Background: Previous studies reported an association between maternal psychological factors and adverse pregnancy outcomes. The objective of this study was to evaluate the relationships between maternal personality characteristics, as determined by the Minnesota Multiphasic Personality Inventory (MMPI), and infant birth outcomes and development.
Method: The inventory was administered during pregnancy to 638 pregnant women enrolled in a staff model health maintenance organization. MMPI validity as well as clinical and research scales were evaluated in relationship to infant birth outcomes (low birthweight, preterm birth) and 15-month-old infant development as assessed by the Bayley Scales of Infant Development.
Results: Mothers of low birthweight infants scored significantly lower on the hypochondriasis scale, a relationship which was no longer significant after controlling for ethnicity. No other relationships were observed between infant birth outcomes and maternal MMPI scale scores. A higher infant Mental Developmental Index (MDI) was related to higher maternal masculinity-femininity and ego-strength scale scores and lower lie and hypochondriasis scale scores. Only the relationship between infant MDI and maternal masculinity-femininity scale score remained significant after controlling for ethnicity and socioeconomic index (beta = 0.104, p = 0.036).
Conclusions: Maternal personality characteristics, as determined by the MMPI, did not appear to be significantly related to the occurrence of preterm birth or low birthweight in this healthy, general population. Maternal personality characteristics reflected in the MMPI masculinity-femininity scale appeared to be related to infant mental development, above and beyond the effects of socioeconomic status and ethnicity.