Background Infertility is defined as failure to conceive after 1 year of regular, unprotected intercourse. It has been estimated that 10% to 15% of couples are infertile, with 35% of cases due to female factors and 20% due to male and female factors combined. Although implantation of the fertilized egg is a key step in reproduction, the exact mechanism of embryonic implantation is not completely understood. The endometrium, or uterine lining, undergoes cyclic changes, and the implantation window occurs between days 20 and 24 of the menstrual cycle. During the implantation window, three proteins, known as integrins, appear in the endometrium and participate in the cell adhesion process. An absence of these integrins has been noted in cases of endometriosis, fallopian tube blockage, and unexplained infertility. Of the three integrins, the alpha v beta 3 (avß3) molecule is the best characterized and its distribution on the embryo and endometrium places it in a strategic location for a direct role in embryonic attachment. Therefore, avß3 integrin has been investigated as a potential marker of uterine receptivity and a participant in implantation.