GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE318nnn/GSE318189/primaryOK200Methylation profilingHomo sapiensMethylation profiling by genome tiling arrayhttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE318189GEOGSEfalseTrajectories of maternal epigenetic aging measures across pregnancy and postpartumPregnancy has been proposed as a biological “stress test” that may transiently accelerate maternal biological aging, followed by partial recovery in the postpartum period; however, longitudinal evidence characterizing these trajectories remains limited. This longitudinal study followed 130 women across mid to late pregnancy, early postpartum (6–9 months), and later postpartum (36–43 months) to characterize nonlinear changes in multiple markers of biological aging. Biological aging was assessed using complementary indicators, including telomere length, DNA methylation–based epigenetic aging measures, and pace-of-aging metrics. Genome-wide DNA methylation data were generated from maternal biospecimens using the Illumina Infinium MethylationEPIC v2.0 BeadChip to support derivation of epigenetic aging measures and evaluation of longitudinal methylation dynamics. Generalized additive mixed models were used to examine within-person changes over time. Results indicated relative stability or slowing of biological aging during early postpartum, followed by marker-specific patterns of stabilization or decline during later postpartum. Subsequent pregnancy during the later postpartum period was associated with shorter telomere length and altered recovery trajectories, including accelerated pace of aging among women who became pregnant again. Together, these findings suggest that while partial recovery of biological aging markers may occur following pregnancy, such recovery may be sensitive to additional reproductive demands. The DNA methylation data deposited here support longitudinal analyses of maternal biological aging across pregnancy and postpartum and provide a resource for future studies examining reproductive influences on epigenetic aging processes. Additional study data available via figshare at: https://doi.org/10.6084/m9.figshare.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 sapiens10.6084/m9.figshare.30005287