Attachment Quality Buffers the Effect of Prenatal Stress Exposure on Infant Baseline Cortisol Levels

• In Event: 3-209 - Maternal Traumatic Stress Before and During Pregnancy: Pathways to Offspring Development

Integrative Statement

Introduction: Prenatal stress has deleterious effects on multiple indices of early biobehavioral regulation. Theory and research suggest the caregiving environment can mitigate or heighten these negative impacts; for example, observed maternal sensitivity moderates the effect of depression/anxiety during pregnancy on 4-month-old infants baseline cortisol levels (Kaplan, Evans, & Monk, 2008). Early cortisol regulation, a marker of Hypothalamic-Pituitary-Adrenal Axis activity, is a key potential mechanism of risk transmission for a variety of psychosocial and physical health outcomes, with effects that can extend into adulthood. Therefore, the present study evaluated whether mother-infant attachment protects against the negative effects of prenatal stress on infant cortisol levels. Methods: Eighty-two women and their infants (10 to 14 months old; M = 11.90, SD = 1.01) were recruited from the community through flyers posted at social service agencies (e.g., WIC centers) and other business that serve young children in Chicago. Women were mostly of ethnic minority backgrounds (39% Black, 38% Latino) and low SES (60% below the poverty line). About half of the infants were girls (47%) and (55%) lived in two-parent households. Women reported their lifetime and pregnancy exposure to stress and trauma using the Lifetime Trauma Questionnaire – Revised. Infant baseline saliva samples were obtained after informed consent and 5-minutes of mother-infant free play. Cortisol levels were ascertained using ELISA (Salimetrics, LLC). Dyads also completed the Strange Situation Task, the gold standard to assess attachment quality. Two certified clinical psychologists coded videotapes with good inter-rater reliability (85% agreement; kappa = .73, p = .00). Moderation analyses were conducted using Hayes’ PROCESS macro in SPSS 25 and controlling for methodological (time of day) and demographic (maternal education) confounds. Results: Fifty-seven percent of women experienced one or more traumatic/stressful events during pregnancy (0-7 events, M = 1.01), including most commonly serious money problems, emotional abuse or neglect, the death of someone close, a family member sent to jail, and serious physical or mental illness. More than half of the infants (57%) were securely attached, 21% were disorganized, 12% insecure-avoidant, and 10% insecure-resistant. There were no mean differences in pregnancy stress by mother-infant attachment security. The PROCESS model showed the effect of pregnancy stress was moderated by a trend-level interaction with attachment security (b = .03, p = .09); among infants with secure attachment, there was no association between pregnancy stress and baseline cortisol (b = .00, p = .94), but among those who didn’t have a secure attachment (insecure or disorganized), pregnancy traumatic stress predicted lower levels of baseline cortisol (b = -.03, p = .03; See Figure 1). Conclusions: Findings suggest that a secure mother-infant attachment can protect against the negative effects of prenatal stress on infant resting cortisol levels and replicate previous findings, extending them to a larger community sample. While other research suggests that stress and trauma can increase risk for maternal hostility and poor sensitivity, our study highlights the heterogeneous parenting outcomes of women who experience stress during pregnancy and suggest efforts to promote secure mother-infant attachment can ameliorate early HPA axis dysregulation.

Authors

• Cecilia Martinez-Torteya, Universidad de Monterrey
  Presenting Author

• Michelle A. Gilchrist, DePaul University
  Non-Presenting Author

• Alissa C Huth-Bocks, University Hospitals Cleveland Medical Center
  Non-Presenting Author

• Matthew Sorenson, DePaul University
  Non-Presenting Author