Objective: To assess in a sample of dyads admitted in mother-baby units (MBUs) whether prenatal exposure to psychotropic drugs is associated with poor neonatal outcome.
Method: We used the database collected by the French Network of Mother-Baby units (MBUs) (Société Marcé Francophone group) over 10 years (2001-2010) in 13 French psychiatric MBUs. Data about exposure to psychotropic drugs (antipsychotics, antidepressants, mood stabilizers, anxiolytics-hypnotics) and trimester of exposure (never exposed, 1st and/or 2nd trimesters, 3rd trimester) were available for 993 dyads. We considered the 3 following neonatal infant outcomes: low birth weight (< 2500g), prematurity (< 37 weeks of gestation) and neonatal hospitalization during the first month of life. Multivariate logistic regressions giving adjusted OR (aOR) were performed to explore the independent associations between prenatal exposure to the different classes of psychotropic drugs and infant outcomes, after adjustment for a priori selected confounding factors (mother’s social and demographic characteristics, pregnancy tobacco use, maternal psychiatric diagnoses (ICD-10 criteria) and type of MBUs unit (child /adult psychiatry).
Results: About half of the mothers (43.3%) used at least one psychotropic drug during pregnancy. Analyses’ exploring the impact of exposure irrespective of trimester of exposure showing an association at trend level was found between low birth weight and exposure to mood stabilizers (aOR=1.94, 95%CI=0.98-3.84, p=0.06). No association was found between exposure to psychotropic drugs and prematurity. The risk of neonatal hospitalization increased in infants prenatally exposed to anxiolytics/hypnotics (aOR=1.90, 95% CI=1.30-2.77, p=0.001) or to antipsychotics (aOR=1.84, 95% CI=1.25-2.70, p=0.002), and at trend level with antidepressants (aOR=1.49, 95% CI=0.97-2.27, p=0.06). Analyses exploring the impact of exposure according to the trimester showed that the risk for low birth weight increased significantly in infants exposed during the 3rd trimester to mood-stabilizers (aOR=2.82, 95% CI=1.34-5.96, p=0.01) or anxiolytics/hypnotics (aOR=1.59, 95% CI=0.99-2.56, p=0.05). The risk of neonatal hospitalization increased in infants exposed during 3rd trimester to antipsychotics (aOR=1.89, 95% CI=1.23-2.91, p=0.004), mood stabilizers (aOR=2.11, 95% CI=1.04-4.30, p=0.04) or anxiolytics/hypnotics (aOR=2.36, 95% CI=1.56-3.58; p=<0.0001).
Conclusion: As low birth weight is a risk factor for occurrence of a range psychiatric disorder, increasing the frequency of this risk factor in a potentially genetically vulnerable population is challenging. So, the use of mood stabilizers and anxiolytics/hypnotics during pregnancy, especially during the 3rd trimester, must be evaluated for each patient, through a detailed risk-benefit strategy. The increased risk for infant’s neonatal hospitalization, when exposed to psychotropic drugs, and again especially in the 3rd trimester, enhance the need for specialized care for women needing psychotropic treatments during pregnancy.