The article by Oberlander et al1 attempts to address potential perinatal adverse effects of selective serotonin reuptake inhibitor (SSRI) use during pregnancy while accounting for depression in the mother. However, we believe that some of the conclusions they made are not supported by the data presented.
In the conclusion in the abstract, 2 statements they made were not supported by the data. They conclude that (1) “ . . . exposure was associated with an increased risk of low birth weight. . . . ” The definition of low birth weight is lower than 2500 g2 and in neither the introduction (ie, statement of purpose) nor the “Methods” section, did the authors indicate that low birth weight was an outcome that they investigated. They mention only average weight of newborns and the proportion falling lower than the 10th percentile (ie, small for gestational age). In fact, the rates of infants with weights less than the 10th percentile were 8.5%, 8.1%, and 7.4% in the 3 groups, which reveals the opposite of what the authors concluded. In the normal population, we would expect that 10% would fall at or lower than the 10th percentile (that is its definition). However, they found much lower rates, all of which are statistically significant (all P values <.05) when tested using the binomial test. Consequently, the proportions of babies who were small for gestational age were significantly lower in all 3 groups than what would be expected according to population norms. (2) “ . . . maternal illness severity was accounted for,” which was also incorrect, as they themselves stated in the “Comment” section. The complex description of propensity scores lacked validity and consequently were rather meaningless. Therefore, both of these statements are misleading, especially if an individual only reads the abstract.