Severe ovarian hyperstimulation syndrome: Can we eliminate it through a multipronged approach?

Ovarian Hyperstimulation Syndrome (OHSS) requiring Intensive Care Unit (ICU) admission between 1996-2020 in England, Wales, and Northern Ireland

INTRODUCTION

Ovarian Hyperstimulation Syndrome (OHSS) is a life-threatening iatrogenic complication of In vitro fertilisation (IVF). This study aimed to quantify rates of Ovarian Hyperstimulation Syndrome (OHSS) requiring intensive care unit (ICU) admission and assess whether trends have changed between 1996-2020 commensurate with the introduction of safer IVF practices.

METHODS

Data regarding Intensive Care Unit (ICU) admission across England, Wales and Northern Ireland was gathered retrospectively from the Intensive Care National Audit and Research Centre (ICNARC) database. 38,957 female patients aged between 18-55 years were admitted to ICU for OHSS or related conditions between 1996-2020. The primary outcome was the rate of OHSS requiring ICU admission expressed as a proportion of the number of fresh IVF cycles conducted in that year according to Human Fertility and Embryology Authority (HFEA) records. Baseline characteristics (for example, age, ethnicity, BMI), biochemical parameters (such as renal function, serum electrolytes), length of ICU stay and duration and need for organ support, were also compared between ICU patients with 'confirmed OHSS' and those 'without OHSS'.

RESULTS

There were 238 cases of 'confirmed OHSS' requiring ICU admission recorded between 1996-2020. Rates of OHSS requiring ICU admission declined over the study period (P=0.006); the annual rate of severe OHSS requiring intensive care admission halved when comparing those occurring between 1996-2007 and 2008-2020 (OR=0.37, 95% CI 0.37-0.45; P<0.0001). Patients spent a mean of 3.5 days in the ICU, with 86.3% of patients with 'confirmed OHSS' requiring at least 2 days of higher level (i.e., level 2 or 3) care. Patients with 'confirmed OHSS' required a shorter duration of renal, advanced cardiovascular, and advanced respiratory support than patients 'without OHSS' (P<0.0001 for all comparisons). There was no significant difference in BMI or ethnicity between those with 'confirmed OHSS' and those 'without OHSS', however women with 'confirmed OHSS' were younger (34 versus 41 years old, p<0.0001).

DISCUSSION

Although absolute rates of OHSS requiring ICU admission recorded in this study are likely to represent a significant underestimate of all clinically significant OHSS, rates of OHSS requiring ICU admission have decreased since 1996 in concordance with the introduction of modern IVF practices.

Alternative strategies for the management of ovarian hyperstimulation syndrome, the role of intra-abdominal hypertension control

The aim of this study is to analyze the methods for reducing intra-abdominal pressure (IAP) in the management of the moderate and severe forms of ovarian hyperstimulation syndrome (OHSS). We carried out a systematic review of the literature. An evaluation of clinical trials, meta-analysis, case-reports, and reviews assessing the management of conditions associated with OHSS and intra-abdominal hypertension (IAH)/abdominal compartment syndrome (ACS) was made using the following data sources: MEDLINE Pubmed (from 1966 to July 2019) and the Cochrane Controlled Clinical Trials Register, Embase (up to July 2019). The principles of treatment of IAH syndrome can be considered in the treatment of moderate and severe forms of OHSS. Medical treatment of patients with increased IAP in OHSS should be started early to prevent further organ dysfunction and avoid a transition to a more severe stage of IAH and ACS. Some of the new, non-surgical methods, such as continuous negative extra-abdominal pressure, are a promising option in specific groups of patients with OHSS. This review provides suggestions for the management of OHSS based on the principles of therapy for IAH syndrome. Further well-designed studies are needed to confirm these initial data.

Early onset of cabergoline therapy for prophylaxis from ovarian hyperstimulation syndrome (OHSS): A potentially safer and more effective protocol

Vascular endothelial growth factor (VEGF) is the most important angiogenic mediator in ovarian hyperstimulation syndrome OHSS. Studies proved that cabergoline administration blocks the increase in vascular permeability via dephosphorylation of VEGF receptors and hence can be used as prophylactic agent against OHSS. This study aimed at evaluating the effectiveness of early administration of cabergoline in the prevention of OHSS in high risk cases prepared for ICSI. This case series study was conducted on 126 high risk patients prepared for ICSI using the fixed antagonist protocol. High risk patients were defined as having more than 20 follicles >12 mm in diameter, and/or E2 more than 3000 pg/ml when the size of the leading follicle is more than 15 mm. When the size of the leading follicle reached 15 mm, cabergoline was administered (0.5 mg/day) for 8 days. Patients were followed up clinically, ultrasonographically and hematologically. The final E2 was 6099.5 ± 2730 and the mean number of retrieved oocytes was 19.7 ± 7.8. The clinical pregnancy rate was 62/126 (49.2%). There were no significant changes (p > 0.05) comparing hematological parameters, renal function tests and liver function tests between the day of HCG and the day of blastocyst transfer. The incidence of severe OHSS in this group was 1/126 (0.9%), while moderate OHSS was 12 (9.5%) and there were no cases of critical OHSS. We concluded that early administration of cabergoline is a safe and potentially more effective approach for prophylaxis against OHSS in high risk cases.

The effect of luteal GnRH antagonist on moderate and severe early ovarian hyperstimulation syndrome during in vitro fertilization treatment: a prospective cohort study

PURPOSE

Ovarian hyperstimulation syndrome (OHSS) is a serious complication of assisted reproductive technology (ART) treatment. However, there are limited data regarding the ability of the luteal GnRH antagonist cetrorelix to reduce the incidence of moderate and severe OHSS, and the mechanism remains unclear. Thus, we designed a study to assess the effectiveness of cetrorelix to prevent early moderate and severe OHSS in high-risk patients undergoing controlled ovarian stimulation for IVF/ICSI.

METHODS

In this prospective cohort study, 105 patients with high-risk OHSS undergoing cryopreservation of all embryos were divided into two groups according to their personal choice. The cetrorelix group (n = 65) received 0.25 mg of cetrorelix by subcutaneous injection daily, from days 3 to 5 post-oocyte retrieval (POR); the control group (n = 40) received no drug. The primary outcome measures were the incidence and severity of early moderate and severe OHSS. Secondary measures included serum estradiol levels, ovarian volume, ascites volume, hematocrit values, and WBC count on days 3, 6, and 9 POR. VEGF and EGR-1 levels were assessed, and binary logistic regression analysis was applied to predict associations between clinical variables and OHSS.

RESULTS

Ninety-six patients were examined. The incidence of moderate and severe OHSS was significantly lower in the cetrorelix group than in the control group (18.03% and 37.14%, respectively; P = 0.037). Serum estradiol (P = 0.013), white blood cell count (P = 0.031), ascites volume (P = 0.036), EGR-1 (P = 0.025), and VEGF levels (P = 0.015) were significantly higher in the control group on day 6 POR than on day 3 POR, while no increase was observed between day 3 POR and day 6 POR in the cetrorelix group, indicating a faster regression of OHSS symptoms. Cetrorelix intervention was associated with the incidence and severity of OHSS (OR 0.29, 95% CI 0.11-0.78, P = 0.014).

CONCLUSION

Cetrorelix effectively reduces the incidence of early moderate and severe OHSS in high-risk women and decreases serum VEGF levels.