Disaster-related prenatal maternal stress predicts HPA reactivity and psychopathology in adolescent offspring: Project Ice Storm.

BACKGROUND: Prenatal stress has been associated with adverse outcomes in offspring, including elevated risk of psychopathology. Fetal programming of the hypothalamic-pituitary-adrenal (HPA) axis has been posited as a biological mechanism underlying such consequences. The present study aimed to examine whether dysregulation of the offspring HPA axis mediates the relationship between prenatal stress exposure and adolescent psychopathology. METHODS: Five months after the Quebec ice storm of 1998, women who had been pregnant at the time of the storm completed questionnaires about their objective hardship and subjective distress from the disaster. A total of 45 of their children, exposed to the ice storm in utero, participated at 13 years of age. Adolescents completed the Trier Social Stress Test while providing salivary samples to measure circulating cortisol levels. Maternal report of adolescent behaviors was assessed with the Child Behavior Checklist. RESULTS: Results from the study found that greater objective hardship was associated with elevated offspring cortisol reactivity at 13 years of age. Furthermore, greater subjective distress was associated with greater externalizing behaviors. While lower cortisol reactivity predicted greater externalizing behaviors, it did not mediate the association between maternal objective hardship or subjective distress and offspring externalizing or internalizing behaviors. CONCLUSIONS: Findings suggest that objective hardship in pregnancy has long-term implications for offspring HPA axis functioning, which is also associated with externalizing behaviors. While dysregulation of the offspring HPA axis did not mediate the association between prenatal stress and offspring psychopathological symptoms, further research is warranted to investigate programming of alternative biological systems.

QF2011: a protocol to study the effects of the Queensland flood on pregnant women, their pregnancies, and their children's early development.

BACKGROUND: Retrospective studies suggest that maternal exposure to a severe stressor during pregnancy increases the fetus' risk for a variety of disorders in adulthood. Animal studies testing the fetal programming hypothesis find that maternal glucocorticoids pass through the placenta and alter fetal brain development, particularly the hypothalamic-pituitary-adrenal axis. However, there are no prospective studies of pregnant women exposed to a sudden-onset independent stressor that elucidate the biopsychosocial mechanisms responsible for the wide variety of consequences of prenatal stress seen in human offspring. The aim of the QF2011 Queensland Flood Study is to fill this gap, and to test the buffering effects of Midwifery Group Practice, a form of continuity of maternity care. METHODS/DESIGN: In January 2011 Queensland, Australia had its worst flooding in 30 years. Simultaneously, researchers in Brisbane were collecting psychosocial data on pregnant women for a randomized control trial (the M@NGO Trial) comparing Midwifery Group Practice to standard care. We invited these and other pregnant women to participate in a prospective, longitudinal study of the effects of prenatal maternal stress from the floods on maternal, perinatal and early childhood outcomes. Data collection included assessment of objective hardship and subjective distress from the floods at recruitment and again 12 months post-flood. Biological samples included maternal bloods at 36 weeks pregnancy, umbilical cord, cord blood, and placental tissues at birth. Questionnaires assessing maternal and child outcomes were sent to women at 6 weeks and 6 months postpartum. The protocol includes assessments at 16 months, 2½ and 4 years. Outcomes include maternal psychopathology, and the child's cognitive, behavioral, motor and physical development. Additional biological samples include maternal and child DNA, as well as child testosterone, diurnal and reactive cortisol. DISCUSSION: This prenatal stress study is the first of its kind, and will fill important gaps in the literature. Analyses will determine the extent to which flood exposure influences the maternal biological stress response which may then affect the maternal-placental-fetal axis at the biological, biochemical, and molecular levels, altering fetal development and influencing outcomes in the offspring. The role of Midwifery Group Practice in moderating effects of maternal stress will be tested.

Prenatal maternal stress predicts stress reactivity at 2½ years of age: the Iowa Flood Study.

Prenatal maternal stress (PNMS) predicts psychosocial development in offspring. It has been hypothesized that during PNMS, glucocorticoids pass the placenta, reaching the foetus, leading to a long-term reprogramming and dysregulation of the foetal hypothalamic-pituitary-adrenal (HPA) axis. However, results are inconsistent across PNMS studies. One problem may be the confounding of objective degrees of hardship due to the stressor and subjective degrees of distress in the mother. The present study investigated the association between objective and subjective PNMS due to a natural disaster, the June 2008 Iowa floods, and stress reactivity in the offspring at 2½ years of age. Women who were pregnant during the floods were recruited, on average, within three months of the floods and their stress levels assessed. Mothers and their toddlers (n = 94 dyads) participated in a brief mother-toddler separation to induce physiological stress responses in the offspring. Salivary cortisol samples were collected four times during the procedure. We computed absolute change in cortisol (baseline to 20-minute post-stressor; baseline to 45-minute post-stressor) and Area Under the Curve with respect to increase and ground (AUCi; AUCg). Objective and subjective PNMS were positively correlated with AUCi, as was timing in gestation: the later in pregnancy the exposure occurred, the greater the cortisol increase. Controlling for objective hardship and other covariates, sex-by-subjective PNMS interactions showed a significant and positive association between subjective PNMS and Absolute Increase (45 min) and AUCi in females only, with little effect in males. These results suggest that PNMS leads to long-term alterations in the functioning of the HPA axis, evident as early as 30-months of age.

Oxytocin in pregnancy and the postpartum: relations to labor and its management.

The purpose of this study was to examine variations in endogenous oxytocin levels in pregnancy and postpartum state. We also explored the associations between delivery variables and oxytocin levels. A final sample of 272 mothers in their first trimester of pregnancy was included for the study. Blood samples were drawn during the first trimester and third trimester of pregnancy and at 8 weeks postpartum. Socio-demographic data were collected at each time point and medical files were consulted for delivery details. In most women, levels of circulating oxytocin increased from the first to third trimester of pregnancy followed by a decrease in the postpartum period. Oxytocin levels varied considerably between individuals, ranging from 50 pg/mL to over 2000 pg/mL. Parity was the main predictor of oxytocin levels in the third trimester of pregnancy and of oxytocin level changes from the first to the third trimester of pregnancy. Oxytocin levels in the third trimester of pregnancy predicted a self-reported negative labor experience and increased the chances of having an epidural. Intrapartum exogenous oxytocin was positively associated with levels of oxytocin during the postpartum period. Our exploratory results suggest that circulating oxytocin levels during the third trimester of pregnancy may predict the type of labor a woman will experience. More importantly, the quantity of intrapartum exogenous oxytocin administered during labor predicted plasma oxytocin levels 2 months postpartum, suggesting a possible long-term effect of this routine intervention, the consequences of which are largely unknown.