Fig. 4: Ovarian sex hormones across the menstrual cycle in those with and without long COVID.

A LC-MS/MS revealed serum 5α-dihydrotestosterone was significantly higher in those with long COVID compared to controls in the secretory phase of the cycle (p = 0.0138). B There were no differences in local endometrial tissue ovarian sex hormone concentrations measured by LC-MS/MS in women with long COVID compared to controls. C There were significantly lower PGR mRNA concentrations in proliferative endometrial tissue from women with long COVID versus controls (p = 0.0096). D Immunohistochemistry staining for AR (n = 3 representative slides shown per group at each menstrual cycle stage) revealed less intense stromal staining during the menstrual and proliferative phases and more menstrual phase glandular epithelial staining in endometrium from those with long COVID. St stroma, GE glandular epithelium, scale bar = 100 μM. E Quantification of the percentage of endometrial cells positive for AR revealed fewer positive cells in menstrual endometrium from those with long COVID vs controls (p = 0.0049). F Endometrium from those with long COVID had a significantly lower AR histoscore (number and intensity of staining) during the menstrual (p = 0.0335) and proliferative (p = <0.0001) phases. G AMH levels in those with long COVID versus controls were similar. Box and whisker plots: the box represents the upper and lower quartiles, with the horizontal line representing the median, and the whiskers represent the minimum and maximum values. Dark grey bars: long COVID, white bars: samples collected from women prior to the COVID pandemic. Statistical test: two-way ANOVA with Tukey’s multiple comparisons test, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. Letters = significance across menstrual cycle, a, b p < 0.01, c, d p < 0.05. Source data are provided as a Source Data file.