AACAP: Not Treating Depression During Pregnancy Affects Baby

SAN DIEGO, Calif., Oct. 26 -- Although antidepressants may have an effect on fetuses in utero, so may the lack of the drug during pregnancy.

Babies born to women with untreated major depressive disorder had significant changes in neurobehavioral function, were born at an earlier gestational age, and had elevated stress hormones, according to a small study reported at the American Academy of Child and Adolescent Psychiatry meeting here.

"The question is, does bathing an infant in an intrauterine environment where the mother's stress hormones are high affect the baby?" said Sheila M. Marcus, M.D., of the University of Michigan in Ann Arbor.

While some evidence has suggested that the medications used to treat depression, such as selective serotonin reuptake inhibitors (SSRIs), may have a negative prenatal impact, the issue is still unclear and little study has been done on the effect of untreated depression during pregnancy, Dr. Marcus and and colleagues said.

The investigators reported the preliminary findings from 53 infant-mother pairs of 135 pregnant women enrolled in the study. Maternal plasma cortisol and other stress hormones were measured throughout pregnancy. Infant cord blood was examined for adrenocorticotrophic hormone and cortisol while salivary cortisol was measured for the first seven months after birth.

The study by Dr. Marcus and colleagues found that infants born to women with depression were born significantly earlier. Mean gestational ages were:

• 35.6 weeks for infants born to women with major depressive disorder.
• 38.6 weeks for those of women with high risk of depression (past history of depression or Edinburgh Postnatal Depression Scale likelihood ratio greater than 10).
• 39.4 weeks for those born to women at low risk of depression (no past history of depression and Edinburgh Postnatal Depression Scale likelihood ratio less than 10).

Motor maturity tended to be lower and cortisol levels higher in the infants with depressed mothers, but the differences were not significant.

Regarding the limbic-hypothalamic-pituitary-adrenal axis (LHPA), women who developed major depressive disorder had significantly higher cortisol and adrenocorticotropic hormone levels compared to low risk women (P=0.05). Cord blood of babies born to depressed mothers tended to have more cortisol, but the trend did not reach significance in the relatively small group analyzed.

No significant differences were seen when the babies were scored at age two weeks on a neurobehavioral scale that describes developmental and behavioral maturation, central nervous system integrity and stress responses.

The findings for infants of high risk women were:

• Poorer quality of movement (-0.36 versus -0.26 low risk, P=0.07),
• More hypotonia (0.49 versus -0.22 low risk, P>0.01), and
• Higher stress scores (0.56 versus 0.13 low risk, P>0.003).

"These findings may indicate altered neurological development," Dr. Marcus and colleagues said.

The researchers cautioned that the findings are preliminary but said the study "may improve our understanding of the early genesis of mood disorders."