Prospective study of the clinical and laboratory parameters of patients in whom ovarian hyperstimulation syndrome developed during controlled ovarian hyperstimulation for in vitro fertilization

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.

Severe ovarian hyperstimulation syndrome induced by clomiphene: a case report

This article reported a rare case of severe ovarian hyperstimulation syndrome (OHSS) following oral clomiphene. The patient was instructed to take clomiphene on the 5th day of menstruation, 50 mg daily for 5 days, without any medical examination or laboratory tests before administration of clomiphene. The treatment outcome was ideal by conservative treatment. This reminded that full assessment and risk prediction should be performed before the prescription of clomiphene. And clomiphene should be used only when indicated. What's more, high risk factors of the particular patient should be taken into full consideration.

GnRH agonist-triggering ovulation in women with advanced age

This study evaluates the effect of GnRH agonist (GnRHa) trigger for ovulation induction among women with advanced maternal age (AMA). This is a retrospective study performed at a single assisted reproductive technology centre, 2012 to 2020. A total of 306 patients with 515 IVF cycles who were triggered with GnRHa for Ovum Pick Up (OPU), were divided into two groups according to maternal age: age ≥ 40 and age < 40. The groups were compared for demographics, stimulation parameters of IVF treatment and IVF treatment outcomes. The patients in the age < 40 group were approximately 10 years younger than the patients in the age ≥ 40 group (31 ± 5.4 vs. 41.5 ± 1.3 years, p < 0.001). The age ≥ 40 group had significantly higher mean E2/retrieved oocytes ratio, compared to the age < 40 group (310.3 ± 200.6 pg/ml vs. 239 ± 168.2 pg/ml, p = 0.003), and a lower mean MII/retrieved oocyte (35 ± 37.8 vs. 43.4 ± 35.9, p = 0.05, respectively). Multivariable logistic regression analysis for E2/retrieved oocytes demonstrated that age < 40 and total dose of gonadotropins were significant variables. In conclusion, GnRHa for ovulation triggering in high responder patients prior to OPU appears to be a good option for AMA. However, this population is characterized by different parameters of ovarian response that require further evaluation.

Extended Injection Intervals of Gonadotropins by Intradermal Administration in IVF Treatment

CONTEXT

Gonadotropins can be administered every 5 days under intradermal injection in in vitro fertilization (IVF) treatment.

OBJECTIVE

To explore the effectiveness of intradermal injection of recombinant human FSH (rhFSH) for women undergoing IVF.

METHODS

Women who received their first IVF treatment enrolled in this prospective intervention in 2018. All women received a bolus of 900 IU rhFSH intradermally at day 2 of the treatment cycle followed by additional dosage of rhFSH at day 7 and/or day 10. The main outcome measures included the total dose of rhFSH and number of injections required, sequential serum FSH level detected, and number of mature oocytes retrieved.

RESULTS

Seventy women completed the study. On average, 2.31 ± 0.73 injections and 1662 ± 397 IU of rhFSH were administered. While the baseline FSH level was 5.6 ± 2.2 IU/L, the serum concentrations of FSH after rhFSH administration were 35.3 ± 7.0 on the first day (24 hours) and 10.7 ± 3.7 IU/L on the fifth day (120 hours). A total of 10.5 ± 6.6 mature oocytes were retrieved, resulting in 7.3 ± 5.1 pronuclear embryos; 1.8 ± 0.6 embryos were transferred to the uterus. Our findings resulted in 72% fertilization, 91% cleavage, 31% implantation, and 36% live birth rates. Although fewer larger follicles were found, noninferiority results were noted in the mature oocytes retrieved, good embryos available, and clinical pregnancy rate compared with those received conventional daily subcutaneous rhFSH administration.

CONCLUSION

Intradermal administration of rhFSH, with a smaller dose of rhFSH and fewer injections, may achieve the goal of a cost-effective and more patient-friendly regimen.

Predictive Factors for Recovery Time in Conceived Women Suffering From Moderate to Severe Ovarian Hyperstimulation Syndrome

OBJECTIVE

This study aimed to evaluate potential predictors for recovery time in pregnant patients with moderate to severe ovarian hyperstimulation syndrome (OHSS).

METHODS

A total of 424 pregnant patients with moderate to severe OHSS who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) were retrospectively identified. The clinical features and laboratory findings within 24 h after admission were collected. Treatment for OHSS was carried out according to standard procedures, including fluid replacement therapy, human albumin, aspirin, low-molecular-weight heparin, and paracentesis, when necessary. Patients were discharged from the hospital when the tmorning hematocrit was <40% and no obvious clinically relevant symptoms existed, such as abdominal distension, abdominal pain, and shortness of breath. Meanwhile, ultrasound indicating little pleural or abdominal effusion and biochemical abnormalities returning to normal were required. Spearman's correlation analysis was used to assess the association between the blood-related parameters and recovery time. Multiple linear regression models were used to assess the relationship between the clinical or laboratory parameters and recovery time.

RESULTS

The median recovery time of these patients was 11 days. In Spearman's correlation test, leukocytes, hemoglobin, platelets, hematocrit, creatinine, prothrombin time (PT), fibrinogen (Fib), D-dimer, and fibrinogen degradation products (FDPs) were positively correlated with recovery time. On the other hand, albumin and thrombin time (TT) were negatively correlated with recovery time. Multiple linear regression analysis showed that polycystic ovary syndrome (PCOS), hemoglobin, platelets, albumin, and Fib were significantly associated with the recovery time of patients with OHSS (p = 0.023, p < 0.001, p = 0.007, p < 0.001, and p = 0.019, respectively).

CONCLUSIONS

In pregnant patients with OHSS, PCOS and hypoalbuminemia were associated with a significantly longer recovery time. Meanwhile, the recovery time was longer when patients have high levels of hemoglobin, platelets, and Fib.

A Histopathological Evaluation of Ovarian Hyperstimulation Syndrome on Reproductive and Vital Organs and the Role of the VEGF-PKA Pathway in a Mouse Model

Ovarian hyperstimulation syndrome (OHSS) is one of the most common and iatrogenic complications of in vitro fertilization therapy, which is an exaggerated response to excess hormones resulting in the development of a large number of maturing follicles. Although the complications of and reasons for the condition are well known, the overall histopathological effects on systemic organs and the extent of the damage have not been fully elucidated. Besides, the mechanism that underlies the situation is not very well known. The aim of the present work was to analyse the histopathological effects of OHSS on reproductive (uterus and ovary) and vital organs (liver and kidney) and the possible role of the VEGF-PKA pathway in triggering the condition. Balb/c mice were used to establish an OHSS model. The OHSS group were injected with overdose PMSG while the normal responder group were injected with an optimal dose. Histopathological evaluation was utilised in the liver, kidney, ovary, and uterus stained with hematoxylin and eosin, Masson's trichrome, and periodic acid-Schiff stain. The expression profiles of VEGF (vascular endothelial growth factor), PKA (protein kinase A), and p-PKA (an activated form of PKA) were detected with immunohistochemistry and Western blotting. OHSS was demonstrated to have a negative histopathological effect on all of the organs analysed. These effects were associated with an overall increase in the expression levels of VEGF, PKA, and p-PKA. OHSS has a serious histopathological negative effect on the systemic and reproductive organs and is proven to affect overall health, and thus should be considered a dangerous complication during ART techniques. The activation of the VEGF-PKA pathway, which is indicated by the expression levels of VEGF, PKA, and p-PKA, is demonstrated to accompany this complication, which should be further elucidated to understand the mechanisms underlying the condition.

The influence of obesity on incidence of complications in patients hospitalized with ovarian hyperstimulation syndrome

OBJECTIVE

To study the impact of body habitus on risk of complications resulting from ovarian hyperstimulation syndrome (OHSS) in hospitalized patients.

METHODS

This is a retrospective observational study examining the National Inpatient Sample between January 2012 and September 2015. Patients were women < 50 years of age diagnosed with OHSS, classified as non-obese, class I-II obesity, or class III obesity. Intervention included multinomial logistic regression to identify factors associated with obesity and binary logistic regression for independent risk factors for complications. Main outcome measures were incidence of (i) any or (ii) multiple complication(s).

RESULTS

Of 2745 women hospitalized with OHSS, 2440 (88.9%) were non-obese, 155 (5.6%) had class I-II obesity, and 150 (5.5%) had class III obesity. Obese women (either class I-II or III) had a higher degree of comorbidity, had lower incomes, and were less likely to have private insurance than non-obese women (all P < 0.001). Obese women had lower rates of OHSS-related complications than non-obese women (any complication: non-obese 65.2%, class I-II 54.8%, and class III 46.7%, P < 0.001; and multiple complications: non-obese 38.5%, class I-II 32.3%, and class III 20.0%, P < 0.001). In the multivariable model, obesity remained independently associated with a decreased risk of complications (class I-II odds ratio 0.57, 95% confidence interval 0.39-0.83, P = 0.003; class III odds ratio 0.30, 95% confidence interval 0.20-0.44, P < 0.001). Obese women were also less likely to require paracentesis (non-obese 32.8%, class I-II 9.7%, and class III 13.3%, P < 0.001).

CONCLUSION

Our study suggests that obesity is associated with decreased OHSS-related complication rates in hospitalized patients.

Fertility Issues in Polycystic Ovarian Disease: A Systematic Approach

The triad of hirsutism, amenorrhea, and enlarged polycystic ovaries first was described in 1935 and later become known as polycystic ovarian syndrome (PCOS). Women with PCOS are more likely to have cardiometabolic challenges that also have an indirect relationship to their fertility and fertility outcomes. Despite these challenges, their fertile life span appears to be longer. Ovulation induction is considered first-line management of infertility in women with PCOS, with letrozole superior to clomiphene. Women with PCOS undergoing in vitro fertilization are high risk for ovarian hyperstimulation syndrome but also have a higher live birth rate compared with controls.

The Goto-Kakizaki rat is a spontaneous prototypical rodent model of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is characterized by an oligo-anovulation, hyperandrogenism and polycystic ovarian morphology combined with major metabolic disturbances. However, despite the high prevalence and the human and economic consequences of this syndrome, its etiology remains unknown. In this study, we show that female Goto-Kakizaki (GK) rats, a type 2 diabetes mellitus model, encapsulate naturally all the reproductive and metabolic hallmarks of lean women with PCOS at puberty and in adulthood. The analysis of their gestation and of their fetuses demonstrates that this PCOS-like phenotype is developmentally programmed. GK rats also develop features of ovarian hyperstimulation syndrome. Lastly, a comparison between GK rats and a cohort of women with PCOS reveals a similar reproductive signature. Thus, this spontaneous rodent model of PCOS represents an original tool for the identification of the mechanisms involved in its pathogenesis and for the development of novel strategies for its treatment.

Spontaneous Ovarian Hyperstimulation Syndrome: A Report of Two Cases from Different Pathogenesis

Spontaneous ovarian hyperstimulation syndrome (s-OHSS) is a rare finding that occurs in early pregnancy. There is a rapidly increasing ovarian size secreting vasoactive substances that lead to fluid shift into third spaces. This occurs in the absence of exogenous hormonal therapy. We present two cases of s-OHSS. A 35-year-old gravida 4 para 3 presented with complaints of progressive abdominal pain, distension, nausea, vomiting, and difficulty in breathing at 10 weeks gestation. On imaging, a singleton intrauterine gestation, enlarged ovaries containing multiple cysts, and moderate ascites were seen. Second, a 17-year-old primigravida presented with abdominal distension and pain and bleeding per vaginam following 4 months amenorrhea. A bulky uterus containing a large hyperechoic structure with multiple cystic spaces in keeping complete molar gestation and enlarged ovaries containing multiple cysts were seen on ultrasound imaging. The singleton gestation was managed successfully to term with conservative therapy tailored to clinical symptoms.

Ovarian hyperstimulation syndrome after assisted reproductive technologies: trends, predictors, and pregnancy outcomes

OBJECTIVES

To assess trends, predictors, and perinatal outcomes of ovarian hyperstimulation syndrome (OHSS) associated with in vitro fertilization (IVF) cycles in the United States.

DESIGN

Retrospective cohort study using National Assisted Reproductive Technology Surveillance System (NASS) data.

SETTING

Not applicable.

PATIENT(S)

Fresh autologous and embryo-banking cycles performed from 2000 to 2015.

INTERVENTIONS(S)

None.

MAIN OUTCOME MEASURE(S)

OHSS, first-trimester loss, second-trimester loss, stillbirth, low birth weight, and preterm delivery.

RESULT(S)

The proportion of IVF cycles complicated by OHSS increased from 10.0 to 14.3 cases per 1,000 from 2000 to 2006, and decreased to 5.3 per 1,000 from 2006 to 2015. The risk of OHSS was highest for cycles with more than 30 oocytes retrieved (adjusted risk ratio [aRR] 3.85). OHSS was associated with a diagnosis of ovulatory disorder (aRR 2.61), tubal factor (aRR 1.14), uterine factor (aRR 1.17) and cycles resulting in pregnancy (aRR 3.12). In singleton pregnancies, OHSS was associated with increased risk of low birth weight (aRR 1.29) and preterm delivery (aRR 1.32). In twin pregnancies, OHSS was associated with an increased risk of second-trimester loss (aRR 1.81), low birth weight (aRR 1.06), and preterm delivery (aRR 1.16).

CONCLUSION(S)

Modifiable predictive factors for OHSS include number of oocytes retrieved, pregnancy following fresh embryo transfer, and the type of medication used for pituitary suppression during controlled ovarian hyperstimulation. Patients affected by OHSS had a higher risk of preterm delivery and low birth weight. Clinicians should take measures to reduce the risk of OHSS whenever possible.

A decision-making algorithm for performing or cancelling embryo transfer in patients at high risk for ovarian hyperstimulation syndrome after triggering final oocyte maturation with hCG

STUDY QUESTION

Can the grade of ascites, haematocrit (Ht), white blood cell (WBC) count and maximal ovarian diameter (MOD) measured on Day 3 be used to construct a decision-making algorithm for performing or cancelling embryo transfer in patients at high risk for severe ovarian hyperstimulation syndrome (OHSS) after an hCG trigger?

SUMMARY ANSWER

Using cut-offs of ascites grade>2, Ht>39.2%, WBC>12 900/mm³ and MOD>85 mm on Day 3, a decision-making algorithm was constructed that could predict subsequent development of severe OHSS on Day 5 with an AUC of 0.93, a sensitivity of 88.5% and a specificity of 84.2% in high-risk patients triggered with hCG.

WHAT IS KNOWN ALREADY

Despite the increasing popularity of GnRH agonist trigger for final oocyte maturation as a way to prevent OHSS, ≥75% of IVF cycles still involve an hCG trigger. Numerous risk factors and predictive models of OHSS have been proposed, but the measurement of these early predictors is restricted either prior to or during the controlled ovarian stimulation. In high-risk patients triggered with hCG, the identification of luteal-phase predictors assessed post-oocyte retrieval, which reflect the pathophysiological changes leading to severe early OHSS, is currently lacking.

STUDY DESIGN, SIZE, DURATION

A retrospective study of 321 patients at high risk for severe OHSS following hCG triggering of final oocyte maturation. High risk for OHSS was defined as the presence of at least 19 follicles ≥11 mm on the day of triggering of final oocyte maturation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The study includes IVF/ICSI patients at high risk for developing severe OHSS, who administered hCG to trigger final oocyte maturation. Ascites grade, MOD, Ht and WBC were assessed in the luteal phase starting from the day of oocyte retrieval. Outcome measures were the optimal thresholds of ascites grade, MOD, Ht and WBC measured on Day 3 post-oocyte retrieval to predict subsequent severe OHSS development on Day 5. These criteria were used to construct a decision-making algorithm for embryo transfer, based on the estimated probability of severe OHSS development on Day 5.

MAIN RESULTS AND THE ROLE OF CHANCE

The optimal Day 3 cutoffs for severe OHSS prediction on Day 5 were ascites grade>2, Ht>39.2%, WBC>12 900/mm³ and MOD>85 mm. The probability of severe OHSS with no criteria fulfilled on Day 3 is 0% (95% CI: 0–5.5); with one criterion, 0.8% (95% CI: 0.15–4.6); with two criteria, 13.3% (95% CI: 7.4–22.8); with three criteria, 37.2% (95% CI: 24.4–52.1); and with four criteria, 88.9% (95% CI, 67.2–98.1). The predictive model of severe OHSS had an AUC of 0.93 with a sensitivity of 88.5% and a specificity of 84.2%.

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective study, and therefore, it cannot be excluded that non-apparent sources of bias might be present. In addition, we acknowledge the lack of external validation of our model. We have created a web-based calculator (http://ohsspredict.org), for wider access and usage of our tool. By inserting the values of ascites grade, MOD, Ht and WBC of high-risk patients on Day 3 after oocyte retrieval, the clinician instantly receives the predicted probability of severe OHSS development on Day 5.

WIDER IMPLICATIONS OF THE FINDINGS

The present study describes a novel decision-making algorithm for embryo transfer based on ascites, Ht, WBC and MOD measurements on Day 3. The algorithm may be useful for the management of high-risk patients triggered with hCG and for helping the clinician’s decision to proceed with, or to cancel, embryo transfer. It must be emphasized that the availability of the present decision-making algorithm should in no way encourage the use of hCG trigger in patients at high risk for OHSS. In these patients, the recommended approach is the use of GnRH antagonist protocols, GnRH agonist trigger and elective embryo cryopreservation. In addition, in patients triggered with hCG, freezing all embryos and luteal-phase GnRH antagonist administration should be considered for the outpatient management of severe early OHSS and prevention of late OHSS.

STUDY FUNDING/COMPETING INTEREST(S)

NHMRC Early Career Fellowship (GNT1147154) to C.A.V. No conflict of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Acute Kidney Injury Due to Ovarian Hyperstimulation Syndrome

Ovarian hyperstimulation syndrome (OHSS) is a complication of assisted reproductive treatments such as in vitro fertilization (IVF). The pathophysiology of severe OHSS includes a humorally mediated capillary leak syndrome that is predominantly centered on the intra-abdominal space. Severe OHSS is frequently complicated by acute kidney injury (AKI), which can be due to any of a variety of mechanisms, each requiring a different management strategy. Mechanisms of AKI in severe OHSS include intravascular volume depletion, kidney edema due to capillary leak, intra-abdominal hypertension or compartment syndrome, and obstructive uropathy due to ovarian enlargement. We present a teaching case of severe OHSS complicated by AKI in a woman with underlying stage 4 chronic kidney disease. She had been undergoing IVF with plans to subsequently use a gestational carrier (surrogate) for pregnancy. We use this case to review the presentation and pathophysiology of OHSS complicated by AKI. In addition, we review the management of AKI in OHSS, in particular, the role of paracentesis and/or culdocentesis to manage tense ascites. Last, we highlight that similar cases may occur more frequently in the future given that IVF with subsequent use of a gestational carrier is increasingly being used for patients with comorbid conditions that can be exacerbated by pregnancy, such as advanced chronic kidney disease.

Is thromboprophylaxis cost effective in ovarian hyperstimulation syndrome: A systematic review and cost analysis

BACKGROUND

The majority of serious thromboembolic events occurring in assisted reproductive technologies (ART) are in women with ovarian hyperstimulation syndrome (OHSS).

OBJECTIVES

The purpose of this study was to present a thorough review and cost analysis regarding the use of venous thromboembolism (VTE) prophylaxis in OHSS to inform clinical management.

DATA SOURCES

Databases used were Pubmed and Embase, in addition to checking reference lists of retrieved articles (inception to November 2017).

METHODS

The systematic search strategy identified 365 titles and abstracts. Articles included in the qualitative synthesis had identified venous thrombosis incidence rates or ratios. A separate search for the cost model was conducted recognizing all associated complications of VTE. The decision tree was modeled to best fit the patient population and a sensitivity analysis was performed over a range of variables.

RESULTS

The cost of VTE event per OHSS patient not on prophylaxis was €5940 (range €3405 to €38,727), versus €4134 (€2705 to €23,192) per event per patient on prophylaxis, amounting to a saving of (€19 to €23,192) per VTE per patient. Sensitivity analysis found VTE prophyaxis to be cost effective if the incidence of VTE in the OHSS population was greater than 2.79%. Prophylactic therapy was cost effective through 16 weeks of treatment.

LIMITATIONS

OHSS is infrequent and hence, the incidence of VTE in patients with OHSS is low; therefore, the data used to inform the incidence of VTE in OHSS in the model carry some uncertainty. Further, low molecular weight heparin (LMWH) has side effects therefore individualization of care must be considered.

CONCLUSIONS

With the increasing incidence of infertility and requirement for ART, thromboembolism in OHSS poses a major health threat for patients. VTE prophylaxis using enoxaparin was cost effective in patients with severe OHSS over a wide range of costs and incidences. Prophylaxis was also cost effective through the completion of the first trimester of pregnancy.

Ultrasound and hematological changes during early luteal phase in women at high risk for developing ovarian hyperstimulation syndrome

OBJECTIVE

To assess ultrasound and hematological changes during the early luteal phase following triggering of final oocyte maturation with human chorionic gonadotropin (hCG) in women at high risk for developing ovarian hyperstimulation syndrome (OHSS).

METHODS

This was a retrospective cohort study of 319 women undergoing in-vitro fertilization who were at high risk for OHSS following administration of hCG for the triggering of final oocyte maturation. Patients were treated with a gonadotropin-releasing hormone agonist or antagonist protocol and were monitored for 5 days post-oocyte retrieval (early luteal phase). Severe OHSS was diagnosed in the presence of at least moderate ascites and two or more of the following: maximum ovarian diameter (MOD) > 100 mm, hematocrit (Ht) > 45%, white blood cell count (WBC) > 15 000/mm³ , hydrothorax, dyspnea and oliguria. Outcome measures included change in Ht, ascites grade, WBC and MOD, as well as the association between these changes during the early luteal phase.

RESULTS

Ascites grade, Ht and WBC increased significantly (P ≤ 0.001) during the early luteal phase, both in patients who developed and in those who did not develop severe early OHSS. MOD increased significantly (P = 0.001) only in patients who developed severe early OHSS. On multivariable analysis, both time following oocyte retrieval and whether severe early OHSS developed were significantly associated with ascites grade, Ht, WBC and MOD; furthermore, there was also a significant interaction between time and development of severe early OHSS for all four variables (P ≤ 0.001).

CONCLUSIONS

In women at high risk of OHSS, ascites grade, Ht and WBC significantly increased with time over the 5-day observation period, in line with the pathophysiology of the syndrome. Our data support the use of MOD in the diagnosis of severe early OHSS, and provide novel evidence for the role of change in Ht as a patient-specific hemoconcentration marker during development of OHSS. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

A novel oocyte maturation trigger using 1500 IU of human chorionic gonadotropin plus 450 IU of follicle-stimulating hormone may decrease ovarian hyperstimulation syndrome across all in vitro fertilization stimulation protocols

PURPOSE

Modification of the trigger used to induce final oocyte maturation in in vitro fertilization (IVF) is a major strategy used to reduce the risk of ovarian hyperstimulation syndrome (OHSS). A novel trigger composed of 1500 IU of human chorionic gonadotropin (hCG) plus 450 IU of follicle-stimulating hormone (FSH) has been developed to reduce OHSS risk. This study compares outcomes of the novel trigger to conventional triggers used in high-risk OHSS patients undergoing IVF.

METHODS

In this retrospective cohort study, IVF cycles at high risk for OHSS based on a serum estradiol > 5000 pg/ml on trigger day conducted between January 2008 and February 2016 were evaluated. Oocyte maturation was induced with the novel trigger (1500 IU hCG plus 450 IU FSH) or a conventional trigger [3300 IU hCG, gonadotropin-releasing hormone agonist (GnRHa) alone, or GnRHa plus 1500 IU hCG]. IVF cycle outcomes were compared. Trigger strategies were examined for associations with OHSS development using logistic regression.

RESULTS

Among 298 eligible IVF cycles identified, there were no differences in oocyte maturation, fertilization, embryo quality, or pregnancy outcomes among all triggers. After adjusting for serum estradiol level and number of follicles, the novel trigger was associated with lower odds of OHSS symptom development compared to the 3300 IU hCG and GnRHa plus hCG 1500 IU triggers (p = 0.007 and 0.04, respectively).

CONCLUSIONS

This study suggests that 1500 IU hCG plus 450 IU FSH may be associated with decreased OHSS symptoms compared to conventional triggers, while producing similar IVF and pregnancy outcomes. More important, this novel trigger may provide a superior alternative in down-regulated cycles and in patients with hypothalamic dysfunction where GnRHa triggers cannot be utilized.

What is the best predictor of severe ovarian hyperstimulation syndrome in IVF? A cohort study

PURPOSE

The purpose of the present study is to study what is the best predictor of severe ovarian hyperstimulation syndrome (OHSS) in IVF.

METHODS

This is a retrospective analysis of all consecutive IVF/intracytoplasmic injection cycles performed during a 5-year period (2009-2014) in a single university fertility centre. All fresh IVF cycles where ovarian stimulation was performed with gonadotrophins and GnRH agonists or antagonists and triggering of final oocyte maturation was induced with the administration of urinary or recombinant hCG were analyzed (2982 patients undergoing 5493 cycles). Because some patients contributed more than one cycle, the analysis of the data was performed with the use of generalized estimating equation (GEE).

RESULTS

Severe OHSS was diagnosed in 20 cycles (0.36%, 95% CI 0.20-0.52). The number of follicles ≥10 mm on the day of triggering final oocyte maturation represents the best predictor of severe OHSS in IVF cycles. The cutoff in the number of follicles ≥10 mm with the best capacity to discriminate between women that will and will not develop severe OHSS was ≥15.

CONCLUSION

The presence of more than 15 follicles ≥10 mm on the day of triggering final oocyte maturation represents the best predictor of severe OHSS in IVF cycles.

[Ovarian hyperstimulation syndrome after stimulation with highly purified hMGfor in vitro fertilization: Observational study SHOview]

OBJECTIVE

Data on the incidence and severity of ovarian hyperstimulation syndrome (OHSS) in France are limited.

METHODS

Prospective observational multicentric study (23 French centers of IVF) in a cohort of 421 women treated with highly purified hMG (HP-hMG) for the first or second cycle of IVF with or without ICSI. The primary objective was to assess the incidence of moderate to severe OHSS in this cohort.

RESULTS

At inclusion, 172 patients (40.9%) were considered at risk of OHSS by the physicians. The main measures for risk minimization taken by the physicians rested on initial dose of HP-hMG and protocol choice. At the end of the follow-up (4 months in average), the rate of OHSS moderate to severe was 2.4% (confidence interval 95%: 1.1-4.3%) for the studied IVF cycle. OHSS was severe for 3 women (0.7%) and moderate for 7 women (1.7%).

CONCLUSION

This rate of OHSS after IVF is at the lower limit of the rates reported in the literature for OHSS. This study brings reassuring epidemiological data on the rate of OHSS in women at risk. The measures taken by the physicians to minimize the risk of OHSS could have contributed to this low incidence.

Effect of letrozole on moderate and severe early-onset ovarian hyperstimulation syndrome in high-risk women: a prospective randomized trial

BACKGROUND

Ovarian hyperstimulation syndrome is an iatrogenic complication of controlled ovarian stimulation. Early ovarian hyperstimulation syndrome occurs during luteal phase of controlled ovarian stimulation within 9 days after human chorionic gonadotropin trigger and reflects an acute consequence of this hormone on the ovaries. Late ovarian hyperstimulation syndrome occurs 10 or more days after human chorionic gonadotropin trigger and reflects increased endogenous human chorionic gonadotropin levels following pregnancy. Human chorionic gonadotropin stimulates granulosa-lutein cells to produce vascular endothelial growth factor messenger RNAs, which in turn raises serum vascular endothelial growth factor concentration and increases vascular permeability in women with ovarian hyperstimulation syndrome. Efforts to reduce the incidence and severity of ovarian hyperstimulation syndrome after oocyte retrieval, and in particular primary prevention efforts, are vital to prevent thrombogenesis and other serious complications.

OBJECTIVE

The objective of the study was to compare the efficacy of letrozole, an aromatase inhibitor, with aspirin in primary prevention of early ovarian hyperstimulation syndrome and to compare vascular endothelial growth factor levels between groups.

STUDY DESIGN

Participants in this prospective randomized trial included 238 participants undergoing cryopreservation of the whole embryos after oocyte retrieval with at least 1 of the following high-risk factors for ovarian hyperstimulation syndrome: oocyte retrieval ≥25; estradiol level ≥5000 pg/mL on the day of human chorionic gonadotropin administration; and clinical or ultrasonographic evidence of ovarian hyperstimulation syndrome on the day of oocyte retrieval, such as ultrasonographic evidence of ascites. After human chorionic gonadotropin triggering, experimental (119 cases) and control (119 cases) groups received letrozole and aspirin, respectively, for 5 days. The 5 categories of ovarian hyperstimulation syndrome include no, yes-mild, yes-moderate, yes-severe, and yes-critical. The primary outcome was the incidence and severity of early ovarian hyperstimulation syndrome. The secondary outcome included vascular endothelial growth factor level both on the second and seventh day after the human chorionic gonadotropin trigger, and clinical and laboratory features of ovarian hyperstimulation syndrome symptoms.

RESULTS

The incidence of ovarian hyperstimulation syndrome was significantly higher in women receiving aspirin, compared with letrozole (90.2% vs 80.4%, P = .044). Moderate and severe ovarian hyperstimulation syndrome was also higher in the aspirin group, 45.1%, compared with the letrozole group, 25.0% (P = .002). Moreover, the duration of luteal phase was shortened in letrozole group compared with aspirin group (8.1 ± 1.1 days vs 10.5 ± 1.9 days, P < .001). The vascular endothelial growth factor level was significantly higher in the letrozole-treated group than aspirin-treated group (0.49 ± 0.26 vs 0.42 ± 0.22, P = .029).

CONCLUSION

Letrozole was more effective than aspirin in decreasing the incidence of moderate and severe early-onset ovarian hyperstimulation syndrome. Our results indicate that ovarian hyperstimulation syndrome might be caused through a luteolytic effect rather than through modulation of vascular endothelial growth factor, racing by a decline in estradiol and termination of early-onset ovarian hyperstimulation syndrome in advance in high-risk women with cryopreservation of the whole embryos.

Predictors of Paracentesis in Women with Severe Ovarian Hyperstimulation Syndrome: A Retrospective Cohort Study

BACKGROUND

To identify predictors of paracentesis in women with severe ovarian hyperstimulation syndrome (OHSS).

METHODS

In a retrospective cohort study, we assessed patient characteristics and outcome measures of women with severe OHSS Golan grade II/III from 1996 to 2010 using univariate and multivariate analyses with the number of paracenteses as the main outcome.

RESULTS

Three hundred ninety four women with OHSS Golan grade II (n = 40) and grade III (n = 354) were included in the study. Paracentesis was performed in 108/394 (27%) of these women. One paracentesis was performed in 63 (16%), 2 paracenteses in 26 (6%), and ≥3 paracenteses 19 (5%) women, respectively. No thrombotic or cerebrovascular morbidity occurred. The mortality of the cohort was 0/394 (0%). In a univariate analysis, late onset OHSS (p = 0.02), pregnancy (p < 0.001), human chorionic gonadotropin use (p = 0.02), ovarian diameter (p = 0.006), and elevated serum levels of alanine aminotransferase (p < 0.001), hematocrit (p < 0.001), leucocytes (p < 0.001), thrombocytes (p < 0.001), and uric acid (p < 0.001) were associated with paracentesis. In a multivariate logistic regression analysis, only alanine aminotransferase (OR 1.006; 95% CI 1.001-1.01) and hematocrit (OR 1.16; 95% CI 1.05-1.27) were independently associated with paracentesis.

CONCLUSION

Alanine aminotransferase and hematocrit at initial presentation are independent predictors of paracentesis.

Inhibition of angiopoietin-1 (ANGPT1) affects vascular integrity in ovarian hyperstimulation syndrome (OHSS)

Ovarian hyperstimulation syndrome (OHSS) is a complication of ovarian stimulation with gonadotrophins following human chorionic gonadotrophin (hCG) administration. The relationship between hCG and OHSS is partly mediated via the production of angiogenic factors, such as vascular endothelial growth factor A (VEGFA) and angiopoietins (ANGPTs). Here, we investigated the effect of ANGPT1 inhibition on ovarian angiogenesis in follicular fluid (FF) from women at risk of OHSS, using the chorioallantoic membrane (CAM) of quail embryos as an experimental model. We also analysed cytoskeletal changes and endothelial junction protein expression induced by this FF in the presence or absence of an ANGPT1-neutralising antibody in endothelial cell cultures. The presence of this antibody restored the number of vascular branch points and integrin αvβ3 levels in the CAMs to control values. ANGPT1 inhibition in FF from OHSS patients also restored the levels of claudin-5, vascular endothelial cadherin and phosphorylated β-catenin and partially reversed actin redistribution in endothelial cells. Our findings suggest that ANGPT1 increases pathophysiological angiogenesis in patients at risk of OHSS by acting on tight and adherens junction proteins. Elucidating the mechanisms by which ANGPT1 regulates vascular development and cell–cell junctions in OHSS will contribute to identifying new therapeutic targets for the treatment of human diseases with aberrant vascular leakage.

Consensus statement on prevention and detection of ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome is an important condition with considerable morbidity and a small risk of mortality, which most commonly results as an iatrogenic condition following follicular stimulation of the ovaries.

AIM

To produce evidence-based and consensus statements on the prevention and detection of ovarian hyperstimulation syndrome (OHSS).

METHOD

The CREI Consensus Group met in 2008 and identified issues for inclusion and review. Review of the available evidence was conducted and consensus statements prepared. Areas of dissent of expert opinion and for further research were noted.

RESULTS

The group considered that there is a need for standardisation of the definition and classification of the clinical syndrome of OHSS to allow further conclusive research. Interventions with evidence of effect in reducing OHSS include the use of metformin in women with PCOS, use of GnRH antagonist rather than GnRH agonist and use of GnRH agonist triggers in GnRH antagonist stimulation cycles. The consensus view was that reducing the dose of FSH, freezing all embryos and transferring a single embryo were appropriate interventions to reduce OHSS. Agreement could not be reached on coasting, the lowest number of oocytes to consider freezing all embryos and management after cancellation of oocyte collection.

CONCLUSION

OHSS is a serious condition for which there are a number of proven preventative strategies. OHSS is an area requiring ongoing research and development of a universally agreed definition will allow development of optimal prevention strategies and facilitate improved early detection of women at risk.

Effect of follicle-stimulating hormone receptor Asn680Ser polymorphism on the outcomes of controlled ovarian hyperstimulation: an updated meta-analysis of 16 cohort studies

PURPOSE

The purpose of this study is to evaluate the influence of follicle-stimulating hormone receptor (FSHR) Asn680Ser polymorphism on the ovarian response to exogenous follicle-stimulating hormone (FSH) and clinical outcomes in women undergoing controlled ovarian hyperstimulation (COH).

METHODS

A database search was conducted to identify the eligible studies that investigated the effect of FSHR Asn680Ser polymorphism on ovarian response and clinical outcomes. A pooled analysis was performed with the odds ratio (OR) or weighted mean difference (WMD) and their respective 95 % confidence interval (CI) by the STATA software with random effects model.

RESULTS

Sixteen cohort studies comprising a total of 4287 subjects were included. The number of retrieved oocytes was significantly fewer in subjects with the SS genotype at position 680, compared to subjects with the NN or NS genotype (WMD = -1.36, 95 % CI = -1.85 to -0.87). Lack of association was detected between the genotypes (SS genotype vs. NN or NS genotype) and clinical outcomes such as exogenous FSH dose (WMD = 98.96 IU, 95 % CI = -22.33 to 220.24), poor response (OR = 1.08, 95 % CI = 0.71-1.64), ovarian hyperstimulation syndrome (OHSS) (OR = 1.58, 95 % CI = 0.41-6.07), and clinical pregnancy rate (OR = 1.10, 95 % CI = 0.86-1.40). However, poor ovarian response and number of retrieved oocytes were significantly influenced by the Asn680Ser polymorphism in the Asian subjects. In addition, no publication bias was detected.

CONCLUSION

FSHR Asn680Ser polymorphism might be a significant biomarker for predicting the number of retrieved oocytes and poor response, especially in Asian subjects. Other outcomes such as exogenous FSH dose, OHSS, and pregnancy rate were not influenced by FSHR Asn680Ser polymorphism.

Can steroidal ovarian suppression during the luteal phase after oocyte retrieval reduce the risk of severe OHSS?

Background

Ovarian stimulation in IVF cycle results in luteal supraphysiological steroid concentrations especially for high response patients. The aim of this study was to evaluate the efficacy of ovarian steroid hormone suppression in luteal phase after oocyte retrieval for preventing severe ovarian hyperstimulation syndrome (OHSS) in high-risk patients with embryo cryopreservation.

Methods

281 patients with high risk of OHSS were enrolled in this study among 4735 infertile women undergoing their first IVF treatment. The subjects were allocated into treatment and control group. The treatment group (n = 161) received letrozole (n = 43), mifepristone (n = 51), cetrotide (n = 39) and three-drug combinations (n = 28) during the luteal phase after oocyte retrieval, respectively. The control group (n = 120) received no medicine. Fertilization rate, good embryo rate, serum steroid concentration, clinical outcome, and incidence of severe OHSS were compared between the two groups.

Results

On days 2, 5 and 8 after oocyte retrieval, serum estradiol levels in the letrozole and three-drug combination therapy group were significantly lower than in the other three groups at the same time (P < 0.001, respectively). There were no significantly difference of serum luteinizing hormone concentration on days 2, 5 and 8 and progesterone concentration on day 8 after oocyte retreival among the five groups (P > 0.05, respectively). Compared with the control group, the incidence of severe OHSS, the paracentesis rate, the duration of hospitalization and the days of luteal phase in each subgroup of treatment groups was not significantly decreased (P > 0.05, respectively).

Conclusions

Our findings indicate that steroidal ovarian suppression in luteal phase after oocyte retrieval seems to be unable to prevent severe OHSS in high-risk patients with embryo cryopreservation.

LAPS-FSH: a new and effective long-acting follicle-stimulating hormone analogue for the treatment of infertility

Although several long-acting follicle-stimulating hormone (FSH) therapies have been developed to enhance the ovarian response, a disadvantage of FSH therapy is its relatively short half-life, which requires women to receive one to two injections per day for almost 2 weeks. In the present study, we developed a novel FSH analogue by conjugating recombinant human FSH (rhFSH) and the constant region of the human immunoglobulin G4 fragment via non-peptidyl linkers. The efficacy of the FSH analogue was evaluated in vitro by cAMP level assessments, pharmacokinetic studies and a determination of ovarian weight and by comparing these findings with the results from other FSH analogues. In addition, the total number of antral and Graafian follicles was determined after 7 days of treatment with control, 6µgkg(-1) follitropin β, 6, 12 or 42µgkg(-1) corifollitropin α or 3, 6 or 12µgkg(-1) long acting protein/peptide discovery-follicle-stimulating hormone (LAPS-FSH). As a result, the animals treated with 12µgkg(-1) LAPS-FSH produced additional and larger healthy follicles. These data demonstrate that LAPS-FSH promotes growth and inhibits atresia of the ovarian follicle compared with other available drugs, suggesting that our new drug enhances the efficacy and duration of treatment. It is expected that our new FSH analogue will result in a higher chance of pregnancy in patients who are unresponsive to other drugs.

Effect of varying doses of tamoxifen on ovarian histopathology, serum VEGF, and endothelin 1 levels in ovarian hyperstimulation syndrome: an experimental study

OBJECTIVE

To examine the effects of low-to-high doses of tamoxifen on ovarian histopathology, serum VEGF, and endothelin 1 levels in ovarian hyperstimulation syndrome (OHSS) in an experimental setting.

MATERIALS AND METHODS

A total of 20 female Wistar albino rats, 22 days of age, were randomly divided into four groups. Follicle-stimulating hormone 10 IU was administered subcutaneously in 15 rats on 4 consecutive days, with OHSS induction on day 5 by 30 IU of human chorionic gonadotropin. Group 1 (n=5) comprised 35-day-old control rats, group 2 (n=5) 35-day-old OHSS rats, group 3 (n=5) 27-day-old OHSS rats receiving 1 mg/kg of oral tamoxifen for 7 days, group 4 (n=5) 27-day-old OHSS rats receiving 3 mg/kg of oral tamoxifen for 7 days. All rats were decapitated on day 35. Serum VEGF, endothelin 1, and ovarian follicular reserve were assessed in all rats. Kruskal-Wallis variance analysis and the Mann-Whitney U-test were used for statistical comparisons. A Bonferroni correction was performed to control the inflation of significance, with a significance level set at a P-value of less than 0.025.

RESULTS

Despite higher serum VEGF, endothelin 1, follicular reserve, and angiogenesis and fibrosis of the corpus luteum in the OHSS group compared to controls, these differences were not significant (P>0.025, Mann-Whitney U-test). There was a significant reduction in the ovarian follicular reserve in tamoxifen groups compared to controls (P<0.025, Mann-Whitney U-test), while angiogenesis of the corpus luteum, number of atretic follicles, fibrosis, and serum VEGF were significantly higher in rats receiving tamoxifen (P<0.025, Mann-Whitney U-test). Also, significantly lower follicular reserve and fibrosis were observed among rats in the low-dose tamoxifen group in comparison with rats in the high-dose tamoxifen group (P<0.025, Mann-Whitney U-test). No groups had a significant change in endothelin 1 levels (P>0.025, Mann-Whitney U-test).

CONCLUSION

Tamoxifen 1 g and 3 g resulted in a dose-dependent increase in VEGF and endothelin 1 levels, and ovarian follicle reserves were significantly reduced in our experimental model.

The prevention of ovarian hyperstimulation syndrome

OBJECTIVE

To review the clinical aspects of ovarian hyperstimulation syndrome and provide recommendations on its prevention.

OPTIONS

Preventative measures, early recognition, and prompt systematic supportive care will help avoid poor outcomes.

OUTCOMES

Establish guidelines to assist in the prevention of ovarian hyperstimulation syndrome, early recognition of the condition when it occurs, and provision of appropriate supportive measures in the correct setting.

EVIDENCE

Published literature was retrieved through searches of Medline, Embase, and the Cochrane Library from 2011 to 2013 using appropriate controlled vocabulary ([OHSS] ovarian hyperstimulation syndrome and: agonist IVF, antagonist IVF, metformin, HCG, gonadotropin, coasting, freeze all, agonist trigger, progesterone) and key words (ovarian hyperstimulation syndrome, ovarian stimulation, gonadotropin, human chorionic gonadotropin, prevention). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies published in English. There were no date restrictions. Searches were updated on a regular basis and incorporated in the guideline to February 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). Summary Statements 1. The particular follicle-stimulating hormone formulation used for ovarian stimulation does not affect the incidence of ovarian hyperstimulation syndrome. (I) 2. Coasting may reduce the incidence of severe ovarian hyperstimulation syndrome. (III) 3. Coasting for longer than 3 days reduces in vitro fertilization pregnancy rates. (II-2) 4. The use of either luteinizing hormone or human chorionic gonadotropin for final oocyte maturation does not influence the incidence of ovarian hyperstimulation syndrome. (I) 5. There is no clear published evidence that lowering the human chorionic gonadotropin dose will result in a decrease in the rate of ovarian hyperstimulation syndrome. (III) 6. Cabergoline starting from the day of human chorionic gonadotropin reduces the incidence of ovarian hyperstimulation syndrome in patients at higher risk and does not appear to lower in vitro fertilization pregnancy rates. (II-2) 7. Avoiding pregnancy by freezing all embryos will prevent severe prolonged ovarian hyperstimulation syndrome in patients at high risk. (II-2) 8. Pregnancy rates are not affected when using gonadotropin-releasing hormone (GnRH) agonists in GnRH antagonist protocols for final egg maturation when embryos are frozen by vitrification for later transfer. (II-2) Recommendations 1. The addition of metformin should be considered in patients with polycystic ovarian syndrome who are undergoing in vitro fertilization because it may reduce the incidence of ovarian hyperstimulation syndrome. (I-A) 2. Gonadotropin dosing should be carefully individualized, taking into account the patient's age, body mass, antral follicle count, and previous response to gonadotropins. (II-3B) 3. Cycle cancellation before administration of human chorionic gonadatropin is an effective strategy for the prevention of ovarian hyperstimulation syndrome, but the emotional and financial burden it imposes on patients should be considered before the cycle is cancelled. (III-C) 4. Gonadotropin-releasing hormone (GnRH) antagonist stimulation protocols are recommended in patients at high risk for ovarian hyperstimulation syndrome (OHSS). The risk of severe OHSS in patients on GnRH antagonist protocols who have a very robust ovarian stimulation response can be reduced by using a GnRH agonist as a substitute for human chorionic gonadotropin to trigger final oocyte maturation. (I-B) 5. A gonadotropin-releasing hormone (GnRH) antagonist protocol with a GnRH agonist trigger for final oocyte maturation is recommended for donor oocyte and fertility preservation cycles. (III-C) 6. Albumin or other plasma expanders at the time of egg retrieval are not recommended for the prevention of ovarian hyperstimulation syndrome. (I-E) 7. Elective single embryo transfer is recommended in patients at high risk for ovarian hyperstimulation syndrome. (III-C) 8. Progesterone, rather than human chorionic gonadotropin, should be used for luteal phase support. (I-A) 9. Outpatient culdocentesis should be considered for the prevention of disease progression in severe ovarian hyperstimulation syndrome. (II-2B).

Oocyte number as a predictor for ovarian hyperstimulation syndrome and live birth: an analysis of 256,381 in vitro fertilization cycles

OBJECTIVE

To investigate the association between oocyte number and the rates of ovarian hyperstimulation syndrome (OHSS) and live birth (LB) in fresh autologous in vitro fertilization (IVF) cycles.

DESIGN

Retrospective cohort study.

SETTING

An academic reproductive medicine practice.

PATIENT(S)

We analyzed data from 256,381 IVF cycles using the 2008-2010 Society for Assisted Reproductive Technology national registry. Patients were divided into five groups based on retrieved oocyte number.

MAIN OUTCOME MEASURE(S)

Rates of OHSS and LB were calculated for each group. A generalized estimating equation (GEE) was used to assess differences in OHSS and LB between groups. Receiver operating characteristic (ROC) curves were used to evaluate oocyte number as a predictor of OHSS and LB.

INTERVENTION(S)

None.

RESULT(S)

The LB rate increased up to 15 oocytes, then plateaued (0-5: 17%, 6-10: 31.7%; 11-15: 39.3%; 16-20: 42.7%; 21-25: 43.8%; and >25 oocytes: 41.8%). However, the rate of OHSS became much more clinically significant after 15 oocytes (0-5: 0.09%; 6-10: 0.37%; 11-15: 0.93%; 16-20: 1.67%; 21-25: 3.03%; and >25 oocytes: 6.34%). These trends remained after adjustment with the use of GEE. ROC curves revealed that although oocyte number is not useful in the prediction of LB, 15 retrieved oocytes is the number that best predicts OHSS risk.

CONCLUSION(S)

Retrieval of >15 oocytes significantly increases OHSS risk without improving LB rate in fresh autologous IVF cycles. In general, less aggressive stimulation protocols should be considered, especially in high-responders, to optimize outcomes.

Increased risk of ovarian hyperstimulation syndrome following controlled ovarian hyperstimulation in patients with vascular endothelial growth factor +405 cc genotype

Ovarian hyperstimulation syndrome (OHSS) is a serious complication following controlled ovarian hyperstimulation (COH) for in vitro fertilization. OHSS has a range of clinical features from mild abdominal distention to severe thromboembolic events. Several clinical manifestations of OHSS such as ascites and hemoconcentration can be attributed to increased vascular permeability. Vascular endothelial growth factor (VEGF) and its receptor VEGFR2 have been identified as an important signaling system in mediating this increase. There is considerable genetic variation in the VEGF/R2 signaling system. We present the first study to examine if single nucleotide polymorphisms (SNPs) in the genes encoding the VEGF/R2 signaling system are associated with OHSS following COH. Blood samples from 53 OHSS patients and 100 controls were analyzed for six SNPs of interest. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated by a multivariate logistic regression model. We found an association between the VEGF +405cc genotype and OHSS (OR 3.4, 95% CI 1.01-11.7). This finding requires confirmation from other patient populations.

In vitro fertilisation treatment and factors affecting success

The efficacy of assisted reproductive technologies has improved significantly over the past decades. The main indications for in vitro fertilisation include tubal obstruction, severe male-factor infertility, severe endometriosis, ovulatory dysfunction, diminished ovarian reserve, and infertility of unexplained cause. In vitro fertilisation has also become an effective treatment option for couples wishing to undergo pre-implantation genetic diagnosis or screening, and for those wishing to cryopreserve their oocytes or embryos for preservation of fertility. The management of women in late reproductive age poses a major challenge; the optimum in vitro fertilisation treatment for poor responders remains elusive. The success of in vitro fertilisation treatment can be optimised by taking an individualised, patient-centered approach to controlled ovarian hyperstimulation. Key components involve selection of an appropriate controlled ovarian protocol, close-cycle monitoring, adjustment of gonadotropin dosage to avoid hyper-response, and individualised timing of human chorionic gonadotropin injection. Future directions of assisted reproductive technologies include development of non-invasive embryo selection methods, use of transcriptomics, proteomics, metabolomics, and time-lapse imaging technologies.

GnRH antagonist rescue in high responders at risk for OHSS results in excellent assisted reproduction outcomes

Gonadotrophin-releasing hormone (GnRH) antagonist rescue is performed by replacing a GnRH agonist with a GnRH antagonist in patients with rapidly rising serum oestradiol who are at risk of ovarian hyperstimulation syndrome (OHSS) during stimulation. It results in a rapid reduction in serum oestradiol, allowing for the avoidance of cycle cancellation and the continuation of exogenous gonadotrophin administration. A total of 387 patients who underwent GnRH antagonist rescue for ovarian hyperresponse were compared with 271 patients who did not receive GnRH antagonist rescue and had oestradiol concentrations >4000 pg/ml on the day of human chorionic gonadotrophin (HCG) administration. GnRH antagonist rescue decreased the mean oestradiol concentration by 35% on the first day of use. There was no difference in oocyte maturity (82% versus 83%) or fertilization rate (69% versus 67%) between the antagonist rescue and comparison groups, respectively. The percentage of high-grade embryos on day 3 and the blastocyst development rate were also similar between groups. The live-birth rate was 41.9% in the antagonist rescue group and 36.9% in the comparison group. GnRH antagonist rescue enabled cycle completion with high live-birth rates in patients at risk for OHSS. GnRH antagonist was associated with high oocyte quality, blastocyst development and pregnancy. Gonadotrophin-releasing hormone (GnRH) antagonist rescue is a protocol to reduce the risk of ovarian hyperstimulation syndrome (OHSS) in assisted reproduction treatment. Patients who have a hyperresponse to medication during their treatment cycle have their GnRH agonist discontinued and a GnRH antagonist started in its place. This causes a rapid reduction in oestrogen concentrations and allows for the continuation of stimulation medication. We evaluated the effectiveness of this protocol by comparing patients who had GnRH antagonist rescue against high-responding patients who did not receive GnRH antagonist rescue. GnRH antagonist rescue resulted in a 35% reduction in oestrogen concentration and only a 1.5% cycle cancellation rate. There were no differences in oocyte maturity or fertilization between the two groups. There were no differences in the quality of day-3 and day-5 embryos between the two groups. The live birth rate was 41.9% in the antagonist rescue group and 36.9% in the comparison group. GnRH antagonist rescue reduced serum oestradiol concentrations and enabled cycle completion with high live-birth rates in patients at risk for OHSS. GnRH antagonist was associated with high oocyte quality, blastocyst development and pregnancy.

Predicting and preventing ovarian hyperstimulation syndrome (OHSS): the need for individualized not standardized treatment

Ovarian hyperstimulation syndrome (OHSS) is the most serious complication of controlled ovarian stimulation (COS) as part of assisted reproductive technologies (ART). While the safety and efficacy of ART is well established, physicians should always be aware of the risk of OHSS in patients undergoing COS, as it can be fatal. This article will briefly present the pathophysiology of OHSS, including the key role of vascular endothelial growth factor (VEGF), to provide the foundation for an overview of current techniques for the prevention of OHSS. Risk factors and predictive factors for OHSS will be presented, as recognizing these risk factors and individualizing the COS protocol appropriately is the key to the primary prevention of OHSS, as the benefits and risks of each COS strategy vary among individuals. Individualized COS (iCOS) could effectively eradicate OHSS, and the identification of hormonal, functional and genetic markers of ovarian response will facilitate iCOS. However, if iCOS is not properly applied, various preventive measures can be instituted once COS has begun, including cancelling the cycle, coasting, individualizing the human chorionic gonadotropin trigger dose or using a gonadotropin-releasing hormone (GnRH) agonist (for those using a GnRH antagonist protocol), the use of intravenous fluids at the time of oocyte retrieval, and cryopreserving/vitrifying all embryos for subsequent transfer in an unstimulated cycle. Some of these techniques have been widely adopted, despite the scarcity of data from randomized clinical trials to support their use.

The diagnosis and management of ovarian hyperstimulation syndrome

OBJECTIVE

To review the clinical aspects of ovarian hyperstimulation syndrome and provide recommendations on its diagnosis and clinical management.

OUTCOMES

These guidelines will assist in the early recognition and management of ovarian hyperstimulation. Early recognition and prompt systematic supportive care will help avert poor outcomes.

EVIDENCE

Medline, Embase, and the Cochrane database were searched for relevant articles, using the key words "ovarian hyperstimulation syndrome" and "gonadotropins," and guidelines created by other professional societies were reviewed.

VALUES

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described in that report (Table 1).

RECOMMENDATIONS

1. Once the diagnosis of ovarian hyperstimulation syndrome is made, disease severity should be classified as mild, moderate, severe, or critical. (III-B) 2. The physician prescribing gonadotropins should inform each woman of her personal risk for ovarian hyperstimulation syndrome. (III-A) 3. In areas where patients do not have ready access to physicians familiar with the diagnosis and management of ovarian hyperstimulation syndrome, the physician prescribing gonadotropins should ensure that women are made aware that they should contact a physician or a member of the team within the hospital unit who has relevant experience, should the need arise. (III-B) 4. Outpatient management is recommended for women with mild and moderate ovarian hyperstimulation syndrome. If outpatient management for more severe ovarian hyperstimulation syndrome is to be undertaken, the physician should ensure that the woman is capable of adhering to clinical instructions and that there is a system in place to assess her status every 1 to 2 days. (III-A) 5. Paracentesis should be performed in admitted patients with tense ascites to alleviate their discomfort. (II-2B) 6. Outpatient culdocentesis should be considered for the prevention of disease progression in moderate or severe ovarian hyperstimulation syndrome. (II-2B) 7. Women with severe and critical ovarian hyperstimulation syndrome should be admitted to hospital for intravenous hydration and observation. (III-A) 8. Intravenous hydration should be initiated with a crystalloid solution to prevent hemoconcentration and provide adequate end-organ perfusion. If end-organ perfusion is not maintained with a crystalloid solution, an alternate colloid solution should be administered. (II-2B) 9. Pain relief in admitted patients should be managed with acetaminophen and/or opioid analgesics. (III-B) Non-steroidal anti-inflammatory drugs with antiplatelet properties should not be used. (III-B) 10. Women with severe ovarian hyperstimulation syndrome should be considered for treatment with prophylactic doses of anticoagulants. (II-2B) 11. Critical ovarian hyperstimulation syndrome should be managed by a multidisciplinary team, according to the end organ affected. (III-C).

Assessing the risk of ovarian hyperstimulation syndrome in egg donation: implications for human embryonic stem cell research

Stem cell research has important implications for medicine. The source of stem cells influences their therapeutic potential, with stem cells derived from early-stage embryos remaining the most versatile. Somatic cell nuclear transfer (SCNT), a source of embryonic stem cells, allows for understandings about disease development and, more importantly, the ability to yield embryonic stem cell lines that are genetically matched to the somatic cell donor. However, SCNT requires women to donate eggs, which involves injection of ovulation-inducing hormones and egg retrieval through laparoscopy or transvaginal needle aspiration. Risks from this procedure are fiercely debated, most notably risk of ovarian hyperstimulation syndrome (OHSS). This review examines risk of OHSS resulting from oocyte donation. We conclude that risk posed by OHSS in egg donation is not significant enough to warrant undue concern, and much of this can be eliminated when proper precautions are taken. This bears relevance to the future of stem cell research policymaking.

[Ovarian hyperstimulation syndrome: pathophysiology, risk factors, prevention, diagnosis and treatment]

The ovarian hyperstimulation syndrome is a major complication of ovulation induction for in vitro fertilization, with severe morbidity and possible mortality. Whereas its pathophysiology remains ill-established, the VEGF may play a key role as well as coagulation disturbances. Risk factors for severe OHSS may be related to patients characteristics or to the management of the ovarian stimulation. Two types of OHSS are usually distinguished: the early OHSS, immediately following the ovulation triggering and a later and more severe one, occurring in case of pregnancy. As no etiologic treatment is available, the therapeutic management of OHSS should focus on its related-complications. Thrombotic complications that can occur in venous or arterial vessels represent the major risk of OHSS, possibly conducting to myocardial infarction and cerebrovascular accidents. Once the OHSS is diagnosed, prevention of thrombotic accidents remains the major issue.

Influence of follicle-stimulating hormone receptor (FSHR) Ser680Asn polymorphism on ovarian function and in-vitro fertilization outcome: a meta-analysis

BACKGROUND

A common follicle-stimulating hormone (FSH) receptor (or FSHR) polymorphism Ser680Asn (rs6166) was found to be associated with altered ovarian response in women undergoing in-vitro fertilization. To further investigate such an association, a meta-analysis was conducted.

METHODS

A PubMed literature search was conducted to identify all cohort studies investigating such a relationship. The following parameters-basal FSH levels, total FSH doses, oocytes retrieved, and pregnancy rates-were used to evaluate the ovarian function, its response to exogenous FSH and in-vitro fertilization and intracytoplasmic sperm injection outcome.

RESULTS

A total of 1421 cases were collected from eight studies. Of them, a significantly lower basal FSH level was observed in patients harboring Asn/Asn (NN) genotype than those carrying the Ser/Ser (SS) genotype both in Asian (WMD: -2.57 mIU/ml, 95% CI: -2.96 to -2.19, P<0.0001) and Caucasian retrospective groups (WMD: -1.86 mIU/ml, 95%CI: -2.07 to -1.66, P<0.0001) with no heterogeneity. Moreover, carriers of the SS tended to require greater FSH doses than NN (WMD: -268.82IU, 95% CI: -561.28 to 23.63, P=0.07). Other parameters, such as oocytes retrieved and pregnancy rate, were not significantly different between the groups.

CONCLUSION

Carriers of the SS variant have slightly higher basal FSH levels, tending to require higher doses of exogenous FSH for stimulation.

Ovarian hyperstimulation syndrome in a patient treated with tamoxifen for breast cancer

OBJECTIVE

To report the management of a rare case of ovarian hyperstimulation syndrome (OHSS) induced by tamoxifen therapy for breast cancer in a 50-year-old woman.

DESIGN

Case report.

SETTING

Gynecology outpatient department of a university hospital.

PATIENT(S)

A 50-year-old premenopausal patient with a history of breast cancer was prescribed adjuvant treatment with tamoxifen.

INTERVENTION(S)

Temporary discontinuation of tamoxifen therapy resolved symptoms, but resumption of tamoxifen caused a recurrence of symptoms. Surgical bilateral salpingo-oophrectomy was therefore performed.

MAIN OUTCOME MEASURE(S)

Resolution of symptoms of OHSS.

RESULT(S)

Bilateral salpingo-oophrectomy rendered the patient postmenopausal and enabled the commencement of the aromatase inhibitor anastrozole as an alternative adjuvant therapy for breast cancer.

CONCLUSION(S)

Tamoxifen-induced OHSS is rare. Furthermore, OHSS is very rare in the older female. OHSS usually resolves with temporary discontinuation of tamoxifen, however, the recurrence of symptoms when resuming tamoxifen is better treated with bilateral salpingo-oophorectomy to enable adjuvant treatment with anastrazole.