The purpose of this study was to describe the differences between primigravidae and multigravidae women in their experience of sleep efficiency, fatigue and vitality, and level of functioning in the third trimester of pregnancy and the first month postpartum. A secondary analysis of a descriptive, longitudinal study was done. A convenience sample of 31 pregnant women was used to test the hypothesis that multigravidae would have significantly higher levels of functioning in the household, increased fatigue, and decreased sleep efficiency and vitality than primigravidae at both phases of the study. Results indicate, however, that primigravidae experienced significantly more disturbed sleep, with sleep efficiency falling from 89.79% in the third trimester to 77.25% postpartum. Multigravidae had only a minor reduction in sleep efficiency from 86.76% in the third trimester to 83.99% postpartum. Although there was no statistically significant difference in level of vitality, primigravidae experienced more fatigue (73.58 +/- 15.22) than multigravidae (64.35 +/- 18.96) at 1 month postpartum. These results suggest that maternal role ''acquisition,'' experienced by primigravidae, results in more fatigue and sleep disruption than does maternal role ''expansion.'' The significant decrease in sleep efficiency and increase in fatigue in primigravidae after delivery indicate that health care professionals need to provide anticipatory guidance to primigravidae to help smooth the transition from pregnancy to motherhood.