OBJECTIVE: In South Asia, studies show secular trends toward slightly later women's marriage and first reproduction. However, data on related biological and social events, such as menarche and age of coresidence with husband, are often missing from these analyses. We assessed generational trends in key life events marking the transition to womanhood in rural lowland Nepal. METHODS: We used data on 110 co-resident mother-in-law (MIL) and daughter-in-law (DIL) dyads. We used paired t-tests and chi-squared tests to evaluate generational trends in women's education, and mean age at menarche, marriage, cohabitation with husband, and first reproduction of MIL and DIL dyads. We examined norms held by MILs and DILs on a daughter's life opportunities. RESULTS: On average, MIL was 29 years older than DIL (60 years vs. 31 years). Both groups experienced menarche at average age 13.8 years. MIL was married at average 12.4 years, before menarche, and cohabitated with husbands at average 14.8 years. DIL was simultaneously married and cohabitated with husbands after menarche, at average 15 years. DIL was marginally more educated than MIL but had their first child on average 0.8 years earlier (95% CI -1.4, -0.1). MIL and DIL held similar norms on daughters' education and marriage. CONCLUSION: While social norms remain similar, the meaning of "early marriage" and use of menarche in marriage decisions has changed in rural lowland Nepal. Compared to DIL, MIL who was married earlier transitioned to womanhood more gradually. However, DIL was still married young, and had an accelerated trajectory to childbearing.