A detailed discussion of the relationship between endometriosis and infertility is beyond the scope of this chapter and has been discussed extensively elsewhere in this text. However, a variety of mechanisms including alterations in the peritoneal environment, distorted pelvic anatomy, altered immune function, suppressed endometrial receptivity, aberrant folliculogenesis and elevated oxidative stress have been impugned as causative factors. It is thought that these factors may all combine to inhibit ovum pick-up, ovulation, oocyte quality, fertilization and/or implantation. This chapter will discuss the relative outcomes achieved with controlled ovarian hyperstimulation (COH), whether in conjunction with timed intercourse, intrauterine insemination (IUI), or in vitro fertilization in infertile patients afflicted with this disorder. 192 infertile couples for up to 3 years after laparoscopy, Akande et al noted, in contrast, that women with minimal/mild endometriosis experienced a significantly lower probability of pregnancy than women with otherwise unexplained infertility (35% vs. 55%; P<0.05). In another trial of women with a similar extent of endometriosis diagnosed laparoscopically, the 24-month cumulative pregnancy rate in 43 patients managed expectantly was 20.9% with a 16.2% probability of carrying a pregnancy beyond 20 weeks.