Figure 2.

Apoptosis precedes menstrual shedding in the human endometrium. Expression of cleaved caspase-3 was analysed by immunohistochemistry and semi-quantitative histoscoring. (a) Representative photomicrographs of endometrial tissue sections at high power and low power with isotype control insets. GE = glandular epithelium, St = stroma. (b) Cleaved caspase-3 (CC3) expression in the endometrial glands and stroma plotted against day of patient menstrual cycle. Each x-value represents data from one individual patient sample, therefore some cycle days are repeated. Dark grey box indicates the period of menstruation. (c, d) CC3 expression in endometrial glands and stroma grouped by menstrual cycle phase. Results are presented as mean ± SEM, with results consistent across three technical replicates. Significance determined by 1-way ANOVA and Tukey’s multiple comparisons test. *p < 0.05, **p < 0.01.