Ovarian hyperstimulation syndrome: a clinical report on 4894 consecutive ART treatment cycles

BACKGROUND

Although a large number of studies have been dedicated to ovarian hyperstimulation syndrome (OHSS) none gave full embryological and clinical outcomes comparing oocyte trigger with human chorionic gonadotrophin (HCG) versus with a gonadotrophin-releasing hormone (GnRH) agonist (Buserelin) in cases with suspicious OHSS. The aim of the present study was thus to analyze 4894 consecutive assisted reproductive treatment cycles to undercover associated risk factors for development of OHSS, and the effects of the use of Buserelin as ovulation trigger on embryological and clinical outcomes.

METHODS

In the 51 cases that developed OHSS, ovulation trigger was performed with HCG as indicators were not suspicious for OHSS. These were compared against two types of groups: 71 cases where Buserelin was used for ovulation induction due to suspicious development of OHSS; and those remaining 4772 cases where ovulation trigger was currently performed with HCG (control).

RESULTS

Of the cases treated with Buserelin the oocyte maturation rate and the ongoing pregnancy rate were significantly lower, with higher rates of ectopic pregnancy and newborn malformations, but none developed OHSS. Of the OHSS cases, 23 needed hospitalization, with no major complications.

CONCLUSIONS

Young age, lower time of infertility, lower basal follicle stimulating hormone levels, higher number of cases with female factor and polycystic ovarian syndrome, high number of follicles and higher estradiol concentrations were the risk factors found associated with OHSS. Cases with OHSS also presented higher follicle count but the estradiol levels were within the normal range. It thus remains to develop more strict criteria to avoid all cases with OHSS.

Ovarian hyperstimulation syndrome after gonadotropin-releasing hormone agonist triggering and "freeze-all": in-depth analysis of genetic predisposition

PURPOSE

We report on the results of the whole-genome analysis performed in a patient who developed severe ovarian hyperstimulation syndrome (OHSS) following gonadotropin-releasing hormone (GnRH) agonist triggering in a "freeze-all" protocol.

METHODS

A 30-year-old patient with polycystic ovary syndrome who developed severe early-onset OHSS with clinical ascites, and slight renal and hepatic dysfunction was admitted for monitoring and treatment with cabergoline and intravenous albumin. Exome sequencing to assess for any known genetic predisposition for OHSS was performed.

RESULTS

No known genetic variants associated with OHSS predisposition were found.

CONCLUSIONS

Case reports of severe OHSS following a "freeze-all" strategy are starting to arise, showing that OHSS has not been completely eliminated with this approach. Further studies should be conducted to confirm if such cases may be due to genetic predisposition or not.

Gonadotropin-releasing hormone agonist triggering is effective, even at a low dose, for final oocyte maturation in ART cycles: Case series

OBJECTIVE

To investigate the efficacy of low-dose gonadotropin-releasing hormone (GnRH) agonist for final oocyte maturation in females undergoing assisted reproductive treatment (ART) cycles.

MATERIAL AND METHODS

Nine females undergoing ovarian stimulation in a GnRH antagonist protocol who received triptorelin 0.1 mg to trigger final oocyte maturation were included. Treatment outcomes of these patients were compared with those of controls, matched for age and oocyte number (n=14), who received 0.2 mg triptorelin at the same time. The luteal phase was supported with vaginal micronized progesterone and oral estradiol hemihydrate 2 mg twice daily.

RESULTS

The mean (±) numbers of retrieved, metaphase II, and fertilized oocytes were 15.66±7.82, 14±7.28, and 10.11±5.86, respectively. The implantation and clinical pregnancy rates were 46.1% and 71.4%, respectively. Of the pregnancies, 2 were live births, 1 was a preterm birth (twins), 2 are on-going, and 2 ended as miscarriages. No case of OHSS was encountered. On comparison of the results of these patients (fresh cycles; n=7) with those of matched controls, there were no significant differences in terms of retrieved mature oocytes, implantation rates, or clinical pregnancy rates (p>0.05).

CONCLUSION

These findings suggest that low-dose GnRH agonist triggering has similar efficacy as standard doses in terms of retrieved mature oocytes and clinical pregnancy rates in in vitro fertilization cycles.

Use of gonadotropin-releasing hormone agonist trigger during in vitro fertilization is associated with similar endocrine profiles and oocyte measures in women with and without polycystic ovary syndrome

OBJECTIVE

To compare endocrine profiles and IVF outcomes after using GnRH agonists (GnRHa) to trigger final oocyte maturation in women with polycystic ovary syndrome (PCOS) with other hyper-responders.

DESIGN

Retrospective cohort study.

SETTING

Academic center.

PATIENT(S)

Forty women with PCOS and 74 hyper-responders without PCOS.

INTERVENTION(S)

GnRHa trigger.

MAIN OUTCOME MEASURE(S)

Number of oocytes.

RESULT(S)

Serum E2, LH, and P levels on the day of GnRHa trigger and the day after trigger did not differ significantly between groups. There were no significant differences in total number of oocytes or percent mature oocytes obtained between groups after controlling for age, antral follicle count, and total days of stimulation. The overall rate of no retrieval of oocytes after trigger was low (2.6%). Fertilization, implantation, clinical pregnancy, and live-birth rates were similar in the two groups. No patients developed ovarian hyperstimulation syndrome (OHSS).

CONCLUSION(S)

The similar post-GnRHa trigger hormone profiles and mature oocyte yield support the routine use of GnRHa trigger to prevent OHSS in women with PCOS.

Gonadotropin-releasing hormone agonist versus HCG for oocyte triggering in antagonist-assisted reproductive technology

BACKGROUND

Human chorionic gonadotropin (HCG) is routinely used for final oocyte maturation triggering in in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) cycles, but the use of HCG for this purpose may have drawbacks. Gonadotropin-releasing hormone (GnRH) agonists present an alternative to HCG in controlled ovarian hyperstimulation (COH) treatment regimens in which the cycle has been down-regulated with a GnRH antagonist. This is an update of a review first published in 2010.

OBJECTIVES

To evaluate the effectiveness and safety of GnRH agonists in comparison with HCG for triggering final oocyte maturation in IVF and ICSI for women undergoing COH in a GnRH antagonist protocol.

SEARCH METHODS

We searched databases including the Menstrual Disorders and Subfertility Group (MDSG) Specialised Register of Controlled Trials, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO, the Cumulative Index to Nursing and Allied Health Literature (CINAHL) and trial registers for published and unpublished articles (in any language) on randomised controlled trials (RCTs) of gonadotropin-releasing hormone agonists versus HCG for oocyte triggering in GnRH antagonist IVF/ICSI treatment cycles. The search is current to 8 September 2014.

SELECTION CRITERIA

RCTs that compared the clinical outcomes of GnRH agonist triggers versus HCG for final oocyte maturation triggering in women undergoing GnRH antagonist IVF/ICSI treatment cycles were included.

DATA COLLECTION AND ANALYSIS

Two or more review authors independently selected studies, extracted data and assessed study risk of bias. Treatment effects were summarised using a fixed-effect model, and subgroup analyses were conducted to explore potential sources of heterogeneity. Treatment effects were expressed as mean differences (MDs) for continuous outcomes and as odds ratios (ORs) for dichotomous outcomes, together with 95% confidence intervals (CIs). Primary outcomes were live birth and rate of ovarian hyperstimulation syndrome (OHSS) per women randomised. Grades of Recommendation, Assessment, Development and Evaluation (GRADE) methods were used to assess the quality of the evidence for each comparison.

MAIN RESULTS

We included 17 RCTs (n = 1847), of which 13 studies assessed fresh autologous cycles and four studies assessed donor-recipient cycles. In fresh autologous cycles, GnRH agonists were associated with a lower live birth rate than was seen with HCG (OR 0.47, 95% CI 0.31 to 0.70; five RCTs, 532 women, I(2) = 56%, moderate-quality evidence). This suggests that for a woman with a 31% chance of achieving live birth with the use of HCG, the chance of a live birth with the use of an GnRH agonist would be between 12% and 24%.In women undergoing fresh autologous cycles, GnRH agonists were associated with a lower incidence of mild, moderate or severe OHSS than was HCG (OR 0.15, 95% CI 0.05 to 0.47; eight RCTs, 989 women, I² = 42%, moderate-quality evidence). This suggests that for a woman with a 5% risk of mild, moderate or severe OHSS with the use of HCG, the risk of OHSS with the use of a GnRH agonist would be between nil and 2%.In women undergoing fresh autologous cycles, GnRH agonists were associated with a lower ongoing pregnancy rate than was seen with HCG (OR 0.70, 95% CI 0.54 to 0.91; 11 studies, 1198 women, I(2) = 59%, low-quality evidence) and a higher early miscarriage rate (OR 1.74, 95% CI 1.10 to 2.75; 11 RCTs, 1198 women, I² = 1%, moderate-quality evidence). However, the effect was dependent on the type of luteal phase support provided (with or without luteinising hormone (LH) activity); the higher rate of pregnancies in the HCG group applied only to the group that received luteal phase support without LH activity (OR 0.36, 95% CI 0.21 to 0.62; I(2) = 73%, five RCTs, 370 women). No evidence was found of a difference between groups in risk of multiple pregnancy (OR 3.00, 95% CI 0.30 to 30.47; two RCTs, 62 women, I(2) = 0%, low-quality evidence).In women with donor-recipient cycles, no evidence suggested a difference between groups in live birth rate (OR 0.92, 95% CI 0.53 to 1.61; one RCT, 212 women) or ongoing pregnancy rate (OR 0.88, 95% CI 0.58 to 1.32; three RCTs, 372 women, I² = 0%). We found evidence of a lower incidence of OHSS in the GnRH agonist group than in the HCG group (OR 0.05, 95% CI 0.01 to 0.28; three RCTs, 374 women, I² = 0%).The main limitation in the quality of the evidence was risk of bias associated with poor reporting of methods in the included studies.

AUTHORS' CONCLUSIONS

Final oocyte maturation triggering with GnRH agonist instead of HCG in fresh autologous GnRH antagonist IVF/ICSI treatment cycles prevents OHSS to the detriment of the live birth rate. In donor-recipient cycles, use of GnRH agonists instead of HCG resulted in a lower incidence of OHSS, with no evidence of a difference in live birth rate.Evidence suggests that GnRH agonist as a final oocyte maturation trigger in fresh autologous cycles is associated with a lower live birth rate, a lower ongoing pregnancy rate (pregnancy beyond 12 weeks) and a higher rate of early miscarriage (less than 12 weeks). GnRH agonist as an oocyte maturation trigger could be useful for women who choose to avoid fresh transfers (for whatever reason), women who donate oocytes to recipients or women who wish to freeze their eggs for later use in the context of fertility preservation.

Retrospective comparison of GnRH agonist trigger with HCG trigger in GnRH antagonist cycles in anticipated high-responders

All IVF-ICSI cycles carried out between October 2009 and October 2012 using GnRH agonist (GnRHa) ovulation trigger (n = 62) followed by a single dose of HCG plus progesterone and oestradiol in the luteal phase because of anticipated ovarian hypertsimulation were retrospectively compared with historic control cycles using HCG trigger (n = 29) and standard luteal phase support. Women's mean age, body mass index, anti-Müllerian hormone, FSH, LH, starting and total stimulation dose, number of follicles, oocytes, embryos, fertilization, implantation, polycystic ovary syndrome, ICSI, live birth and ongoing pregnancy rates per embryo transfer were similar (GnRHa 40.7% versus HCG 35.0%). For each started cycle, GnRHa resulted in 11.4% higher (statistically non-significant) live birth and ongoing pregnancy rate (OR 1.73, CI 0.64 to 4.69), with a similar difference for double-embryo transfers (OR 1.62, CI 0.44 to 6.38) and less need for freezing all embryos (9.7% versus 27.6%; P = 0.04). Incidence of mild-to-moderate OHSS was 16.2% with GnRHa trigger and 31.0% with HCG trigger) and no severe OHSS in the former. The addition of single low-dose HCG in the luteal phase after GnRHa trigger for suspected high-responders reduced the incidence of OHSS with good clinical outcomes, compared with HCG trigger.

The risk of ectopic pregnancy following GnRH agonist triggering compared with hCG triggering in GnRH antagonist IVF cycles

PURPOSE

The aim of this study was to compare the incidence of ectopic pregnancy in GnRH agonist triggered IVF cycles with intensive luteal support versus hCG triggered IVF cycles.

METHODS

This study was conducted as a retrospective cohort analysis of women who underwent IVF treatment employing GnRH agonist or recombinant hCG (rhCG) triggers during 2-year period. The medical charts of women who achieved pregnancies were reviewed and their demographic characteristics, infertility reasons and IVF data were recorded. A multiple logistic regression analysis was performed to estimate the association between the triggering medication used to stimulate final oocyte maturation (GnRHa or rhCG) and EP, with adjustment for important confounders: the day of embryo transfer (ETD), the etiology of infertility and estrogen level at the time of triggering.

RESULTS

The number of metaphase II oocytes, fertilized oocytes and good quality embryos were significantly higher in the GnRH agonist triggered group compared with the hCG triggered group (p < 0.001 for all). The clinical pregnancy and implantation rates in the hCG triggered cycles were 38.6 and 31.1 %, respectively and 24.7 and 22 %, respectively in the triptorelin triggered cycles. The ectopic pregnancy rates were 5.3 % in the triptorelin triggered group and 1.4 % in the hCG triggered group. The trigger medication and the day of embryo transfer were found to have a significant effect on the probability of developing ectopic pregnancy (p = 0.028, p = 0.046 respectively). However, the estrogen level was not found to have a significant effect on the probability of developing ectopic pregnancy (p = 0.447).

CONCLUSIONS

The reasons for higher ectopic pregnancy rates in GnRH agonist triggered cycles relative to hCG triggered cycles may be the decreased receptivity of the endometrium due to insufficient luteal support and higher implantation potential of embryos in correlation with a higher number of good quality embryos obtained in these cycles.

Antagonist rescue of agonist IVF cycle at risk of OHSS: a case series

We describe a series of in vitro fertilisation (IVF) long protocol cycles presenting a risk of ovarian hyperstimulation syndrome (OHSS) which were rescued with an antagonist at a university-based tertiary-care fertility centre. Nineteen IVF patients presenting a risk of OHSS during treatment with long protocol, between 2009 and November 2012 were included in the present study. After discussion of available options, the agonist was stopped and a daily gonadotropin-releasing hormone (GnRH) antagonist injection was initiated ("rescue protocol") and maintained until ovulation trigger. Fourteen patients were triggered with human chorionic gonadotropin (hCG) and five with GnRH agonist bolus, yielding competent oocytes. Seventeen embryo transfers were performed in the fresh cycles. One patient developed moderate OHSS. There were eight clinical pregnancies after the fresh IVF cycle (42% per patient), and six further pregnancies after frozen-thawed cycles, resulting in a 73% cumulative clinical pregnancy rate within one year. We conclude that the "rescue protocol with antagonist" of the long IVF cycle with a high risk of OHSS allows us to carry on with the cycle, without compromising its success or the patient safety, thus broadening the possibility of applying the long protocol.

The current challenges to efficient immature oocyte cryopreservation

Oocyte cryopreservation represents an important tool for assisted reproductive technology. It offers the opportunity to preserve fertility in women at risk of loss of the ovarian function for various pathologies. It also represents a treatment alternative for couples that cannot benefit from embryo cryopreservation because of moral, religious, or legal constrains. On the other hand, in vitro oocyte maturation has a range of applications. It can be applied in patients with a contraindication to ovarian stimulation to prevent ovarian hyperstimulation syndrome or to eliminate the risk of stimulation of hormone-sensitive tumours in cancer patients. However, while mature oocyte cryopreservation has found wide-spread application and oocyte in vitro maturation has a place for the treatment of specific clinical conditions, data on the efficiency of freezing of immature or in vitro matured oocytes are poorer. In this review we will focus on the combination of oocyte in vitro maturation with oocyte cryopreservation with particular emphasis on the biological implications of the cryopreservation of immature or in vitro matured oocytes. The two cryopreservation approaches, slow freezing and vitrification, will be discussed in relation to possible cryodamage occurring to subcellular structures of the oocyte and the functional interaction between oocyte and cumulus cells.