Poster #21 - Maternal Stress During Pregnancy Predicts Child Hair Cortisol Four Years Later

• In Event: 1-169 - Poster Session 04
  In Poster Session: PS 04 Section - Biological Processes: Psychophysiology

Integrative Statement

Maternal stress during pregnancy can influence the trajectory of fetal development, shaping offspring’s physiology and health in enduring ways. Some research implicates the hypothalamic-pituitary-adrenocortical (HPA) axis as a mediator of these effects. However, it is unclear how long the effects of prenatal stress on offspring HPA output persist, and which gestational period is most susceptible to the effects of stress. The present study used hair cortisol concentration (HCC), a relatively novel method for measuring cumulative HPA output over a 3-month period, to investigate (1) if maternal stress during pregnancy predicts offspring HCC at approximately four years of age, and (2) whether effects depend on timing of maternal stress during gestation, after accounting for concurrent maternal stress.

Method:
The current study analyzed a subsample (n = 77) of mother-child dyads drawn from a larger study investigating preconception and prenatal stress in relation to birth outcomes and early child development. Maternal stress was measured with the Perceived Stress Scale (PSS; Cohen, 1998) at three time points: the second trimester of pregnancy, the third trimester, and during a follow-up laboratory visit in early childhood (Mean child age = 3.81 years, SD = .43). During this visit, children (57% female, 43% male; 64.9% Latino, 28.6% Non-Hispanic White, 6.5% African American) provided a hair sample. To obtain child HCC levels, a segment of hair 3 cm closest to the scalp was assayed, with the resulting cortisol concentration representing total cortisol output over the previous three months. A natural log transformation was used to normalize HCC’s distribution, as is standard with cortisol data. HCC was then regressed onto all three PSS scores, controlling for child’s age, sex, race, body mass index, and maternal education. Due to high multicollinearity among PSS scores, we used residualized scores that parsed out variance associated with the other two PSS scores and entered these simultaneously in a multiple linear regression to isolate the unique contribution of each period.

Results:
Regression analyses revealed that higher maternal perceived stress during the third trimester was significantly associated with greater child HCC (β = .67, SE = .32, p = .04). Child HCC was not significantly predicted by second trimester maternal perceived stress (β = .10, p = .64) or concurrent maternal perceived stress (β = .32, p = .24).

Discussion:
These results suggest the possibility that maternal stress in late pregnancy may have enduring effects on child HPA output that persist up to four years after birth. The finding that third-trimester prenatal stress predicted HCC more strongly compared to second trimester and concurrent maternal stress suggests that this gestational period might be particularly sensitive to prenatal programming of the HPA axis. This finding is consistent with animal models showing that stress exposure downregulates 11β-hydroxysteroid dehydrogenase type 2, a placental enzyme that partially protects the fetus from elevated maternal cortisol levels (Sandman et al., 2012), which may be particularly problematic later in gestation as cortisol levels rise progressively across pregnancy (Buss et al., 2012).

Authors

• Nicholas Alen, University of California, Davis
  Presenting Author

• Camelia E. Hostinar, University of California-Davis
  Non-Presenting Author

• Christine M. Guardino, Dickinson College
  Non-Presenting Author

• Nicole E. Mahrer, UCLA
  Non-Presenting Author

• Madeleine U. Shalowitz, NorthShore University Health System Research Institute
  Non-Presenting Author

• Sharon L. Ramey, Virginia Tech
  Non-Presenting Author

• Christine Dunkel Schetter, UCLA
  Non-Presenting Author