Diego, Miguel Angel

EEG was examined in 348 1-week, 1-month and 3-month-old infants of depressed and non-depressed mothers. Both the percentage of infants exhibiting spectral peaks and the frequency in Hz at which those peaks were exhibited increased with age. Similarly, the EEG spectra showed a developmental increase in absolute power and a decrease in lower frequency and increase in higher frequency components. Infants of depressed mothers exhibited greater 8Hz lower 3Hz relative power and greater left frontal EEG log-absolute power than infants of non-depressed mothers. This profile was specially marked across a narrow frequency range which shifted from 3--9Hz to 4--9Hz by 3-months. Evaluation of 4 different asymmetry indices revealed that while both the log-absolute difference and the absolute ratio asymmetry indices best differentiated infants of depressed from infants of non-depressed mothers, the absolute ratio asymmetry index appeared to minimize within group variability. The significance of these findings are discussed.

Maternal neuroendocrine function during pregnancy has been related to a number of pregnancy outcomes including less optimal fetal growth patterns. Animal models have consistently demonstrated that glucocorticoid infusions to the mother result in fetal growth restriction and norepinephrine infusions in reduced blood flow to the fetus. Similarly, human studies reveal that elevated maternal HPA axis and adrenal function (associated with stress anxiety and depression) during pregnancy is related to prematurity and low birthweight. The present study examined the relationship between maternal cortisol and norepinephrine and fetal growth measures during mid-gestation. Correlation analyses revealed that both maternal psychological (daily hassles, depression and anxiety) and biochemical (cortisol and norepinephrine) variables were negatively related to fetal growth measures. Hierarchical multiple regression analyses further revealed that maternal cortisol was the best single maternal predictor of fetal growth accounting for a significant portion of the variance even after controlling for gestational age and fetal gender. Results from the structural equation model indicate that the effects of maternal psychological distress on fetal growth are mediated by maternal cortisol. Potential mechanisms of action are discussed.