Recombinant versus urinary human chorionic gonadotrophin for final oocyte maturation triggering in IVF and ICSI cycles

Metabolic changes in follicular fluids of patients treated with recombinant versus urinary human chorionic gonadotropin for triggering ovulation in assisted reproductive technologies: a metabolomics pilot study

INTRODUCTION

The main goal of this retrospective cohort study is the assessment of the effects of administration of recombinant-hCG (r-hCG) versus urinary-hCG (u-hCG) on follicular fluid (FF) composition of women who underwent in vitro fertilization (IVF) treatments.

MATERIALS AND METHODS

We selected 70 patients with infertility attributable to tubal diseases, unexplained infertility, and male factor. Metabolomics analysis of their FFs was performed by ¹H nuclear magnetic resonance (¹H NMR) spectroscopy in combination with multivariate analysis to interpret the spectral data. Univariate statistical analysis was applied to investigate the possible correlations between clinical parameters and between clinical parameters and metabolites identified by NMR.

RESULTS

According to the type of hCG used, significant differences were detected in FFs of women with male factor and unexplained infertility, both in qualitative and quantitative terms, for some metabolites as cholesterol, citrate, creatine, β-hydroxybutyrate, glycerol, lipids, amino acids (Glu, Gln, His, Val, Lys) and glucose. No significant difference was observed in women with tubal diseases. Besides, the number of MII oocytes in the u-hCG-treated groups correlates positively with glutamate in tubal disease and with glycerol in unexplained infertility. In the r-hCG-treated groups, the number of MII oocytes correlates positively with lipid in tubal disease, positively with citrate and negatively with glucose in male infertility.

CONCLUSIONS

Metabolite composition of FF changes according to different type of hCG treatment and this can be related to oocyte development and subsequent outcome. According to the data of this study, different types of hCG should be used in relation to the diagnosis of infertility to obtain better results in inducing oocyte maturation in women undergoing IVF.

A Multicenter, Randomized, Equivalence Trial of a New Recombinant Human Chorionic Gonadotropin Preparation versus Ovitrelle® for Ovulation in Women Undergoing Intrauterine Insemination Following Ovarian Stimulation

Context:

A new indigenous recombinant human chorionic gonadotropin (r-hCG) has been developed in India with a comparable pharmacological profile to that of Ovitrelle^® (Merck Serono).

Aims:

This study aims to compare the efficacy and safety of the new r-hCG with that of Ovitrelle for induction of ovulation in women undergoing intrauterine insemination (IUI).

Settings and Design:

Randomized (2:1), multicenter, open-label, equivalence clinical trial conducted in India.

Subjects and Methods:

A total of 217 women, aged 20–37 years, undergoing IUI were administered the new r-hCG (test) 250 mcg or Ovitrelle 250 mcg (comparator) after ovarian stimulation with gonadotropins. The ovulation rate was compared as the primary outcome. In addition, pregnancy rates, incidence of adverse events (AEs), and development of immunogenicity were assessed. Statistical Analysis Used: The ovulation and pregnancy rates were compared using Chi-squared test with statistical significance at P < 0.05.

Results:

With 144 women in the test group and 73 in the comparator group, the ovulation rate (85.4% vs. 78.1%; P = 0.17) and pregnancy rate (serum β hCG test) (11.8% vs. 12.3%; P = 0.91) were similar in both groups. A total of 15 AEs were reported (11 in the test r-hCG group and 4 in the comparator group) in 11 women; none of these were serious, and all were judged to be unrelated to the study drug. No subject developed immunogenic reaction to the test drug.

Conclusions:

The new preparation of r-hCG was equivalent to the conventional preparation of r-HCG in the induction of ovulation in patients undergoing IUI.

Ovarian Hyperstimulation Syndrome: A Narrative Review of Its Pathophysiology, Risk Factors, Prevention, Classification, and Management

Ovarian hyperstimulation syndrome (OHSS) is a serious complication of ovulation induction that usually occurs after gonadotropin stimulation, followed by human chorionic gonadotropin administration, for infertility treatment. The existing knowledge about the pathophysiology, risk factors, and primary and secondary methods for the prevention of OHSS is reviewed in this manuscript. The clinical manifestations and characteristics of mild, moderate, severe, and critical forms of the syndrome are defined. The methods of handling affected cases as outpatient or in-hospital management methods as well as indications for hospitalization are summarized in this review. The clinical and biochemical routes of assessing and monitoring hospitalized patients with OHSS, various drugs and medical treatment strategies including indications for aspiration of the ascitic fluid and pleural effusion, and also rare indications for surgery are briefly explained in this article. Severe OHSS, which two decades ago was considered an iatrogenic life-threatening condition, can now be effectively prevented or managed during the early stages. An OHSS-free clinic can be established nowadays by carefully considering the endocrinology of ovulation and using appropriate and dose-adjusted pharmaceutical agents, which are summarized and discussed in this review.

Pharmacokinetic, pharmacodynamic, and clinical aspects of ovulation induction agents: A review of the literature

Controlled ovarian hyperstimulation is a key step for successful outcomes of assisted reproductive technique cycle outcomes. Many medications are available, which are commonly useed solely or in combination to achieve multiple follicular development. Pharmacokinetic, pharmacodynamic, and clinical information of ovulation induction drugs deserve to be elucidated for every individual patient before commencing infertility treatment. New concepts and new treatment protocols are introduced as ovulation physiology is understood by infertility specialists. Increasing treatment success by minimizing aderse effects is a milestone of all ovarian stimulation protocols that use these novel interventions. Achievement of a satisfactory cycle outcome includes retrieval of sufficient oocytes, a single clinical pregnancy, and avoidance of ovarian hyperstimulation syndrome. In this review, we evaluate the current literature to determine the most reliable and relevant information about the most used ovulation induction drugs.

Phase III trial comparing the efficacy and safety of recombinant- or urine-derived human chorionic gonadotropin for ovulation triggering in Japanese women diagnosed with anovulation or oligo-ovulation and undergoing ovulation induction with follitropin-alfa

Aim

Outside of Japan, recombinant-human chorionic gonadotropin (r-hCG) is widely used for the induction of final follicular maturation and early luteinization in women undergoing ovulation induction; whereas in Japan, urine-derived hCG (u-hCG) is predominantly used. The primary objective of this study was to demonstrate the non-inferiority of r-hCG to u-hCG for ovulation induction, as assessed by the ovulation rate.

Methods

This was an open-label, parallel-group, randomized, multicenter, phase III trial in Japanese women with anovulation or oligo-ovulation secondary to hypothalamic-pituitary dysfunction or polycystic ovary syndrome, undergoing ovulation induction with recombinant-human follicle-stimulating hormone. The women were randomized (2:1) to receive either a single 250 μg s.c. dose of r-hCG or a single 5000 IU i.m. dose of u-hCG for ovulation triggering.

Results

Eighty-one women were randomized to either r-hCG (n=54) or u-hCG (n=27). Ovulation occurred in 100% of the participants and treatment with r-hCG was observed to be non-inferior to u-hCG for ovulation induction. Overall, the type and severity of adverse events were as expected for women receiving fertility treatment.

Conclusion

This study demonstrated that r-hCG was non-inferior to u-hCG for inducing ovulation. Furthermore, r-hCG demonstrated an expected safety profile, with no new safety concerns identified.

An update on the prevention of ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome is a potentially life-threatening, but preventable iatrogenic complication of in vitro fertilisation treatment. In recent years, new strategies have been developed to minimise the risk of ovarian hyperstimulation syndrome after in vitro fertilisation, including better at-risk patient identification prior to starting treatment, the use of a lower human chorionic gonadotrophin dose or alternative medication instead of human chorionic gonadotrophin to induce final oocyte maturation such as gonadotrophin-releasing hormone agonist and kisspeptin in antagonist cycles, cryopreservation of all embryos and delayed embryo transfer, and the use of oral dopamine agonists after oocyte retrieval. In this article, the advantages and limitations of those new developments are discussed and future directions towards establishment of an ovarian hyperstimulation syndrome-free in vitro fertilisation clinic are explored.

Recombinant versus urinary human chorionic gonadotrophin for final oocyte maturation triggering in IVF and ICSI cycles

BACKGROUND

For the last few decades urinary human chorionic gonadotrophin (uhCG) has been used to trigger final oocyte maturation in cycles of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Recombinant technology has allowed the production of two drugs, recombinant human chorionic gonadotrophin (rhCG) and recombinant luteinising hormone (rLH), that can be used for the same purpose, to mimic the endogenous luteinising hormone (LH) surge. This allows commercial manufacturers to adjust production according to market requirements and to remove all urinary contaminants, facilitating the safe subcutaneous administration of a compound with less batch-to-batch variation. However, prior to a change in practice, it is necessary to compare the effectiveness of the recombinant drugs to the currently used urinary human chorionic gonadotrophin (uhCG).

OBJECTIVES

To assess the effects of subcutaneous rhCG and high dose rLH versus uhCG for inducing final oocyte maturation in subfertile women undergoing IVF and ICSI cycles.

SEARCH METHODS

We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (April 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 3), MEDLINE (1946 to April 2015), EMBASE (1980 to April 2015) and PsycINFO (1806 to April 2015) as well as trial registers at ClinicalTrials.gov on 13 May 2015 and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) search portal on 14 May 2015.

SELECTION CRITERIA

Two review authors independently scanned titles and abstracts and selected those that appeared relevant for collection of the full paper. We included randomised controlled trials comparing rhCG and rLH with urinary hCG for final oocyte maturation triggering in IVF and ICSI cycles for treatment of infertility in normogonadotropic women.

DATA COLLECTION AND ANALYSIS

Two authors independently performed assessment for inclusion or exclusion, quality assessment and data extraction. We discussed any discrepancies in the presence of a third author to reach a consensus. The primary review outcomes were ongoing pregnancy/live birth and incidence of ovarian hyperstimulation syndrome (OHSS). Clinical pregnancy, miscarriage rate, number of oocytes retrieved and adverse events were secondary outcomes. We combined data to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs) and assessed statistical heterogeneity using the I(2) statistic. We evaluated the overall quality of the evidence for the main comparisons using GRADE methods.

MAIN RESULTS

We included 18 RCTs involving 2952 participants; 15 compared rhCG with uhCG, and 3 compared rhLH with uhCG. The evidence for different comparisons ranged from very low to high quality: limitations were poor reporting of study methods and imprecision. Pharmaceutical companies funded 9 of the 18 studies, and 5 studies did not clearly report funding source. Ongoing pregnancy/live birthThere was no conclusive evidence of a difference between rhCG and uhCG (OR 1.15, 95% CI 0.89 to 1.49; 7 RCTs, N = 1136, I(2) = 0%, moderate quality evidence) or between rhLH and uhCG (OR 0.95, 95% CI 0.51 to 1.78, 2 RCTs, N = 289, I(2) = 0%, very low quality evidence) for ongoing pregnancy/live birth rates. OHSS There was no evidence of a difference between rhCG and uhCG in the incidence of OHSS: moderate to severe OHSS (OR 1.76, 95% CI 0.37 to 8.45; 3 RCTs, N = 417, I(2) = 0%, low quality evidence), moderate OHSS (OR 0.78, 95% CI 0.27 to 2.27; 1 RCT, N = 243, I(2) = 0%, low quality evidence), mild to moderate OHSS (OR 1.00, 95% CI 0.42 to 2.38; 2 RCTs, N = 320, I(2) = 0%, low quality evidence) or undefined OHSS (OR 1.18, 95% CI 0.50 to 2.78; 3 RCTs, N = 495, I(2) = 0%, low quality evidence). Likewise, there was no evidence of a difference between rhLH and uhCG in OHSS rates for moderate OHSS (OR 0.82, 95% CI 0.39 to 1.69, 2 RCTs, N = 280, I(2) = 5%, very low quality evidence). Other adverse events There was no evidence of a difference in miscarriage rates between rhCG and uhCG (OR 0.72, 95% CI 0.41 to 1.25; 8 RCTs, N = 1196, I(2) = 0%, low quality evidence) or between rhLH and uhCG (OR 0.95, 95% CI 0.38 to 2.40; 2 RCTs, N = 289, I(2) = 0%, very low quality evidence). For other adverse effects (most commonly injection-site reactions) rhCG was associated with a lower number of adverse events than uhCG (OR 0.52, 95% CI 0.35 to 0.76; 5 RCTS, N = 561; I(2) = 67%, moderate quality evidence). However, when we used a random-effects model due to substantial statistical heterogeneity, there was no evidence of a difference between the groups (OR 0.56, 95% CI 0.27 to 1.13). Only one study comparing rLH and uhCG reported other adverse events, and it was impossible to draw conclusions.

AUTHORS' CONCLUSIONS

We conclude that there is no evidence of a difference between rhCG or rhLH and uhCG for live birth or ongoing pregnancy rates or rates of OHSS.

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.

Assisted reproductive technology: an overview of Cochrane Reviews

BACKGROUND

As many as one in six couples will encounter problems with fertility, defined as failure to achieve a clinical pregnancy after regular intercourse for 12 months. Increasingly, couples are turning to assisted reproductive technology (ART) for help with conceiving and ultimately giving birth to a healthy live baby of their own. Fertility treatments are complex, and each ART cycle consists of several steps. If one of the steps is incorrectly applied, the stakes are high as conception may not occur. With this in mind, it is important that each step of the ART cycle is supported by good evidence from well-designed studies.

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews on procedures and treatment options available to couples with subfertility undergoing assisted reproductive technology (ART).

METHODS

Published Cochrane systematic reviews of couples undergoing ART (in vitro fertilisation or intracytoplasmic sperm injection) were eligible for inclusion in the overview. We also identified Cochrane reviews in preparation, for future inclusion.The outcomes of the overview were live birth (primary outcome), clinical pregnancy, multiple pregnancy, miscarriage and ovarian hyperstimulation syndrome (secondary outcomes). Studies of intrauterine insemination and ovulation induction were excluded.Selection of systematic reviews, data extraction and quality assessment were undertaken in duplicate. Review quality was assessed by using the AMSTAR tool. Reviews were organised by their relevance to specific stages in the ART cycle. Their findings were summarised in the text and data for each outcome were reported in 'Additional tables'.

MAIN RESULTS

Fifty-nine systematic reviews published in The Cochrane Library up to July 2015 were included. All were high quality. Thirty-two reviews identified interventions that were effective (n = 19) or promising (n = 13), 14 reviews identified interventions that were either ineffective (n = 2) or possibly ineffective (n = 12), and 13 reviews were unable to draw conclusions due to lack of evidence.An additional 11 protocols and five titles were identified for future inclusion in this overview.

AUTHORS' CONCLUSIONS

This overview provides the most up to date evidence on ART cycles from systematic reviews of randomised controlled trials. Fertility treatments are costly and the stakes are high. Using the best available evidence to optimise outcomes is best practice. The evidence from this overview could be used to develop clinical practice guidelines and protocols for use in daily clinical practice, in order to improve live birth rates and reduce rates of multiple pregnancy, cycle cancellation and ovarian hyperstimulation syndrome.

Prevention of Ovarian Hyperstimulation Syndrome: A Review

The following review aims to examine the available evidence to guide best practice in preventing ovarian hyperstimulation syndrome (OHSS). As it stands, there is no single method to completely prevent OHSS. There seems to be a benefit, however, in categorizing women based on their risk of OHSS and individualizing treatments to curtail their chances of developing the syndrome. At present, both Anti-Müllerian Hormone and the antral follicle count seem to be promising in this regard. Both available and upcoming therapies are also reviewed to give a broad perspective to clinicians with regard to management options. At present, we recommend the use of a "step-up" regimen for ovulation induction, adjunct metformin utilization, utilizing a GnRH agonist as an ovulation trigger, and cabergoline usage. A summary of recommendations is also made available for ease of clinical application. In addition, areas for potential research are also identified where relevant.

Best practices for controlled ovarian stimulation in in vitro fertilization

As applications for IVF have expanded over the years, so too have approaches to controlled ovarian stimulation (COS) for IVF. With this expansion and improved knowledge of basic reproductive biology, there is increasing interest in how COS practice influences IVF outcomes, and whether or not specific treatment scenarios call for personalized approaches to COS. For the majority of women undergoing COS and their treating physicians, the goal is to achieve a healthy live birth through IVF in a fresh cycle. Opinions on how COS strategy best leads to this common goal varies among centers as many clinicians base COS strategy not on evidence obtained through prospective randomized trials, but rather through observational studies and experience. Overall, when it comes to COS most clinicians recognize the approach should not be "one size fits all," but rather a patient-centered approach that takes the existing evidence into consideration. We outline the existing evidence for best practices in COS for IVF, highlighting how these practices may be incorporated into a patient-centered approach.

Assisted reproductive technology: an overview of Cochrane reviews

BACKGROUND

As many as one in six couples will encounter problems with fertility, defined as failure to achieve a clinical pregnancy after regular intercourse for 12 months. Increasingly, couples are turning to assisted reproductive technology (ART) for help with conceiving and ultimately giving birth to a healthy live baby of their own. Fertility treatments are complex, and each ART cycle consists of several steps. If one of the steps is incorrectly applied, the stakes are high as conception may not occur. With this in mind, it is important that each step of the ART cycle is supported by good evidence from well-designed studies.

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews on procedures and treatment options available to couples with subfertility undergoing assisted reproductive technology (ART).

METHODS

Published Cochrane systematic reviews of couples undergoing ART (in vitro fertilisation or intracytoplasmic sperm injection) were eligible for inclusion in the overview. We also identified Cochrane reviews in preparation, for future inclusion.The outcomes of the overview were live birth (primary outcome), clinical pregnancy, multiple pregnancy, miscarriage and ovarian hyperstimulation syndrome (secondary outcomes). Studies of intrauterine insemination and ovulation induction were excluded.Selection of systematic reviews, data extraction and quality assessment were undertaken in duplicate. Review quality was assessed by using the AMSTAR tool. Reviews were organised by their relevance to specific stages in the ART cycle. Their findings were summarised in the text and data for each outcome were reported in 'Additional tables'.

MAIN RESULTS

Fifty-eight systematic reviews published in The Cochrane Library were included. All were high quality. Thirty-two reviews identified interventions that were effective (n = 19) or promising (n = 13), 14 reviews identified interventions that were either ineffective (n = 3) or possibly ineffective (n=11), and 12 reviews were unable to draw conclusions due to lack of evidence.An additional 11 protocols and one title were identified for future inclusion in this overview.

AUTHORS' CONCLUSIONS

This overview provides the most up to date evidence on ART cycles from systematic reviews of randomised controlled trials. Fertility treatments are costly and the stakes are high. Using the best available evidence to optimise outcomes is best practice. The evidence from this overview could be used to develop clinical practice guidelines and protocols for use in daily clinical practice, in order to improve live birth rates and reduce rates of multiple pregnancy, cycle cancellation and ovarian hyperstimulation syndrome.

Gonadotropin therapy in assisted reproduction: an evolutionary perspective from biologics to biotech

Gonadotropin therapy plays an integral role in ovarian stimulation for infertility treatments. Efforts have been made over the last century to improve gonadotropin preparations. Undoubtedly, current gonadotropins have better quality and safety profiles as well as clinical efficacy than earlier ones. A major achievement has been introducing recombinant technology in the manufacturing processes for follicle-stimulating hormone, luteinizing hormone, and human chorionic gonadotropin. Recombinant gonadotropins are purer than urine-derived gonadotropins, and incorporating vial filling by mass virtually eliminated batch-to-batch variations and enabled accurate dosing. Recombinant and fill-by-mass technologies have been the driving forces for launching of prefilled pen devices for more patient-friendly ovarian stimulation. The most recent developments include the fixed combination of follitropin alfa + lutropin alfa, long-acting FSH gonadotropin, and a new family of prefilled pen injector devices for administration of recombinant gonadotropins. The next step would be the production of orally bioactive molecules with selective follicle-stimulating hormone and luteinizing hormone activity.

Assisted reproductive technology: an overview of Cochrane Reviews

BACKGROUND

As many as one in six couples will encounter problems with fertility, defined as failure to achieve a clinical pregnancy after regular intercourse for 12 months. Increasingly, couples are turning to assisted reproductive technology (ART) for help with conceiving and ultimately giving birth to a healthy live baby of their own. Fertility treatments are complex, and each ART cycle consists of several steps. If one of the steps is incorrectly applied, the stakes are high as conception may not occur. With this in mind, it is important that each step of the ART cycle is supported by good evidence from well-designed studies.

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews on procedures and treatment options available to couples with subfertility undergoing assisted reproductive technology (ART).

METHODS

Published Cochrane systematic reviews of couples undergoing ART (in vitro fertilisation or intracytoplasmic sperm injection) were eligible for inclusion in the overview. We also identified Cochrane reviews in preparation, for future inclusion.The outcomes of the overview were live birth (primary outcome), clinical pregnancy, multiple pregnancy, miscarriage and ovarian hyperstimulation syndrome (secondary outcomes). Studies of intrauterine insemination and ovulation induction were excluded.Selection of systematic reviews, data extraction and quality assessment were undertaken in duplicate. Review quality was assessed by using the AMSTAR tool. Reviews were organised by their relevance to specific stages in the ART cycle. Their findings were summarised in the text and data for each outcome were reported in 'Additional tables'.

MAIN RESULTS

Fifty-four systematic reviews published in The Cochrane Library were included. All were high quality. Thirty reviews identified interventions that were effective (n = 18) or promising (n = 12), 13 reviews identified interventions that were either ineffective (n = 3) or possibly ineffective (n=10), and 11 reviews were unable to draw conclusions due to lack of evidence.An additional 15 protocols and two titles were identified for future inclusion in this overview.

AUTHORS' CONCLUSIONS

This overview provides the most up to date evidence on ART cycles from systematic reviews of randomised controlled trials. Fertility treatments are costly and the stakes are high. Using the best available evidence to optimise outcomes is best practice. The evidence from this overview could be used to develop clinical practice guidelines and protocols for use in daily clinical practice, in order to improve live birth rates and reduce rates of multiple pregnancy, cycle cancellation and ovarian hyperstimulation syndrome.

Comparing the efficacy of urinary and recombinant hCG on oocyte/follicle ratio to trigger ovulation in women undergoing intracytoplasmic sperm injection cycles: a randomized controlled trial

PURPOSE

To compare the number of oocytes per follicles in ovulation induction with 10,000 IU urinary hCG (uhCG) and two different doses of recombinant hCG (rhCG) in women undergoing intracytoplasmic sperm injection (ICSI) cycles.

METHODS

This study was a prospective, randomized controlled trial which was performed on 180 primary infertile women undergoing ICSI cycles. All eligible patients underwent a standard GnRH-a long protocol. When at least two follicles reached a diameter of 18 mm, all patients were randomized to receive 10,000 IU urinary hCG or 250 μg recombinant hCG or 500 μg recombinant hCG for ovulation induction. Primary outcome measure included the number of oocytes retrieved per aspirated follicles. Secondary outcome measures were the number of oocytes retrieved, the number of mature oocytes, the number and quality of generated embryos, fertilization rate, implantation rate, chemical and clinical pregnancy rates and OHSS occurrence rate.

RESULTS

The mean number of retrieved oocytes per follicles were 71.82 ± 15.09, 69.84 ± 17.44 and 77.16 ± 17.61 in 10,000 IU uhCG, 250 μg rhCG and 500 μg rhCG, respectively which was significantly higher with 500 μg rhCG than the lower dose(P = .04). Other cycles and clinical outcomes were comparable between groups.

CONCLUSION

Recombinant hCG shows equivalent efficacy to urinary hCG in terms of the number of oocytes per aspirated follicles in selected patients undergoing ICSI; however, 500 μg rhCG seems to be more advantageous than the lower dose in this indication. Larger randomized trials are needed to generalize this strategy.

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.