SDC1 and cholesteryl ester measurement: Lozano et al. [72] recruited 34 infertile Spanish women with CE (information unavailable on absence and concomitance of endometriosis), which was defined as two or more CD138(+) ESPCs in 5 HPFs (4 ESPCs in 10 HPFs) and 24 infertile women without CE for a comparison of the endometrial and vaginal microbiota (V3–V4 regions) in the secretory phase.