Effects of early maternal depression on patterns of infant-mother attachment: A meta-analytic investigation

We analysed results from seven American and British studies that compared g roups of mothers with and without clinically diagnosed depression, and asse ssed the attachment category of their infants (under 3 years) using the Str ange Situation. The samples were predominantly middle-income and free of ri sk factors other than maternal depression. Metaanalysis using loglinear mod elling and standardised residuals showed that the effect of depression on t he distribution of infants' attachment was statistically heterogeneous. How ever, after removing one outlier study, the effect of depression was homoge neous across the remaining six studies. Infants of depressed mothers showed significantly reduced likelihood of secure (B) attachment and marginally r aised likelihood of avoidant (A) and disorganised (D) attachment. The first two effects varied considerably in magnitude between studies, whereas the increase in disorganised attachment, from 17 % to 28 % on average, was cons istent.