Recurrent empty follicle syndrome successfully treated with recombinant human chorionic gonadotrophin

Genuine Empty Follicle Syndrome: Role of Double Trigger and Delayed Oocyte Retrieval (DTDO)

BACKGROUND

Empty follicle syndrome (EFS) is a condition of undetermined etiology where no oocytes are retrieved in an ART cycle despite adequate response to ovarian stimulation and diligent follicular aspiration. Because of the rarity of this condition, no much published strategies are available to tackle this.

AIM

The aim of this study was to evaluate whether sequential administration of gonadotropin-releasing hormone agonist (GnRHa) and human chorionic gonadotropin (hCG) as a trigger at 40 h and 36 h, respectively, before oocyte retrieval (OCR) could correct genuine empty follicle syndrome (GEFS).

STUDY SETTING AND DESIGN

This retrospective observational cohort study was conducted in a tertiary fertility center over a period of 6 years from January 2014 to December 2019. Patients with a history of GEFS were administered GnRHa and recombinant hCG subcutaneously at 40 h and 36 h, respectively, before OCR, i.e., double trigger and delayed oocyte retrieval (DTDO) (n = 13). The primary outcome measures studied were number of mature oocytes retrieved, oocyte maturation index (OMI), number of fertilized oocytes, and number of embryos available for embryo transfer. The secondary outcome measures were clinical pregnancy rate (CPR), miscarriage rate (MR) and live birth rate (LBR) per first frozen embryo transfer (FET) cycle, incidence of inadvertent premature ovulation, and ovarian hyperstimulation syndrome.

STATISTICAL ANALYSIS

Comparison between the groups was analysed by Fisher's exact test and paired t-test.

RESULTS

Patients in the DTDO group showed a significant improvement (P < 0.01) in the number of mature oocytes retrieved, OMI, number of fertilized oocytes, and number of embryos available for embryo transfer. In the first FET cycle, CPR (44.44%), LBR (44.44%), and MR (11.11%) were observed in the DTDO group.

CONCLUSION

Our findings implicate that double trigger and delayed OCR (DTDO) is a safe and efficacious treatment strategy for GEFS.

Does Double Dose of Recombinant Human Chorionic Gonadotropin for Final Follicular Maturation in In vitro Fertilization Cycles Improve Oocyte Quality: A Prospective Randomized Study

Context

In in vitro fertilization (IVF) cycles, the recommended dose of recombinant human chorionic gonadotropin (r-hCG), for triggering final follicular maturation is 250 μg, although there is some disagreement.

Aims

The aim of our study was to assess the effect on the number of mature oocytes retrieved after triggering ovulation in IVF cycles using 250 μg or 500 μg of r-hCG.

Settings and Design

Prospective, single-center, randomized study.

Subjects and Methods

100 women undergoing IVF with embryo transfer. The primary outcome measure was the total number of oocytes retrieved per follicle, number of mature oocytes, and number of embryos generated. The secondary outcomes included clinical and biochemical pregnancy rates and incidence of ovarian hyperstimulation syndrome.

Results

Mean number of oocytes retrieved (6.5 ± 4.0 vs. 6.4 ± 3.9, P = 0.3) and mean number of mature oocytes (4.0 ± 2.3 vs. 3.2 ± 2.3, P = 0.09) were similar in the two groups; however, mean number of oocytes retrieved per follicle was found to be higher with 500 μg r-hCG (67.4 ± 23.9 vs. 77.5 ± 23.3, P = 0.04). In the subgroup of poor responder women, there was a significant increase in the number of mature oocytes retrieved with double dose of r-hCG (2.2 ± 1.8 vs. 3.7 ± 1.9, P = 0.06), leading to improvement in fertilization and clinical pregnancy rates.

Conclusions

Double dose of r-hCG for final follicular maturation in IVF cycles resulted in improvement in mean number of oocytes per follicle but did not result in improved pregnancy rates in the women. In the subset of poor responders, 500 μg r-hCG seems to be more advantageous than the lower dose, although larger randomized trials are needed to generalize this strategy.

Compound heterozygous ZP1 mutations cause empty follicle syndrome in infertile sisters

Empty follicle syndrome (EFS) is a condition in which no oocyte is retrieved from mature follicles after proper ovarian stimulation in an in vitro fertilization procedure. Genetic evidence accumulates for the etiology of recurrent EFS without pharmacological or iatrogenic problems. In this study, we present two infertile sisters in a family with EFS after three cycles of standard ovarian stimulation with human chorionic gonadotrophin and/or gonadotropin-releasing hormone agonist therapy. Via whole-exome sequencing and cosegregation test, we identified compound heterozygous mutations in the gene of ZP1 in both of the infertile sisters. Coimmunoprecipitation tests and homology modeling analysis confirmed that both mutated ZP1 disrupt the formation of oocyte zona pellucida by interrupting the interaction among ZP1, ZP2, and ZP3. We thus propose that the specific mutations in ZP1 gene render a causality for the intractable EFS.

Human chorionic gonadotropin serum levels following ovulation triggering and IVF cycle outcome

PURPOSE

The clinical significance of serum hCG levels after ovulation triggering was studied previously with conflicting results. Our aim was to study the correlation of hCG levels on the day after ovulation triggering using recombinant hCG (r-hCG) with treatment outcome.

METHODS

A prospective observational study of all fresh IVF/ICSI cycles in a single medical center, between January 2015 and June 2016, was performed. hCG serum levels were obtained 10-12 h following ovulation triggering with 250 mcg r-hCG. Clinical and laboratory outcome parameters were compared between cycles with serum hCG above and below median level. A multivariate regression analysis was performed in order to study the association between hCG levels and live birth rate, after controlling for confounders.

RESULTS

Overall, 326 cycles were included. Median serum hCG level was 91.35 IU/L. hCG levels were lower as age and BMI were higher (p = 0.004, p < 0.001, respectively). The study groups did not differ with regard to clinical pregnancy rate (p = 0.14), live birth rate (p = 0.09), fertilization rate (p = 0.45), or metaphase II oocyte rate (p = 0.68). On multivariate regression analysis, hCG level was not associated with live birth (aOR 0.99, 95% CI 0.98-1.005), after controlling for patient's age and BMI.

CONCLUSIONS

hCG levels on the day after ovulation triggering with 250 mcg r-hCG are inversely correlated with patient age and BMI. However, they are not correlated with any clinical or laboratory outcome parameter. Therefore, testing for hCG levels after ovulation induction seems futile and cannot be recommended.

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.

Limitations in the process of transcription and translation inhibit recombinant human chorionic gonadotropin expression in CHO cells

Human chorionic gonadotropin (hCG) is a glycoprotein hormone that exists as a heterodimer with a α subunit and β subunit assembled together with disulfide bridges. This hormone plays an important role in the detection of ovulation induction and in the treatment of certain diseases that cause female infertility. The effects of transcription, subunit expression, assembling and secretion on recombinant hCG expression in CHO cells were studied using stable high-producing and low-producing cell lines generated by the FLP-In™ system. The results indicated that the mRNA and polypeptide levels of the β subunit were always higher than those of the α subunit. Further study confirmed that the differences were caused by the transcription rate rather than by mRNA stability. In the high-producing cell lines, there was obvious transcription level limitation of the α subunit in contrast to the β subunit. In addition, there was obvious limitation of the synthetic steps from mRNA to polypeptide for both the α subunit and the β subunit, especially the β subunit. Significant limitations of the assembly and secretion levels were not observed in this research. This study presents a research methodology for double subunit protein expression and provides valuable evidence for the enhancement of recombinant hCG productivity.

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.

Empty follicle syndrome: successful treatment in a recurrent case and review of the literature

Empty follicle syndrome is a condition in which no oocytes are retrieved after an apparently adequate ovarian response to stimulation and meticulous follicular aspiration. It is a rare condition of obscure etiology. A patient with primary infertility who underwent seven assisted reproductive technique cycles is described. In spite of a satisfactory ovarian response, aspiration yielded no oocytes in four cycles and 1-4 low quality oocytes in three cycles. In the index treatment cycle, ovulation was triggered using GnRH agonist 40 h prior to ovum pickup and hCG was added 6 h after the first trigger. Eighteen oocytes were recovered, of which 16 were mature and were inseminated by ICSI. Two embryos were transferred 48 h after aspiration and nine embryos were cryopreserved. The patient conceived and delivered a healthy boy at 38 weeks of gestation. The literature is reviewed and possible etiologies and treatment options of this enigmatic syndrome are suggested.

Differential effects of urinary and recombinant chorionic gonadotropin on oxidative stress responses in decidualizing human endometrial stromal cells

Human chorionic gonadotropin (hCG) is one of the earliest signals secreted by the implanting embryo. In addition to its well-known luteotropic function in early pregnancy, hCG also acts directly on decidualizing endometrium. Recently, we demonstrated that recombinant hCG (rhCG) prevented apoptosis in decidualizing human endometrial stromal cells (HESCs) exposed to oxidative stress. Two hCG preparations are widely used clinically: rhCG, produced by recombinant DNA technology, and urinay hCG (uhCG), extracted from urine of post-menopausal women. However, an analysis of the direct effects of rhCG and uhCG on the decidual phenotype of HESCs has not yet been done. In this study, we investigated the effects of uhCG and rhCG on the morphological and functional profiles of decidualizing HESCs. We demonstrate that neither rhCG nor uhCG alter the morphological appearance of the decidual HESC cultures, although rhCG but not uhCG attenuated prolactin expression, a major decidual marker protein. Moreover, rhCG, but not uhCG, protected decidualizing HESCs from oxidative cell death, mediated at least in part by two major mechanisms. First, rhCG, but not uhCG, enhances the expression of manganese superoxide dismutase, a cardinal enzyme in the cellular defense against oxidative damage. Second, rhCG signaling selectively limits activation of the apoptotic machinery in decidualizing HESCs by enhancing Bcl-2 expression whereas uhCG induces the expression of Fas ligand. Our results suggest that rhCG might be a preferable agent to protect the maternal decidua against oxidative damage in pregnancy, especially at the time of implantation and beyond.

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 (hCG) has been used to induce final oocyte maturation triggering in in vitro fertilization (IVF) and intra-cytoplasmic sperm injection (ICSI) cycles. Recombinant technology has allowed the production of two drugs that can be used for the same purpose, to mimic the endogenous luteinizing hormone (LH) surge. This allows commercial production to be adjusted according to market requirements; the removal of all urinary contaminants; and the safe subcutaneous administration of a compound with less batch-to-batch variation. However, prior to a change in practice the effectiveness of the recombinant drugs should be known compared to the currently used urinary human chorionic gonadotrophin (uhCG).

OBJECTIVES

To assess the efficacy and safety of subcutaneous recombinant hCG (rhCG) and high dose recombinant LH (rLH) compared with intramuscular uhCG for inducing final oocyte maturation triggering in IVF and ICSI cycles.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (January 2010), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010), MEDLINE (1966 to January 2010) and EMBASE (1980 to January 2010).

SELECTION CRITERIA

Two review authors independently scanned titles and abstracts and selected those that appeared relevant for collection of the full paper. Only truly 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 normo-gonadotropic women were included.

DATA COLLECTION AND ANALYSIS

Assessment for inclusion or exclusion, quality assessment and data extraction were performed independently by two authors. Discrepancies were discussed in the presence of a third author and consensus reached. Quality assessment included method of randomisation, allocation concealment, blinding of participants and assessors, reporting of a power calculation and intention-to-treat analysis.

MAIN RESULTS

Fourteen RCTs (n = 2306) were identified; 11 compared rhCG with uhCG and three compared rhLH with uhCG. There was no evidence of a statistically significant difference between rhCG and uhCG regarding the ongoing pregnancy or live birth rate (6 RCTs: OR 1.04, 95% CI 0.79 to 1.37; P = 0.83, I(2) = 0%). There was no significant difference in the incidence of ovarian hyperstimulation syndrome (OHSS) between rhCG and uhCG (3 RCTs: OR 1.5, 95% CI 0.37 to 4.1; P = 0.37, I(2) = 0%). There was no evidence of statistically significant difference between rhLH and uhCG regarding the ongoing pregnancy or live birth rate (OR 0.94, 95% CI 0.50 to 1.76) and incidence of OHSS (OR 0.82, 95% CI 0.39 to 1.69). These results leave open the possibility of strong differences in favour of either treatment for both ongoing pregnancy and OHSS.

AUTHORS' CONCLUSIONS

We conclude that there is no evidence of difference between rhCG or rhLH and uhCG in achieving final follicular maturation in IVF, with equivalent pregnancy rates and OHSS incidence. According to these findings uHCG is still the best choice for final oocyte maturation triggering in IVF and ICSI treatment cycles.

Recombinant HCG for triggering ovulation increases the rate of mature oocytes in women treated for ICSI

PURPOSE

To conduct a prospective randomized study in order to investigate the effect of recombinant HCG (rHCG) on oocyte nuclear and cytoplasm maturity compared to urinary HCG (uHCG), for inducing ovulation in women treated with ICSI for male factor infertility.

MATERIALS AND METHODS

We compared 89 patients randomly assigned to one of the two study groups. Group A consisted of 42 women who received a subcutaneous (s.c.) injection of 250 microg rHCG and group B consisted of 47 patients receiving an intramuscular (i.m.) injection of 10,000 IU uHCG.

RESULTS

Patients treated with rHCG showed a rate of metaphase II oocytes, a number of metaphase II oocytes with mature cytoplasm and a rate of metaphase II oocytes with mature cytoplasm calculated from total MII oocytes statistically higher than in patients treated with uHCG. However this differences were not associated with a significantly better clinical outcome.

CONCLUSION

Our data show that in women treated with ICSI for male factor infertility, rHCG increases the rate of metaphase II oocytes, the number and the rate of MII oocytes with mature cytoplasm compared to uHCG. A larger study comparing transfer cycles of embryos all derived from oocytes with mature cytoplasm and transfer cycles of embryos all derived from oocytes with immature cytoplasm may be needed to clarify clinical correlations.

Empty follicle syndrome: the reality of a controversial syndrome, a systematic review

OBJECTIVES

To examine all case reports and studies of empty follicle syndrome (EFS) that have been published since the condition was first reported, in an attempt to identify trends or common features that may expose possible risk or causative factors.

DESIGN

Systematic review of all available literature obtained from PubMed, Ovid, and Embase.

SETTING

Academic unit.

PATIENT(S)

Review of all published case reports and case studies.

INTERVENTION(S)

All original work was assessed and labeled as "genuine" or "false" EFS according to set definitions.

MAIN OUTCOME MEASURE(S)

Genuine and false EFS. We defined genuine EFS as a failure to retrieve oocytes from mature ovarian follicles after ovarian stimulation for IVF after apparently normal follicular development and steroidogenesis in the presence of optimal beta-hCG levels on the day of oocyte retrieval. False EFS included all cases in which this definition cannot apply and often in which human error or a pharmaceutical inaccuracy has occurred.

RESULT(S)

By classifying all cases of EFS as "genuine" or "false" according to stated definitions, it was evident that a much greater proportion of cases of reported EFS, 67%, occurred as a result of human error and that "genuine empty follicle syndrome" is an even rarer event than previously presumed.

CONCLUSION(S)

Our report highlights the value of classifying cases of EFS as "genuine" or "false" and shows that more epidemiological data are required of "genuine" EFS cases to develop a clearer picture of the possible etiology.

Oocytes in the empty follicle: a controversial syndrome

OBJECTIVE

To assess the prevalence and etiology of the empty follicle syndrome (EFS).

DESIGN

Observational longitudinal study.

SETTING

Tertiary fertility centers.

PATIENT(S)

All patients beginning in vitro fertilization (IVF) treatment from December 2002 to November 2004 were included. Couples undergoing IVF with donor oocytes or participating in an experimental IVF study were excluded from analysis.

INTERVENTION(S)

Identification of EFS cycles. Comparing ovarian hyperstimulation strategy, follicle count, and timing of human chorionic gonadotropin (hCG) for final oocyte maturation of the EFS cycles with normal IVF cycles.

MAIN OUTCOME MEASURE(S)

Number of follicles punctured, number of oocytes recovered, previous and future IVF attempts, and serum hormone levels.

RESULT(S)

Twenty-five of a total of 1,849 patients were identified with an EFS cycle. Reasons for occurrence of EFS cycles were mistiming of hCG for final oocyte maturation, premature ovulation, and poor ovarian response. None of the affected patients had experienced EFS cycles in earlier IVF attempts nor were there any recurrence in subsequent treatments.

CONCLUSION(S)

Accurate timing of induction of final oocyte maturation, properly scheduled ovarian hyperstimulation, instruction of patients and doctors, and full workup for IVF are essential for the successful recovery of oocytes. Occurrence of EFS in IVF can normally be attributed to a failure of at least one of these factors and probably rarely or never occurs otherwise.

Recombinant versus urinary human chorionic gonadotrophin for ovulation induction in assisted conception

BACKGROUND

For the last few decades urinary human chorionic gonadotrophin has been used to induce final follicular maturation and for triggering ovulation in assisted conception. Recombinant technology has allowed the production of two drugs that can be used for the same purpose: to mimic the endogenous luteinizing hormone (LH) surge. This would allow commercial production to be adjusted according to market requirements. In addition all urinary contaminants would also be removed. Hence, this would allow the safe subcutaneous administration of a compound with less batch-to-batch variation. However, prior to a change in practice, the effectiveness of the recombinant drugs should be known, compared to the currently used urinary human chorionic gonadotrophins.

OBJECTIVES

To assess the safety and efficacy of subcutaneous rhCG and high dose rLH compared with intramuscular uhCG for inducing final oocyte maturation and triggering ovulation.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (27 August 2003), the Cochrane Central Register of Controlled Trials (CENTRAL on The Cochrane Library, issue 4, 2003), MEDLINE (1966 to Feb 2004) and EMBASE (1980 to Feb 2004). Searches were not limited by language. The bibliographies of included, excluded trials and abstracts of major meetings were searched for additional trials. Authors and pharmaceutical companies were contacted for missing and unpublished data.

SELECTION CRITERIA

Two reviewers independently scanned titles and abstracts, and selected those that appeared relevant for collection of the full paper. Only truly randomised controlled trials comparing rhCG or high dose r-LH with urinary hCG for triggering ovulation in assisted conception for treatment of infertility in normogonadotrophic women were included.

DATA COLLECTION AND ANALYSIS

Assessment of inclusion/exclusion, quality assessment and data extraction were performed independently by at least two reviewers. Discrepancies were discussed in the presence of a third reviewer and a consensus reached. Quality assessment included method of randomisation, allocation concealment, blinding of participants and assessors, reporting of a power calculation, intention to treat analysis, and handling of dropouts. Data extraction included characteristics of participants, the intervention and control procedures, and outcomes.

MAIN RESULTS

Seven RCTs were identified, four comparing rhCG and uhCG and three comparing rhLH and uhCG. There was no statistically significant difference between rhCG vs uhCG regarding the ongoing pregnancy/ live birth rate (OR 0.98, 95% CI 0.69 to 1.39), pregnancy rate, miscarriage or incidence of OHSS. There was no statistically significant difference between rhLH vs uhCG regarding the ongoing pregnancy/ live birth rate (OR 0.94, 95% CI 0.50 to 1.76), pregnancy rate, miscarriage or incidence of OHSS. The manufacturer of rhLH has decided not to further develop this product. rhCG was associated with a reduction in the incidence of local site reactions and other minor adverse effects (OR 0.47, 95% CI 0.32 to 0.70).

AUTHORS' CONCLUSIONS

There is no evidence of difference in clinical outcomes between urinary and recombinant gonadotrophins for induction of final follicular maturation. Additional factors should be considered when choosing gonadotrophin type, including safety, cost and drug availability.

Poor oocyte retrieval is a manifestation of low ovarian reserve

Women with complete absence of oocytes during retrieval, as well as those with less than the 10th percentile of the expected number of oocytes retrieved, have clear manifestations of low ovarian reserve. It seems that this occurrence is a gradual biological phenomenon related to the basic pathophysiology of ovarian aging.

Unsuccessful oocyte retrieval: technical artefact or genuine 'empty follicle syndrome'?

Unsuccessful oocyte retrieval after apparently successful ovarian stimulation (also referred to as 'empty follicle syndrome') occurs in 1-7% of women undergoing assisted reproductive techniques. A literature review was performed, as individual studies have reached differing conclusions on the aetiology and treatment or management of the phenomenon. The aetiology is not clear, but probably multifactorial, and occurs in natural and stimulated cycles. In many cases, technical problems such as errors in human chorionic gonadotrophin (HCG) administration or defects in HCG batches can be identified, but this is not sufficient to account for all reported cases. The term empty follicle syndrome is inappropriate in cases in which such procedural factors can be identified. In many patients, however, unsuccessful oocyte retrieval appears to be due to an underlying ovarian dysfunction, and some may have a genuine empty follicle syndrome. Appropriate measures, such as monitoring of serum beta-HCG, should be taken to minimize the risk of unsuccessful oocyte retrieval. This review discusses the potential causes of unsuccessful oocyte retrieval, its clinical implications, and potential solutions to this clinical problem.

The empty follicle syndrome

The empty follicle syndrome (EFS) is characterized by the lack of retrieved oocytes from follicles after ovulation induction and apparently normal follicular development for in vitro fertilization, despite repeated aspiration and flushing. The underlying mechanism of the EFS remains hypothetical. Some Authors have suggested that it is related to the "cause" leading to female infertility, whereas others have pointed to the alternative suggestion that it might reflect dysfunctional folliculogenesis, with early oocyte atresia and apparently normal hormonal response. Moreover, some Authors believe that the EFS does not exist, and that the oocyte retrieval failure is a pharmacological fault. The risk of recurrence is higher as the age of the patients increases. The EFS cannot be predicted by the pattern of ovarian response to stimulation either sonographically or hormonally. Consequently, the diagnosis of EFS is retrospective. Whatever the underlying cause of an EFS cycle, patients with an EFS cycle should be counselled regarding the possibility of recurrence of such an event in future cycles.

Comparative Use of Urinary and Recombinant Human Chorionic Gonadotropins in Women

Human chorionic gonadotropin (hCG) preparations have been widely used as a surrogate for the mid-cycle luteinizing hormone (LH) surge for several decades. The urinary source of hCG preparations was favored for many years because of the easy collection of the starting material. However, the final structure of these urinary-derived preparations appears to be quite different from the natural placenta product. Furthermore, many disadvantages of these commercial preparations have been reported, such as local adverse events and immunologic reactions. The recent advent of recombinant DNA technology has now made recombinant hCG (r-hCG) available. This new product ensures high purity and batch-to-batch consistency. The pharmacokinetic and pharmacodynamic profiles of both urinary and recombinant preparations are quite similar. In clinical practice, several trials have been performed to compare both the efficacy and safety of urinary hCG (u-hCG) and r-hCG preparations. Overall, the reported data show that r-hCG preparations are at least as effective as u-hCG products in reproducing the follicular events surrounding the endogenous LH surge. Moreover, the r-hCG products ensure a better hormonal environment during the luteal phase. Finally, the overall tolerability of r-hCG preparations has been shown to be much better than that of u-hCG preparations. As a consequence, the newly available r-hCG preparations offer the first opportunity for clinicians to treat anovulatory women with a full range of recombinant products.

The combination of urinary and recombinant HCG improves outcome in patients with decreased oocyte/follicle ratio in previous cycles

This report describes three cases in which the addition of recombinant HCG to urinary HCG to trigger ovulation in IVF improved oocyte recovery in patients with a history of scant oocyte yield in previous cycles.

Use of recombinant human chorionic gonadotropin in ovulation induction

To review the use of hCG and to describe the clinical benefit of recombinant hCG (r-hCG) based on the published results of prospective, randomized studies. Review of published articles. Tertiary infertility care center.None.None. Oocyte number and quality, luteal phase progesterone, pregnancy and OHSS rate, and local tolerability. The published data consistently show that single doses of 250 microg r-hCG and 5,000 IU urinary (u)-hCG produce similar clinical outcomes when used in infertility treatment cycles for timed intercourse, IUI, and IVF in terms of the number of oocytes retrieved, number of mature oocytes harvested, and fertilization and pregnancy rates attained. Single doses of 10,000 IU u-hCG also gave results comparable to single doses of 250 microg r-hCG. P levels in the midluteal phase were significantly higher with the use of r-hCG compared with u-hCG, and local injection site adverse effects were significantly less frequent, demonstrating the higher purity of the recombinant product. A single 500-microg dose of r-hCG led to a higher rate of ovarian hyperstimulation syndrome compared with a 250-microg dose, with no significant improvement in pregnancy rates.A single dose of 250 microg r-hCG was at least as effective as single doses of 5,000 or 10,000 IU u-hCG but offered the advantages associated with use of a recombinant product: local injection site adverse effects were significantly less frequent with r-hCG than with u-hCG.

Recombinant human chorionic gonadotropin (rhCG) in assisted reproductive technology: results of a clinical trial comparing two doses of rhCG (Ovidrel) to urinary hCG (Profasi) for induction of final follicular maturation in in vitro fertilization-embryo transfer

OBJECTIVE

To compare the efficacy and safety of 250 microg and 500 microg of recombinant hCG with 10,000 U USP of urinary hCG in assisted reproduction technology.

DESIGN

Open, comparative, randomized, prospective clinical study.

SETTING

Twenty tertiary care U.S. infertility centers.

PATIENT(S)

Two hundred ninety-seven ovulatory infertile women undergoing a single cycle of assisted reproduction technology.

INTERVENTION(S)

Patients were randomized 1:1:1 to 250 microg of recombinant hCG SC, 500 microg of recombinant hCG SC, or 10,000 U USP urinary hCG IM after completing gonadotropin stimulation.

MAIN OUTCOME MEASURE(S)

Number of oocytes retrieved per patient receiving hCG. Also, measures of oocyte maturity, embryo development, and luteal function, as well as pregnancy and pregnancy outcome. Adverse safety events, laboratory changes, local tolerance, and immunogenicity were also assessed.

RESULT(S)

Mean numbers of oocytes retrieved per treatment group were equivalent, 13.6, 14.6, and 13.7 with 250 microg of recombinant hCG, 500 microg of recombinant hCG, and urinary hCG, respectively. The numbers of 2PN fertilized oocytes on day 1 after oocyte retrieval, and 2PN or cleaved embryos on the day of embryo transfer, were significantly higher with 500 microg of recombinant hCG than with the lower dose. However, the incidence of adverse events also tended to be higher with this dose.

CONCLUSION(S)

Recombinant hCG is effective and well tolerated in the induction of final follicular maturation and luteinization in women undergoing assisted reproduction technology. Recombinant hCG (250 microg) SC is equivalent to 10,000 U USP of urinary hCG in this indication.

Induction of ovulation in World Health Organization group II anovulatory women undergoing follicular stimulation with recombinant human follicle-stimulating hormone: a comparison of recombinant human chorionic gonadotropin (rhCG) and urinary hCG

OBJECTIVE

To compare the safety and efficacy of 250 microg recombinant hCG (rhCG) and 5,000 IU urinary hCG (uhCG), both administered s.c., for ovulation induction in anovulatory/oligo-ovulatory patients after follicular stimulation with recombinant hFSH (rhFSH).

DESIGN

Phase III, double-blind, double-dummy, randomized, parallel-group, multicenter study.

SETTING

Nineteen academic and private tertiary care infertility centers in Europe, Israel, Canada, and Australia.

PATIENT(S)

One hundred ninety-eight WHO group II anovulatory women, aged 20 to 38 years.

INTERVENTION(S)

Women were randomized to receive rhCG or uhCG after follicular stimulation with rhFSH in a chronic low-dose protocol. Blood samples were collected and ultrasound examinations performed during stimulation and after hCG administration.

MAIN OUTCOME MEASURE(S)

Ovulation (midluteal serum progesterone > or =30 nmol/L), serum progesterone, hCG levels after hCG, pregnancy, adverse events, local tolerability, and ovarian hyperstimulation syndrome (OHSS) incidence.

RESULT(S)

Ovulation rates did not differ between groups: 95.3% for rhCG (n = 85) and 88.0% for uhCG (n = 92). The one-sided 95% confidence interval for the observed difference fell above the predefined limit of -20%, indicating equivalence. Treatment was well tolerated, but more uhCG patients reported local reactions (particularly inflammation and pain) (P=.0001; logistic regression).

CONCLUSION(S)

Subcutaneous rhCG and uhCG show equivalent efficacy in ovulation induction; however, rhCG is better tolerated.