This pilot study aimed to evaluate the expression and distribution of granulocyte colony-stimulating factor (G-CSF), bone morphogenetic proteins 2/4 (BMP-2/4), heat shock protein 70 (HSP-70), apoptosis, progesterone, estrogen, and pentraxin-3 (PTX-3) in the endometrium of infertile women across different menstrual cycle days. This evidence concerns the gene PTX3 and Infertility.