['Earlier general population studies have shown that novelty seeking (NS) of the Temperament and Character Inventory (TCI) of personality is lower for persons born in winter compared to those born in summer, particularly for women. Here, we investigate if this result can be replicated in another population.', 'The Northern Finland 1966 Birth Cohort, comprising 4968 subjects (2725 women, 2243 men), was investigated with regard to the temperament dimensions of the TCI and the season of birth.', 'Novelty seeking and reward dependence (RD) showed significant variations according to the month of birth. We found that women born during winter have significantly lower levels of NS compared to women born during summer, with a minimum for the birth month November and maximum for May. These results are similar to those found in a previous Swedish study. Furthermore, our study showed that men born during spring had significantly lower mean scores of RD compared to men born during autumn, with a minimum for birth month March. This was in contrast to the Swedish study, where the minimum of RD was obtained for the birth month December.'] Is novelty seeking among adult women lower for the winter borns compared to the summer borns : replication in a large Finnish birth cohort?