One study that assessed mRNA expression for various vitamin D‐related factors including VDR, CYP27B1 and the catabolic enzyme 24‐hydroxylase (CYP24A1) in ovarian tissues showed that women with endometriosis had higher expression of VDR, CYP27B1 and CYP24A1 [49]. This evidence concerns the gene VDR and endometriosis.