Epidemiology and prevention of ovarian hyperstimulation syndrome (OHSS): a review

Abstract

Ovarian hyperstimulation syndrome (OHSS) is a rare iatrogenic complication of ovarian stimulation occurring during the luteal phase or during early pregnancy. Fortunately, the reported prevalence of the severe form of OHSS is small, ranging from 0.5 to 5%. Nevertheless, as this is an iatrogenic complication of a non-vital treatment with a potentially fatal outcome, the syndrome remains a serious problem for specialists dealing with infertility. The aim of this literature review was to determine whether it is possible to identify patients at risk, and which preventive method should be applied when an exaggerated ovarian response occurs. Data pertaining to the epidemiology and prevention of OHSS in women were searched using Medline, Current Contents and PubMed, and are summarized. Preventive strategies attempt either to limit the dose or concentration of hCG or to find a way to induce luteolysis without inducing a detrimental effect on endometrial and oocyte quality. The following particular preventive strategies were reviewed: cancelling the cycle; coasting; early unilateral ovarian follicular aspiration (EUFA); modifying the methods of ovulation triggering; administration of glucocorticoids, macromolecules and progesterone; cryopreservation of all embryos; and electrocautery or laser vaporization of one or both ovaries.

Do estrogen receptor alpha polymorphisms have any impact on the outcome in an ART program?

“…Furthermore, certain predictive models of ovarian response have been developed, but they have modest accuracy and limited clinical use, because of high intra-and inter-individual variability [8] . As a result, the optimal gonadotropin starting dose has not been established and it is chosen empirically, based on clinical judgment and experience, while the response may vary and sometimes results either in hypo-response and cycle cancellation or hyper-response and the potentially life-threatening complication of ovarian hyperstimulation syndrome [6,13].…”

Application of GnRH antagonist in combination with clomiphene citrate and hMG for patients with exaggerated ovarian response in previous IVF/ICSI cycles

“…The risk factors associated with OHSS are younger age, asthenic habitus, rapidly increasing estradiol (E2) levels, high preovulatory serum E2 levels, large number of follicles during ovarian stimulation, polycystic ovary syndrome (PCOS), and the presence of ultrasounddetected polycystic ovaries [1][2][3]. Moreover, after the introduction of gonadotropin-releasing hormone agonist (GnRHa), a sixfold increase in the incidence of severe OHSS has been observed relative to the clomiphene citrate (CC)/human menopausal gonadotropin (hMG) protocol [3].…”

“…Among those, coasting appears to be the most frequently used for the prevention of OHSS [5]. This approach is based on the assumption that serum E2 levels on the day of hCG injection are predictive of the risk of OHSS [3]. Coasting involves cessation of exogenous gonadotropin stimulation when serum E2 and the number and size of growing follicles reach a certain threshold.…”

“…Coasting involves cessation of exogenous gonadotropin stimulation when serum E2 and the number and size of growing follicles reach a certain threshold. GnRHa is maintained and the administration of hCG is postponed until serum E2 levels decrease to a safer range [3,6]. Although coasting results in satisfactory pregnancy rate (36.5-63%) and low incidence of severe OHSS (<2%) [6], it increases patients' inconvenience and cost.…”

“…Some women, however, develop excessive ovarian response or even OHSS despite coasting. Since GnRHa suppression confers a risk for OHSS [2,3] and patients who have a history of excessive ovarian response or OHSS are prone to develop it again in subsequent cycles [2,4], some modification of the stimulation protocol must be made in next cycle.…”