en Gynecology & Obstetrics Gynecology & Obstetrics Original Research Original Research <p dir="ltr" style="text-align: justify;"><strong>Background: </strong>Release of vascular endothelial growth factor (VEGF) by ovaries in response to HCG administration is one of the main mechanisms of ovarian hyper stimulation syndrome. Since Dopamine/dopamine receptor2 (Dp-r2) pathway activity -mediated by VEGF/ Vascular endothelial growth factor receptor 2 (VEGFR-2) signaling-, is associated with angiogenic events, dopamine agonists were used for the management of severe forms of OHSS. In order to assess the effects of Cabergoline on angiogenesis in the human endometrium, and subsequently its impacts on the implantation rate this study was conducted.</p> <p dir="ltr" style="text-align: justify;"><strong>&nbsp; Methods</strong>: This historical cohort study was conducted based on existing data of 115 patients (20-40 years) whom underwent assisted reproductive treatment (ART) and with a high probability for developing OHSS between March 2007 and September 2008. Forty five cases received Cabergoline were compared to 70 control subjects. The statistical methods used were: Unpaired t-test for continuous variables and the chi-square test (or Fisher&rsquo;s exact test if required) for categorical variables.</p> <p dir="ltr" style="text-align: justify;"><strong>&nbsp; Results</strong>: None of the patients (treatment or control group) developed OHSS. The etiologies of infertility and administration of GnRH agonist or antagonist protocols were similar in two groups (p>0.2). Number of transferred embryos and zygote intra-fallopian transfer (ZIFT) did not differ between the two groups (p&ge;0.06).&nbsp; Implantation rate in treatment (3.1%) and control (6.6%) subjects was similar (p=0.4). No significant difference was observed in fertilization rate, chemical, clinical and ongoing pregnancies between the two groups (p>0.5).</p> <p dir="ltr" style="text-align: justify;"><strong>&nbsp; Conclusion</strong>: Cabergoline can be safely administered in ART protocols to prevent OHSS, without compromising ART outcomes.</p> Cabergoline, Ovarian Hyper stimulation Syndrome, Dopamine agonist, OHSS, Implantation rate. 504 508 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-1003&slc_lang=en&sid=1 Shohreh Movahedi ivfshariati69@gmail.com 200319475328460023881 200319475328460023881 No Fellowship in infertility, Department of Infertility of Shariati hospital, Tehran University of Medical Sciences, Tehran, Iran. Leili Safdarian ivfshariati69@gmail.com 200319475328460023882 200319475328460023882 No Fellowship in Infertility, Department of Infertility, Tehran University of Medical Sciences, Tehran, Iran. Marzieh Agahoseini aghahoseini@sina.tums.ac.ir 200319475328460023883 200319475328460023883 No Department of Infertility of Shariati hospital, Tehran University of Medical Sciences, Tehran, Iran. Ashraf Aleyasin ivfshariati69@gmail.com 200319475328460023884 200319475328460023884 No Department of Infertility of Shariati hospital, Tehran University of Medical Sciences, Tehran, Iran. Sepideh Khodaverdi sepidehkhodaverdi@yahoo.com 200319475328460023885 200319475328460023885 Yes Endometriosis Research Center, Iran University of Medical Sciences, Tehran, Iran. Sara Asadollah . sara_asadolla@yahoo.com 200319475328460023886 200319475328460023886 No Endometriosis Research Center, Iran University of Medical Sciences, Tehran, Iran. Ali Kord Valeshabad ali_kord2006@yahoo.com 200319475328460023887 200319475328460023887 No Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA. Parvin Fallahi parvin.fallahi@yahoo.com 200319475328460023888 200319475328460023888 No Department of Infertility of Shariati hospital, Tehran University of Medical Sciences, Tehran, Iran. Zahra Rezaeeian zahra.rezaeian2000@gmaile.com 200319475328460023889 200319475328460023889 No Department of Infertility of Shariati hospital, Tehran University of Medical Sciences, Tehran, Iran.