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Abstract Female fecundity declines in a nonlinear manner with age during the reproductive years, even as ovulatory cycles continue, which reduces female fertility, disrupts metabolic homeostasis, and eventually induces various chronic diseases. Despite this, the aging‐related cellular and molecular changes in human ovaries that occur during these reproductive years have not been elucidated. Here, single‐cell RNA sequencing (scRNA‐seq) of human ovaries is performed from different childbearing ages and reveals that the activation of the pyroptosis pathway increased with age, mainly in macrophages. The enrichment of pyroptotic macrophages leads to a switch from a tissue‐resident macrophage (TRM)‐involve immunoregulatory microenvironment in young ovaries to a pyroptotic monocyte‐derived macrophage (MDM)‐involved proinflammatory microenvironment in middle‐aged ovaries. This remolded ovarian immuno‐microenvironment further promotes stromal cell senescence and accelerated reproductive decline. This hypothesis is validated in a series of cell and animal experiments using GSDMD‐KO mice. In conclusion, the work expands the current understanding of the ovarian aging process by illustrating a pyroptotic macrophage‐involved immune mechanism, which has important implications for the development of novel strategies to delay senescence and promote reproductive health.

Abstract Abnormal resumption of meiosis and decreased oocyte quality are hallmarks of maternal aging. Transcriptional silencing makes translational control an urgent task during meiosis resumption in maternal aging. However, insights into aging‐related translational characteristics and underlying mechanisms are limited. Here, using multi‐omics analysis of oocytes, it is found that translatomics during aging is related to changes in the proteome and reveals decreased translational efficiency with aging phenotypes in mouse oocytes. Translational efficiency decrease is associated with the N6‐methyladenosine (m6A) modification of transcripts. It is further clarified that m6A reader YTHDF3 is significantly decreased in aged oocytes, inhibiting oocyte meiotic maturation. YTHDF3 intervention perturbs the translatome of oocytes and suppress the translational efficiency of aging‐associated maternal factors, such as Hells, to affect the oocyte maturation. Moreover, the translational landscape is profiled in human oocyte aging, and the similar translational changes of epigenetic modifications regulators between human and mice oocyte aging are observed. In particular, due to the translational silence of YTHDF3 in human oocytes, translation activity is not associated with m6A modification, but alternative splicing factor SRSF6. Together, the findings profile the specific translational landscapes during oocyte aging in mice and humans, and uncover non‐conservative regulators on translation control in meiosis resumption and maternal aging.