Right amygdala | Left amygdala | Right hippocampus | Left hippocampus | |

Model 1: Maternal cortisol in midgestation (AUC1) | ||||

Girls | 0.008 ± 0.04 | 0.02 ± 0.03 | −0.03 ± 0.08 | 0.02 ± 0.07 |

P value | 0.83 | 0.48 | 0.70 | 0.78 |

Boys | −0.009 ± 0.02 | 0 ± 0.02 | 0 ± 0.05 | 0.02 ± 0.05 |

P value | 0.67 | 0.89 | 0.92 | 0.68 |

Model 2: Maternal cortisol in late gestation (AUC2) | ||||

Girls | 0 ± 0.03 | 0 ± 0.03 | 0.01 ± 0.09 | 0.01 ± 0.09 |

P value | 0.99 | 0.91 | 0.83 | 0.89 |

Boys | −0.014 ± 0.04 | 0 ± 0.04 | −0.07 ± 0.13 | −0.04 ± 0.12 |

P value | 0.73 | 0.99 | 0.59 | 0.76 |

Values presented as β ± SEM. Sex-specific associations between maternal cortisol concentrations and child brain volumes were assessed by including an interaction term between maternal cortisol in pregnancy and sex of the child. All regression analyses were adjusted for obstetric risk, length of gestation, birth weight percentile, child age, sex, handedness, and maternal depression at child follow-up. The following regression model was applied. Child brain volume = β

_{0}+ β_{1}* maternal cortisol^{1}+ β_{2}* sex + β_{12}* (maternal cortisol^{1}* sex) + β_{3}* obstetric risk + β_{4}* birth weight percentiles + β_{5}* length of gestation + β_{6}* maternal depression at child assessment + β_{7}* child age at MRI assessment + β_{8}* child handedness” + β_{9}* maternal cortisol earlier in gestation^{2}. (^{1}AUC_{1}in model 1 and AUC_{2}in model 2;^{2}Maternal cortisol concentrations at 15 wk gestation in model 1 and AUC_{1}in model 2.) Note that, by setting sex = 0 for girls, the estimate of β_{1}provides the expected change in brain volume corresponding to one unit increase in maternal cortisol among girls. By setting sex = 1 for boys, the estimate of β_{1}+ β_{12}provides the expected change in brain volume corresponding to one unit increase in maternal cortisol among boys.