Fig. 4

Etoposide has a significant effect on follicle numbers and health on fetal, but not neonatal ovaries. a Photomicrographs of haemotoxylin and eosin stained sections from fetal (Ai-iii) and neonatal (Aiv-vi) ovaries treated with etoposide in vitro. Fetal mouse ovaries cultured for twelve days in control medium (DMSO only) (Ai); or in the presence of 50 ng ml⁻¹ (Aii); or 150 ng ml⁻¹ (Aiii) etoposide for the first six days of culture. Neonatal mouse ovaries cultured for six days with control medium (DMSO only) (Aiv); or in the presence of 50 ng ml⁻¹ (Av); or 150 ng ml⁻¹ (Avi) etoposide for the six days of culture. b, c Follicle number (b) and health (c) was determined in cultured mouse ovaries exposed to etoposide prior to (fetal ovaries: Bi, Ci) or after (neonatal ovaries: Bii, Cii) follicle formation. Figure shows: total follicle numbers (Bi, Bii); and the percentage of follicles assessed as unhealthy (Ci, Cii). Red arrows show examples of follicles deemed unhealthy due to unhealthy oocyte; yellow arrow shows examples of follicles deemed unhealthy due to unhealthy granulosa cells. Scale bars 50 μm. Bars denote mean ± SEM; n = 6 for all groups. Stars denote significant differences relative to control (*p < 0.05, **p < 0.01, ***p < 0.001)