From breakdown to repair: A human organoid model of menstruation.

Menstruation entails repeated cycles of cyclical shedding and scarless regeneration of the endometrium, yet the precise cellular states underlying this process have remained poorly defined. In this issue, Nikolakopoulou et al. establish an in vitro menstrual cycle (IVMC) protocol using human endometrial organoids, revealing WNT7A as a central regulator of epithelial regeneration.