en Original Article Original Article <strong>Background:</strong> Endometriosis is one of the most challenging diseases that constitute 20% - 40% of women searching for their infertility diagnosis. <strong>Objective:</strong> This study was undertaken in order to compare the outcome of in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) in women with endometriosis, and tubal factor infertility as controls.<br> <strong>Materials and Methods:</strong> From 2005 to 2006 a retrospective study was carried out in patients with endometriosis (n=80) and tubal infertility (n=57) after treatment with IVF/ICSI. The main outcome measures were ovarian responsiveness, quality of oocytes, implantation, pregnancy and ongoing pregnancy rates. Appropriate statistical analysis was performed using &chi;2 and student t-tests.<br> <strong>Results:</strong> No differences were found in mean number of ampoules of hMG, duration of hMG injection, number of M&Iota;&Iota; oocytes, number of embryo transferred, and rates of implantation, pregnancy, ongoing pregnancy and twin birth between women with endometriosis and tubal infertility and also between women with stages I/II or those with stages III/IV disease with women with tubal factor infertility.<br> <strong>Conclusion:</strong> Our results suggest that endometriosis does not seem to have adverse effect on outcome of IVF/ ICSI as compared with tubal infertility. Endometriosis, IVF / ICSI outcome, Tubal factor, Infertility. 1 0 http://ijrm.ir/browse.php?a_code=A-10-549-202&slc_lang=en&sid=1 Ensieh Shahrokh Tehrani Nejad tehraninejad@royaninstitute.org Yes Department of Endocrinology and Female Infertility, Reproductive Medicine Research Centre, Royan Institute, ACECR, Tehran, Iran Batool Hosein Rashidi No Department of Obstetrics and Gynecology, Tehran University of Medical Sciences, Tehran, Iran Atefeh Larti No Vali-e-asr Reproductive Health Research Centre, Tehran University of Medical Sciences, Tehran, Iran Zahra Ezabadi No Vali-e-asr Reproductive Health Research Centre, Tehran University of Medical Sciences, Tehran, Iran Nadia Jahangiri No Department of Endocrinology and Female Infertility, Reproductive Medicine Research Centre, Royan Institute, ACECR, Tehran, Iran Elham Azimi Nekoo No Vali-e-asr Reproductive Health Research Centre, Tehran University of Medical Sciences, Tehran, Iran