Changes in Defense Mechanisms in Mothers From Pregnancy to 2 Years Postpregnancy.

The objective of this study was to assess changes in maternal defensive functioning from the third trimester of pregnancy to 2 years postpregnancy. A community sample of at-risk mothers ( N = 84; non-White [61%], unmarried [67%], high school or less education [72%], and income less than $20,000 [50%]) were recruited for this longitudinal study. Mothers responded to a semistructured interview during pregnancy and at 2 years postpregnancy about the parent-infant relationship; interview transcripts were coded using the Defense Mechanism Rating Scale (DMRS). Results indicated a significant increase in both total defense mechanisms used and the relative percentage of immature defense mechanisms used over time. A significant decrease in the relative percentage of healthy/adaptive defenses was noted. When all seven levels of defenses of the DMRS were assessed, it was an increase in minor image-distorting defenses, mechanisms that supported vulnerable self-esteem, that accounted for most of the change in immature defenses. Stability coefficients of defense mechanisms were reported, with large effect sizes, for overall defensive functioning, and mature and immature defenses over a 2-year period. These findings lend support to the importance of assessing defense mechanisms to better understand stressful life transitions in mothers.