Interventions to prevent or reduce the incidence and severity of ovarian hyperstimulation syndrome: a systematic umbrella review of the best clinical evidence

Ovarian hyperstimulation syndrome (OHSS) is a potentially life-threating iatrogenic complication of the early luteal phase and/or early pregnancy after in vitro fertilization (IVF) treatment. The aim of the current study was to identify the most effective methods for preventing of and reducing the incidence and severity of OHSS in IVF patients. A systematic review of systematic reviews of randomized controlled trials (RCTs) with meta-analysis was used to assess each potential intervention (PROSPERO website, CRD 268626) and only studies with the highest quality were included in the qualitative analysis. Primary outcomes included prevention and reduction of OHSS incidence and severity. Secondary outcomes were maternal death, incidence of hospital admission, days of hospitalization, and reproductive outcomes, such as incidence of live-births, clinical pregnancies, pregnancy rate, ongoing pregnancy, miscarriages, and oocytes retrieved. A total of specific interventions related to OHSS were analyzed in 28 systematic reviews of RCTs with meta-analyses. The quality assessment of the included studies was high, moderate, and low for 23, 2, and 3 studies, respectively. The certainty of evidence (CoE) for interventions was reported for 37 specific situations/populations and resulted high, moderate, and low-to-very low for one, 5, and 26 cases, respectively, while it was not reported in 5 cases. Considering the effective interventions without deleterious reproductive effects, GnRH-ant co-treatment (36 RCTs; OR 0.61, 95% C 0.51 to 0.72, n = 7,944; I² = 31%) and GnRH agonist triggering (8 RCTs; OR 0.15, 95% CI 0.05 to 0.47, n = 989; I² = 42%) emerged as the most effective interventions for preventing OHSS with a moderate CoE, even though elective embryo cryopreservation exhibited a low CoE. Furthermore, the use of mild ovarian stimulation (9 RCTs; RR 0.26, CI 0.14 to 0.49, n = 1,925; I² = 0%), and dopaminergic agonists (10 RCTs; OR 0.32, 95% CI 0.23 to 0.44, n = 1,202; I² = 13%) coadministration proved effective and safe with a moderate CoE. In conclusion, the current study demonstrates that only a few interventions currently can be considered effective to reduce the incidence of OHSS and its severity with high/moderate CoE despite the numerous published studies on the topic. Further well-designed RCTs are needed, particularly for GnRH-a down-regulated IVF cycles.

Comparison of bromocriptine and hydroxyethyl starch in the prevention of ovarian hyperstimulation syndrome

OBJECTIVE

To evaluate the effectiveness of bromocriptine for prevention of ovarian hyperstimulation syndrome (OHSS).

METHODS

The retrospective study included women at risk of OHSS who were receiving gonadotropin-releasing hormone antagonist protocols, including 52 women given 2.5 mg bromocriptine by rectal insertion, 52 women given 500 ml intravenous hydroxyethyl starch (HES), and 40 women who received no intervention. Treatments were administered daily for 5 days beginning on the day of oocyte retrieval. Baseline information and data related to OHSS were compared.

RESULTS

No significant differences were found among groups in estradiol concentration on the day of trigger or in number of retrieved oocytes. Incidence of mild OHSS was not significantly different among groups, respectively 13.5%, 15.4%, and 17.5% (P > 0.05). The incidence of moderate to severe OHSS was significantly lower in the bromocriptine and HES groups compared with the control group, respectively 7.7%, 5.8%, and 22.5% (P < 0.05). D-dimer levels were significantly lower in the bromocriptine and HES groups compared with the control group on Day 5 after oocyte retrieval (P < 0.05). No differences in liver or renal function were found in the three groups.

CONCLUSION

Bromocriptine was apparently as effective as intravenous HES in patients with high risk of OHSS.

Risk of Higher Blood Pressure in 3 to 6 Years Old Singleton Born From OHSS Patients Undergone With Fresh IVF/ICSI

BACKGROUND

A large registry-based study found the increasing disorders of cardiovascular and metabolism in IVF children but underlying mechanism is still unknown. Few studies have investigated any association between OHSS and cardiovascular or metabolic function in subsequent children.

OBJECTIVE

To evaluate the effect of ovarian hyperstimulation syndrome (OHSS) on blood pressure of singletons after in vitro fertilization (IVF) with or without intracytoplasmic sperm injection (ICSI).

STUDY DESIGN

The singlet-center corhort study included 1780 singletons born with IVF/ICSI and 83 spontaneously conceived children from 2003 to 2014. Follow-up has lasted more than 10 years, and is still ongoing. This study analyzed data from follow-up surveys at 3 to 6 years of age.

PARTICIPANTS SETTING AND METHODS

We recruited 83 children (Group E) spontaneously conceived (SC) as control group and 1780 children born with IVF/ICSI including 126 children born to OHSS-fresh embryo transfer (ET) women (Group A), 1069 children born to non OHSS-ET women (Group B), 98 children conceived by women who developed into moderate or severe OHSS after oocyte retrieval and selected the frozen-thawed embryo transfer (FET) (Group C), 487 children conceived with non OHSS-FET (Group D). We evaluated cardiometabolic function, assessed BP in mmHg, heart rate, anthropometrics, and metabolic index including glucose, serum lipid (triglyceride, total cholesterol, low density lipoprotein, high density lipoprotein), thyroid function, of those children. The BP and heart rate were measured twice on the same day. We applied several multiple regression analyses to investigate the effect of OHSS in the early pregnancy.

MAIN FINDINGS

By the single factor analysis, the SBP and DBP in the SC group (SBP: 99.84 ± 8.9; DBP: 55.27 ± 8.8) were significantly lower than OHSS-ET group's, while the blood pressure was similar between the SC group and other three ART groups. Children had higher BP in the OHSS-ET group (SBP: 101.93 ± 8.17; DBP: 58.75 ± 8.48) than in the non OHSS-ET (SBP: 99.49 ± 8.91; DBP: 56.55 ± 8.02) or OHSS-FET group (SBP: 99.38 ± 8.17; DBP: 55.72 ± 7.94). After using multiple regression analysis to adjust current, early life, parental and ART characteristics, the differences in the SBP and DBP (B (95% confidence interval)) between OHSS-ET and non OHSS-ET remained significant (SBP: 3.193 (0.549 to 2.301); DBP: 3.440 (0.611 to 2.333)). And the BP showed no significant difference complementarily when compared non OHSS-FET group with non OHSS-ET group. In addition, the anthropometrics, fast glucose, serum lipid, and thyroid index did not differ among the ART groups.

PRINCIPAL CONCLUSIONS

OHSS might play an independent key role on offspring's BP even cardiovascular function. Electing frozen-thawed embryo transfer for high risk of OHSS population may reduce the risk of the high BP trend.

WIDER IMPLICATIONS OF THE FINDINGS

It is a large sample study to investigate the effect of OHSS on offspring's health. These findings provide a clinic evidence of the impact of early environment (embryo even oocyte stage) on the offspring's cardiovascular health. Our study emphasis the importance of the accuracy of IVF clinic strategy and preventing the OHSS after fresh embryo transfer.

Severe Ovarian Hyperstimulation Syndrome in a Woman With Breast Cancer Under Letrozole Triggered With GnRH Agonist: A Case Report and Review of the Literature

We report a rare case of ovarian hyperstimulation syndrome (OHSS) in a 28-year-old woman with breast cancer and with a history of polycystic ovary syndrome (PCOS) despite treatment with letrozole and gonadotropin-releasing hormone agonist (GnRH-a) triggering in a GnRH antagonist (GnRH-ant) protocol without the administration of any human chorionic gonadotropin (hCG) for luteal-phase support. The patient, who underwent controlled ovarian syndrome (COS)-oocyte cryopreservation before chemotherapy, required hospitalization. Complete recovery was achieved after treatment with volume expanders, human albumin, and cabergoline. Based on our case and literature review, it is possible to establish that estradiol (E₂) modulation with letrozole and GnRH-a triggering does not eliminate the risk of OHSS. Furthermore, it is advisable to postpone GnRH-a depot to minimize the risk of OHSS after the suspension of letrozole, following menstruation or at least 7–8 days after triggering. It would be desirable to identify high-risk patients, also on a genetic basis, in order to avoid delays in oncologic treatments that could strongly impact life expectancy.

Dopamine agonists for preventing ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a potentially serious complication of ovarian stimulation in assisted reproduction technology (ART). It is characterised by enlarged ovaries and an acute fluid shift from the intravascular space to the third space, resulting in bloating, increased risk of venous thromboembolism, and decreased organ perfusion. Most cases are mild, but forms of moderate or severe OHSS appear in 3% to 8% of in vitro fertilisation (IVF) cycles. Dopamine agonists were introduced as a secondary prevention intervention for OHSS in women at high risk of OHSS undergoing ART treatment.  OBJECTIVES: To assess the effectiveness and safety of dopamine agonists in preventing OHSS in women at high risk of developing OHSS when undergoing ART treatment.

SEARCH METHODS

We searched the following databases from inception to 4 May 2020: Cochrane Gynaecology and Fertility Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, and PsycINFO for randomised controlled trials (RCTs) assessing the effect of dopamine agonists on OHSS rates. We also handsearched reference lists and grey literature.

SELECTION CRITERIA

We considered RCTs for inclusion that compared dopamine agonists with placebo/no intervention or another intervention for preventing OHSS in ART. Primary outcome measures were incidence of moderate or severe OHSS and live birth rate. Secondary outcomes were rates of clinical pregnancy, multiple pregnancy, miscarriage, and adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles, abstracts, and full texts of publications; selected studies; extracted data; and assessed risk of bias. We resolved disagreements  by consensus. We reported pooled results as odds ratios (OR) and 95% confidence interval (CI) by the Mantel-Haenszel method. We applied GRADE criteria to judge overall quality of the evidence.

MAIN RESULTS

The search identified six new RCTs, resulting in 22 included RCTs involving 3171 women at high risk of OHSS for this updated review. The dopamine agonists were cabergoline, quinagolide, and bromocriptine. Dopamine agonists versus placebo or no intervention Dopamine agonists probably lowered the risk of moderate or severe OHSS compared to placebo/no intervention (OR 0.32, 95% CI 0.23 to 0.44; 10 studies, 1202 participants; moderate-quality evidence). This suggests that if the risk of moderate or severe OHSS following placebo/no intervention is assumed to be 27%, the risk following dopamine agonists would be between 8% and 14%. We are uncertain of the effect of dopamine agonists on rates of live birth (OR 0.96, 95% CI 0.60 to 1.55; 3 studies, 362 participants; low-quality evidence). We are also uncertain of the effect of dopamine agonists on clinical pregnancy, multiple pregnancy, miscarriage  or adverse events (very low to low-quality evidence). Dopamine agonists plus co-intervention versus co-intervention Dopamine agonist plus co-intervention (hydroxyethyl starch, human albumin, or withholding ovarian stimulation 'coasting') may decrease the risk of moderate or severe OHSS compared to co-intervention (OR 0.48, 95% CI 0.28 to 0.84; 4 studies, 748 participants; low-quality evidence). Dopamine agonists may improve rates of live birth (OR 1.21, 95% CI 0.81 to 1.80; 2 studies, 400 participants; low-quality evidence). Dopamine agonists may improve rates of clinical pregnancy and miscarriage, but we are uncertain if they improve rates of multiple pregnancy  or adverse events (very low to low-quality evidence). Dopamine agonists versus other active interventions We are uncertain if cabergoline improves the risk of moderate or severe OHSS compared to human albumin (OR 0.21, 95% CI 0.12 to 0.38; 3 studies, 296 participants; very low-quality evidence), prednisolone (OR 0.27, 95% CI 0.05 to 1.33; 1 study; 150 participants; very low-quality evidence), hydroxyethyl starch (OR 2.69, 95% CI 0.48 to 15.10; 1 study, 61 participants; very low-quality evidence), coasting (OR 0.42, 95% CI 0.18 to 0.95; 3 studies, 320 participants; very low-quality evidence), calcium infusion (OR 1.83, 95% CI 0.88 to 3.81; I² = 81%; 2 studies, 400 participants; very low-quality evidence), or diosmin (OR 2.85, 95% CI 1.35 to 6.00; 1 study, 200 participants; very low-quality evidence). We are uncertain of the effect of dopamine agonists on rates of live birth (OR 1.08, 95% CI 0.73 to 1.59; 2 studies, 430 participants; low-quality evidence). We are uncertain of the effect of dopamine agonists on clinical pregnancy, multiple pregnancy or miscarriage (low to moderate-quality evidence). There were no adverse events reported.

AUTHORS' CONCLUSIONS

Dopamine agonists probably reduce the incidence of moderate or severe OHSS compared to placebo/no intervention, while we are uncertain of the effect on adverse events and pregnancy outcomes (live birth, clinical pregnancy, miscarriage). Dopamine agonists plus co-intervention may decrease moderate or severe OHSS rates compared to co-intervention only, but we are uncertain whether dopamine agonists affect pregnancy outcomes. When compared to other active interventions, we are uncertain of the effects of dopamine agonists on moderate or severe OHSS and pregnancy outcomes.

THE ROLE OF HIGH FOLLICULAR LEVELS OF ANGIOTENSIN II AND VASCULAR ENDOTHELIAL GROWTH FACTOR IN ANTICIPATING THE DEVELOPMENT OF SEVERE OVARIAN HYPERSTIMULATION SYNDROME IN PATIENTS WITH PROPHYLACTIC CABERGOLINE THERAPY UNDERGOING AN IN VITRO FERTILIZATION PROCEDURE

Background and aims

Severe Ovarian Hyperstimulation Syndrome (OHSS) forms with very aggressive clinical evolution are still common, despite prophylactic measures. Besides the Vascular Endothelial Growth Factor (VEGF), there are other angiogenic factors, like Renin-Angiotensin-Aldosterone System (RAS), that might be associated with this disorder. Our study aims to evaluate the role of VEGF and Angiotensin II (ANG II) in the development of early severe OHSS, in high risk patients under prophylactic Cabergoline therapy.

Material and Methods

We recruited 192 patients undergoing in vitro fertilization (IVF) procedures with high risk for OHSS development. Out of these, 106 patients with OHSS were enrolled in the study, of which 28 subjects had a severe form of disease (group I), and 78 patients had a mild/moderate form (group II). We collected blood and follicular fluid from our study participants and determined serum and follicular VEGF and ANG II levels using Enzyme-Linked Immunosorbent Assay (ELISA) technique.

Results

Follicular VEGF, ANG II, and serum VEGF levels were significantly higher in group I versus group II. Serum VEGF titers were 645.97 versus 548.62 (p = 0.0008), follicular VEGF titers were 2919.52 versus 1093.68 (p < 0.0001), and follicular ANG II levels were 281.64 versus 65.76 (p < 0.0001). No significant differences have been shown between the two groups for serum ANG II levels.

Conclusion

Our study results provide evidence of a OHSS phenotype that is more prone to undergo severe clinical forms of disease, despite treatments with VEGF receptor blockers, and show that ANG II appears to play a major role alongside VEGF, in the development of these severe forms of disease.

A meta-analysis of pregnancy-related outcomes and complications in women with polycystic ovary syndrome undergoing IVF

This meta-analysis aimed to study whether pregnancy-related outcomes and complications differed between patients with polycystic ovary syndrome (PCOS) and those with other causes of infertility who had undergone IVF. A systematic search of PubMed, Embase, the Cochrane Library and Chinese databases was carried out to identify relevant studies published before July 2018. Outcomes were expressed as odds ratios (OR) and 95% confidence intervals (CI). Subgroup analyses and sensitivity analyses were also conducted. Twenty-nine studies were identified for inclusion. Women with PCOS had higher risks of miscarriage (OR 1.41, 95% CI 1.04-1.91), ovarian hyperstimulation syndrome (OR 4.96, 95% CI 3.73-6.60), gestational diabetes mellitus (OR 2.67, 95% CI 1.43-4.98), pregnancy-induced hypertension (OR 2.06, 95% CI 1.45-2.91), preterm birth (OR 1.60, 95% CI 1.25-2.04) and large-for-gestational-age babies (OR 2.10, 95% CI 1.01-4.37). Women with PCOS showed similar rates of clinical pregnancy, multiple pregnancy, ectopic pregnancy, small for gestational age and congenital malformations, and a higher live birth rate, compared with women without PCOS. This study provides an update on and comprehensive evidence to support the observation that despite the fact that PCOS patients achieve a better live birth rate, physicians should continue to consider them to be at high risk of adverse pregnancy-related outcomes.

Clinical outcomes of frozen embryo transfer cycles after freeze-all policy to prevent ovarian hyperstimulation syndrome

Objective

To compare the clinical pregnancy rate (CPR) and ongoing pregnancy rate (OPR) in frozen embryo transfers (FETs) following either freeze-all policy to prevent ovarian hyperstimulation syndrome (OHSS; freeze-all group) or excess embryo cryopreservation after fresh embryo transfer (surplus group).

Methods

The freeze-all group comprised 44 FET cycles performed in 25 women between 2010 and 2016. The surplus group comprised 53 FET cycles performed in 47 women during the same period. The cumulative CPR and OPR according to duration of cryopreservation (interval between cryopreservation and FET) was estimated using Kaplan-Meier plots. Cox regression analysis was used for identifying factor to affect to cryopreservation duration in cycles with pregnancy.

Results

In day 2–4 transfer cycles, the crude CPR (40% vs. 18.2%) and OPR (20% vs. 4.5%) were similar between the 2 groups. In day 5 transfer, the crude CPR (33.3% vs. 38.7%) and OPR (33.3% vs. 29%) were also similar between the 2 groups. The cumulative CPR (100% vs. 47.5%) and OPR (100% vs. 33.3%) in day 2–4 transfer as well as the cumulative CPR (46.7% vs. 100%) and OPR (46.7% and 74.8%) in day 5 transfer were also similar between the 2 groups. The median duration of cryopreservation was significantly shorter in the freeze-all group than in the surplus group (19.8 vs. 36.9 weeks, P=0.04). Previous history of delivery was the only factor associated with a shorter cryopreservation duration in cycles with pregnancy (hazard ratio, 0.18; 95% confidence interval, 0.05–0.65; P=0.01).

Conclusion

Freezing embryos to prevent OHSS and transferring the frozen embryos later may guarantee an acceptable reproductive outcome.

Randomized trial of combined cabergoline and coasting in preventing ovarian hyperstimulation syndrome during in vitro fertilization/intracytoplasmic sperm injection cycles

OBJECTIVE

To assess the efficacy of coasting alone, cabergoline alone, or combining both interventions for preventing ovarian hyperstimulation syndrome (OHSS) among high-risk patients undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment cycles.

METHODS

The present randomized controlled trial was conducted at the IVF unit of a university hospital in Cairo between October 28, 2013, and July 31, 2015. Patients undergoing IVF/ICSI considered at risk of OHSS were randomly allocated to coasting, cabergoline, or combined coasting and cabergoline. The primary outcome was the rate and degree of symptomatically assessed OHSS. Data were analyzed on a per-protocol basis.

RESULTS

There were 100 patients recruited to each group. The occurrence of early OHSS was lowest in the combination group compared with the other groups (P=0.002).

CONCLUSION

Combining coasting and cabergoline was associated with a lower OHSS rate compared with either therapy alone. CLINICALTRIALS.GOV: NCT01984320.

Dopamine agonists for preventing ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a potentially serious complication of ovarian stimulation in assisted reproduction technology (ART). It is characterised by enlarged ovaries and an acute fluid shift from the intravascular space to the third space, resulting in bloating, increased risk of venous thromboembolism and decreased organ perfusion. Most cases are mild, but forms of moderate or severe OHSS appear in 3% to 8% of in vitro fertilisation (IVF) cycles. The dopamine agonist cabergoline was introduced as a secondary prevention intervention for OHSS in women at high risk of OHSS undergoing ART treatment. As cabergoline seemed to be effective in preventing OHSS, other types of dopamine agonists, such as quinagolide and bromocriptine, have since been studied in ART to prevent OHSS.

OBJECTIVES

To assess the effectiveness and safety of dopamine agonists in preventing OHSS in high-risk women undergoing ART treatment.

SEARCH METHODS

We searched several databases from inception to August 2016 (Cochrane Gynaecology and Fertility Specialised Register of trials, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, PsycINFO, Clinicaltrials.gov and the World Health Organization International Trials Registry Platform (ICTRP)) for randomised controlled trials (RCTs) assessing the effect of dopamine agonist in preventing OHSS. We handsearched the reference lists of relevant studies.

SELECTION CRITERIA

We considered RCTs which compared dopamine agonists with placebo/no intervention or another intervention for preventing OHSS in high-risk women for inclusion. Primary outcome measures were incidence of moderate or severe OHSS and live birth rate. Secondary endpoints were clinical pregnancy rate, multiple pregnancy rate, miscarriage rate and any other adverse effects of the treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently screened titles, abstracts and full texts of publications, selected studies, extracted data and assessed risk of bias. We resolved any disagreements by consensus. We reported pooled results as odds ratios (OR) and 95% confidence interval (95% CI) by the Mantel-Haenszel method. In addition, we graded the overall quality of the evidence using GRADE criteria.

MAIN RESULTS

The search identified 14 new RCTs since the last published version of this review, resulting in 16 included RCTs involving 2091 high-risk women for this updated review. They evaluated three types of dopamine agonists: cabergoline, quinagolide and bromocriptine.When compared with placebo or no intervention, dopamine agonists seemed effective in the prevention of moderate or severe OHSS (OR 0.27, 95% CI 0.19 to 0.39; 1022 participants; 8 studies; I² = 0%; moderate quality evidence). This suggests that if 29% of women undergoing ART experience moderate or severe OHSS, the use of dopamine agonists will lower this to 7% to 14% of women. There was no evidence of a difference in live birth rate, clinical pregnancy rate, multiple pregnancy rate or miscarriage rate (very low to moderate quality evidence). However, taking dopamine agonists (especially quinagolide) may increase the incidence of adverse events such as gastrointestinal adverse effects (OR 4.54, 95% CI 1.49 to 13.84; 264 participants; 2 studies; I² = 49%, very low quality evidence).When we compared dopamine agonist plus co-intervention with co-intervention, there was no evidence of a difference in the outcomes of moderate or severe OHSS, live birth rate, clinical pregnancy rate, miscarriage rate or adverse events. The co-interventions were hydroxyethyl starch (two RCTs) and albumin (one RCT).Cabergoline was associated with a lower risk of moderate or severe OHSS compared with human albumin (OR 0.21, 95% CI 0.12 to 0.38; 296 participants; 3 studies; I² = 72%). However, there was no evidence of a difference between cabergoline and hydroxyethyl starch, coasting (withholding any more ovarian stimulation for a few days) or prednisolone. There was an increased clinical pregnancy rate in the cabergoline group when cabergoline was compared with coasting (OR 2.65, 95% CI 1.13 to 6.21; 120 participants; 2 studies; I² = 0%). In other respects, there was no evidence of a difference in clinical pregnancy rate, multiple pregnancy rate or miscarriage rate between cabergoline and other active interventions.The quality of the evidence between dopamine agonist and placebo or no intervention ranged from very low to moderate, mainly due to poor reporting of study methods (mostly a lack of details on randomisation or blinding) and serious imprecision for some comparisons.

AUTHORS' CONCLUSIONS

Dopamine agonists appear to reduce the incidence of moderate or severe OHSS in women at high risk of OHSS (moderate quality evidence). If a fresh embryo transfer is performed, the use of dopamine agonists does not affect the pregnancy outcome (live birth rate, clinical pregnancy rate and miscarriage rate) (very low to moderate quality evidence). However, dopamine agonists might increase the risk of adverse events, such as gastrointestinal symptoms. Further research should focus on dose-finding, comparisons with other effective treatments and consideration of combination treatments. Therefore, large, well-designed and well-executed RCTs that involve more clinical endpoints (e.g., live birth rate) are necessary to further evaluate the role of dopamine agonists in OHSS prevention.

Early onset ovarian hyperstimulation syndrome despite use of segmentation approach and ovarian hyperstimulation syndrome prophylaxis

We report a case of early onset severe ovarian hyperstimulation syndrome (OHSS) presenting with oliguria in an antagonist cycle triggered with GnRH agonist and a freeze-all approach. Prophylactic measures in the form of GnRH antagonist, cabergolin and plasma expanders were given after oocyte retrieval. Twenty-four hours after oocyte retrieval patient developed oliguria and moderate ascites. She was managed in ICU with albumin and diuretics. She responded to conservative management and did not require paracentesis. Severe OHSS can occur in PCOS patients even after using a segmented approach i.e. GnRH agonist trigger with a 'freeze all' policy. Patients at risk of OHSS should be closely monitored following ovum pickup even when an agonist trigger has been given, for early detection and management.

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.

Dopamine agonist inhibits vascular endothelial growth factor protein production and secretion in granulosa cells

BACKGROUND

Dopamine receptor 2 agonists (D2-ags) inhibit vascular endothelial growth factor (VEGF) secretion in luteinized granulosa cells (LGCs) both in vitro and in vivo. However, the mechanism of D2 regulation of the VEGF/VEGF Receptor 2 (VEGFR-2) pathway remains to be elucidated. We sought to determine the effects of D2 signaling on VEGF transcription and translation in LGCs, with the expectation of identifying potential D2-ag-based therapies for ovarian hyperstimulation syndrome (OHSS).

FINDINGS

LGCs from egg donors were cultured with chorionic gonadotropin (hCG) in the presence of Actinomycin-D (ActD) or Brefeldin-A (BFA) to evaluate the effects of a D2-ag, cabergoline (Cb2), on VEGF secretion. The contribution of the conventional Gi/Go, Gz and AKT/β-Arrestin pathways in the VEGF regulation was assessed by adding pertussis toxin (PTX), phorbol 12-myristate 13-acetate (PMA), or wortmannin (WT). While Cb2 inhibited VEGF secretion by interfering with VEGF peptide translation and secretion, inhibition of conventional D2 transduction pathways did not reverse Cb2-mediated inhibition of VEGF secretion.

CONCLUSIONS

The effects of D2-ag on VEGF translation and secretion are mediated by D2 signaling pathways that have yet to be described. We found that D2-ag inhibits VEGF secretion at the post-transcriptional level, suggesting that D2-ag treatment should be combined with therapies that inhibit VEGF transcription, such as the employment of LH or GnRH for triggering ovulation, to improve the efficacy of OHSS prevention.

Comparison of montelukast and cabergoline for prevention of ovarian hyperstimulation syndrome: in an experimental rat model

Ovarian hyperstimulation syndrome (OHSS) is a serious iatrogenic complication that can occur during assisted reproductive techniques. The aim of this study is to investigate the effects of the leukotriene receptor antagonist (montelukast) treatment in prevention of OHSS and compare to cabergoline treatment. Twenty-four immature female Wistar rats were assigned to four groups. Group 1 was the control group. In the remaining three groups, OHSS was induced through ovarian stimulation with gonadotropins. No treatment was given to Group 2. Group 3 was administered a low-dose 100 mg/kg cabergoline treatment and Group 4 was received 20 mg/kg montelukast. Body weight, ovarian weight, vasculary permability (VP), peritoneal fluid vascular endothelial growth factor (VEGF) values and VEGF immune-expression were compared between the groups. Both cabergoline and montelukast prevented progression of OHSS compared to the OHSS group. Body weight, ovarian weight, VP, peritoneal fluid VEGF values and VEGF expression were significantly lower in both cabergoline- and montelukast-treated rats than in those not treated OHSS group. In conclusion, montelukast is an effective option for prevention of OHSS, as well as cabergoline. Montelukast may be a new treatment option to prevent and control the OHSS.

On-label and off-label drug use in the treatment of female infertility

Female infertility affects millions of couples worldwide and is estimated to account for one-third of all cases of infertility. The purpose of this article is to review the uses of both off-label treatments and those approved by the US Food and Drug Administration for female infertility, by examining the mechanism of action, the side-effect profile, fetal anomaly risks, and contraindications for the various drugs.

Freeze-all policy: is it time for that?

PURPOSE

This publication will evaluate the available evidence in the literature comparing fresh embryo transfer (ET) and elective frozen-thawed embryo transfer (FET) regarding the possible interference of controlled ovarian stimulation (COS) in implantation and endometrial receptivity, IVF safety, and obstetric and perinatal outcomes.

METHODS

We performed a review in the literature of the available evidence comparing fresh to elective FET (freeze-all policy).

RESULTS

The improvements made in cryopreservation techniques have led to few or no detrimental effects to the embryo and have resulted in no consequences to the offspring when compared to fresh embryos; this has allowed reproductive practitioners to create the freeze-all policy (when all viable embryos are electively cryopreserved in the fresh cycle and transferred in a posterior cycle). There are increasing concerns about the adverse effects associated with COS over the endometrial and uterine environments, as well as with the safety of COS in pregnancies that have originated from fresh ET during in vitro fertilization (IVF) treatments. COS may contribute to modifications in the endometrium, which might be related to poorer outcomes when fresh ET is performed. It has been suggested that obstetric and perinatal outcomes in pregnancies resulting from fresh ET are poorer when compared with those that occur after FET. In cycles with fresh ET, there is still a risk of ovarian hyperstimulation syndrome (OHSS).

CONCLUSION

There is growing evidence in the literature suggesting better IVF outcomes, and decreased obstetric and perinatal morbidity when adopting the freeze-all policy instead of fresh ET.

Cabergoline administration prevents development of moderate to severe ovarian hyperstimulation syndrome and it contributes to reduction in ovarian volume

Purpose

The aim of this study was to determine the prophylactic effects of cabergoline on ovarian hyperstimulation syndrome (OHSS) after oocyte retrieval.

Methods

A total of 187 women underwent controlled ovarian stimulation using gonadotropin releasing hormone (GnRH) agonist long protocol or flexible GnRH antagonist protocol for in vitro fertilization. They responded excessively to ovulation induction, and fresh embryo transfers were canceled. Sixty-one patients in the intervention group were administered oral cabergoline (0.5 mg) three times after oocyte retrieval (day 0, 2, and 4 following the oocyte retrieval). Ultrasonography and blood examination were performed on the seventh day following oocyte retrieval. The main outcomes measured were the incidence of OHSS, estimated ovarian volumes, ascites, hematocrits, and white blood cell counts.

Results

The incidence of moderate to severe OHSS was lower after cabergoline administration (9.8 vs. 23.0 %, p = 0.03). The ovarian volumes reduced after intervention (96.2 vs. 145.5 cm³, p = 0.008). The reduction was evident in the patients with agonist long protocol (92.1 vs. 167.5 cm³, p = 0.0005). No significant differences were observed for other factors.

Conclusions

Cabergoline has a favorable effect on the prevention of moderate to severe OHSS affiliated with ovarian volume reduction.

Dopamine and serotonin regulate tumor behavior by affecting angiogenesis

The biogenic amines dopamine and serotonin are neurotransmitters and hormones, which are mainly produced in the central nervous system and in the gastro-intestinal tract. They execute local and systemic functions such as intestinal motility and tissue repair. Dopamine and serotonin are primarily stored in and transported by platelets. This review focuses on the recently recognized role of dopamine and serotonin in the regulation of tumor behavior by affecting angiogenesis and tumor cell proliferation. Preclinical studies demonstrate that dopamine inhibits tumor growth via activation of dopamine receptor D2 on endothelial and tumor cells. Serotonin stimulates tumor growth via activation of serotonin receptor 2B on endothelial cells and serotonin receptors on tumor cells. Drugs that stimulate dopamine receptor D2 or inhibit serotonin receptors are available and therefore clinical intervention studies for cancer patients are within reach.

Dopamine receptor 2 activation inhibits ovarian vascular endothelial growth factor secretion in an ovarian hyperstimulation syndrome (OHSS) animal model: implications for treatment of OHSS with dopamine receptor 2 agonists

OBJECTIVE

To explore whether a dopamine receptor 2 agonist (D2-ag) can prevent ovarian hyperstimulation syndrome (OHSS) in a rat model by decreasing ovarian vascular endothelial growth factor (VEGF) production.

DESIGN

Experimental study in an OHSS animal model.

SETTING

University-affiliated infertility center.

PATIENT(S)

Immature Wistar rats.

INTERVENTION(S)

Immature rats were stimulated with gonadotropins to mimic OHSS and treated with a D2-ag and/or D2-antagonists (D2-ant). Vascular permeability (VP) was measured at the endpoint, and ovaries were collected to assess the effects of these drugs on VEGF production.

MAIN OUTCOME MEASURE(S)

VP was estimated by measuring the peritoneal extravasation of a previously injected dye. Ovarian VEGF mRNA expression and VEGF protein levels were assessed by quantitative real-time PCR and Western blots, respectively.

RESULT(S)

The D2-ag exerted a reduction in VP that was associated with a drastic decrease in VEGF protein production in OHSS rat ovaries. The effects of this D2-ag on VP and VEGF protein levels were partially reversed by concomitant administration of a D2-ant. Ovarian VEGF mRNA expression levels were unaffected by these drugs in OHSS rats.

CONCLUSION(S)

D2-ags prevent increased VP in OHSS rats by decreasing ovarian VEGF production, very likely through a D2-mediated post-transcriptional mechanism. Given the dose-dependent inhibitory effect of D2-ags on ovarian VEGF production reported herein, we infer that current OHSS therapies used in humans may be improved by increasing the intraovarian concentration of D2-ags in these patients.

Kinase insert domain receptor/vascular endothelial growth factor receptor 2 (KDR) genetic variation is associated with ovarian hyperstimulation syndrome

BACKGROUND

The objective of this investigation was to determine if kinase insert domain/vascular endothelial growth factor receptor 2 (KDR/VEGFR2) genetic variation was associated with the development of ovarian hyperstimulation syndrome (OHSS) in patients undergoing controlled ovarian hyperstimulation (COH).

METHODS

This was a case-control study of 174 patients who underwent controlled ovarian stimulation. Patient blood samples were genotyped for single nucleotide polymorphisms (SNPs) spanning the KDR locus. OHSS development, clinical outcome variables, SNP and haplotype frequencies were compared between control (n = 155) and OHSS (n = 19) groups.

RESULTS

Patients who developed OHSS had significantly higher response markers (estradiol levels of the day of hCG administration, number of follicles developed, number of eggs retrieved) than control patients. When adjusted for age and self-identified race, the rs2305945 G/T genotype was associated (P = 0.027) with a decreased risk (OR = 0.30; 95% CI = 0.10, 0.93) of developing OHSS using an overdominant model. The rs2305945 G/T variant was also associated with decreased COH response (number of follicles, number of eggs retrieved) in an overdominant model. The rs2305948, rs1870378, rs2305945 (C-T-G) haplotype was associated with both decreased COH response and OHSS risk (unadjusted OR = 0.10; 95% CI = 0.01, 0.80, P = 0.031).

CONCLUSIONS

The KDR receptor is believed to play a central role OHSS development and is a target for pharmacological prevention of OHSS. These results indicate that genetic variation in the KDR gene may impact individual risk of developing OHSS from COH. In addition, the rs2305948 SNP and C-T-G haplotype might serve as potential biomarkers for poor ovarian response to COH.

Calcium gluconate infusion is as effective as the vascular endothelial growth factor antagonist cabergoline for the prevention of ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic and potentially life-threatening disease process, which may occur in healthy young women undergoing controlled ovarian hyperstimulation for assisted reproduction. As the treatment is largely empirical, prevention forms the mainstay of management.

OBJECTIVE

The present study was aimed to evaluate the effectiveness of intravenous (IV) calcium gluconate infusion in comparison to the dopamine agonist cabergoline (Cb2) in preventing OHSS in high risk patients undergoing assisted reproductive technique cycles.

MATERIALS AND METHODS

It was a comparative study wherein the 202 high risk patients undergoing in vitro-fertilization over a period of 18 months after meeting the strict inclusion and the exclusion criteria, were randomly divided into two groups (98 subjects in Group I and 104 in Group II). Women in Group I were administered IV calcium gluconate while the remaining 104 received the dopamine agonist Cb2. The 104 patients belonging to Group II were started Cb2 0.5 mg/day from the day of ovulation trigger and continued until the next 8 days while the 98 high risk patients from Group I were infused with 10 ml of 10% calcium gluconate solution in 200 ml physiologic saline within 30 min of ovum pick up and continued thereafter on day 1, day 2 and day 3.

RESULTS

The occurrence of OHSS was seen in only nine patients (in the calcium infusion group, when compared with 16 patients (9.2% vs. 15.4%) who were administered Cb2, but it was not statistically significant. However, only one had severe OHSS in Group I, whereas two women were diagnosed as severe OHSS belonging to the Cb2 arm.

CONCLUSION

Our results document that calcium infusion can effectively prevent severe OHSS and decreases OHSS occurrence rates when used for high-risk patients, but does not suggest its superiority over Cb2. With comparable success rates, either of them can be employed as a preventive strategy for OHSS.

Dopamine receptor 2 activation inhibits ovarian vascular endothelial growth factor secretion in vitro: implications for treatment of ovarian hyperstimulation syndrome with dopamine receptor 2 agonists

OBJECTIVE

To ascertain whether vascular endothelial growth factor (VEGF) secretion by luteinized granulosa cells (GCs) is modulated by the dopaminergic system in a dose-dependent fashion and how this is related to the differential efficacy of dopamine receptor 2 (D2)-agonists (D2-ag) in preventing ovarian hyperstimulation syndrome (OHSS).

DESIGN

The relationship between the dopaminergic system and VEGF secretion in luteinized GCs was evaluated. Archived human ovaries were immunostained to characterize D2 expression.

SETTING

University affiliated infertility center.

PATIENT(S)

Premenopausal women and egg donors.

INTERVENTION(S)

Luteinized GCs were cultured with the D2-ag cabergoline. Human ovarian sections were immunostained for D2.

MAIN OUTCOME MEASURE(S)

The VEGF was measured by ELISA and D2 expression was evaluated by In-Cell ELISA. The D2 expression throughout the luteal phase was characterized by immunohistochemistry.

RESULT(S)

The VEGF secretion was decreased by the D2-ag in a dose-dependent fashion. The efficiency of this process was correlated with the amount of D2 expressed by luteinized GCs. A decrease in D2 expression in ovarian sections was observed during the late luteal phase.

CONCLUSION(S)

The efficacy of D2-ags in preventing OHSS might rely on their capacity to inhibit VEGF secretion by luteinized GCs. Because this capacity is dose-dependent, increasing the intraovarian concentration of D2-ags should be explored as a means of increasing the efficacy of these drugs in preventing OHSS.

Dopamine agonists in prevention of ovarian hyperstimulation syndrome

The aim of this review is to analyze the efficacy of different dopamine agonists in the prevention of ovarian hyperstimulation syndrome (OHSS). Cabergoline, quinagolide and bromocriptine are the most common dopamine agonists used. There are wide clinical variations among the trials in the starting time (from the day of human chorionic gonadotrophin (hCG) to the day following oocyte retrieval); the duration of the treatment (4-21 days), the dose of cabergoline (0.5 mg or 0.25 mg orally) and in the regimens used. At present, the best known effective regimen is 0.5 mg of cabergoline for 8 days or rectal bromocriptine at a daily dose of 2.5 mg for 16 days. Dopamine agonists have shown significant evidences of their efficacy in the prevention of moderate and early-onset OHSS (9.41%), compared with a placebo (21.45%), which cannot be confirmed for the treatment of late OHSS. It would be advisable to start with the treatment on the day of hCG injection or preferably a few hours earlier. The use of dopamine agonists should be indicated in patients at high risk of OHSS, as well as in patients with a history of previous OHSS even without evident signs of the syndrome.

Mild/minimal stimulation protocol for ovarian stimulation of patients at high risk of developing ovarian hyperstimulation syndrome

BACKGROUND

Recently, an increased scientific interest was focused on mild approaches for ovarian stimulation in clinical practice. Milder stimulation aims to develop safer and more patient-friendly protocols which are more physiological, less drug use, less expensive and the risks of treatment are highly minimized.

AIM

To investigate the efficacy and safety of a mild ovarian stimulation protocol in patients at high risk of developing ovarian hyperstimulation syndrome (OHSS), compared to conventional long down-regulation protocol.

SUBJECTS AND METHODS

This a prospective, open, randomized study, included 349 infertile patients considered at high risk of developing OHSS, undergoing in vitro fertilization treatment in two private assisted reproduction centers. The patients were randomized into two groups: group A (n = 148) had a mild/minimal stimulation protocol of recombinant FSH (rFSH) combined with GnRH antagonist. Group B (n = 201) (control group) had a standard long protocol of rFSH combined with GnRH agonist.

RESULTS

There was no significant difference observed between the two groups regarding the mean number of oocytes retrieved per patient, mature metaphase II oocytes, fertilization rate, and embryo cleavage rate. Significantly higher implantation rate (21.5 vs 14.5 %) (p < 0.05), pregnancy rate (37.7 vs 23.4 %) (p < 0.05), and delivery rate (32.8 vs 20.1 %) (p < 0.05) were observed in favor of groups A compared to group B. Lower proportion of patients (4.7 %), though not statistically significant, has developed OHSS in group A compared to group B (8.4 %).

CONCLUSION

Our study shows that mild stimulation regimen is highly effective for ovarian stimulation of patients who have experienced OHSS complication without increasing the risk of OHSS.

Targeting angiogenesis in the pathological ovary

The ovary is a key tissue in the study of physiological neo-vascularisation in the adult and its study has highlighted important molecules involved in the regulation of angiogenesis in vivo. These include vascular endothelial growth factor, delta-like ligand 4, thrombospondin-1, prokineticin-1 and prostaglandin E2. Targeting these molecular pathways has therapeutic potential and their manipulation has an increasing preclinical and clinical role in the management of the pathological ovary. Targeting angiogenic pathways has utility in the promotion of ovarian angiogenesis to improve tissue and follicle survival and function as well as the prevention and management of ovarian hyperstimulation syndrome. There is a theoretical possibility that targeting angiogenesis may improve the function of the polycystic ovary and a real role for targeting angiogenesis in ovarian cancer.

Preventing ovarian hyperstimulation syndrome: cabergoline versus coasting

PURPOSE

The use of cabergoline and coasting are both effective in reducing the risk of ovarian hyperstimulation syndrome (OHSS). Our aim was to compare the effectiveness of cabergoline with coasting to prevent moderate-severe OHSS.

METHODS

Fifty-seven consecutive infertile patients (81 cycles) at risk of developing OHSS were enrolled through our computerized IVF database system. Inclusion criteria were: (i) E2 level on the day of human chorionic gonadotrophin (hCG) greater than 3,500 pg/ml; (ii) patients who underwent luteal long GnRH agonist cycle; (iii) patients who used cabergoline for OHSS prevention; (iv) patients who underwent coasting for OHSS prevention. The cabergoline group constituted 17 patients (26 cycles) who started using 0.5 mg oral cabergoline daily for 8 days on the day of hCG, whereas the coasting group constituted 40 patients (55 cycles) who underwent coasting.

RESULTS

Both groups were comparable regarding the women's mean age, body mass index and duration of infertility. Implantation rate, clinical pregnancy per embryo transfer and miscarriage rates were not different between the two groups. There was no OHSS in the cabergoline group (0 %), whereas there were two OHSS (3.6 %) in the coasting group; however, this difference was not significant.

CONCLUSIONS

In conclusion, 0.5 mg daily use of cabergoline for 8 days beginning from hCG administration is a very effective way to reduce moderate-severe OHSS without sacrificing pregnancy rates in patients at risk of developing OHSS.

Cabergoline as treatment of ovarian hyperstimulation syndrome: a review

One of the most serious complications of assisted reproduction techniques is ovarian hyperstimulation syndrome (OHSS). OHSS not only increases morbidity and mortality in IFV cycles, but also causes significant other problems, as cancelled in vitro fertilization (IVF) cycles, prolonged hospitalization, causing emotional and sociofinancial consequences. Several treatments for OHSS have been proposed and among these Cabergoline (Cb2). Despite the above-mentioned beneficial effect, Cb2 has not been widely used in everyday's clinical practice. With our study, we try to review all studies with strong evidence examining Cb2 use for OHSS prevention.

GnRH analogues in the prevention of ovarian hyperstimulation syndrome

The GnRH analogue (agonist and antagonist GnRH) changed ovarian stimulation. On the one hand, it improved chances of pregnancy to obtain more oocytes and better embryos. This leads to an ovarian hyper-response, which can be complicated by the ovarian hyperstimulation syndrome (OHSS). On the other hand, the GnRH analogue can prevent the incidence of OHSS: GnRH antagonist protocols, GnRH agonist for triggering final oocyte maturation, either together or separately, coasting, and the GnRH analogue may prove useful for avoiding OHSS in high-risk patients. We review these topics in this article.

Short-term pharmacological suppression of the hyperprolactinemia of infertile hCG-overproducing female mice persistently restores their fertility

Female infertility is often associated with deregulation of hormonal networks, and hyperprolactinemia is one of the most common endocrine disorders of the hypothalamic-pituitary axis affecting the reproductive functions. We have shown previously that transgenic female mice overexpressing human chorionic gonadotropin β-subunit (hCGβ+ mice), and producing elevated levels of bioactive LH/hCG, exhibit increased production of testosterone and progesterone, are overweight and infertile, and develop hyperprolactinemia associated with pituitary lactotrope adenomas in adult age. In the present study, we analyzed the influence of the hyperprolactinemia of hCGβ+ females on their reproductive phenotype by treating them with the dopamine agonists, bromocriptine and cabergoline. Long-term bromocriptine treatment of adult mice was effective in the control of obesity, pituitary growth, and disturbances in the hormone profile, demonstrating that hyperprolactinemia was the main cause of the hCGβ+ female phenotype. Interestingly, short-term treatment (1 wk) with cabergoline applied on 5-wk-old mice corrected hyperprolactinemia, hyperandrogenism, and hyperprogesteronemia, prevented pituitary overgrowth, normalized gonadal function, and recovered fertility of adult hCGβ+ females after hormone-induced and natural ovulation. The same cabergoline treatment in the short term applied on 3-month-old hCGβ+ females failed to recover their reproductive function. Hence, we demonstrated that the short-term cabergoline treatment applied at a critical early stage of the phenotype progression effectively prevented the hyperprolactinemia-associated reproductive dysfunction of hCG-overproducing females.

Can dopamine agonist at a low dose reduce ovarian hyperstimulation syndrome in women at risk undergoing ICSI treatment cycles? A randomized controlled study

OBJECTIVE

Dopamine agonists were proposed as a preventive strategy for severe ovarian. The aim of this randomized controlled study is to evaluate the role of dopamine agonist at lower doses (0.25mg) as a preventive strategy of severe hyperstimulation syndrome (OHSS) in women at high risk in IVF/ICSI treatment cycles.

STUDY DESIGN

Two hundred women at risk to develop OHSS undergoing IVF/ICSI treatment cycle were included; the study group received 0.25mg of cabergoline for 8 days from the day of HCG administration versus no treatment for the prevention of OHSS. Reduction of the incidence OHSS was the primary outcome.

RESULTS

The overall incidence of OHSS was significantly reduced, almost 50%, in cabergoline group in comparison with control group (RR: 0.5, 95% CI: 0.29-0.83), with absolute risk reduction following cabergoline administration 11% (ARR: 0.11, 95% CI: 1.09-20.91). The corresponding number needed to treat (NNT) was 9.

CONCLUSION

Prophylactic treatment with the dopamine agonist, cabergoline, at lower doses (0.25mg) reduces the incidence of OHSS in women at high risk undergoing IVF/ICSI treatment.

VEGF antagonist for the prevention of ovarian hyperstimulation syndrome: Current status

Ovarian Hyperstimulation Syndrome (OHSS) an iatrogenic and potentially life-threatening complication resulting from an exaggerated response to ovulation induction with gonadotropins during assisted reproductive technologies, is a self-limiting disorder with a broad spectrum of clinical manifestations related to increased capillary permeability and fluid retention brought about by many biochemical mediators especially vascular endothelium growth factor (VEGF), playing a pivotal role in its pathophysiology. Although various strategies had been proposed and tried to prevent this serious complication none was found to be completely effective. With the current knowledge and understanding of the causative molecule i.e. VEGF in the pathogenesis of OHSS, pharmacologic tools targeting this member of the family of heparin binding proteins, seems promising. Antagonizing and blocking VEGF action by dopamine agonists especially Cabergoline has shown to be a valid alternative to overcome the changes induced by the gonadotropins. Delaying embryo transfer with embryo cryopreservation definitely reduces the incidence of OHSS but not the early OHSS. In-vitro maturation of oocytes a major breakthrough in the field of ART although totally eliminates the risk of OHSS is highly labor intensive and cannot routinely carried in all cycles. Thus the newer drugs, mainly the dopamine agonists in the light of the new pathogenic and pharmacological evidence, should definitely be considered for prevention of both early and late OHSS.

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.

Cabergoline for preventing ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a complication resulting from administration of human chorionic gonadotrophin (hCG) in assisted reproduction technology (ART) treatment. Most case are mild, but forms of moderate or severe OHSS appear in 3% to 8% of in vitro fertilisation (IVF) cycles. Recently, the dopamine agonist cabergoline has been introduced as a secondary prevention intervention for OHSS in women at high risk of OHSS who are undergoing ART treatment.

OBJECTIVES

To assess the effectiveness and safety of cabergoline in preventing ovarian hyperstimulation syndrome (OHSS) in high-risk women undergoing ART treatment.

SEARCH METHODS

Major medical databases (Cochrane Menstrual Disorders and Subfertility Group Specialised Register of trials, CENTRAL (The Cochrane Library), MEDLINE, EMBASE and PsycINFO) were systematically searched for randomised controlled trials (RCTs) assessing the effect of cabergoline in preventing OHSS. Databases were searched up to September 2011. Registers of clinical trials, abstracts of scientific meetings and reference lists of included studies were searched. No language restrictions were applied.

SELECTION CRITERIA

RCTs which compared cabergoline with placebo, no treatment or another intervention for preventing OHSS in high-risk women were considered for inclusion. Primary outcome measures included incidence of moderate or severe OHSS and live birth rate. Secondary endpoints were clinical pregnancy rate, multiple pregnancy rate, miscarriage rate and any other adverse effects of the treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently screened titles, abstracts and the full text of publications; extracted data; and assessed risk of bias. Any disagreements were resolved by consensus. Pooled results were reported as odds ratio (OR) and 95% confidence interval (95% CI) by the Mantel-Haenszel method.

MAIN RESULTS

Only two trials involving 230 women met the inclusion criteria. Both studies had a moderate risk of bias. Oral cabergoline, 0.5 mg daily, was given as an intervention and compared with a matched placebo. A statistically significant reduction in OHSS was observed in the cabergoline treated group (OR 0.40, 95% CI 0.20 to 0.77; 2 RCTs, 230 women) with a number needed to treat (NTT) of 7. There was a statistically significant difference in the incidence of moderate OHSS, favouring cabergoline (OR 0.38, 95% CI 0.19 to 0.78; 2 RCTs, 230 women) but not in severe OHSS (OR 0.77, 95% CI 0.24 to 2.45; 2 RCTs, 230 women). There was no significant difference in the clinical pregnancy rate (OR 0.94, 95% CI 0.56 to 1.59; 2 RCTs, 230 women), miscarriage rate (OR 0.31, 95% CI 0.03 to 3.07; 1 RCT, 163 women) or any other adverse effects of the treatment (OR 2.07, 95% CI 0.56 to 7.70; 1 RCT, 67 women). However, no data on multiple pregnancy rate or live birth rate were reported in either trial.

AUTHORS' CONCLUSIONS

Cabergoline appears to reduce the risk of OHSS in high-risk women, especially for moderate OHSS. The use of cabergoline does not affect the pregnancy outcome (clinical pregnancy rate, miscarriage rate), nor is there an increased risk of adverse events. Further research should consider the risk of administering cabergoline and the comparison between cabergoline and established treatments (such as intravenous albumin and coasting). Large, well-designed and well-executed RCTs that involve more clinical endpoints are necessary to further evaluate the role of cabergoline in OHSS prevention.

Etiology of OHSS and use of dopamine agonists

Vascular endothelial growth factor is the factor that causes increased capillary permeability and therefore the most serious manifestations of ovarian hyperstimulation syndrome. Dopamine agonists can both prevent and treat ovarian hyperstimulation syndrome by blocking expression of the vascular endothelial growth factor receptor.

Comparison of cabergoline and intravenous albumin in the prevention of ovarian hyperstimulation syndrome: a randomized clinical trial

PURPOSE

To compare the efficacy of cabergoline (Cb2) and intravenous human albumin (HA) in the prevention of ovarian hyperstimulation syndrome.

METHODS

In this randomized controlled trial study, 138 women who were at high risk for developing OHSS were randomly allocated into two groups. In Group one, 20 gr of HA 20% was infused over 1 h. Group two received 0.5 mg per day of Cb2 orally for 7 days, starting on oocyte pickup day. All patients were visited seven and 14 days after oocyte retrieval to determine early clinical or ultrasound evidence of OHSS.

RESULTS

Moderate OHSS was observed in 33 versus 14 cases in the HA and Cb2 groups, respectively, which was significantly different. The number of severe OHSS cases in the HA group was significantly higher than in the Cb2 group (P < 0.001).

CONCLUSIONS

Prophylactic oral low dose cabergoline was more effective and less costly than intravenous human albumin in the prevention of OHSS in high-risk patients.

Update on management of ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) is a relatively common complication of ovarian stimulation and can be life threatening. The pathophysiology of OHSS is characterized by increased capillary permeability, leading to leakage of fluid from the vascular compartment, with third-space fluid accumulation and intravascular dehydration. The increased intra-abdominal pressure indicated that OHSS may be considered a compartment syndrome. Vascular endothelial growth factor, also known as vascular permeability factor, has emerged as one of the mediators intrinsic to the development of OHSS. Conventional management is focused on supportive care until the spontaneous resolution of the condition. The standard of care for treatment-monitoring of appropriate clinical parameters, fluid balance management, thrombosis prophylaxis, and ascites treatment-should prevent severe morbidity in most cases. This review will cover inpatient and outpatient management. The potential therapeutic approach targeting the vascular endothelial growth factor system will be discussed.

[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.