Symposium
Chair: Tiffany Field
Discussant: Janet A. DiúPietro
This symposium will present data showing the prenatal depressioneffects on the fetus and the newborn. In the first paper, the newbornsof prenatally depressed mothers are assessed in three differentperceptual discrimination studies. In these studies the newborn of theprenatally depressed mother is shown to spend less time exploringdifferent texture objects by mouth and by hand. In the other studiesthe newborns of depressed mothers were slower to habituate. In a second set of studies, newborns of prenatally depressed motherswere shown to have greater relative right frontal EEG activation andlower vagal tone. Because of the less optimal performance on theperceptual discrimination tasks and the depressed-appearing EEG patternand lower vagal tone in these newborns, we conducted a study during theprenatal period assessing the mothers' neurotransmitter and stresshormone levels and fetal activity during ultrasound assessments. Inthis study the depressed mothers showed higher urinary catecholamine andstress hormone levels which were later mimicked by their newborns'catecholamine and stress hormone levels. The ultrasound examinationsrevealed greater fetal activity in the newborns of the depressed mothersand they were noted to show less optimal performance on the Brazelton. These studies combined suggest that the mothers' prenatal catecholaminesand stress hormone levels may have affected fetal activity andultimately the newborn's postnatal catecholamines and stress hormones aswell as the newborn's physiology and behavior. The final presentationsuggests that this may happen both by maternal cortisol crossing theplacenta as well as stress hormone levels generated by the fetusitself. The papers combined highlight the importance of furtherprenatal depression effects research and the need for prenatalintervention.
Details of individual items:
paper
Studies conducted over the past 30 years reveal that shortly after birth, infants are remarkably perceptive of objects and events in their surroundings. Another growing body of research reveals that infants of depressed mothers are at risk for developmental delays. The present series of studies examined the perceptual skills of newborns of depressed versus non-depressed mothers in an effort to study maternal depression effects on infants' perceptual development. All of the studies employed counterbalancing of stimuli across infants and included reliability measures and precautions against experimenter bias. The groups of infants did not differ on background demographic information (i.e., obstetrics complications, maternal age, infant age, etc). Three studies examined infants' mouthing or handling of objects placed in their hands and one examined face perception. In one study, twenty-four newborns (M age 12 days) of depressed (n12) and non-depressed mothers were presented with alternating trials of a smooth or nubby textured fingertip to mouth. Both groups of newborns showed a preference to suck the smooth, perhaps more familiar texture, suggesting they discriminated the different stimuli. However, the newborns of the depressed mothers spent half as much time orally exploring stimuli, one-third less time orally exploring the more novel nubby texture and 59% less time mouthing the smooth texture. That newborns of depressed mothers suck less may reflect biological differences. Less exploration has also been correlated with developmental delays. In a second study using an habituation/ dishabituation paradigm, forty newborns (M age 27 hours old) of depressed (n ) and non-depressed mothers were assessed for haptic perception of a cold versus a warm temperature tube. Infants of depressed mothers required more time to habituate and showed passive haptic exploratory behaviors (e.g., light holding of object) compared with infants of non-depressed mothers who displayed active exploration of the temperature tubes (e.g., opening and closing the hand, trying to mouth the object). Regression analyses revealed that 36% of the variance for exploratory style (active versus passive) could be accounted for by maternal depression. Using the same paradigm, passive haptic exploration was also evident when newborns (M age 44.5 hours old) of depressed (n22) mothers were presented with vials of varying weights. Preliminary findings on a fourth study with fourteen newborns (M age 36 hours) reveals that infants of depressed (n10) mothers require more trials and twice as much time to habituate to their mothers' face when compared with infants of non-depressed mothers (n10). In summary, these findings reveal that infants of depressed mothers are slower to habituate, require more time to detect objects and faces, and are less engaged or active in exploring their environment. These may be precursors of perceptual developmental delays. Future research is needed to understand the underlying basis for these differences.
paper
Recent studies have demonstrated that newborns of depressed mothershave a behavioral profile of dysregulation that is characterized by: 1)limited responsiveness on the Brazelton; 2) decreased responsivenessduring affective stimuli; and 3) more indeterminant sleep. The purposeof the present study was to assess the physiological profile ofdysregulation that may be present in these newborns. Across the three studies presented, maternal depression was assessedusing the CES-D (> 16 for depressed mothers and <12 for non-depressedmothers) and DIS interview (depressed mothers met criteria fordysthymia, major depressive disorder or both). EEG and EKG patternswere examined for newborns of depressed (n 68) and non-depressed (n 60) mothers. Multivariate analyses of variance yielded significantgroup differences suggesting that the newborns of depressed mothersshowed greater relative right frontal EEG asymmetry (due to left frontalhypoactivation). Chi square analyses revealed differences between thenumber of newborns of depressed mothers who showed negative asymmetryscores versus the number of newborns of non-depressed mothers who showedthis pattern. Newborns of depressed mothers also showed lower vagaltone compared to newborns of non-depressed mothers, suggesting lessphysiological maturity. These physiological data highlight the broad impact that maternaldepression has on neonatal function. Although questions concerning theorigins of the EEG, EKG and vagal tone levels in newborns remainunanswered, these data provide corroborating evidence that slower andpossibly more dysregulated maturation may occur in newborns of depressedmothers. Combined behavioral and physiological patterns and thecompounding effects of later disorganized maternal interaction patternsmake these newborns more prone to risk factors associated with lateraffective disorders and suggest the need for prenatal intervention.
paper
To examine the effects of maternal depression on fetal activity andneonatal stress hormones, depressed pregnant mothers and their fetuseswere examined during pregnancy and again after delivery. The depressedmothers showed higher urinary cortisol and lower urinary dopamine andserotonin levels than the non-depressed mothers did during pregnancy. During the neonatal period, the newborns of depressed mothers showedelevated urinary cortisol levels and lower dopamine and serotonin levelsthan the neonates of non-depressed mothers, thereby, mimicking thebiochemical patterns displayed by their mothers during pregnancy. Ultrasound examinations revealed that the fetuses of depressed motherswere significantly more active than the fetuses of non-depressed mothersacross the second and third trimesters of pregnancy. The newborns ofdepressed mothers also showed less optimal scores on the Brazeltonneonatal behavioral assessment habituation, orientation, range of state,autonomic stability and depression clusters. Significant correlations suggested the following relationships: 1)greater maternal depression during pregnancy was related to higherprenatal cortisol and norepinephrine levels and lower dopamine levels;2) the mothers' dopamine and serotonin levels were related; and 3)greater fetal activity was related to lower prenatal serotonin levelsand elevated cortisol levels. These results support previous findings showing that infants ofdepressed mothers have specific behavioral and biochemical profilessimilar to their mothers as early as the newborn period. In addition,these findings suggest that depressed mothers' distinct physiologicaland biochemical profiles may affect the fetus and thereby its physicaland mental development.
paper
Fetuses from twenty weeks gestation showed an increase in plasmacortisol, beta-endorphin, and noradrenaline levels in response toneedling of the fetal body during blood transfusion. The degree ofresponse was independent of gestational age. The mothers showed noincrease in plasma levels of cortisol or beta-endorphin hormones aftertransfusion, but a significant increase of noradrenaline. This mayreflect a pregnancy-induced desensitization of the HPA axis. The lackof maternal response and cortisol and beta-endorphin levels confirmsthat the changes in fetal levels were generated by the fetus itself. Maternal-fetal ratios were 11 for cortisol, 0.5 for beta-endorphin and10.5 for noradrenaline. Paired baseline levels of maternal and fetalhormone levels showed a highly significant correlation for cortisol (r 0.6, p< .001), but none for beta-endorphin or noradrenaline. Thissuggests that whereas no significant beta-endorphin or noradrenalinecrosses the placenta, enough maternal cortisol may do so to have afunctional effect on the fetus. This may be a method by which antenatalmaternal stress has a long term effect on the set of the HPA axis of theoffspring.