Ovarian Hyperstimulation Syndrome

Ovarian hyperstimulation syndrome represents one of the biggest nightmares of all physicians involved in ARTs. The term OHSS refers to an exacerbated response to medications used for ovarian stimulation such as clomiphene citrate and gonadotrophins. The etiology of OHSS is complex and many aspects remain unclear, but it appears that hCG whether exogenous or endogenous (e.g. pregnancy derived), is a central factor in triggering OHSS. The reported incidence of OHSS is highly variable, fortunately, the prevalence of severe forms is small with reported values ranging from 0.5 to 5%. Multiple risk factors have been implicated in the development of OHSS. Young age, low body weight, history of PCOS, and previous history of OHSS are some of these factors. OHSS also has been noted to have an increased presence of atopy. The incidence of OHSS is related to the stimulation regimen used to stimulate ovulation and parameters that are specific to IVF cycle. Pregnancy not only increases the likelihood of OHSS but prolongs the duration and severity of OHSS symptoms This article reviews the epidemiology, pathophysiology, classifications, clinical presentation and complications of OHSS. The different strategies for prevention are discussed. A stepwise approach for the management and therapeutic options also is provided with focus on the anesthetic considerations, a general approach to the evaluation and initial management of the severe and life-threatening forms of OHSS in the intensive care unit (ICU). As it is prudent for the anesthesiologist to facilitate assisted reproductive technologies (ARTs), this article, also, briefly outlines the current ARTs and the effects of anesthesia on conception.