A longitudinal study of cognitive performance during pregnancy and new motherhood

This longitudinal study examined the popular belief that cognitive performance is impaired during pregnancy. Both self-report and objective test data on cognitive performance were collected on six occasions from three groups of women at three monthly intervals. Ten women who initially planned a pregnancy, 18 women initially in the first trimester of pregnancy, and 24 non pregnant controls completed the study. At each data collection participants reported their perceptions of current everyday memory, sleep, health, exercise, depression, anxiety and stress levels, and undertook a set of cognitive tests examining vocabulary, reasoning, short term memory, working memory, and semantic memory. A personality test was taken once. The planning group showed a significant increase in reported forgetting during pregnancy, and significantly more variability in sleep patterns than the control group over the test period. However, there were no other differences between groups on self-report or objective test results at any time phase. The personality factor of conscientiousness and level of reported anxiety were significant predictors of reported absentmindedness and forgetting on errands. The reported increase in forgetting in some pregnant women is possibly related to a complex interaction of personality and particular life situations. However, the precise nature of any objective change in memory performance during pregnancy is not yet clear.