In both cohorts, more women than men reported biological children [Cohort I: χ2 (df) = 60.49 (1), p <.0001; Cohort II: χ2 (df) = 59.58 (1), p <.0001]. Results of log-rank tests indicate significant gender and cohort differences in the cumulative probability of first childbirth. Within cohort, women reproduced earlier on average than men [Cohort I: χ2 (df) = 175.44 (1), p <.0001; Cohort II: χ2 (df) = 73.71 (1), p <.0001], with men and especially women in the older cohort reproducing earlier than men and women in the younger cohort [women: χ2 (df) = 488.08 (1), p <.0001; men: χ2 (df) = 142.80 (1), p <.0001]. Consistent with previous reports, rates of AD are higher for men than women [Cohort I: χ2 (df) = 271.00 (1), p <.0001; Cohort II: χ2 (df) = 202.46 (1), p <.0001] and in Cohort II, onset of AD occurred earlier on average for men [χ2 (df) = 204.63 (1), p <.0001].
