood compared with those who did not. Lower oxytocin correlated with attachment-related measures, suggesting that parental divorce may adversely affect oxytocin functioning and contribute to long-term differences in attachment and social behavior.
Original research: “Parental divorce in childhood is related to lower urinary oxytocin concentrations in adulthood” by Boccia, M. L., Cook, C., Marson, L., & Pedersen, C., Journal of Comparative Psychology. (Closed access, DOI: 10.1037/com0000248)