Forty-four children who had been born preterm and their mothers participated in the follow-up study. At 3 and 14 months (corrected age) cognitive development was assessed using the BOS 2-30, the Dutch version of the Bayley Scales of Infant Development. The BOS yields measures of mental and motor development. At 7.5 years, intelligence was measured using the WISC-RN, the Dutch version of the WISC-R. A composite measure of maternal rigidity, tapping rigidity as a personality trait and rigid attitudes to child-rearing was used. The results of a multiple regression analysis indicated that maternal rigidity, measured in the first year of the child's life, was not associated with mental performance at 3 or 14 months. At 7.5. years, however, it was strongly associated with cognitive development, contributing uniquely to performance IQ.