Pathik D. Wadhwa

Psychological adaptation and birth outcomes: The role of personal resources, stress, and sociocultural context in pregnancy

Prenatal psychosocial predictors of infant birth weight and length of gestation were investigated in a prospective study of 120 Hispanic and 110 White pregnant women. Hypotheses specifying that personal resources (mastery, self-esteem, optimism), prenatal stress (state and pregnancy anxiety), and sociocultural factors (income, education, ethnicity) would have different effects on birth outcomes were tested using structural equation modeling. Results confirmed that women with stronger resources had higher birth weight babies (beta = .21), whereas those reporting more stress had shorter gestations (beta = -.20). Resources were also associated with lower stress (beta = -.67), being married, being White, having higher income and education, and giving birth for the first time. There was no evidence that resources buffered the effects of stress. The importance of personal resources in pregnancy is highlighted along with implications for understanding the etiology of adverse birth outcomes.

Corticotrophin-releasing Hormone and Fetal Responses in Human Pregnancy

Abstract: During human pregnancy, maternal and fetal compartments of the human placenta produce and release corticotrophic‐releasing hormone (CRH). Elevations of placental CRH are associated with decreased gestational length (including preterm delivery). The effects of elevated placental CRH on human fetal neurological development are not known. Pregnant women in the 31st and 32nd week of gestation consented to procedures for collection of blood and measurement of fetal heart rate (FHR) in response to a series of 40 vibroacoustic stimuli (VAS). Measures of habituation and dishabituation were calculated from the FHR. All subjects were followed to delivery. Fetuses (N= 33) of women with highly elevated CRH were least responsive (p < .03) to stimulation after presentation of a novel (dishabituating) stimulus with control for parity, fetal gender, medical (antepartum) risk, and gestational length at term. In a larger sample (N= 156) a polynomial model predicted the pattern of FHR reactivity for the first 15 trials. Placental CRH concentration significantly predicted FHR reactivity after controlling for the effects of trial number, baseline FHR, inter‐trial interval, and presence of uterine contractions. Increased maternal CRH levels were significantly related to the length of gestation after controlling for the effects of fetal gender, parity, and medical risk (p= .05). The relationship between length of gestation and FHR was not significant suggesting separate actions of CRH on these events. Elevated placental CRH appears to accelerate certain developmental events (gestational length) and may influence the fetal nervous system. The impaired fetal responses to novelty and increased arousal observed in this study suggest that neurological systems may be targets for placental CRH during sensitive developmental periods.