Life-threatening complications among women with severe ovarian hyperstimulation syndrome

Effect of aromatase inhibitors for preventing ovarian hyperstimulation syndrome in infertile patients undergoing in vitro fertilization: a systematic review and meta-analysis

PURPOSE

To summarize the findings of relevant randomized controlled trials (RCTs) and conduct a meta-analysis to investigate the potential effect of aromatase inhibitors on preventing moderate to severe ovarian hyperstimulation syndrome (OHSS) in infertile women undergoing in vitro fertilization (IVF).

METHODS

We searched for relevant RCTs in electronic databases, including MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov (from inception to August 2023). In addition, we manually searched the related reviews and reference lists of included studies for further relevant studies. We included RCTs where aromatase inhibitors prescribed either during controlled ovarian stimulation (COS) or in early luteal phase. The meta-analysis was performed using RevMan 5.4.1 software. The primary outcome was the incidence of moderate to severe OHSS. A descriptive analysis was conducted in cases where a meta-analysis was not feasible due to heterogeneity or lack of comparable data.

RESULTS

2858 records were retrieved and 12 RCTs were finally included. Letrozole was administered in the treatment group during COS in seven RCTs, whereas in the early luteal phase in five RCTs. Compared with the control group, the risk of moderate to severe OHSS significantly reduced by 55% in the letrozole group (RR 0.45, 95% CI 0.32 to 0.64, I2 = 0%, 5 RCTs, 494 patients). Moreover, serum estradiol (E2) levels on hCG trigger day significantly decreased with the administration of letrozole during COS (MD -847.23, 95% CI -1398.00 to -296.47, I2 = 93%, 5 RCTs, 374 patients). And serum E2 levels on the 4th, 5th and 7th to 10th day after hCG trigger were also significantly lower than those in the control group when letrozole was administered in the early luteal phase.

CONCLUSIONS

Patients with high risk of OHSS probably benefit from letrozole, which has been revealed to reduce the incidence of moderate to severe OHSS by this systematic review. However, the very limited number of participants and the quality of the included studies does not allow to recommend letrozole for the prevention of severe OHSS.

Egg donor self-reports of ovarian hyperstimulation syndrome: severity by trigger type, oocytes retrieved, and prior history

PURPOSE

To evaluate self-reported survey data provided by US oocyte donors on their experiences with ovarian hyperstimulation syndrome and possible correlations between OHSS severity and number of oocytes retrieved, trigger type, and prior OHSS history.

METHODS

An 85-question retrospective survey was administered online. Survey questions included demographic information, reasons for donating, immediate per-cycle experiences and outcomes, perceptions of informed consent, and perceived impact of donation on long-term health. Quantitative Data for this study was collected between February 2019 and September 2020 via Qualtrics^XM (January 2019), an online survey platform. Follow-up interviews were also conducted. Participants were recruited via fertility clinics, egg donation agencies, and online forum. The research was approved by the University of California, San Francisco Institutional Review Board (#14-14765).

RESULTS

Of 420 initiated US oocyte donor online surveys, 289 (68%) respondents provided detailed information on per cycle experiences with ovarian hyperstimulation syndrome, number of oocytes retrieved, and trigger type over a total of 801 cycles. On cycles where donors reported receiving GnRH agonist triggers (n = 337), they reported milder OHSS compared to cycles with hCG or dual triggers. Among donors undergoing multiple retrieval cycles, the severity of OHSS in second cycles was strongly associated with OHSS severity in first cycles.

CONCLUSION

Self-reported OHSS in oocyte donors is lower in GnRH antagonist stimulation protocols combined with GnRHa trigger and in cycles where donors reported fewer than 30 oocytes retrieved. Donors who reported severe OHSS on a prior cycle were significantly more likely to experience severe OHSS on a subsequent cycle.

Chronic kidney disease, female infertility, and medically assisted reproduction: a best practice position statement by the Kidney and Pregnancy Group of the Italian Society of Nephrology

Fertility is known to be impaired more frequently in patients with chronic kidney disease than in the general population. A significant proportion of chronic kidney disease patients may therefore need Medically Assisted Reproduction. The paucity of information about medically assisted reproduction for chronic kidney disease patients complicates counselling for both nephrologists and gynaecologists, specifically for patients with advanced chronic kidney disease and those on dialysis or with a transplanted kidney. It is in this context that the Project Group on Kidney and Pregnancy of the Italian Society of Nephrology has drawn up these best practice guidelines, merging a literature review, nephrology expertise and the experience of obstetricians and gynaecologists involved in medically assisted reproduction. Although all medically assisted reproduction techniques can be used for chronic kidney disease patients, caution is warranted. Inducing a twin pregnancy should be avoided; the risk of bleeding, thrombosis and infection should be considered, especially in some categories of patients. In most cases, controlled ovarian stimulation is needed to obtain an adequate number of oocytes for medically assisted reproduction. Women with chronic kidney disease are at high risk of kidney damage in case of severe ovarian hyperstimulation syndrome, and great caution should be exercised so that it is avoided. The higher risks associated with the hypertensive disorders of pregnancy, and the consequent risk of chronic kidney disease progression, should likewise be considered if egg donation is chosen. Oocyte cryopreservation should be considered for patients with autoimmune diseases who need cytotoxic treatment. In summary, medically assisted reproduction is an option for chronic kidney disease patients, but the study group strongly advises extensive personalised counselling with a multidisciplinary healthcare team and close monitoring during the chosen medically assisted reproduction procedure and throughout the subsequent pregnancy.

Venous Thromboembolism Associated with Assisted Reproductive Technology: A Systematic Review and Meta-analysis

BACKGROUND

 Hormonal exposure leads to an increased risk of venous thromboembolism (VTE) but the risk of VTE associated with assisted reproductive technology (ART) is not clearly determined.

METHODS

 We searched in PubMed, EMBASE, Web of Science, and the Cochrane Library databases and identified all relevant articles published up to February 1, 2021. The primary objective was to determine the frequency of VTE associated with ART. Secondary objectives were to determine (1) the risk of VTE associated with ART as compared to pregnancy without ART; (2) the risk of VTE associated with ovarian hyperstimulation syndrome (OHSS); and (3) to determine potential risk factors of VTE related to ART.

RESULTS

 Fourteen studies were included. The overall frequency of VTE associated with ART was 0.23% (95% confidence interval [CI]: 0.07-0.46). Women undergoing ART had a two- to threefold increased risk of VTE as compared to spontaneous pregnancy (relative risk [RR]: 2.66; 95% CI: 1.60-4.43). The overall frequency of VTE specifically related to OHSS was <0.001%. The risk of VTE after ART complicated by OHSS, as compared to ART without OHSS, was higher but not statistically significant (RR: 14.83; 95% CI: 0.86-255.62). Risk factors of VTE associated with ART were in vitro fertilization procedure (RR, odds ratio [OR], and hazard ratio varying from 1.77, 95% CI: 1.41-2.23 to 4.99, 95% CI: 1.24-20.05), hyperhomocysteinemia (OR: 15.2; 95% CI: 2.0-115.0), polycystic ovarian syndrome (PCOS) (RR: 4.8; 95% CI: 1.7-13.4), successful ART leading to pregnancy (OR: 13.94; 95% CI: 1.41-137.45).

CONCLUSION

 Further large prospective studies on risk factors of VTE in women undergoing ART are needed in order to optimize thromboprophylaxis in this context.

Intrafollicular fluid metabolic abnormalities in relation to ovarian hyperstimulation syndrome: Follicular fluid metabolomics via gas chromatography-mass spectrometry

INTRODUCTION

Ovarian hyperstimulation syndrome (OHSS) is the most serious iatrogenic complication of ovulation stimulation during assisted reproductive technology. The main objective of this study was to investigate intrafollicular fluid metabolic change profiles of OHSS in non-ovarian etiologic infertility women (CON) and polycystic ovarian syndrome patients (PCOS).

METHODS

87 infertile women were divided into four subgroups: CON-Norm (CON with normal ovarian response), CON-OHSS (CON with OHSS), PCOS-Norm (PCOS with normal ovarian response), and PCOS-OHSS (PCOS with OHSS). The intrafollicular fluid metabolic profiles were analyzed with gas chromatography-mass spectrometry. The multivariable-adjusted conditional logistic regression was applied to assess the association of metabolites with OHSS risk.

RESULTS

We identified 17 and 3 metabolites that related to OHSS risk in CON and PCOS, respectively. 13 OHSS risk-related metabolites in CON were unsaturated fatty acids, 8 of which were also the significantly altered metabolites between all PCOS and CON-Norm.

CONCLUSION

Our study may shed light on the role of intrafollicular fluid metabolic abnormalities in the pathophysiology of OHSS. The findings suggested that there might be some metabolic heterogeneities underlying the development of OHSS in CON and PCOS women and indicated possible shared etiological factors in the development of PCOS and OHSS.

Risk of thrombosis in women with cancer undergoing controlled ovarian hyperstimulation for fertility preservation

PURPOSE

The study aims to evaluate the risk factors and incidence of thromboembolic events among adult women with cancer who underwent controlled ovarian hyperstimulation (COH) for fertility preservation.

METHODS

Retrospective, descriptive cohort analysis of patient demographics, medical history, cancer type/treatment, laboratory values, thrombosis within 6 months of COH.

RESULTS

4 of 127 study participants experienced a venous thromboembolic event within 6 months of COH. The median time between oocyte aspiration and the event was 0.25 years (range = 0.10-0.50). The average age at time of event was 25.3 years (SD = 5.3). Three of four thrombotic patients had ovarian cancer, one had breast cancer. All had received surgery and chemotherapy for treatment. All underwent an antagonist cycle ovarian stimulation protocol - none developed ovarian hyperstimulation syndrome. The average anti-mullerian hormone level at the time of hyperstimulation in the thrombosis group was 1.6 (SD = 1.3), compared to 3.6 in the non-thrombosis group. The average max estradiol level reached during ovarian stimulation was 1281.3 (SD = 665.3) in the thrombosis group and 1839.1 (SD = 1513.9) in the non-thrombosis group. Thromboembolic events were not directly associated with mortality.

CONCLUSIONS

Within this small descriptive study, the incidence of thromboembolic events in women with cancer undergoing COH for fertility preservation is high. Cancer may play a greater role than COH in thrombosis risk. Ovarian cancer patients who undergo ovarian stimulation may have an increased risk compared to other cancer types. These findings may inform future, prospective studies to determine the role of thromboprophylaxis.

The ART of Thromboprophylaxis in the Prevention of Gestational Venous Thromboembolism

Assisted reproductive techniques (ART) allow infertile couples to conceive. Use of hormones to obtain a controlled ovarian stimulation and an adequate growth of the endometrium preparatory for embryo implantation are not riskless. Among others, thrombotic events can occur during the ovulation induction or pregnancy following ART. As the number of women approaching ART to conceive is steadily increasing, the issue of thrombotic risk in this setting is relevant. Data on the weight of each risk factor and on potential benefit of thromboprophylaxis are largely lacking. In this review, we discuss risk of venous thromboembolism during pregnancy following ART, with a focus on general (i.e.: age, body mass index, thrombophilia, bed rest, transfusions) and ART-specific (i.e., polycystic ovarian syndrome, ovarian hyperstimulation syndrome) risk factors. We also attempt to provide some suggestions to guide clinical practice, based on available data and studies performed outside ART.

Emergency department utilization for ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a rare, but serious, risk of assisted reproductive technologies. In severe cases, patients may present to the emergency department (ED) for assessment, treatment of related complications, and even in-patient admission. Significant effort has been made to reduce the incidence and complications of OHSS; however, it is unknown if these strategies have decreased patient presentation for treatment in the ED.

PURPOSE

To assess ED utilization for OHSS over time and to examine admission rates, patient demographics, and charges.

METHODS

Retrospective longitudinal study utilizing data from the Nationwide Emergency Department Sample Database and the National ART Surveillance System. All ED visits between 2006 and 2016 with an ICD-9 or -10 diagnosis of OHSS were included. Demographics including age, geographic location, and income quartile and alternative diagnoses, admission rates, overall charges, and number of stimulation cycles annually were assessed.

RESULTS

The number of ovarian stimulation cycles steadily increased from 2006 (n = 110,183) to 2016 (n = 157,721), while the number of OHSS-related ED visits remained relatively stable (APC 2.08, p = 0.14). Admission rates for OHSS decreased from 52.7% in 2006 to 33.1% in 2016 (APC -4.43%, p < 0.01). The average charge for OHSS-related ED visits almost doubled from 2006 to 2016 (APC 8.53, p < 0.01) and was significantly higher than charges for non-OHSS-related visits for age-matched controls (p < 0.01).

CONCLUSION

Despite an increase in total stimulation cycles, there was no significant change in the estimated number of patients presenting to the ED; however, admission rates significantly declined. These observations suggest a possible shift in the severity and/or management of OHSS during the study period.

Association between hospital treatment volume and major complications in ovarian hyperstimulation syndrome

OBJECTIVE

An inverse relationship between hospital volume and adverse patient outcomes has been established for many conditions, but has not yet been examined in ovarian hyperstimulation syndrome (OHSS). Given the rarity of severe OHSS, but potential for high morbidity, this study aimed to elucidate the effect of hospital volume on inpatient OHSS-related complications.

METHODS

This is a retrospective observational study querying the National Inpatient Sample, 1/2001-12/2011. Study population was 11,878 patients with OHSS treated at 735 hospitals. Annualized hospital OHSS treatment volume was grouped as: low-volume (1 case/year), mid-volume (>1 but < 3.5 cases/year), and high-volume (≥3.5 cases/year). Main outcome measure was major complication rates stratified by hospital treatment volume, assessed by multinomial regression and binary logistic regression models.

RESULTS

A total of 2,415 (20.3%) patients were treated at low-volume centers, 5,023 (42.3%) at mid-volume centers, and 4,440 (37.4%) at high-volume centers. Patients treated at high-volume centers were more likely to be older and less comorbid with higher incomes and lower body mass index (P < 0.05). High-volume hospitals were more likely to be urban-teaching centers with large bed capacity (P < 0.001). Overall, 1,624 (13.7%) patients experienced a major complication during hospitalization. Patients treated at high-volume hospitals had lower rates of major complications (high: 11.0%, mid: 15.2%, low: 15.6%, P < 0.001). On multivariable analysis, treatment at high-volume hospitals was independently associated with a nearly 20% lower rate of major complications (odds ratio 0.82, 95% confidence interval 0.70-0.97, P = 0.021).

CONCLUSION

Our study suggests that higher hospital treatment volume for OHSS may be associated with improved outcomes.

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.

Spontaneous ovarian hyperstimulation syndrome in a nonpregnant female patient: a case report and literature review

Spontaneous ovarian hyperstimulation syndrome (sOHSS) usually occurs in patients with a spontaneous ovulation cycle, especially in those with multiple pregnancies combined with hypothyroidism and polycystic ovary syndrome. sOHSS rarely occurs in women who are not pregnant. A 23-year-old woman with obvious abdominal distension visited our hospital. The patient was not pregnant and had not undergone controlled superovulation. Apart from abdominal distension, the patient denied any symptom of obvious incentives, abdominal pain, abnormal vaginal bleeding, or drainage. Biochemical analysis showed a high carbohydrate antigen-125 level and low total protein and albumin levels. Abdominal ultrasound and computed tomography showed a large amount of ascites and cystic uneven masses with an irregular shape in the area of the ovaries and fallopian tubes. Post-surgical histopathology indicated the diagnosis of sOHSS. Wedge resection of both ovaries was performed. Symptomatic treatment was further performed and the patient recovered well. Our findings indicate that sOHSS can occur in women who are not pregnant. Additionally, besides the follicle-stimulating hormone receptor gene mutation hypothesis, the pathogenesis of sOHSS should be further studied.

Transient receptor potential melastatin 2 ion channel activity in ovarian hyperstimulation syndrome physiopathology

Background/aim

Ovarian hyperstimulation syndrome (OHSS) is a complication of ovarian stimulation with increased vascular endothelial growth factor (VEGF) and vascular permeability in the ovarian tissue. Transient receptor potential melastatin 2 (TRPM2) is known to be associated with angiogenesis and vascular permeability. In this experimental study, we aimed to investigate the activity of TRPM2 in the development of OHSS.

Materials and methods

Fourteen immature female rats were divided into two groups. Group 1 was the control group, and Group 2 was the OHSS group that was exposed to 10 IU of subcutaneous application of FSH for four days and 30 IU of human chorionic gonadotropin (hCG) on the 5th day. At the end of the experiment, the ovaries were removed. The right ovarian tissues were stored in 10% formol for histopathological and immunohistochemical examination. The left ovarian tissues were stored at –80 °C for biochemical examinations. VEGF, tumor necrosis factor-alpha (TNF‐α) and malondialdehyde (MDA) levels were measured in the ovarian tissue. Congestion, edema, apoptosis and TRPM2 immunoreactivity were evaluated.

Results

There was a significant increase in ovarian weight in the OHSS group compared to the control group. There was a significant increase in congestion, edema, apoptosis and TRPM2 immunoreactivity in the OHSS group. A significant increase in tissue levels of VEGF, TNF‐α and MDA was also found in the OHSS group compared to the control group.

Conclusion

As a result of our experiment, it was found that increased TRPM2 immunoreactivity on hyperstimulated rat ovary may be the reason or result of edema and congestion. Further studies are needed to discuss our results.

Assessing the Usefulness of Severity Markers in Women with Ovarian Hyperstimulation Syndrome

The present study aims to assess the usefulness of severity markers in women with ovarian hyperstimulation syndrome (OHSS). An observational study was designed including 76 women with varying degrees of severity of OHSS. Clinical history, physical examination, laboratory tests, and ultrasound measurement of the ovarian size and ascites index were carried out in all patients. Intra-abdominal pressure (IAP) was measured using an intravesical Foley Manometer catheter. Ascites index and ovarian volume increased progressively being highest in the most severe stage of OHSS. The median IAP in mild OHSS was found to be lower than that in the moderate and severe OHSS (4.0 mm, 12 mm, and 16.0 mm, respectively). Critical cases of OHSS presented the highest IAP (25.0 mm). IAP did not reach the level of intra-abdominal hypertension in mild OHSS, whereas moderate and severe OHSS was associated with intra-abdominal hypertension grade I and grade II-III, respectively. Values of IAP in critical OHSS were found similar to those observed in abdominal compartment syndrome patients. The IAP showed a strong positive correlation with ovarian volume and ascites index. The reduction of IAP after paracentesis was greater among critical OHSS patients. The ovarian volume and the level of intra-abdominal hypertension are related to the severity of OHSS and are of particular importance in the initialization of the syndrome. Ascites index is simple and convenient and can serve as an indirect marker of the abdominal reserve volume. In conjunction with clinical and laboratory data, ascites index and IAP values might be indicators for paracentesis.

Rescue In Vitro Maturation in Polycystic Ovarian Syndrome Patients Undergoing In Vitro Fertilization Treatment who Overrespond or Underrespond to Ovarian Stimulation: Is It A Viable Option? A Case Series Study

Background

This study intends to present the role of rescue in vitro maturation (IVM) in polycystic ovarian syn- drome (PCOS) patients undergoing in vitro fertilization (IVF) treatment who have inappropriate responses to ovarian stimulation.

Materials and Methods

This was a retrospective case series study of five PCOS patients undergoing IVF treatment considered for cycle cancellation due to increased risk of ovarian hyperstimulation syndrome (OHSS) as group A or poor response to ovarian stimulation as group B. Patients in group A had high oestradiol levels and recruitment of high numbers of small/intermediate sized follicles that did not meet the criteria for human chorionic gonadotropin (hCG) triggering. Patients in group B responded inadequately to hormonal stimulation despite high gonadotropin dosage. Treatment was changed to rescue IVM cycles after the patients provided consent.

Results

In group A, three IVF patients deemed to have high chances of developing OHSS as evidenced by high oestradiol levels were converted to IVM. A total of the 58/68 oocytes retrieved were mature or matured in vitro. There were 26 cleaving embryos obtained. Two patients had live births and one patient suffered a miscarriage. In group B, rescue IVM was implemented in two patients due to poor ovarian response (POR). A total of 22/26 oocytes retrieved were mature or matured in vitro. There were 13 cleaving embryos obtained. One patient had a live birth, whilst the other suffered a miscarriage.

Conclusion

Rescue IVM could be a viable option in PCOS patients undergoing IVF treatment who are unable to safely meet the criteria for hCG triggering due to overresponse to ovarian stimulation or ovarian resistance to high doses of stimulation. Conversion to IVM can still result in reasonable oocyte retrieval and lead to clinical pregnancy and live births without the risks of OHSS.

Ovarian hyperstimulation syndrome: A review for emergency clinicians

INTRODUCTION

A great deal of literature has recently evaluated the prevention and management of ovarian hyperstimulation syndrome (OHSS) in the outpatient setting, but there remains a dearth of research evaluating OHSS in the emergency department (ED) and its management.

OBJECTIVE

This narrative review evaluates the underlying pathophysiology and clinical manifestations of OHSS and discusses approaches to patient care in the ED based on current literature.

DISCUSSION

OHSS is an iatrogenic complication caused by an excessive response to controlled ovarian stimulation during assisted reproductive cycles (ART). OHSS complicates up to 30% of ART cycles, and many of these patients seek initial care in the ED. Risk factors for the development of OHSS include age < 35, history of polycystic ovarian syndrome or previous OHSS, and pregnancy. Emergency physicians will be faced with several complications including ascites, abdominal compartment syndrome, renal dysfunction, acute respiratory distress syndrome, thromboembolic disease, and hemodynamic instability. Critical patients should be evaluated in the resuscitation bay, and consultation with the primary obstetrics/gynecology team is needed, which improves patient outcomes. This review provides several guiding principles for management of OHSS and associated complications.

CONCLUSIONS

OHSS occurs in up to 30% of IVF cycles and carries a high morbidity. Effective care of the OHSS patient begins with early diagnosis while evaluating for other diseases and complications. Understanding these complications and an approach to the management of OHSS is essential to optimizing patient care.