title: Expectant Mothers Maximizing Opportunities: Maternal Characteristics Moderate Multifactorial Prenatal Stress in the Prediction of Birth Weight in a Sample of Children Adopted at Birth.
abstract: BACKGROUND
  Mothers' stress in pregnancy is considered an environmental risk factor in child development. Multiple stressors may combine to increase risk, and maternal personal characteristics may offset the effects of stress. This study aimed to test the effect of 1) multifactorial prenatal stress, integrating objective "stressors" and subjective "distress" and 2) the moderating effects of maternal characteristics (perceived social support, self-esteem and specific personality traits) on infant birthweight.
  
  
  METHODS
  Hierarchical regression modeling was used to examine cross-sectional data on 403 birth mothers and their newborns from an adoption study.
  
  
  RESULTS
  Distress during pregnancy showed a statistically significant association with birthweight (R2 = 0.032, F(2, 398) = 6.782, p = .001). The hierarchical regression model revealed an almost two-fold increase in variance of birthweight predicted by stressors as compared with distress measures (R2Δ = 0.049, F(4, 394) = 5.339, p < .001). Further, maternal characteristics moderated this association (R2Δ = 0.031, F(4, 389) = 3.413, p = .009). Specifically, the expected benefit to birthweight as a function of higher SES was observed only for mothers with lower levels of harm-avoidance and higher levels of perceived social support. Importantly, the results were not better explained by prematurity, pregnancy complications, exposure to drugs, alcohol or environmental toxins.
  
  
  CONCLUSIONS
  The findings support multidimensional theoretical models of prenatal stress. Although both objective stressors and subjectively measured distress predict birthweight, they should be considered distinct and cumulative components of stress. This study further highlights that jointly considering risk factors and protective factors in pregnancy improves the ability to predict birthweight.
authors.affiliation: Dept of Psychiatry, University of Iowa College of Medicine, Iowa City, IA, United States of America.|Yale Child Study Center, Yale School of Medicine, New Haven, CT, United States of America.
authors.forename: Line
authors.initials: L
authors.lastname: Brotnow
authors.affiliation: Yale Child Study Center, Yale School of Medicine, New Haven, CT, United States of America.
authors.forename: David
authors.initials: D
authors.lastname: Reiss
authors.affiliation: Dept. of Mental Health Law & Policy, University of South Florida, Tampa, FL, United States of America.
authors.forename: Carla S
authors.initials: CS
authors.lastname: Stover
authors.affiliation: Dept. of Psychology, George Washington University, Washington DC, United States of America.
authors.forename: Jody
authors.initials: J
authors.lastname: Ganiban
authors.affiliation: Dept. of Counseling Psychology & Human Services, University of Oregon, Eugene, OR, United States of America.
authors.forename: Leslie D
authors.initials: LD
authors.lastname: Leve
authors.affiliation: Dept. of Psychology, Penn State University, University Park, PA, United States of America.
authors.forename: Jenae M
authors.initials: JM
authors.lastname: Neiderhiser
authors.affiliation: Dept. of Psychology, University of Pittsburgh, Pittsburgh, PA, United States of America.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Shaw
authors.affiliation: Dept of Psychiatry, University of Iowa College of Medicine, Iowa City, IA, United States of America.|Yale Child Study Center, Yale School of Medicine, New Haven, CT, United States of America.
authors.forename: Hanna E
authors.initials: HE
authors.lastname: Stevens
mesh_terms: D000300:Adoption; D001724:Birth Weight; D002648:Child; D004644:Emotions; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009035:Mothers / Q000523:psychology*; D010551:Personality; D011247:Pregnancy; D011248:Pregnancy Complications / Q000523:psychology*; D012044:Regression Analysis; D012649:Self Concept; D012944:Social Support; D013315:Stress, Psychological / Q000523:psychology*