Timing of human chorionic gonadotrophin (hCG) hormone administration in IVF protocols using GnRH antagonists: a randomized controlled trial

Do women with severely diminished ovarian reserve undergoing modified natural-cycle in-vitro fertilization benefit from earlier trigger at smaller follicle size?

OBJECTIVE

To evaluate whether trigger and oocyte collection at a smaller follicle size decreases the risk of premature ovulation while maintaining the reproductive potential of oocytes in women with a severely diminished ovarian reserve undergoing modified natural-cycle in-vitro fertilization.

METHODS

This was a retrospective cohort study including women who had at least one unsuccessful cycle (due to no response) of conventional ovarian stimulation with a high dosage of gonadotropins and subsequently underwent a modified natural cycle with a solitary growing follicle (i.e. only one follicle > 10 mm at the time of trigger). The association between follicle size at trigger and various cycle outcomes was tested using regression analyses.

RESULTS

A total of 160 ovarian stimulation cycles from 110 patients were included in the analysis. Oocyte pick-up (OPU) was performed in 153 cycles and 7 cycles were canceled due to premature ovulation. Patients who received their trigger at smaller follicle sizes (≤ 15 mm) had significantly lower rates of premature ovulation and thus higher rates of OPU (98.9% vs 90.8%; odds ratio, 9.56 (95% CI, 1.58-182.9); P = 0.039) compared with those who received their trigger at larger follicle sizes (> 15 mm). On multivariable analysis, smaller follicle sizes at trigger (> 10 to 13 mm, > 13 to 15 mm, > 15 mm to 17 mm) were not associated significantly with a lower rate of cumulus-oocyte complex (COC) retrieval, metaphase-II (MII) oocytes or blastulation when compared to the > 17-mm group. On sensitivity analysis including only the first cycle of each couple, the maturity rate among those with COC retrieval was highest in follicle sizes > 15 to 17 mm (92.3%) and > 13 to 15 mm (91.7%), followed by > 10 to 13 mm (85.7%) and lowest in the > 17-mm group (58.8%). During the study period, five euploid blastocysts developed from 48 fertilized MII oocytes with follicle sizes of 12 mm (n = 3), 14 mm (n = 1) and 16 mm (n = 1) at trigger. Of those, four were transferred and resulted in two live births, both of which developed from follicles with a size at trigger of 12 mm.

CONCLUSIONS

The ideal follicle size for triggering oocyte maturation may be smaller in women with a severely diminished ovarian reserve managed on a modified natural cycle when compared to conventional cut-offs. The risk of OPU cancellation was significantly higher in women triggered at follicle size > 15 mm and the yield of mature oocytes was not adversely affected in women triggered at follicle size > 13 to 15 mm compared with > 15 to 17 mm. Waiting for follicles to reach sizes > 17mm may be detrimental to achieving optimal outcome. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Meta-analysis of trigger timing in normal responders undergoing GnRH antagonist ovarian hyperstimulation protocol

IMPORTANCE

The first meta-analysis focused only on gonadotropin-releasing hormone (GnRH) antagonists, which helped determine the effect of delay trigger on pregnancy outcomes.

OBJECTIVE

To evaluate the impact of delay trigger compared with standard trigger in normal responders undergoing GnRH antagonist protocol in improving pregnancy outcomes.

METHODS

Studies published before April 2023 in PubMed, EMBASE, Cochrane Library, Web of Science, CNKI, Wanfang, VIP and CBM databases were searched. Randomized controlled trials (RCTs) and cohort studies conducted in normal responders reporting the efficacy of delay trigger using GnRH antagonist protocol were included. Data were combined to calculate mean differences (MD) for continuous variables and odd ratios (OR) for categorical variables with their corresponding 95% confidence intervals (CIs). Heterogeneity was assessed using Cochran's Q test.

RESULTS

Endpoints, including clinical pregnancy rate (CPR), live birth rate (LBR), the number of oocyte retrievals and embryos, and fertilization rate, were analyzed. Six (6) clinical studies (4 RCTs and 2 cohort studies) with 1,360 subjects were included. The pooled results showed that the number of oocyte retrievals (MD: 1.20, 95% CI: 1.10, 1.30, p < 0.01), fertilization rate (MD: 0.64, 95% CI: 0.29, 0.99, p < 0.01) and days of stimulation (MD: 0.95; 95% CI: 0.54, 1.37; p < 0.01) in the delay trigger group was significantly higher than that in the standard trigger group. However, there was no significant difference in the number of embryos (MD: 0.19, 95% CI: -0.29, 0.67, p = 0.44), CPR (OR: 1.12; 95% CI: 0.72, 1.75; p = 0.062), and LBR (OR: 1.23; 95% CI: 0.90, 1.66; p = 0.19) between the two trigger groups.

CONCLUSION

Delaying trigger time in GnRH antagonist protocol increased the number of oocytes retrieved but not the number of embryos. Furthermore, delay trigger shot was not associated with a clinical benefit towards CPR and LBR in women who underwent fresh embryo transfer cycles.

TRIAL REGISTRATION

The International Prospective Register of Systematic Reviews (PROSPERO), registration number: CRD42023413217.

Increasing dominant follicular proportion negatively associated with good clinical outcomes in normal ovarian responders using the depot GnRH agonist protocol: a large-sample retrospective analysis

BACKGROUND

Currently, there is no universal criteria for the trigger time of controlled ovarian hyperstimulation (COH), especially with the emerging depot GnRH agonist protocol. It is challenging to explore an indicator that is representative of target follicle cohort development as an alternative to the conventional approach of determining the trigger time based on a few leading follicles.

METHODS

This was a large-sample retrospective analysis. Between January 2016 and January 2020, 1,925 young normal ovarian responders who underwent their first in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) cycle using the depot GnRH agonist protocol were included. They were divided into three groups based on the dominant follicular proportion (DFP, defined as the ratio of ≥ 18 mm dominant follicles/ ≥ 14 mm large follicles on the human chorionic gonadotropin (HCG) day; Group A: < 30%; Group B: 30%-60%; and Group C: ≥ 60%). The binary logistic regression and multivariate linear regression were used to assess whether the DFP was associated with clinical pregnancy, the number of frozen blastocysts, the blastocyst formation rate, and the low number of frozen blastocysts.

RESULTS

The logistic regression analysis showed that compared with Group A, the odds ratio (OR) for clinical pregnancy was 1.345 in Group B (P = 0.023), and there was no statistical difference between Group C and Group A (P = 0.216). The multivariate linear regression analysis showed that DFP was negatively associated with the number of frozen blastocysts (β ± SE: Group B vs. Group A = - 0.319 ± 0.115, P = 0.006; Group C vs. Group A = - 0.432 ± 0.154, P = 0.005) as well as the blastocyst formation rate (β ± SE: Group B vs. Group A = - 0.035 ± 0.016, P = 0.031; Group C vs. Group A = - 0.039 ± 0.021, P = 0.067). Furthermore, the OR for the low number of frozen blastocysts was 1.312 in Group B (P = 0.039) and 1.417 in Group C (P = 0.041) compared to Group A.

CONCLUSIONS

For young normal ovarian responders using the depot GnRH agonist protocol, increasing DFP might reduce the developmental potential of oocytes and reduce the number of available blastocysts, and this might result in a lower cumulative pregnancy rate. However, further confirmation using strict prospective randomised controlled studies is required.

A machine learning algorithm can optimize the day of trigger to improve in vitro fertilization outcomes

OBJECTIVE

To determine whether a machine learning causal inference model can optimize trigger injection timing to maximize the yield of fertilized oocytes (2PNs) and total usable blastocysts for a given cohort of stimulated follicles.

DESIGN

Descriptive and comparative study of new technology.

SETTING

Tertiary academic medical center.

PATIENT(S)

Patients undergoing IVF with intracytoplasmic sperm injection from 2008 to 2019 (n = 7,866).

INTERVENTION(S)

Causal inference was performed with the use of a T-learner. Bagged decision trees were used to perform inference. The decision was framed as either triggering on that day or waiting another day. All patient characteristics and stimulation parameters on a given day were used to determine the recommendation.

MAIN OUTCOME MEASURE(S)

Average outcome improvement in total 2PNs and usable blastocysts compared with the physician's decision.

RESULT(S)

For evaluation of average outcome improvement on 2PNs, the benefit of following the model's recommendation was 3.015 (95% CI 2.626, 3.371) more 2PNs. For total usable blastocysts, the benefit was 1.515 (95% CI 1.134, 1.871) more usable blastocysts. Given that the physicians-model agreement was 52.57% and 61.89%, respectively, algorithm-assisted trigger decisions yield, on average, 1.430 more 2PNs and 0.577 more total usable blastocysts per stimulation. The most important features weighted in the model's decision were the number of follicles 16-20 mm in diameter, the number of follicles 11-15 mm in diameter, and estradiol level, in that order.

CONCLUSION(S)

The use of this machine learning algorithm to optimize trigger injection timing may lead to a significant increase in the number of 2PNs and total usable blastocysts obtained from an IVF stimulation cycle when compared with physician decisions. Future research is required to confirm these findings prospectively.

Ovarian stimulation for freeze-all IVF cycles: a systematic review

BACKGROUND

Freeze-all IVF cycles are becoming increasingly prevalent for a variety of clinical indications. However, the actual treatment objectives and preferred treatment regimens for freeze-all cycles have not been clearly established.

OBJECTIVE AND RATIONALE

We aimed to conduct a systematic review of all aspects of ovarian stimulation for freeze-all cycles.

SEARCH METHODS

A comprehensive search in Medline, Embase and The Cochrane Library was performed. The search strategy included keywords related to freeze-all, cycle segmentation, cumulative live birth rate, preimplantation genetic diagnosis, preimplantation genetic testing for aneuploidy, fertility preservation, oocyte donation and frozen-thawed embryo transfer. We included relevant studies published in English from 2000 to 2018.

OUTCOMES

Our search generated 3292 records. Overall, 69 articles were included in the final review. Good-quality evidence indicates that in freeze-all cycles the cumulative live birth rate increases as the number of oocytes retrieved increases. Although the risk of severe ovarian hyperstimulation syndrome (OHSS) is virtually eliminated in freeze-all cycles, there are certain risks associated with retrieval of large oocyte cohorts. Therefore, ovarian stimulation should be planned to yield between 15 and 20 oocytes. The early follicular phase is currently the preferred starting point for ovarian stimulation, although luteal phase stimulation can be used if necessary. The improved safety associated with the GnRH antagonist regimen makes it the regimen of choice for ovarian stimulation in freeze-all cycles. Ovulation triggering with a GnRH agonist almost completely eliminates the risk of OHSS without affecting oocyte and embryo quality and is therefore the trigger of choice. The addition of low-dose hCG in a dual trigger has been suggested to improve oocyte and embryo quality, but further research in freeze-all cycles is required. Moderate-quality evidence indicates that in freeze-all cycles, a moderate delay of 2–3 days in ovulation triggering may result in the retrieval of an increased number of mature oocytes without impairing the pregnancy rate. There are no high-quality studies evaluating the effects of sustained supraphysiological estradiol (E2) levels on the safety and efficacy of freeze-all cycles. However, no significant adverse effects have been described. There is conflicting evidence regarding the effect of late follicular progesterone elevation in freeze-all cycles.

WIDER IMPLICATIONS

Ovarian stimulation for freeze-all cycles is different in many aspects from conventional stimulation for fresh IVF cycles. Optimisation of ovarian stimulation for freeze-all cycles should result in enhanced treatment safety along with improved cumulative live birth rates and should become the focus of future studies.

Weekend-free scheduled IVF/ICSI procedures and single embryo transfer do not reduce live-birth rates in a general infertile population

INTRODUCTION

Scheduling of ovum pickup only on weekdays may result in cases of apparently suboptimal timing for human chorionic gonadotropin and ovum pickup. This study aimed to assess whether live-birth rates were reduced in women with a potentially suboptimal day for human chorionic gonadotropin and ovum pickup to avoid weekend work, according to ultrasonographic data on the day of human chorionic gonadotropin planning.

MATERIAL AND METHODS

An evaluation of the optimal human chorionic gonadotropin priming date was performed in treatment protocols of 1000 consecutive patients undergoing their first in vitro fertilization/intracytoplasmatic sperm injection with single-embryo transfer. An ideal ovum pickup day was characterized by human chorionic gonadotropin-scheduling when three or more follicles reached 17 mm (day 0) or with one day of delay (day +1) (n = 760). A non-ideal ovum pickup was either early (day -1, -2, -3) (n = 24) or delayed (day +2, +3, +4) (n = 216). Live-birth rates in the ideal and non-ideal ovum pickup groups was set as primary outcome measure.

RESULTS

Early-ovum pickups were excluded as they were infrequent. No differences between ideal and delayed ovum pickup groups were found regarding number of oocytes retrieved (9.87 vs. 9.78, p = 0.990), pregnancy rates (28.3% vs. 29.6%, p = 0.701) or live-birth rates (26.2% vs. 25.9%, p = 0.939). However, sub analyses indicated that treatment with gonadotropin releasing hormone antagonists resulted in significantly lower clinical pregnancy rates in delayed ovum pickups (odds ratio 0.46, p = 0.014), compared with agonist treatments.

CONCLUSIONS

Weekend work may not be needed for in vitro fertilization/intracytoplasmatic sperm injection single-embryo transfer treatments. However, in gonadotropin releasing hormone antagonist cycles, delaying ovum pickup more than one day may result in unfavorable outcomes.

The value of delaying hCG administration to enable maturation of medium-sized follicles in patients undergoing superovulation for IVF/ICSI

PURPOSE

The purpose of the study is to determine whether continued stimulation of mature follicles to allow "catch up" growth of medium-sized follicles in assisted reproductive technology compromises the clinical pregnancy (CPR) and live birth (LBR) rates in IVF/ICSI cycles.

METHODS

This retrospective cohort study reviewed 200 first IVF ± ICSI cycles out of a total of 340 cycles with complete data. Women underwent stimulation protocols with gonadotropins (Gn) and GnRH antagonist. Treatment cycles were divided into two groups (Gp): hCG administration delayed despite the presence of two mature follicles, defined as ≥ 18 mm [Gp1, n = 79] and hCG administration given when there were two mature follicles [Gp2, n = 121].

RESULTS

The patients in Gp1 were significantly younger than those in Gp2 [32.9 (4.5) vs. 34.3 (4.8), p = 0.04] and needed a median of one more day of superovulation before ovulation was triggered with hCG. The extra days was associated with the use of 450 [75-2025] more Gn, such that at the time the hCG was administered, patient's in group 1 had developed significantly greater number of follicles ≥ 18 mm [mean (SD), 4.9 (1.8) vs. 3.4 (1.7), p < 0.0001]. The clinical pregnancy (48.1 vs. 38.0%, [OR (95% CI)] [1.6 (1.0-2.5), p = 0.09]) and live birth (43.0 vs. 35.5%, [1.4 (0.9-2.3), p = 0.21]) rates per cycle started were not significantly different between the two groups. Forward stepwise logistic regression showed that only maternal age (p = 0.04) influenced clinical pregnancy rates (OR = 0.88, CI 0.78-0.99) and only the number of days for superovulation influenced live birth rates (OR = 0.65, CI 0.486-0.869).

CONCLUSION

This study demonstrated that delaying hCG administration to allow further growth of the medium-sized follicles added further days of superovulation and cost without improvement in CPR and LBR.

New Perspectives on Criteria for the Determination of HCG Trigger Timing in GnRH Antagonist Cycles

The aim of this study was to investigate 2 quantification criteria to evaluate the developmental condition of follicles cohort and clarify their impacts upon the determining of human chorionic gonadotropin trigger timing and the reproductive outcome: the proportion of mature follicles in growing follicles cohort on the day of human chorionic gonadotropin trigger and the peak estradiol level per oocyte on the day of human chorionic gonadotropin administration.Of the patients who underwent in vitro fertilization/ intracytoplasmic sperm injection-embryo transfer from 2011 to 2013, 492 controlled ovarian hyperstimulation cycles using gonadotropin-releasing hormone antagonists reaching the ovum pick-up and fresh embryo-transfer stage were included. Patients were divided into 3 groups according to their ≥17 mm/≥10 mm follicles ratio on the day of human chorionic gonadotropin administration (Low proportion: ≤30%, Middle proportion: 30%-60%, High proportion: ≥60%). Patients were divided into 5 groups according to their peak estradiol level/oocyte (Group A: <100 pg/mL per oocyte, Group B: 100-199 pg/mL per oocyte, Group C: 200-299 pg/mL per oocyte, Group D: 300-399 pg/mL per oocyte, Group E ≥400 pg/mL per oocyte) as well. Comparison among groups was made regarding ovarian stimulation characteristics, fertilization rate, good quality embryo rate, implantation, pregnancy, and live birth rates.On the basis of ≥17 mm/≥10 mm follicles ratio, the number of oocyte retrieved in low proportion group is more than other 2 groups. Implantation rate, clinical pregnancy, and live birth rate in high proportion group were 25.8%, 42.7%, and 31.1%, respectively, which is highest in 3 groups, and statistical significance existed between high and middle proportion groups. When the division is based on peak estradiol level/oocyte, the number of oocyte retrieved of ≥400 pg/mL per oocyte Group was significantly lowest compared with the other 4 groups. Matured ovum rate, fertilization rate, and good quality embryos rate exhibited an increasing trend as the peak estradiol level/oocyte increased. While pregnancy rate, implantation rate, and live birth rate were found to be lower whenever estradiol/oocyte ratio exceeded 400 pg/mL per oocyte or less than 100 pg/mL per oocyte, and there is statistical difference.Patients with the proportion of mature follicle reaching 60% on the day of human chorionic gonadotropin trigger and peak estradiol/oocyte level within 100∼399 pg/mL range can get a better pregnancy and implantation rate.

What are the best predictors for successful GnRH antagonist protocol in in vitro fertilization (IVF) treatment?

OBJECTIVE

To determine factors that affect the success rate of GnRH antagonist protocol in in vitro fertilization (IVF) treatment.

DESIGN

Retrospective cohort study.

PATIENTS

Patients who underwent IVF cycle with their first GnRH antagonist protocol.

INTERVENTION

Antagonist protocol during IVF treatment. The main outcome measurements were; Number of retrieved oocytes, embryo quality and pregnancy rate.

RESULTS

Gravidity was negatively correlated with number of eggs (p = 0.017), while total follicle number ≥15 (p = 0.044) and E(2) on day of human chorionic gonadotropin (HCG) (p = 0.000) had a positive correlation with number of eggs. Maximum follicle size at HCG administration showed a trend toward an inverse correlation (p = 0.053). Addition of LH to drug stimulation was negatively correlated with number of eggs in comparison to rFSH only (p = 0.013 and 0.0000, respectively). Age and number of frozen eggs were negatively correlated with successful pregnancy (p = 0.025 and 0.004, respectively), while embryo quality, gravidity and number of embryos were positive (p = 0.011 and 0.014, respectively).

CONCLUSION

Controlled parameters like timing of antagonist start, duration of antagonist and the optimal leading follicle diameter for HCG triggering had no effect on treatment outcomes.

Advancing or postponing the day of human chorionic gonadotropin does not matter for the outcome in assisted reproductive technology

CONTEXT:

The primary outcome is to remove the worry of getting immature oocytes with early administration of human chorionic gonadotropin (hCG).

AIM:

The aim was to find out the association between the day of hCG administration and follicular response in relation to the number and maturity of oocytes, and fertilization rate in assisted reproduction to avoid weekend oocyte recovery (OR).

SETTINGS AND DESIGN:

Retrospective study was carried out in the university infertility clinic.

MATERIALS AND METHOD:

Controlled ovarian hyperstimulation (COH) in 94 patients undergoing assisted reproductive technology (2010-2011) with recombinant follicle stimulating hormone and timely gonadotropin-releasing hormone antagonist were analyzed regarding day of hCG from day 8-11. Oocyte maturity and fertilization was analyzed and correlated with the day of hCG administration.

STATISTICAL ANALYSIS:

Kruskal–Wallis test.

RESULTS:

The average number of >18 mm follicles observed from day 8-11 of hCG administration was not statistically different. However, the OR rate (54.2%), number of mature oocytes (92.5%), and fertilization rate (78.5%) was maximum in the patients where hCG was administered on day 8 of COH.

CONCLUSIONS:

The day of hCG administration between 8 and 11 does not affect the OR rate significantly although the number of oocytes recovered on day 8 are marginally higher compared with day 9-11. Hence, it is possible to safely avoid weekend oocyte retrieval, by delaying or advancing hCG administration without compromising the outcome.

Timing of human chorionic gonadotropin (hCG) hormone administration in IVF/ICSI protocols using GnRH agonist or antagonists: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effect of altering the timing of human chorionic gonadotropin (hCG) administration on the clinical outcome of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) using gonadotropic hormone releasing hormone (GnRH) agonist or antagonist.

METHODS

We systematically searched six databases. Randomized controlled trials (RCTs) of the effects of altering the timing of hCG administration on the clinical outcome of IVF and ICSI using GnRH agonist or antagonist were included. A meta-analysis was conducted following a quality evaluation performed with Cochrane Collaboration's Review Manager (RevMan) 5.0.2.

RESULTS

Seven RCTs and a total of 1295 participants were included. Significant difference was observed regarding estradiol and progesterone levels on the day of hCG administration and oocyte retrieval between early hCG and late hCG administration group and in favor of the latter. The fertilization rate was not statistically different between early and 24-h late hCG groups, but it is significantly higher in the 48-h late hCG group. The pooled results showed no significant differences in the ongoing pregnancy rate per oocyte pick-up, the miscarriage rate and the live birth rate.

CONCLUSION

The prolongation of follicular phase by delaying hCG administration could increase estradiol, progesterone levels and oocyte retrieval, which will not influence ongoing pregnancy rate per oocyte pick-up, miscarriage rate and live birth rate. Postponing hCG may enable increased flexibility of cycle scheduling to avoid weekend procedures.