Mouse follicles grown within the eIVFG system recapitulate key events of follicle development, hormone secretion, ovulation, and luteinization. (A) Follicle growth, ovulation, and luteinization within the eIVFG system with representative bright-field follicle images on the top and histological images at the bottom. Follicles were cultured for 8 days to reach maturation; ex vivo ovulation was induced by treating mature antral follicles with 1.5 IU/ml of hCG on day 8 of eIVFG; and ovulated follicles were continuously cultured for 48 hours to allow for luteinization and progesterone secretion. Scale bar: 100 μm. (B) The cytoplasm-nucleus ratios (an indicator of luteinization) of follicular cells after 48-hour culture of ovulated follicles. (C) The concentrations of estradiol (black line) and progesterone (red line) during eIVFG and the concentrations of PGE2 across the time of ex vivo ovulation in the conditioned media. (D) Relative mRNA expression levels of established ovulatory genes examined by RT-qPCR at 0, 1, 4, and 8 hours post-hCG. N = 10–15 follicles in each group. *p < 0.05; **p < 0.01; ***p < 0.001.