The aim of the study was to investigate prospective, longitudinal associations between maternal prenatal cortisol response to an interpersonal stressor and child health for the subsequent 3 years.
One hundred twenty-three women expecting their first child provided salivary cortisol samples between 12 and 32 weeks of gestation (M (SD) = 22.4 (4.9) weeks) before and after a videotaped couple conflict discussion with their partner. Mothers reported on overall child health and several indicators of child illness (sick doctor visits, fevers, ear, and respiratory infections) when children were 6 months (n = 114), 1 (n = 116), and 3 (n = 105) years old. Associations between maternal prenatal cortisol reactivity and recovery and later child health at each of the three time points were analyzed using longitudinal regression models.
Greater cortisol reactivity in response to the couple conflict discussion was associated with maternal self-report of better overall child health (p = .016, 95% CI = 0.06–1.30, Cohen's f = 0.045) across the study period. Greater cortisol reactivity was also associated with lower incidence rate ratios for maternal reports of sick doctor visits (incidence rate ratio 95% CI = 0.25–0.83, p = .006), fevers (95% CI = 0.25–0.73, p = .002), ear infections (95% CI = 0.25–0.58, p < .001), and respiratory infections (95% CI = 0.08–1.11, p = .073). Cortisol recovery was unrelated to study outcomes (all p's > 0.05). Maternal prenatal depressive symptoms moderated the association between cortisol reactivity and overall child health (p = .034, 95% CI = 0.07–1.87 for interaction term) but no other health outcomes (p's > 0.05). Among women with lower depressive symptoms, cortisol reactivity was not associated with overall child health; among women with higher levels of depressive symptoms, greater cortisol reactivity was associated with better overall child health.
This study provides longitudinal evidence that greater maternal cortisol reactivity to a salient interpersonal stressor during pregnancy is associated with fewer child health problems and better maternal report of overall child health during infancy and into early childhood.
Trial Registration: Clinicaltrials.gov ID NCT01901536.