Luteal phase defects following agonist-triggered ovulation: a patient-dependent response

Triggering of ovulation for GnRH-antagonist cycles in normal and low ovarian responders undergoing IVF/ICSI: A systematic review and meta-analysis of randomized trials

OBJECTIVE

To conduct a systematic review andmeta-analysis of all randomized controlled trials (RCTs) that investigated whether dual triggering [a combination of gonadotropin-releasing hormone (GnRH) agonist and human chorionic gonadotropin (hCG)] of final oocyte maturation can improve the number of oocytes retrieved and clinical pregnancy rate in low or normal responders undergoing in-vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles using a GnRH-antagonist protocol.

STUDY DESIGN

Studies up to October 2022 were identified from PubMed, Scopus, Cochrane Library and Web of Science. The risk of bias of included studies was assessed. Dichotomous outcomes were reported as relative risks (RR), and continuous outcomes were reported as weighted mean differences (WMD) with 95% confidence intervals (CI). The primary outcomes were number of oocytes retrieved, number of mature [metaphase II (MII)] oocytes, clinical pregnancy rate and ongoing pregnancy rate; other IVF outcomes were considered as secondary outcomes.

RESULTS

Seven studies were identified, and 898 patients were eligible for inclusion in this meta-analysis. The results showed that the number of oocytes retrieved [WMD = 1.38 (95% CI 0.47-2.28), I2 = 66%, p = 0.003, low evidence], number of MII oocytes [WMD = 0.7 (95% CI 0.35-1.05), I2 = 42%, p < 0.0001, moderate evidence], number of embryos [WMD = 0.68 (95% CI 0.07-1.3), I2 = 67%, p = 0.03, low evidence] and number of good-quality embryos [WMD = 1.14 (95% CI 0.35-1.93), I2 = 0%, p = 0.005, moderate evidence] in the dual trigger group were significantly higher than in the hCG trigger group. The results of the ovarian response subgroup analysis showed significant differences in all of these outcomes in normal responders, and no differences in any of the outcomes in low responders, except for the number of MII oocytes. In low responders, clinical pregnancy rates may be improved in the dual trigger group [RR = 2.2 (95% CI 1.05-4.61), I2 = 28%, p = 0.04, low evidence].

CONCLUSION

Dual triggering by GnRH agonist and hCG improved oocyte maturity and embryo grading for normal responders in GnRH-antagonist cycles. Dual triggering for final oocyte maturation may improve clinical pregnancy rates in low responders.

Luteal Phase in Assisted Reproductive Technology

Luteal phase (LP) is the period of time beginning shortly after ovulation and ending either with luteolysis, shortly before menstrual bleeding, or with the establishment of pregnancy. During the LP, the corpus luteum (CL) secretes progesterone and some other hormones that are essential to prepare the uterus for implantation and further development of the embryo, the function known as uterine receptivity. LP deficiency (LPD) can occur when the secretory activity of the CL is deficient, but also in cases of normal CL function, where it is caused by a defective endometrial response to normal levels of progesterone. LPD is particularly frequent in treatments using assisted reproductive technology (ART). Controlled ovarian stimulation usually aims to obtain the highest number possible of good-quality oocytes and requires the use of gonadotropin-releasing hormone (GnRH) analogs, to prevent premature ovulation, as well as an ovulation trigger to achieve timed final oocyte maturation. Altogether, these treatments suppress pituitary secretion of luteinizing hormone (LH), required for the formation and early activity of the CL. In addition to problems of endometrial receptivity for embryos, LPD also leads to dysfunction of the local uterine immune system, with an increased risk of embryo rejection, abnormally high uterine contractility, and restriction of uterine blood flow. There are two alternatives of LPD prevention: a direct administration of exogenous progesterone to restore the physiological progesterone serum concentration independently of the CL function, on the one hand, and treatments aimed to stimulate the CL activity so as to increase endogenous progesterone production, on the other hand. In case of pregnancy, some kind of LP support is often needed until the luteal-placental shift occurs. If LPD is caused by defective response of the endometrium and uterine immune cells to normal concentrations of progesterone, a still poorly defined condition, symptomatic treatments are the only available solution currently available.

Is oocyte maturation rate associated with triptorelin dose used for triggering final oocyte maturation in patients at high risk for severe ovarian hyperstimulation syndrome?

STUDY QUESTION

Are oocyte maturation rates different among 0.1, 0.2 and 0.4 mg triptorelin used for triggering final oocyte maturation in patients at high risk for ovarian hyperstimulation syndrome (OHSS) undergoing ICSI?

SUMMARY ANSWER

A dose of 0.1 mg triptorelin results in similar oocyte maturation rates compared to higher doses of 0.2 and 0.4 mg in patients at high risk for OHSS undergoing ICSI.

WHAT IS KNOWN ALREADY

The GnRH agonist triptorelin is widely used instead of hCG for triggering final oocyte maturation, in order to eliminate the risk of severe OHSS in patients undergoing ovarian stimulation for IVF/ICSI. However, limited data are currently available regarding its optimal dose use for this purpose in patients at high risk for OHSS.

STUDY DESIGN, SIZE, DURATION

A retrospective study was performed between November 2015 and July 2017 in 131 infertile patients at high risk for severe OHSS undergoing ovarian stimulation for ICSI. High risk for severe OHSS was defined as the presence of at least 19 follicles ≥11 mm in diameter on the day of triggering final oocyte maturation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Ovarian stimulation was performed with recombinant FSH and GnRH antagonists. Patients received 0.1 (n = 42), 0.2 (n = 46) or 0.4 mg (n = 43) triptorelin for triggering final oocyte maturation. Hormonal evaluation of FSH, LH, estradiol (E2) and progesterone (PRG) was carried out on the day of triggering final oocyte maturation, 8 and 36 hours post triggering and 3, 5, 7, and 10 days after triptorelin administration. During this period, all patients were assessed for symptoms and signs indicative of severe OHSS development. Primary outcome measure was oocyte maturation rate, defined as the number of metaphase II (MII) oocytes divided by the number of cumulus-oocyte-complexes retrieved per patient. Results are expressed as median (interquartile range).

MAIN RESULTS AND THE ROLE OF CHANCE

No significant differences in patient baseline characteristics were observed among the 0.1 mg, the 0.2 mg and the 0.4 mg groups. Regarding the primary outcome measure, no differences were observed in oocyte maturation rate among the three groups compared [82.6% (17.8%) versus 83.3% (18.8%) versus 85.1% (17.2%), respectively, P = 0.686].In addition, no significant differences were present among the 0.1 mg, 0.2 mg and 0.4 mg groups, regarding the number of mature (MII) oocytes [21 (13) versus 20 (6) versus 20 (11), respectively; P = 0.582], the number of oocytes retrieved [25.5 (13) versus 24.5 (11) versus 23 (12), respectively; P = 0.452], oocyte retrieval rate [81.0% (17.7%) versus 76.5% (23.5%) versus 75.0% (22.5), respectively; P = 0.088], the number of fertilized (two pronuclei) oocytes [12.5 (9) versus 14.5 (7) versus 14.0 (8), respectively; P = 0.985], fertilization rate [71.7% (22%) versus 77.1% (19.1%) versus 76.6% (23.3%), respectively; P = 0.525] and duration of luteal phase [7 (1) versus 8 (2) versus 7 (1) days, respectively; P = 0.632]. Moreover, no significant differences were present among the three triptorelin groups regarding serum levels of LH, FSH, E2 and PRG at any of the time points assessed following triggering of final oocyte maturation.

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective study, and although there were no differences in the baseline characteristics of the three groups compared, the presence of bias cannot be excluded.

WIDER IMPLICATIONS OF THE FINDINGS

Based on the results of the current study, it appears that triggering final oocyte maturation with a lower (0.1 mg) or a higher dose (0.4 mg) of triptorelin, as compared to the most commonly used dose of 0.2 mg, does not confer any benefit in terms of oocyte maturation rate in patients at high risk for severe OHSS.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was obtained for this study. There are no conflicts of interest.

Gonadotropin-releasing hormone agonist for ovulation trigger - OHSS prevention and use of modified luteal phase support for fresh embryo transfer

The introduction of gonadotrophin-releasing hormone agonist (GnRHa) trigger greatly impacted modern IVF treatment. Patients at low risk of ovarian hyperstimulation syndrome (OHSS) development, undergoing fresh embryo transfer and GnRHa trigger can be offered a virtually OHSS-free treatment with non-inferior reproductive outcomes by using a modified luteal phase support in terms of small boluses of human chorionic gonadotrophin (hCG), daily recombinant luteinizing hormone LH (rLH) or GnRHa. In the OHSS risk patient, GnRHa trigger can safely be performed, followed by a 'freeze-all' policy with a minimal risk of OHSS development and high live birth rates in the subsequent frozen embryo transfer cycle. Importantly, GnRHa trigger opened the 'black box' of the luteal phase, promoting research in the most optimal steroid levels during the luteal phase. GnRHa trigger allows high-dose gonadotropin stimulation to achieve the optimal number of oocytes and embryos needed to ensure the highest chance of live birth. This review thoroughly discusses how the GnRHa trigger concept adds safety and efficacy to modern IVF in terms of OHSS prevention. Furthermore, the optimal luteal phase management after GnRHa trigger in fresh embryo transfer cycles is discussed.

Gonadotropin-Releasing Hormone Agonist Versus Human Chorionic Gonadotropin for Ovulation Induction in Polycystic Ovary Syndrome Patients Undergoing Intrauterine Insemination: A Randomised Controlled Trial

Background: Gonadotropins have been recommended to improve ovulation, pregnancy and live birth rates in polycystic ovary syndrome (PCOS) patients with anovulatory infertility and clomiphene citrate (CC) resistance. However, this could increase the risk of ovarian hyperstimulation syndrome (OHSS). Gonadotropin-releasing hormone agonist (GnRHa) triggering could significantly reduce the risk of OHSS in patients undergoing in vitro fertilisation. However, data on the use of GnRHa in intrauterine insemination (IUI) is limited. This study compared the effectiveness of GnRHa and human chorionic gonadotropin (hCG) for ovulation induction in PCOS patients undergoing IUI.

Methods: This non-inferiority, single-centre, randomised controlled trial was conducted at IVFMD, My Duc Hospital, Ho Chi Minh City, Vietnam between April 2016 and May 2018. PCOS patients aged 18–37 years with CC resistance and [Formula: see text] 3 developing ([Formula: see text] 16 mm) follicles on trigger day after stimulation with gonadotropins were eligible. Those with uterine abnormalities or tubal damage or inseminated with frozen semen were excluded. Triptorelin 0.1 mg or hCG 5000 IU was used when there was [Formula: see text] 1 follicle of [Formula: see text] 17 mm. IUI was performed at 36 hours after triggering. Primary outcome was ongoing pregnancy. Secondary outcomes were clinical pregnancy, multiple pregnancy, miscarriage and OHSS.

Results: A total of 380 patients were randomised (190 per group). Treatment groups had similar characteristics at baseline. Ongoing pregnancy rate was 23.7% in the GnRHa group versus 25.3% in the hCG group (Relative risk 0.94; 95% confidence interval, 0.66–1.34; p [Formula: see text] 0.81). Secondary outcome parameters were also not significantly different between the two groups. There were two cases of mild OHSS in the hCG group and none in the GnRHa group.

Conclusion: 0.1 mg triptorelin was non-inferior to 5000 IU hCG IU in PCOS patients undergoing ovulation induction by hMG followed by IUI with respect to pregnancy outcomes.

Novel Concepts for Inducing Final Oocyte Maturation in In Vitro Fertilization Treatment

Infertility affects one in six of the population and increasingly couples require treatment with assisted reproductive techniques. In vitro fertilization (IVF) treatment is most commonly conducted using exogenous FSH to induce follicular growth and human chorionic gonadotropin (hCG) to induce final oocyte maturation. However, hCG may cause the potentially life-threatening iatrogenic complication "ovarian hyperstimulation syndrome" (OHSS), which can cause considerable morbidity and, rarely, even mortality in otherwise healthy women. The use of GnRH agonists (GnRHas) has been pioneered during the last two decades to provide a safer option to induce final oocyte maturation. More recently, the neuropeptide kisspeptin, a hypothalamic regulator of GnRH release, has been investigated as a novel inductor of oocyte maturation. The hormonal stimulus used to induce oocyte maturation has a major impact on the success (retrieval of oocytes and chance of implantation) and safety (risk of OHSS) of IVF treatment. This review aims to appraise experimental and clinical data of hormonal approaches used to induce final oocyte maturation by hCG, GnRHa, both GnRHa and hCG administered in combination, recombinant LH, or kisspeptin. We also examine evidence for the timing of administration of the inductor of final oocyte maturation in relationship to parameters of follicular growth and the subsequent interval to oocyte retrieval. In summary, we review data on the efficacy and safety of the major hormonal approaches used to induce final oocyte maturation in clinical practice, as well as some novel approaches that may offer fresh alternatives in future.

Comparison of two different dosage of GnRH agonist as ovulation trigger in oocyte donors: a randomized controled trial

OBJECTIVE

To compare the results obtained with two different GnRH agonist dosages: 0.3mg versus 0.4mg to trigger ovulation in oocyte donor cycles.

METHODS

Experimental controlled randomized trial including 40 patients from a private practice center. The patients were randomized into two groups. Group A received a single dose of Triptorelin 0.3mg (Decapeptyl®) 36hours before pick-up. Group B patients received Triptorelin 0.4mg (Decapeptyl®) before pick-up to final oocyte maturation. We evaluated the total number of oocytes collected, the number of mature oocytes and total days of ovarian stimulation.

RESULTS

The average of total collected oocytes were 16 (Group A) versus 15 (Group B), and the mean number of mature oocytes were 13 versus 12 respectively. The only variable showing a difference was the percentage of mature oocytes, which was greater in Group A, resulting in 84.6%, in contrast with those treated with 0.4mg of Triptorelin (78.6%), although these differences were not statistical significant (p=0.35). Days of stimulation did not differ between groups. No cases of empty follicle syndrome were reported.

CONCLUSIONS

We found that an increase from 0.3 to 0.4mg of triptorelin in an oocyte donation program might not improve outcomes. Nevertheless, more studies might be necessary, not only in oocyte donors but in sterile women as well, to evaluate how GnRH agonist dosage could affect the results among other factors.

Individual luteolysis pattern after GnRH-agonist trigger for final oocyte maturation

Final oocyte maturation using GnRH-agonist trigger in a GnRH-antagonist protocol is increasingly common, as ovarian hyperstimulation syndrome is almost completely avoided. However, this approach might lead to reduced pregnancy rates due to severe luteolysis. This proof of concept study evaluated the extend of luteolysis by measuring progesterone levels 48 hours after oocyte retrieval in 51 patients, who received GnRH-agonist trigger for final oocyte maturation in a GnRH-antagonist protocol due to the risk of ovarian hyperstimulation syndrome. It was shown, that luteolysis after GnRHa-trigger differs greatly among patients, with progesterone levels ranging from 13.0 ng/ml to ≥ 60.0 ng/ml, 48 hours after oocyte retrieval. Significant positive correlations could be demonstrated between progesterone levels and the number of ovarian stimulation and suppression days (p = 0.006 and p = 0.002 respectively), the total amount of medication used for ovarian suppression (p = 0.015), the level of progesterone on the day of final oocyte maturation (p = 0.008) and the number of retrieved oocytes (p = 0.019). Therefore it was concluded, that luteolysis after GnRH-agonist trigger is patient-specific and also luteal phase support requires individualization. Longer stimulation duration as well as a higher level of progesterone on the day of final oocyte maturation and more retrieved oocytes will result in higher levels of progesterone 48 hours after oocyte retrieval.

Ovarian hyperstimulation syndrome in the 21st century: the role of gonadotropin-releasing hormone agonist trigger and kisspeptin

PURPOSE OF REVIEW

Ovarian hyperstimulation syndrome (OHSS) complicates a considerable part of stimulated in-vitro fertilization (IVF) cycles and is a potential iatrogenic cause of death in otherwise healthy women undergoing fertility treatment. The triggering factor of OHSS is the widespread use of human chorionic gonadotropin (hCG) to induce final oocyte maturation. The aim of this review is to summarize different approaches available, using alternative triggering protocols such as gonadotropin-releasing hormone agonist (GnRHa) or kisspeptin for final oocyte maturation.

RECENT FINDINGS

According to the latest European Society of Human Reproduction and Embryology report, the incidence of OHSS ranges from 0.18 to 1.40% in European countries. However, OHSS is still subject to substantial underreporting. New triggering protocols using GnRHa have shown to be similar to the gold standard hCG-trigger with regard to the reproductive outcome, but with a significant decrease in - and almost elimination of - OHSS. Lately, promising results have been reported for the use of kisspeptin to induce final oocyte maturation. Although until now no study has been performed in an OHSS risk population, theoretically, the risk of OHSS development might be even further reduced after kisspeptin trigger.

SUMMARY

GnRHa trigger is currently the best tool we have to prevent OHSS and at the same time maintain good reproductive outcomes. Future research will explore the safety and efficacy of kisspeptin trigger.

Gonadotropin-releasing hormone agonist trigger in oocyte donors co-treated with a gonadotropin-releasing hormone antagonist: a dose-finding study

OBJECTIVE

To determine the optimal GnRH agonist dose for triggering of oocyte maturation in oocyte donors.

DESIGN

Single-center, randomized, parallel, investigator-blinded trial.

SETTING

IVFMD, My Duc Hospital, Ho Chi Minh City, Vietnam.

PATIENT(S)

One hundred sixty-five oocyte donors (aged 18-35 years, body mass index [BMI] <28 kg/m(2), antimüllerian hormone level >1.25 ng/mL, and antral follicle count ≥6).

INTERVENTION(S)

Ovulation trigger with 0.2, 0.3, or 0.4 mg triptorelin in a GnRH antagonist cycle.

MAIN OUTCOME MEASURE(S)

The primary end point was number of metaphase II oocytes. Secondary end points were fertilization and cleavage rates, number of embryos and top-quality embryos, steroid levels, ovarian volume, and ongoing pregnancy rate (PR) in recipients.

RESULT(S)

There were no significant differences between the triptorelin 0.2, 0.3, and 0.4 mg trigger groups with respect to number of metaphase II oocytes (16.0 ± 8.5, 15.9 ± 7.8, and 14.7 ± 8.4, respectively), embryos (13.2 ± 7.8, 11.7 ± 6.9, 11.8 ± 7.0), and number of top-quality embryos (3.8 ± 2.9, 3.6 ± 3.0, 4.1 ± 3.0). Luteinizing hormone levels at 24 hours and 36 hours after trigger was significantly higher with triptorelin 0.4 mg versus 0.2 mg and 0.3 mg (9.8 ± 7.1 IU/L vs. 7.3 ± 4.1 IU/L and 7.2 ± 3.7 IU/L, respectively; 4.6 ± 3.2 IU/L vs. 3.2 ± 2.3 IU/L and 3.3 ± 2.1 IU/L, respectively. Progesterone level at oocyte pick-up +6 days was significantly higher in the 0.4-mg group (2.2 ± 3.7 ng/ml) versus 0.2 mg (1.1 ± 1.0 ng/ml) and 0.3 mg (1.2 ± 1.6 ng/ml). One patient developed early-onset severe ovarian hyperstimulation syndrome (OHSS).

CONCLUSION(S)

No significant differences between triptorelin doses of 0.2, 0.3, and 0.4 mg used for ovulation trigger in oocyte donors were seen with regard to the number of mature oocytes and top-quality embryos.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02208986.

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.

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.

Assisted reproductive techniques

Assisted reproductive technologies (ART) encompass fertility treatments, which involve manipulations of both oocyte and sperm in vitro. This chapter provides a brief overview of ART, including indications for treatment, ovarian reserve testing, selection of controlled ovarian hyperstimulation (COH) protocols, laboratory techniques of ART including in vitro fertilization (IVF), and intracytoplasmic sperm injection (ICSI), embryo transfer techniques, and luteal phase support. This chapter also discusses potential complications of ART, namely ovarian hyperstimulation syndrome (OHSS) and multiple gestations, and the perinatal outcomes of ART.

GnRH agonist for triggering of final oocyte maturation: time for a change of practice?

BACKGROUND

GnRH agonist (GnRHa) triggering has been shown to significantly reduce the occurrence of ovarian hyperstimulation syndrome (OHSS) compared with hCG triggering; however, initially a poor reproductive outcome was reported after GnRHa triggering, due to an apparently uncorrectable luteal phase deficiency. Therefore, the challenge has been to rescue the luteal phase. Studies now report a luteal phase rescue, with a reproductive outcome comparable to that seen after hCG triggering.

METHODS

This narrative review is based on expert presentations and subsequent group discussions supplemented with publications from literature searches and the authors' knowledge. Moreover, randomized controlled trials (RCTs) were identified and analysed either in fresh IVF cycles with embryo transfer (ET), oocyte donation cycles or cycles without ET; risk differences were calculated regarding pregnancy rate and OHSS rate.

RESULTS

In fresh IVF cycles with ET (9 RCTs) no OHSS was reported after GnRHa triggering [0% incidence in the GnRHa group: risk difference 5% (with 95% CI: -0.07 to 0.02)]. Importantly, the delivery rate improved significantly after modified luteal support [6% risk difference in favour of the HCG group (95% CI: -0.14 to 0.2)] when compared with initial studies with conventional luteal support [18% risk difference (95% CI: -0.36 to 0.01)]. In oocyte donation cycles (4 RCTs) the OHSS incidence is 0% [10% risk difference (95% CI: 0.02-0.40)].

CONCLUSIONS

GnRHa triggering is a valid alternative to hCG triggering, resulting in an elimination of OHSS. After modified luteal support there is now a non-significant difference of 6% in delivery rate in favour of hCG triggering.

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

BACKGROUND

Gonadotropin-releasing hormone (GnRH) antagonist protocols for pituitary down regulation in in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) allow the use of GnRH agonists for triggering final oocyte maturation. Currently, human chorionic gonadotropin (HCG) is still the standard medication for this purpose. The effectiveness of triggering with a GnRH agonist compared to HCG measured as pregnancy and ovarian hyperstimulation(OHSS) rates are unknown.

OBJECTIVES

To compare the effectiveness of a GnRH agonist with HCG for triggering final oocyte maturation in IVF and ICSI patients undergoing controlled ovarian hyperstimulation in a GnRH antagonist protocol followed by embryo transfer. 

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE , EMBASE, the National Research Register, the Medical Research Council's Clinical Trials Register, and the NHS Centre for Reviews and Dissemination database. We also examined the reference lists of all known primary studies and review articles, citation lists of relevant publications and abstracts of major scientific meetings.

SELECTION CRITERIA

All randomised controlled studies (RCTs) reporting data comparing clinical outcomes for women undergoing IVF and ICSI cycles and using a GnRH agonist in comparison with HCG for final oocyte maturation triggering.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data.

MAIN RESULTS

We identified 11 RCTs (n = 1055). Eight studies assessed fresh autologous cycles and three studies assessed donor-recipient cycles. In fresh-autologous cycles, GnRH agonist was less effective than HCG in terms of the live birth rate per randomised woman (OR 0.44, 95% CI 0.29 to 0.68; 4 RCTs) and ongoing pregnancy rate per randomised woman (OR 0.45, 95% CI 0.31 to 0.65; 8 RCTs). For a group with a 30% live birth or ongoing pregnancy rate using HCG, the rate would be between 12% and 22% using an GnRH agonist. Moderate to severe ovarian hyperstimulation syndrome (OHSS) incidence per randomised woman was significantly lower in the GnRH agonist group compared to the HCG group (OR 0.10, 95% CI 0.01 to 0.82; 5 RCTs). For a group with a 3% OHSS rate using HCG the rate would be between 0% and 2.6% using GnRH agonist. In donor recipient cycles, there was no evidence of a statistical difference in the live birth rate per randomised woman (OR 0.92, 95% CI 0.53 to 1.61; 1 RCT).

AUTHORS' CONCLUSIONS

We do not recommend that GnRH agonists be routinely used as a final oocyte maturation trigger in fresh autologous cycles because of lowered live birth rates and ongoing pregnancy rates. An exception could be made for women with high risk of OHSS, after appropriate counselling.

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

BACKGROUND

Gonadotropin-releasing hormone (GnRH) antagonist protocols for pituitary down regulation in in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) allow the use of GnRH agonists for triggering final oocyte maturation. Currently, human chorionic gonadotropin (HCG) is still the standard medication for this purpose. The effectiveness of triggering with a GnRH agonist compared to HCG measured as pregnancy and ovarian hyperstimulation(OHSS) rates are unknown.

OBJECTIVES

To compare the effectiveness of a GnRH agonist with HCG for triggering final oocyte maturation in IVF and ICSI patients undergoing controlled ovarian hyperstimulation in a GnRH antagonist protocol followed by embryo transfer. 

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE , EMBASE, the National Research Register, the Medical Research Council's Clinical Trials Register, and the NHS Centre for Reviews and Dissemination database. We also examined the reference lists of all known primary studies and review articles, citation lists of relevant publications and abstracts of major scientific meetings.

SELECTION CRITERIA

All randomised controlled studies (RCTs) reporting data comparing clinical outcomes for women undergoing IVF and ICSI cycles and using a GnRH agonist in comparison with HCG for final oocyte maturation triggering.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data.

MAIN RESULTS

We identified 11 RCTs (n = 1055). Eight studies assessed fresh autologous cycles and three studies assessed donor-recipient cycles. In fresh-autologous cycles, GnRH agonist was less effective than HCG in terms of the live birth rate per randomised woman (OR 0.44, 95% CI 0.29 to 0.68; 4 RCTs) and ongoing pregnancy rate per randomised woman (OR 0.45, 95% CI 0.31 to 0.65; 8 RCTs). For a group with a 30% live birth or ongoing pregnancy rate using HCG, the rate would be between 12% and 22% using an GnRH agonist. Moderate to severe ovarian hyperstimulation syndrome (OHSS) incidence per randomised woman was significantly lower in the GnRH agonist group compared to the HCG group (OR 0.10, 95% CI 0.01 to 0.82; 5 RCTs). For a group with a 3% OHSS rate using HCG the rate would be between 0% and 2.6% using GnRH agonist. In donor recipient cycles, there was no evidence of a statistical difference in the live birth rate per randomised woman (OR 0.92, 95% CI 0.53 to 1.61; 1 RCT).

AUTHORS' CONCLUSIONS

We do not recommend that GnRH agonists be routinely used as a final oocyte maturation trigger in fresh autologous cycles because of lowered live birth rates and ongoing pregnancy rates. An exception could be made for women with high risk of OHSS, after appropriate counselling.

Early hCG addition to rFSH for ovarian stimulation in IVF provides better results and the cDNA copies of the hCG receptor may be an indicator of successful stimulation

A simple, safe and cost-effective treatment protocol in ovarian stimulation is of great importance in IVF practice, especially in the case of previous unsuccessful attempts. hCG has been used as a substitute of LH because of the degree of homology between the two hormones. The main aim of this prospective randomized study was to determine, for the first time, whether low dose hCG added to rFSH for ovarian stimulation could produce better results compared to the addition of rLH in women entering IVF-ET, especially in those women that had previous IVF failures. An additional aim was to find an indicator that would allow us to follow-up ovarian stimulation and, possibly, modify it in order to achieve a better IVF outcome; and that indicator may be the cDNA copies of the LH/hCG receptor. Group A patients (n = 58) were administered hCG and Group B rLH (n = 56) in addition to rFSH in the first days of ovarian stimulation. The number of follicles and oocytes and, most importantly, implantation and pregnancy rates were shown to be statistically significantly higher in the hCG group. This study has also determined, for the first time to our best knowledge, m-RNA for LH/hCG receptors in the lymphocytes of peripheral blood 40 h before ovum pick-up. cDNA levels of the hCG receptor after ovarian stimulation were significantly higher among women receiving hCG compared to those receiving LH. In addition, higher levels were encountered among women with pregnancy compared to those without, although this was not statistically significant due to the small number of pregnancies. It seems that hCG permits a highly effective and more stable occupancy of rLH/hCG receptors and gives more follicles and more oocytes. The determination of cDNA copies could be, in the future, a marker during ovulation induction protocols and of course a predictor for the outcome of ART in the special subgroup of patients with previous failures.

1,500 IU human chorionic gonadotropin administered at oocyte retrieval rescues the luteal phase when gonadotropin-releasing hormone agonist is used for ovulation induction: a prospective, randomized, controlled study

OBJECTIVE

To prospectively assess the reproductive outcome with a small bolus of hCG administered on the day of oocyte retrieval after ovulation induction with a GnRH agonist (GnRHa).

DESIGN

Prospective, randomized trial.

SETTING

Three hospital-based IVF clinics.

PATIENT(S)

Three hundred five IVF/intracytoplasmic sperm injection patients after a GnRH antagonist protocol.

INTERVENTION(S)

Ovulation induction was performed with either 10,000 IU hCG or 0.5 mg GnRHa (buserelin) supplemented with 1,500 IU hCG on the day of oocyte retrieval.

MAIN OUTCOME MEASURE(S)

Reproductive outcome in the two groups.

RESULT(S)

No significant differences were seen regarding positive hCG/ET rate (48% and 48%), ongoing pregnancy rate (26% and 33%), delivery rate (24% and 31%), and rate of early pregnancy loss (21% and 17%) between the GnRHa and 10,000 IU hCG groups, respectively.

CONCLUSION(S)

A small bolus of hCG in the GnRHa group secured the luteal phase, resulting in a comparable reproductive outcome in the two groups. However, a nonsignificant difference of 7% in delivery rates justifies further studies to refine the use of GnRHa for ovulation induction.

Rescue of corpus luteum function with peri-ovulatory HCG supplementation in IVF/ICSI GnRH antagonist cycles in which ovulation was triggered with a GnRH agonist: a pilot study

Previous studies found a poor clinical outcome when a GnRH agonist (GnRHa) was used to trigger ovulation in GnRH antagonist IVF/ICSI cycles. This study aimed to determine the clinical and endocrine effects as well the optimal timing of HCG supplementation. Forty-five normogonadotrophic IVF/ICSI patients following a flexible antagonist protocol were prospectively randomized (sealed envelopes) to triggering of ovulation with a single bolus of either 10,000 IU of HCG (group 1, n = 15) or 0.5 mg buserelin s.c. In addition, the GnRHa triggered group was randomized into two groups: group 2 (n = 17) was supplemented with HCG 1500 IU, 12 h after ovulation induction and group 3 (n = 13) was supplemented with HCG 1500 IU 35 h after ovulation induction. Group 1 and group 3 had significantly higher luteal phase concentrations of progesterone (P < 0.001) as compared with group 2. Moreover, the clinical pregnancy rate of groups 1 and 3 was similar and significantly higher (P < 0.02) than that of group 2. A larger study, however, is required to substantiate these differences. No differences were seen regarding mid-luteal inhibin A concentrations between the three groups. Triggering of ovulation with GnRHa supplemented with 1500 IU HCG 35 h later (group 3) seems to secure a normal luteal phase and a normal clinical pregnancy outcome.

Luteal phase support in assisted reproductive technology

PURPOSE OF REVIEW

The purpose of this review is to discuss luteal support in assisted reproduction and to provide an evidence-based overview of the current options available.

RECENT FINDINGS

The luteal phase has been found to be defective in virtually all of the stimulation protocols used for in-vitro fertilization. Common mechanisms such as supraphysiological levels of estradiol, decreased output of luteinizing hormone, inhibition of the corpus luteum and asynchronization of estradiol and progesterone may be involved in insufficient function of the corpus luteum in assisted reproductive technology.

SUMMARY

Gonadotropin releasing hormone agonist undoubtedly provides benefits in stimulated cycles, however it also has adverse effects, inhibition of the corpus luteum together with supraphysiological hormonal profiles finally leading to luteal phase defects. Luteal phase support with human chorionic gonadotropin or progesterone after assisted reproduction results in increased pregnancy rates. The role of luteal phase support in these cycles has also been recently elucidated. Use of human chorionic gonadotropin for luteal phase support is associated with a marked increase in the risk of ovarian hyperstimulation syndrome, therefore progesterone is the preferred choice. Data on the benefits of estrogen supplementation are conflicting. Among the routes of progesterone administration, reductions in pregnancy rates are noted on oral administration. In spite of a lack of statistical significance, the intramuscular route seems to be more beneficial than the vaginal route when considering rates of ongoing pregnancy and live birth. Further clarification is needed on the ideal dose, the optimal route and the duration of progesterone administration in assisted reproduction.

GnRH agonist (buserelin) or hCG for ovulation induction in GnRH antagonist IVF/ICSI cycles: a prospective randomized study

BACKGROUND

We aimed to determine the efficacy of ovarian hyperstimulation protocols employing a GnRH antagonist to prevent a premature LH rise allowing final oocyte maturation and ovulation to be induced by a single bolus of either a GnRH agonist or hCG.

METHODS

A total of 122 normogonadotrophic patients following a flexible antagonist protocol was stimulated with recombinant human FSH and prospectively randomized (sealed envelopes) to ovulation induction with a single bolus of either 0.5 mg buserelin s.c. (n = 55) or 10,000 IU of hCG (n = 67). A maximum of two embryos was transferred. Luteal support consisted of micronized progesterone vaginally, 90 mg a day, and estradiol, 4 mg a day per os.

RESULTS

Ovulation was induced with GnRH agonist in 55 patients and hCG in 67 patients. Significantly more metaphase II (MII) oocytes were retrieved in the GnRH agonist group (P < 0.02). Significantly higher levels of LH and FSH (P < 0.001) and significantly lower levels of progesterone and estradiol (P < 0.001) were seen in the GnRH agonist group during the luteal phase. The implantation rate, 33/97 versus 3/89 (P < 0.001), clinical pregnancy rate, 36 versus 6% (P = 0.002), and rate of early pregnancy loss, 4% versus 79% (P = 0.005), were significantly in favour of hCG.

CONCLUSIONS

Ovulation induction with a GnRH agonist resulted in significantly more MII oocytes. However, a significantly lower implantation rate and clinical pregnancy rate in addition to a significantly higher rate of early pregnancy loss was seen in the GnRH agonist group, most probably due to a luteal phase deficiency.

Time to revolutionize the triggering of ovulation

Methods used for ovarian stimulation constantly change with advances in gonadotrophin therapy. In this Commentary, an appeal is made for more attention to the use of LH for the induction of ovulation. Its typical characteristics during the LH surge are finely balanced to induce normal ovulation and luteinization. It does not induce ovarian hyperstimulation, for example. The recent commercial availability of recombinant LH (LHr) offers a chance of escaping from the use of urinary human chorionic gonadotrophin (HCG) and its varied forms such as those with a shorter half-life. It should also avoid the weakly effective bursts of FSH and LH and weak luteal phases released associated with the use of gonadotrophin-releasing hormone agonists. Currently, large dosages of LHr are needed to match the endocrine events typical of inducing ovulation by the endogenous LH surge. In the interests of patients' safety and improved forms of luteal phase endocrinology, research should be devoted to improving the properties of rLH to make it induce surges similar to endogenous discharges. This would replace the current use of HCG to induce ovulation, with its attendant risks of ovarian hyperstimulation and luteal phase anomalies.