01596nas a2200253   4500000000100000000000100001008004100002260000900043653002800052653001500080653001400095653001800109653001400127100002100141700001700162700001900179700001100198245007800209856006200287300001100349490000800360520096000368022001401328       2025                            d  c202510abranching morphogenesis10ainvolution10aLactation10aMammary gland10aorganoids1 aLaurianne Temime1 aLamia Djoual1 aAurelie Chiche1 aHan Li00aModeling Mammary Gland Development and Reproductive Cycles With Organoids  uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/boc.70048  ae700480 v1173 aMammary organoids bridge the gap between reductionist 2D systems and in vivo models by recapitulating bilayered epithelial architecture, branching, hormone responsiveness, and, in advanced platforms, functional readouts of lactation. This review synthesizes organoid models across the reproductive cycle, including branching morphogenesis, pregnancy-induced alveologenesis and milk secretion, and involution; it also surveys emerging directions, including embryonic/pluripotent and cross-species systems, as well as co-culture and organ-on-chip platforms that incorporate stromal, adipose, and immune elements. We outline priorities for building more complex, physiologically faithful ex vivo models that will enable mechanistic dissection of mammary development, yield comparative and translational insights, and create scalable platforms for perturbation and screening, advancing lactation research, breast cancer studies, and women's health in general.  a1768-322X