hCG Trigger Research Articles

Dual trigger versus human chorionic gonadotropin trigger for blastocyst quality and cumulative live birth.

To evaluate the difference in the number of euploid blastocysts and cumulative live birth rate (LBR) between dual and human chorionic gonadotropin (hCG) triggers in poor and normal ovarian responders undergoing preimplantation genetic testing (PGT) cycles. This retrospective cohort study was enrolled from July 2018 to December 2021 and followed up until June 2024 at a single reproductive medical center. Overall, 1040 in vitro fertilization (IVF)-PGT and 784 frozen-thawed embryo transfer (FET) cycles were assessed. Dual (triptorelin acetate 0.2 mg and recombinant hCG [rhCG] 250 µg) or hCG (rhCG 250 µg) trigger was used for oocyte maturation in the gonadotropin-releasing hormone antagonist protocol and PGT cycles. We assessed the embryo outcomes and FET cumulative pregnancy outcomes. The number of oocytes retrieved (10.17 ± 5.22 vs 10.27 ± 5.14, P = 0.789), MII oocytes (8.24 ± 4.26 vs 8.28 ± 4.05, P = 0.888), blastocysts (2.16 ± 1.50 vs 2.12 ± 1.49, P = 0.729), euploid blastocysts (1.06 ± 1.14 vs 1.09 ± 1.23, P = 0.726), and the rate of cumulative LBR (24.9% vs 24.9%, P = 1.000) in the dual trigger group were comparable with those in the hCG group. The trigger method was not correlated with higher LBR based on logistic regression analysis (odds ratio[OR] = 1.040 [0.778-1.392], P = 0.790). For poor and normal ovarian responders, the dual trigger, compared with the hCG trigger, did not improve the PGT embryo outcomes and FET cumulative pregnancy outcomes.

Triggering oocyte maturation in IVF treatment in normal responders: a systematic review and network meta-analysis.

To compare efficacy and safety of hCG, GnRH agonist, dual, and double triggers in predicted normal responders undergoing ovarian stimulation and IVF DESIGN: A systematic review and network meta-analysis of randomized controlled trials (RCTs). RCTs indexed in PubMed, MEDLINE, EMBASE, clinical trial registries and Cochrane Database of Systematic Reviews up to December 2023. Twelve high-integrity RCTs comprising 1,931 women were included, which compared hCG trigger to GnRH agonist trigger, dual trigger, and double trigger. Statistical analysis was performed using STATA version 16. Key outcomes included clinical pregnancy rates (CPR), live birth rates (LBR), number of oocytes, number of mature oocytes, miscarriage rate and rates of ovarian hyperstimulation syndrome (OHSS). The network meta-analysis for CPR were relative risk (RR) 1.13 (95% Confidence Interval (CI):0.80-1.60) for hCG versus GnRH agonist trigger, RR 1.23 (95% CI:0.92-1.65) for hCG versus dual trigger, RR 0.38 (95% CI:0.21-0.69) for hCG versus double trigger, RR 1.09 (95% CI:0.70-1.70) for GnRH agonist versus dual trigger and 0.34 (95% CI:0.17-0.67) for GnRH agonist versus double trigger and RR 0.31 (95%CI:0.16-0.60) for double versus dual trigger. Dual trigger demonstrated the highest SUCRA (85.1%), indicating superior efficacy for clinical pregnancy rates. For LBR, while connectivity was limited, the RR was 1.31 (95% CI: 1.00-1.70) for dual versus hCG trigger, and RR 1.60 (95% CI: 1.05-2.43) for dual versus GnRH agonist trigger. OHSS rates were significantly lower with the GnRH agonist compared to hCG trigger (RR 0.56, 95% CI: 0.19-1.75). There were no randomized controlled trials reporting OHSS rates with the use of dual or double trigger. No significant differences were observed in the number of oocytes retrieved, mature oocytes, or miscarriage rates among the trigger protocols. The findings indicate that there is no evidence to suggest that using GnRH agonist, dual, or double protocols is superior to hCG trigger in improving clinical pregnancy rates. While live birth rates may benefit from dual trigger, results are limited by available RCTs. Larger, multicentre trials are needed for further evaluation of live birth rates and understanding of long-term outcomes.

Impact of progesterone concentration on hCG trigger day on clinical outcomes with cleavage-stage embryo transfer in in vitro fertilization cycles with an antagonist protocol

Objective: To investigate the impact of the progesterone concentration on human chorionic gonadotropin (hCG) trigger day in fresh cycles versus thawed transfer cycles (the freeze-all strategy) with an antagonist protocol, and to compare the differences in clinical outcomes. Methods: This retrospective cohort study included a total of 2 165 cycles conducted at Henan Provincial People's Hospital with cleavage-stage embryo (at least one top-quality) transfer between January 2017 and December 2023, with serum progesterone levels on hCG trigger day all≤6.34 nmol/L (i.e. 2 ng/ml). Multivariate logsitic regression analysis and curve fitting were performed based on different serum progesterone levels on hCG trigger day [≤3.17 nmol/L (i.e. 1 ng/ml) or 1-2 ng/ml]. Results: Multivariate regression analysis, by using cycle type (either fresh or frozen-thawed cycle) as the exposure variable, showed that the clinical pregnancy rate (≤1 ng/ml: OR=0.93, 95%CI: 0.75-1.14; 1-2 ng/ml: OR=1.05, 95%CI: 0.58-1.87) and live birth rate (≤1 ng/ml: OR=0.90, 95%CI: 0.71-1.13; 1-2 ng/ml: OR=1.53, 95%CI: 0.79-3.00) had no statistically significant differences in group of progesterone concentration ≤1 ng/ml or in group of 1-2 ng/ml. Using serum progesterone levels on hCG trigger day as a continuous variable for curve fitting analysis, the clinical pregnancy rate in fresh or thawed cycles showed no significant changes with increasing progesterone levels. Conclusions: In the antagonist protocol with cleavage-stage embryo transfer (at least one top-quality), when the serum progesterone level on hCG day is ≤2 ng/ml, there are no significant differences in clinical outcomes between thawed cycles and fresh cycles, including clinical pregnancy rate and live birth rate. Transferred in fresh cycles or choosing the freeze-all strategy could be selected based on the actual situation of the patients.

Does hCG-trigger in the mild stimulation protocol for endometrial preparation have any effect on pregnancy outcome in frozen-thawed embryo transfer?

BackgroundRecent literature has explored the role of human chorionic gonadotropin (hCG) triggering in frozen embryo transfer (FET) cycles with natural endometrial preparation. Despite this, the impact of hCG triggering on pregnancy outcomes following endometrial preparation with mild stimulation (mST) using Letrozole and Gonadotropins remains inadequately characterized. This study aimed to elucidate the effects of hCG-trigger on pregnancy outcomes in mST-FET cycles.MethodsIn the present retrospective cohort study, the pregnancy outcomes of 409 eligible patients who underwent FET cycles with endometrial preparation using a mild ovarian stimulation protocol by letrozole plus low dose gonadotropins at the Royan Institute between 2020 and 2022, were investigated. The study population were segregated into two distinct groups according to type of ovulation: the spontaneous ovulation group (n = 138) and the hCG-trigger group (n = 271). The pregnancy outcomes including implantation and clinical pregnancy rates (CPR) and live birth rates (LBR) were compared between two groups. The multivariable logistic regression was performed to detect the most significant variables related to the LBR in the mST-FET cycles.ResultsDemographic and baseline characteristics were comparable between groups. No significant difference was found in terms of implantation rate (0.65 ± 0.32 vs. 0.60 ± 0.30, P-value: 0.31), CPR (37% vs. 39.7%, P-value: 0.53), and LBR (35.5% vs. 37.3%, P-value: 0.74) in the spontaneous ovulation and hCG-trigger groups, respectively. The logistic regression analysis revealed that only the stage of the transferred embryo exhibited a significant relationship with LBR (blastocyst vs. cleavage: odds ratio (OR); 2.33, 95% confidence interval (CI):1.41–3.86, P-value = 0.001).ConclusionPregnancy outcomes in the mST-FET cycles, including implantation rate, CPR, and LBR are comparable in cycles with or without hCG triggering. Based on the findings from multivariate regression analysis, the sole significant predictive factor for the LBR was the transfer of blastocyst embryos. It is recommended that these results be examined and discussed in future prospective studies with a larger sample size, considering the lack of comparable research in this field.

Effect of progesterone concentration on hCG trigger day on clinical outcomes after high-quality single blastocyst transfer in GnRH antagonist cycles.

To investigate whether progesterone levels on the human chorionic gonadotropin (hCG) trigger day are associated with clinical outcomes in fresh cycles and the first frozen-thawed cycles (the freeze-all strategy) following the transfer of a high-quality single blastocyst. This single-center retrospective analysis was conducted on patients undergoing in vitro fertilization with the gonadotropin-releasing hormone (GnRH) antagonist protocol from January 2017 to December 2023. The study included the first and second oocyte retrieval cycles with progesterone levels ≤2 ng/ml on hCG trigger day. Clinical pregnancy rates and early miscarriage rates were compared among groups using curve fitting, threshold effect analysis, and multivariable regression. When progesterone levels were between 1 and 2 ng/ml, the pregnancy rate in fresh cycles was only 51% of that in cycles with progesterone levels ≤1 ng/ml (95% CI: 0.33, 0.79, p = 0.0028). And the pregnancy rate decreased by 25% (95% CI: 0.51, 1.09) for frozen cycles, although there was no statistically significant (p = 0.1273). When cycle types were used as a binary variable in multivariate regression analysis, it was found that the clinical pregnancy rate in frozen cycles was 1.84 times higher than in fresh cycles (OR = 1.84, 95% CI: 1.38-2.47). For progesterone levels between 1 and 2 ng/ml, the clinical pregnancy rate in frozen cycles was 2.90 times that of fresh cycles (OR = 2.90, 95% CI: 1.59, 5.29, p = 0.0015). Progesterone levels on hCG day had no impact on the clinical pregnancy rate in thaw cycles, nor did they affect miscarriage rates in fresh or thaw cycles (p > 0.05). When progesterone levels on hCG trigger day were between 1 and 2 ng/ml, the clinical pregnancy rate for frozen-thawed cycles of high-quality single blastocyst transfer using an GnRH antagonist protocol significantly surpasses that of fresh cycles, thus elective frozen embryo transfer after the freeze-all strategy is recommended.

GnRH antagonist protocol with hCG triggering ameliorates fertilization defect caused by failure of cumulus cell pentraxin-3 expression in unilateral endometriomas.

The aim of the study was to determine the expression pattern of long pentraxin 3 (PTX3) mRNA in cumulus cells (CCs) isolated from metaphase II oocytes of women with unilateral endometrioma undergoing controlled ovarian stimulation using a gonadotropin-releasing hormone antagonist (GnRHa) protocol. A total of 60 CC samples, 30 from the affected ovary and 30 from the contralateral ovary, were collected from 12 patients with unilateral endometrioma who underwent flexible GnRHa protocol with recombinant human chorionic gonadotropin (rhCG) trigger. Thirty CC samples collected from the left ovary of 12 women with male factor infertility were used as external controls. Long PTX3 mRNA expression in each group was analyzed by real-time polymerase chain reaction (RT-PCR). Relative gene expression (fold-change) was calculated according to the 2-ΔΔCt equation. Fertilization rates after intracytoplasmic sperm injection (ICSI) were recorded for each group. CC-PTX3 mRNA expression in the unilateral endometrioma group was significantly lower than the mRNA expression of the disease-free ovary (0.90±0.01 vs. 0.25±0.02, p<0.01). CC-PTX3 mRNA expression of MII oocytes of the disease-free ovary was found to be similar to the control group (1.02±0.03 vs. 0.90±0.01, p=0.107). A significant 3.6-fold downregulation was observed in the CC-PTX3 mRNA expression of the endometrioma group compared to the CC-PTX3 mRNA expression in the contralateral ovary. CC-PTX3 mRNA expression in the endometrioma group was downregulated 4.08-fold compared to the CC-PTX3 mRNA expression of the control group (1.02±0.03 vs. 0.25±0.02, p<0.001). The cumulus morphologies of the endometrioma group with low CC-PTX3 expression and the groups with normal CC-PTX3 levels were similar. Fertilization rates of the endometrioma group were similar to the contralateral ovary and control groups. Unilateral endometrioma reduces CC-PTX3 expression but does not affect disease-free ovaries. The GnRHa protocol improved the fertilization rates, suggesting that failed CC-PTX3 expression is an in vivo pathology.

Effect of estradiol supplementation on luteal support following a significant reduction in serum estradiol levels after hCG triggering: a prospective randomized controlled trial

ObjectiveThis study aimed to evaluate the impact of adding 4 mg estradiol valerate to progesterone for luteal support on pregnancy rates in IVF cycles following a long protocol with reduced luteal serum estradiol levels post-hCG triggering.Design, setting, and participantsThe prospective randomized controlled trial was conducted at a public tertiary hospital reproductive center with 241 patients who experienced a significant decrease in serum estrogen levels post-oocyte retrieval.InterventionsParticipants received either a daily 4 mg dose of estradiol valerate in addition to standard progesterone or standard progesterone alone for luteal support.ResultsThe ongoing pregnancy rate did not show a significant difference between the E2 group and the control group (56.6% vs. 52.2%, with an absolute rate difference (RD) of 4.4%, 95% CI -0.087 to 0.179, P = 0.262). Similarly, the live birth rate, implantation rate, clinical pregnancy rate, early abortion rate, and severe OHSS rate were comparable between the two groups. Notably, the E2 group had no biochemical miscarriages, contrasting significantly with the control group (0.0% vs. 10.7%, RD -10.7%, 95% CI -0.178 to -0.041, P = 0.000). In the blastocyst stage category, the clinical pregnancy rate was notably higher in the E2 group compared to the control group (75.6% vs. 60.8%, RD 14.9%, 95% CI 0.012 to 0.294, P = 0.016).ConclusionAdding 4 mg estradiol valerate to progesterone for luteal support does not affect the ongoing pregnancy rate in embryo transfer cycles using a long protocol with a significant decrease in serum estradiol levels after hCG triggering. However, it may reduce biochemical miscarriages and positively impact clinical pregnancy rates in blastocyst embryo transfer cycles.Trial registrationChiCTR1800020342.

Use of hCG for luteal support in natural frozen-thawed blastocyst transfer cycles: a cohort study.

In the realm of natural frozen-thawed embryo transfer (FET) cycles, the application of luteal phase support (LPS) is a prevalent practice, primarily due to its beneficial impact on reproductive outcomes. Among the various LPS medications, human chorionic gonadotropin (hCG) is one that exerts its function on both the corpus luteum and the endometrium. To evaluate the effect of hCG administration as LPS on reproductive outcomes in natural FET cycles. This study was a retrospective cohort analysis conducted at a tertiary care hospital. It included women who underwent natural FET treatment from January 2018 to December 2022. Participants were divided into the hCG LPS group and the non-hCG LPS group on the basis of whether they used hCG as LPS after blastocyst transfer. The primary outcome was the clinical pregnancy and live birth rates. The secondary outcomes included the early miscarriage rate (before 12th gestational week) and total miscarriage rate. A total of 4762 women were included in the analysis, and 1910 received hCG LPS and 2852 received no hCG LPS (control group). In the general cohort, the clinical pregnancy and live birth rates in the hCG LPS group were significantly lower than those in the control group (63.82% vs 66.41%, aOR 0.872, 95% CI 0.765-0.996, P=0.046; 53.98% vs 57.15%, aOR 0.873, 95% CI 0.766-0.991, P=0.035, respectively). The early miscarriage and total miscarriage rates were similar between the two groups. In a subgroup analysis, in women who received an hCG trigger, there was no significant difference in the clinical pregnancy rate or live birth rate between the two groups. However, in women who ovulated spontaneously, the clinical pregnancy and live birth rates in the hCG LPS group were significantly lower than those in the control group (60.99% vs 67.21%, aOR 0.786, 95% CI 0.652-0.946, P=0.011; 50.56% vs 57.63%, aOR 0.743, 95% CI 0.619-0.878, P=0.001, respectively). Among women undergoing natural cycle frozen-thawed blastocyst transfer, hCG LPS is associated with lower clinical pregnancy and live birth rates. Additionally, the adverse effect of hCG LPS is more pronounced in women who ovulate spontaneously.

Effect of prematurely elevated late follicular progesterone on pregnancy outcomes following ovarian stimulation-intrauterine insemination for unexplained infertility: secondary analysis of the AMIGOS trial.

What is the relationship between late follicular phase progesterone levels and clinic pregnancy and live birth rates in couples with unexplained infertility undergoing ovarian stimulation with IUI (OS-IUI)? Late follicular progesterone levels between 1.0 and <1.5 ng/ml were associated with higher live birth and clinical pregnancy rates while the outcomes in groups with higher progesterone levels did not differ appreciably from the <1.0 ng/ml reference group. Elevated late follicular progesterone levels have been associated with lower live birth rates after fresh embryo transfer following controlled ovarian stimulation and egg retrieval, but less is known about whether an association exists with outcomes in OS-IUI cycles. Existing studies are few and have been limited to ovarian stimulation with gonadotrophins, but the use of oral agents, such as clomiphene citrate and letrozole, is common with these treatments and has not been well studied. The study was a prospective cohort analysis of the Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation (AMIGOS) randomized controlled trial. Frozen serum was available for evaluation from 2121 cycles in 828 AMIGOS participants. The primary pregnancy outcome was live birth per cycle, and the secondary pregnancy outcome was clinical pregnancy rate per cycle. Couples with unexplained infertility in the AMIGOS trial, for whom female serum from day of trigger with hCG was available in at least one cycle of treatment, were included. Stored frozen serum samples from day of hCG trigger during treatment with OS-IUI were evaluated for serum progesterone level. Progesterone level <1.0 ng/ml was the reference group for comparison with progesterone categorized in increments of 0.5 ng/ml up to ≥3.0 ng/ml. Unadjusted and adjusted risk ratios (RR) and 95% CI were estimated using cluster-weighted generalized estimating equations to estimate modified Poisson regression models with robust standard errors. Compared to the reference group with 110/1363 live births (8.07%), live birth rates were significantly increased in cycles with progesterone 1.0 to <1.5 ng/ml (49/401 live births, 12.22%) in both the unadjusted (RR 1.56, 95% CI 1.14, 2.13) and treatment-adjusted models (RR 1.51, 95% CI 1.10, 2.06). Clinical pregnancy rates were also higher in this group (55/401 clinical pregnancies, 13.72%) compared to reference group with 130/1363 (9.54%) (unadjusted RR 1.46, 95% CI 1.10, 1.94 and adjusted RR 1.42, 95% CI 1.07, 1.89). In cycles with progesterone 1.5 ng/ml and above, there was no evidence of a difference in clinical pregnancy or live birth rates relative to the reference group. This pattern remained when stratified by ovarian stimulation treatment group but was only statistically significant in letrozole cycles. The AMIGOS trial was not designed to answer this clinical question, and with small numbers in some progesterone categories our analyses were underpowered to detect differences between some groups. Inclusion of cycles with progesterone values above 3.0 ng/ml may have included those wherein ovulation had already occurred at the time the IUI was performed. These cycles would be expected to experience a lower success rate but pregnancy may have occurred with intercourse in the same cycle. Compared to previous literature focusing primarily on OS-IUI cycles using gonadotrophins, these data include patients using oral agents and therefore may be generalizable to the wider population of infertility patients undergoing IUI treatments. Because live births were significantly higher when progesterone ranged from 1.0 to <1.5 ng/ml, further study is needed to clarify whether this progesterone range may truly represent a prognostic indicator in OS-IUI cycles. Oklahoma Shared Clinical and Translational Resources (U54GM104938) National Institute of General Medical Sciences (NIGMS). AMIGOS was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development: U10 HD077680, U10 HD39005, U10 HD38992, U10 HD27049, U10 HD38998, U10 HD055942, HD055944, U10 HD055936, and U10HD055925. Research made possible by the funding by American Recovery and Reinvestment Act. Dr Burks has disclosed that she is a member of the Board of Directors of the Pacific Coast Reproductive Society. Dr Hansen has disclosed that he is the recipient of NIH grants unrelated to the present work, and contracts with Ferring International Pharmascience Center US and with May Health unrelated to the present work, as well as consulting fees with May Health also unrelated to the present work. Dr Diamond has disclosed that he is a stockholder and a member of the Board of Directors of Advanced Reproductive Care, Inc., and that he has a patent pending for the administration of progesterone to trigger ovulation. Dr Anderson, Dr Gavrizi, and Dr Peck do not have conflicts of interest to disclose. N/A.

Co-administration of GnRH-agonist and hCG (double trigger) for final oocyte maturation increases the number of top-quality embryos in patients undergoing IVF/ICSI cycles

BackgroundThe utilization of a double trigger, involving the co-administration of gonadotropin-releasing hormone agonist (GnRH-a) and human chorionic gonadotropin (hCG) for final oocyte maturation, is emerging as a novel approach in gonadotropin-releasing hormone antagonist (GnRH-ant) protocols during controlled ovarian hyperstimulation (COH). This protocol involves administering GnRH-a and hCG 40 and 34 h prior to ovum pick-up (OPU), respectively. This treatment modality has been implemented in patients with low/poor oocytes yield. This study aimed to determine whether the double trigger could improve the number of top-quality embryos (TQEs) in patients with fewer than three TQEs.MethodsThe stimulation characteristics of 35 in vitro fertilization (IVF) cycles were analyzed. These cycles were triggered by the combination of hCG and GnRHa (double trigger cycles) and compared to the same patients’ previous IVF attempt, which utilized the hCG trigger (hCG trigger control cycles). The analysis involved cases who were admitted to our reproductive center between January 2018 and December 2022. In the hCG trigger control cycles, all 35 patients had fewer than three TQEs.ResultsPatients who received the double trigger cycles yielded a significantly higher number of 2PN cleavage embryos (3.54 ± 3.37 vs. 2.11 ± 2.15, P = 0.025), TQEs ( 2.23 ± 2.05 vs. 0.89 ± 0.99, P < 0.001), and a simultaneously higher proportion of the number of cleavage stage embryos (53.87% ± 31.38% vs. 39.80% ± 29.60%, P = 0.043), 2PN cleavage stage embryos (43.89% ± 33.01% vs. 27.22% ± 27.13%, P = 0.014), and TQEs (27.05% ± 26.26% vs. 14.19% ± 19.76%, P = 0.019) to the number of oocytes retrieved compared with the hCG trigger control cycles, respectively. The double trigger cycles achieved higher rates of cumulative clinical pregnancy (20.00% vs. 2.86%, P = 0.031), cumulative persistent pregnancy (14.29% vs. 0%, P < 0.001), and cumulative live birth (14.29% vs. 0%, P < 0.001) per stimulation cycle compared with the hCG trigger control cycles.ConclusionCo-administration of GnRH-agonist and hCG for final oocyte maturation, 40 and 34 h prior to OPU, respectively (double trigger) may be suggested as a valuable new regimen for treating patients with low TQE yield in previous hCG trigger IVF/intracytoplasmic sperm injection (ICSI) cycles.

O-017 Swim-up versus density gradients for sperm preparation in intrauterine insemination: a multi-centre randomised clinical trial

Abstract Study question What is the effectiveness of swim-up (SU) and density gradients (DG) for sperm preparation in infertile couples undergoing intrauterine insemination (IUI)? Summary answer In couples undergoing IUI, there is no significant difference in the treatment outcomes between SU and DG. What is known already Swim-up (SU) and density gradients (DG) are the most two commonly used techniques for sperm preparation in intrauterine insemination (IUI). The latest Cochrane review concluded that there is uncertainty about the effectiveness of SU versus DG and no studies reported on live birth. Study design, size, duration This open-label, multi-centre randomised clinical trial was conducted on 912 infertile couples at a tertiary IVF center, Ho Chi Minh City, Vietnam from August 2020 to June 2023. Couples were randomly asigned to two groups, SU and DG using computerized randomisation on the day of IUI with variable block size of 2, 4 or 6. Primary outcome was live birth rate. Participants/materials, setting, methods Infertile couples were eligible if aged ≥18, indicated for IUI with ≤2 IUI prior attempts and husbands’ sperm concentration ≥5x106/ml, progressive motility (PR) ≥32% and total PR sperm count &amp;gt;5x106 before sperm preparation (WHO 2010 criteria). Couples using frozen semen, or high viscosity semen were not eligible. Women had ovulation induction using hMG. Sperm preparation was performed within one hour after ejaculation. IUI was performed once at 36 to 40 hours after hCG trigger. Main results and the role of chance Between August 2020 and June 2023, 912 couples were randomly assigned to SU (n = 456) or DG (n = 456). Baseline characteristics were comparable between the two groups (mean female age of 31.3 ± 0.4 years; total sperm count: 86.2 [52.9;137.6] million; sperm motility: 44.8 ± 8.2%). Live birth occurred in 55 (12.1%) couples in the SU group and 71 (15.7%) couples in the DG group (RR 0.77; 95% CI 0.56-1.07). Ongoing pregnancy and multiple pregnancy were also comparable between the two groups. There were no statistically significant differences between the SU and DG groups with respect to the occurrence of pregnancy complications, obstetric and perinatal complications, preterm delivery, birth weight and neonatal complications. Pre-planned subgroup analysis showed that the live birth rate was not materially affected by the IUI indications, total motile sperm after preparation (&amp;lt;1, ≥1 and &amp;lt;5, ≥5 and &amp;lt;10 and ≥10 million). Limitations, reasons for caution The main limitation of the study was its open-label design, due to the nature of the interventions. Wider implications of the findings Our study suggests that in couples undergoing IUI with progressive motility (PR) ≥32% and total PR sperm count &amp;gt;5x106 before sperm preparation, SU or DG can both be used for sperm preparation, with a preference for density gradients. Trial registration number NCT04477356

P-612 Euploidy rates between cycles triggered with gonadotrophin-releasing hormone agonist (GnRHa), human chorionic gonadotrophin (hCG) and dual trigger

Abstract Study question Is there any difference in euploidy rates between in vitro fertilization (IVF) cycles triggered with GnRHa, hCG or dual trigger? Summary answer There is no difference in the euploidy rate in preimplantation genetic testing for aneuploidy (PGT-A) cycles according to the trigger method used. What is known already The use of PGT-A has shown that the success of meiosis in the IVF laboratory is inversely correlated with maternal age. However, other uninvestigated factors involved in the IVF process may interfere with normal oocyte physiology. Since the final maturation obtained after ovarian stimulation depends on the use of drugs to promote the resumption of meiosis, it is worth investigating whether the triggering method could impact on oocyte and embryo euploidy. This study aims is to evaluate differences in embryo euploidy rates between PGT-A cycles triggered with GnRHa, hCG or dual trigger (GnRHa + hCG). Study design, size, duration This is a single-center retrospective study of 934 patients who underwent 1085 PGT-A cycles by Next-Generation Sequencing (NGS) from January 2017 to December 2023, using one of three possible trigger methods to induce final oocyte maturation: GnRHa, hCG, or dual trigger. The couples included in the study had normal karyotypes and no severe male factor. Participants/materials, setting, methods Data on the number of oocytes retrieved, ratio of metaphase II (MII) oocytes and fertilization rate, blastocyst development and embryo euploidy were assessed and compared between the GnRHa, hCG and dual trigger treatments. A secondary analysis was performed to evaluate data stratified by patient age. Main results and the role of chance A total of 1085 PGT-A cycles involving 934 patients (38.07 ± 3.01 years) and 2803 biopsied blastocysts were included in the analysis. Dual trigger was used in 726 (77.73%) cycles, GnRHa in 287 (26,4%) cycles and hCG in 72 (7.71%) cycles. The number of oocytes retrieved was significantly higher in the GnRHa group (GnRHa: 18.72 ± 8.59; hCG: 9.88 ± 5.64; dual trigger: 10.58 ± 5.65; p &amp;lt; 0.001) with similar maturation rate (GnRHa: 77.46%; hCG: 74.58%; dual trigger: 76.03%; p = 0.789), fertilization rate (GnRHa: 78.12%; hCG: 76.37%; dual trigger: 79.12%; p = 0.168), blastulation rate (GnRHa: 61.03%; hCG: 58.32%; dual trigger: 58.73%; p = 0,629), high-quality blastocyst rate (GnRHa: 27,88%; hCG: 33,67%; dual trigger: 27,88%; p = 0.543) and embryo euploidy per biopsied embryo (GnRHa: 42.48%; hCG:45.49%; dual trigger:46.98%; p = 0.112). Analysis of the data stratified by age showed similar rates of euploidy rates with the three trigger methods in women younger than 41 years (&amp;lt;35 years: GnRHa 66.50%; hCG 66.67%; dual trigger 56.97% p = 0.290; 35-37 years: GnRHa 49.45% hCG 51.04%; dual trigger 50.23%; p = 0.988; 38-40 years: GnRHa 40.93%; hCG 41.27%; dual trigger 39.13% p = 0.257). However, in patients ≥41 years old the euploidy rate was statistically higher in the GnRHa group (GnRH 31.51%; hCG 18.75%; dual trigger 16.89%; p = 0.032). Limitations, reasons for caution The main limitations of the study are: its retrospective design, the possibility that the trigger method was chosen based on the ovarian response and the limited number of patients in both the hCG trigger and women ≥ 41 years groups. Wider implications of the findings Our results suggest that triggering with GnRHa, hCG or dual trigger leads to comparable euploidy rates. Triggering with GnRHa should be recommended in older patients since it has been associated with a higher rate of embryonic euploidy. Trial registration number Not Applicable

P-418 What is the optimal midluteal phase circulating progesterone level during a fresh IVF cycle? The answer differs from what one expects in a natural cycle

Abstract Study question Do midluteal phase circulating progesterone (P4) levels relate to the fresh embryo transfer clinical outcome and is rescue P4 useful in such cases? Summary answer Live birth rate (LBR) was significantly lower when P4 levels were below 20ng/ml and did not seem to benefit from rescue intramuscular P4. What is known already Preceding literature on the predictive value of midluteal P4 for LBR has shown conflicting results and frequently included small sample sets and heterogeneous ovarian stimulation protocols. The findings reported ranged from the lack of an association between P4 serum levels and clinical outcome to worse success rates seen either in the groups with the highest or the lowest P4 in midluteal phase. Furthermore, while rescue P4 has been empirically proposed, it has lacked formal assessment thus far. Study design, size, duration In total, 652 patients who underwent a fresh single blastocyst transfer in an IVF cycle in our center between 2014 and 2021 were included in this retrospective cohort study. All were GnRH-antagonist cycles using hCG trigger and luteal support with micronized vaginal progesterone 200mg twice daily. Rescue intramuscular progesterone was systematically administered whenever low midluteal P4 (below 1 standard deviation of the center’s mean) levels were detected. Participants/materials, setting, methods The cycles were subdivided into three groups according to the midluteal P4 levels: &amp;lt;10ng/ml, 10-20ng/ml and &amp;gt;20ng/ml. The primary outcome assessed was LBR, with secondary outcomes including clinical pregnancy (CPR) and pregnancy loss rates. Maternal age and body mass index (BMI), year of treatment, ovarian response, endometrial thickness, cause of infertility and embryo quality were controlled for using multivariable logistic regression. Main results and the role of chance The mean age ± standard deviation of patients was 36.8±3.8 years, while mean weight and BMI were 63.2±11.5kg and 23.3±3.9kg/m2, respectively. LBR in the group with P4&amp;gt;20ng/ml (46.5%) was significantly higher than in the groups with low and intermediate P4 serum levels (23.1% and 28.1%, respectively, p &amp;lt; 0.001). The same was true for CPR (54.5%, 30.8% and 37.9%, respectively, p &amp;lt; 0.001). Conversely, the rate of pregnancy loss in the group with P4&amp;gt;20ng/ml (23.8%) was significantly lower than in the groups with low and intermediate P4 levels (42.6% and 37.5%, respectively, p = 0.018). The multivariable logistic regression confirmed that, after controlling for the confounding variables described above, P4&amp;gt;20ng/ml remained significantly associated with a higher LBR (OR: 2.285; 95% CI: 1.506-3.469) and a lower pregnancy loss rate (OR: 0.488; 95% CI: 0.273-0.873), irrespective of the use of rescue IM P4. Finally, a multivariable linear regression analysis of the patients baseline characteristics suggested that the only parameter predictive of midluteal P4 levels was the female patients’ weight, with an inverse relationship (adjusted regression coefficient: -0,012; 95% CI: -0,016/-0,009). Limitations, reasons for caution As the pituitary suppression, ovulation trigger and luteal support protocols used in the cycles included in the study were homogeneous (in order to maximize the internal validity of the results), this limits the extrapolibility of the results to other stimulation protocols. Furthermore, we caution that this is a retrospective study. Wider implications of the findings The usefulness of both midluteal P4 serum measurements and rescue P4 should continue to be assessed. The reasons behind the need for higher levels of P4 in a fresh cycle, when compared to natural cycles, must also be investigated. Luteal support may require personalization according to female body weight. Trial registration number Not Applicable

P-388 The science of frozen embryo transfer, is modified natural cycle better?

Abstract Study question Do live birth rate, obstetric outcomes and number of clinic visits differ between frozen embryo transfer in modified natural and artificial cycle? Summary answer Modified natural cycle yielded a higher live birth rate for the similar number of visits, less hypertension, but higher rate of gestational diabetes. What is known already A frozen embryo transfer in a modified natural cycle entails procedure timing such that it coincides with the woman’s ovulatory cycle. Conversely, a frozen embryo transfer in an artificial cycle involves controlled hormonal stimulation, with the subsequent scheduling of embryo transfer. Based on the current evidence, there is no difference in pregnancy rates between modified natural cycle and artificial cycle. Frozen embryo transfer during an artificial cycle allows for greater flexibility for the patient and physicians. However, it seems to be associated with higher risk of adverse obstetric and neonatal outcomes. Study design, size, duration 1206 frozen embryo transfer cycles between January 1st, 2022, and December 31st, 2022 were retrospectively studied. Patients older than 40, with recurrent implantation failure, and recurrent pregnancy loss were excluded. Patients were divided according to their age, BMI, AMH, and the type of embryo transfer protocol. Compared outcomes were endometrial thickness, biochemical pregnancy rate, clinical pregnancy rate, miscarriage rate, number of clinic visits prior to transfer, obstetric complications, livebirth rate, and livebirth weight. Participants/materials, setting, methods Patients in the modified natural cycle group were followed by ultrasound and when the endometrium reached a thickness ≥ 7mm, and a dominant follicle ≥ 15 mm, HCG trigger was given, and the embryo (blastocyst) transferred 7 days later. In the artificial cycle group, patients received estrogen supplementation either orally or by patches and when the endometrium reached a thickness ≥ 7 mm, embryo transfer was scheduled following intramuscular progesterone administration for 6 days. Main results and the role of chance Patients with modified natural cycle (n = 250) embryo transfers have better clinical pregnancy rate compared to the embryo transfers (n = 250) in artificial cycles (63,6% vs 55,2% p = 0,05), and significantly better live birth rate (57,2% vs 43,9% p = 0,003) despite similar biochemical pregnancy rate (64% vs 61% p = 0,48). The miscarriage rate was significantly lower in modified natural compared to artificial cycles (10,2 % vs 20,99%, p = 0,008). Similar results were found with the transfer of PGTA tested embryos. There was no difference in the endometrial thickness between the 2 groups. The number of visits was higher in the modified natural cycle group, but the difference was not clinically significant (1,57 days vs 1,2 days). When comparing the obstetric outcomes, patients with a modified natural cycle transfer had a lower risk of hypertension (6,6% vs 13,5 % p = 0,10), but a significantly higher risk of gestational diabetes (19% vs 8,3% p = 0,02). No difference was observed regarding the birth weight, percentage of preterm birth or mode of delivery. Regression analysis was performed to identify any cofounder that might have affected the clinical pregnancy rate, and the results showed that the type of transfer was the only factor affecting the outcomes (OR: 1,23 CI: 1,03- 1,46) Limitations, reasons for caution The main limitation of this study is its retrospective nature. A randomized controlled study should be performed to confirm these findings. Wider implications of the findings Modified natural embryo transfer could be used to improve pregnancy outcomes. With proper scheduling, embryo transfer could be done with a similar number of visits for modified natural cycles and artificial cycles. More studies are needed to assess the increased risk of gestational diabetes with natural cycle embryo transfer. Trial registration number NCT06053827

P-723 Egg-conomized frozen embryo transfer

Abstract Study question Is home-based monitoring of ovulation cost effective compared with hospital-controlled ovulation in women undergoing frozen embryo transfer in the natural cycle? Summary answer Home-based monitoring to time frozen-embryo-transfer is cost-effective compared to hospital-controlled ovulation, as it results in lower cost with no difference in ongoing pregnancy rates. What is known already Women undergoing frozen embryo transfer treated by home-based monitoring of ovulation or hospital-controlled ovulation have comparable ongoing pregnancy rates. We found no differences in secondary outcomes, including the risk of undetected ovulation. Complete home-based monitoring of ovulation with LH hormone kits is feasible and requires no hospital visits at lower costs since ultrasound monitoring and hCG injection are no longer needed. Both consequences imply potentially lower costs after home-based monitoring of ovulation. Study design, size, duration We performed an economic evaluation of home-based monitoring of ovulation compared with hospital-controlled ovulation in a national multicentre randomised controlled trial in women undergoing frozen embryo transfer (ANTARCTICA-2 RCT Dutch TrialRegister Trial NL6414). 1464 women were randomly assigned between April 10, 2018, and April 13, 2022, with 732 allocated to home-based monitoring and 732 to hospital-controlled monitoring. All randomized patients were included according to the intention-to-treat principle. Participants/materials, setting, methods We performed a cost-effectiveness analysis from a hospital and societal perspective. We compared the direct medical costs of home-based monitoring of ovulation and hospital-controlled ovulation during one cycle until an ongoing pregnancy occurred. Direct medical costs included digital ovulation tests, transvaginal ultrasound monitoring of the dominant follicle followed by hCG trigger, hormone measurements in blood, treatment for miscarriage or ectopic pregnancy. Nonparametric bootstrapping was used to calculate cost estimates and differences with 95% confidence intervals. Main results and the role of chance Ongoing pregnancy rates were 20·8% in the home-based monitoring group and 20·9% in the hospital-controlled group (risk ratio [RR] 0·99 [90% CI 0·81 to 1·22]; risk difference [RD] -0·14 [90% CI -3·63 to 3·36]). No differences in ectopic pregnancies or miscarriages were found. Home-based monitoring required less travelling to the hospital, less ultrasounds by doctors or nurses, less hormone measurements in blood, and less medication (hCG injections). Mean direct medical costs per woman in the home-based monitoring of ovulation group and in the hospital-controlled ovulation group were €752 versus €991, respectively, with a mean difference of €239. The ICER consistently showed home-based monitoring to be less costly with no difference in effectiveness. Consequently, the cost difference from a societal perspective was larger. The mean costs per woman in the home-based monitoring of ovulation group and in the hospital-controlled ovulation group were €787 versus €1395, respectively, with a mean difference of €607 in favour of home-based monitoring. Limitations, reasons for caution We report on one cycle per women. Women usually undergomultiple frozen-embryo-cycles. This is of importance for clinical decision making aboutimplementation of home-based monitoring, since the cumulative benefit of multiple cycles perwoman should be taken into account. Wider implications of the findings The results of our trial show that home-based monitoring time frozen embryo transfer is equally effective but less costly compared with hospital-controlled ovulation. In this era of climate change and shortages of hospital staff and waiting lists, any process that takes less human labour is important. Trial registration number Dutch Trial Register (Trial NL6414)

P-639 Are GnRH-agonists (GnRH-a) safer and more effective ovulation triggers than human chorionic gonadotrophin (hCG)? A retrospective analysis of frozen embryo replacement cycle (FERC) outcomes

Abstract Study question Are GnRH-agonists (GnRH-a) safer and more effective ovulation triggers than human chorionic gonadotrophin (hCG)? A retrospective analysis of frozen embryo replacement cycle (FERC) outcomes Summary answer GnRH-a trigger reduces the incidence and severity of ovarian hyperstimulation syndrome (OHSS) leading to significantly improved clinical outcomes when compared to hCG trigger for FERCs. What is known already Ovulation induction plays a crucial role in the success and safety of ART cycles. hCG is extensively used as an alternative to LH to trigger ovulation. However, high levels of sustained hCG exposure increases the risk of OHSS, a potentially life-threatening complication of ART. To eliminate the risk and incidence of OHSS, GnRH-a can be used to trigger ovulation. Although there are concerns regarding clinical outcomes with fresh transfers following GnRH-a trigger, it elicits a more physiological response compared to hCG. This may lead to improved embryo quality, utilisation, and better clinical outcomes following a freeze-all strategy, reducing patients’ time-to-pregnancy. Study design, size, duration This was a retrospective data analysis of FERC outcomes following fresh IVF or ICSI cycles, involving ovulation induction using either hCG or GnRH-a as a final trigger. The evaluation included results from cycles spanning an eight-year period, from January 2012 to December 2019 at Hammersmith Hospital London. A total of 160 cycles were included in the study, with 76 in the hCG trigger group and 84 in the GnRH-a trigger group. Participants/materials, setting, methods Strict inclusion criteria were employed to render the study groups as comparable as possible and to minimise the effect of independent variables, such as oocyte and sperm factors, on oocyte or embryo developmental competence. Inclusion criteria: women ≤37 years old at the start of treatment, GnRH antagonist stimulation, blastocyst vitrification-warming and transfers only. Statistical significance was calculated using independent t-test and Fisher’s Chi-square exact test. Main results and the role of chance The mean age (±SD) of patients at the time of oocyte retrieval was comparable across groups. The average number of oocytes collected were significantly higher in the GnRH-a group compared to hCG (28.31 vs. 18.07, respectively, P &amp;lt; 0.001). Embryological data (maturation, fertilisation, blastocyst formation, blastocyst utilisation and good quality blastocyst formation rates) were comparable across both groups. OHSS rate was significantly lower in the GnRH-a group (17% vs. 50%. P &amp;lt; 0.0001). The following clinical data were significantly higher (P &amp;lt; 0.05) in the GnRH-a group compared to hCG: implantation rate (56% vs. 36%), clinical pregnancy rate (56% vs. 36%) and live birth rate (42% vs. 27%). Limitations, reasons for caution The biggest limitation of this study is its retrospective nature and the application of various inclusion-exclusion criteria that have resulted in relatively small sample sizes. Additionally, numerous other confounders, e.g. patient body mass index, cause/duration of infertility and stimulation duration, have not been considered in this study. Wider implications of the findings The findings of this study are promising and demonstrate a great potential for benefit in the use of GnRH-a trigger with a freeze-all strategy to minimise the risk of OHSS, diminishing the associated patient morbidity and mortality, reducing healthcare costs, improving clinical outcomes, and reducing the overall time-to-pregnancy for patients. Trial registration number not applicable

P-610 Elevated/high-normal TSH on day of beta-hCG in sub-clinical hypothyroid patients on levothyroxine associated with better odds of pregnancy in IVF cycles: a nested case-control study

Abstract Study question Is there an association between odds of achieving pregnancy and high-normal/elevated TSH levels in sub-clinical hypothyroid (SCH) patients on levothyroxine replacement who are undergoing IVF? Summary answer Odds of achieving pregnancy are significantly greater when TSH on day of beta-hCG is elevated/high-normal despite levothyroxine replacement in sub-clinical hypothyroid (SCH) patients undergoing IVF. What is known already TSH levels are known to increase following ovarian stimulation (OS). A 2023 Nature publication reported that in euthyroid patients undergoing fresh embryo transfer following OS and IVF, elevated/high-normal TSH levels (&amp;gt;2.5 mIU/mL) are associated with better pregnancy rates. Another recent study found no differences in IVF outcomes between SCH patients whose TSH was maintained=/&amp;lt; 4.2 mIU/mL on levothyroxine vs euthyroid controls. To the best of our knowledge, there are no prospective studies investigating possible association between pregnancy outcome and elevated TSH levels following OS within a cohort of SCH patients on levothyroxine replacement, using 2.5 mIU/mL as a strict cut-off. Study design, size, duration Nested case-control study performed between July-December 2023. PCOS and other endocrinopathies excluded. 100 SCH patients booked for fresh, blastocyst eSET cycles initially recruited after thyroxine replacement. 79 patients completed the study following 5 drop-outs and 16 cases of cycle cancellation/failure, cleavage-stage transfers and freeze-all. Odds of achieving pregnancy (‘cases’) in patients with elevated/high-normal TSH (‘exposure’) on day of beta-hCG determined by Odds Ratio, with beta-hCG negative patients serving as ‘controls’. First IVF cycle data analysed/presented. Participants/materials, setting, methods Study performed at an university-affiliated ART institute. Following institutional ethical clearance, patients with SCH (TSH&amp;gt;2.5 mIU/mL) recruited after informed consent. Levothyroxine replacement initiated to achieve TSH:0.5-2.5 mIU/mL and continued; followed by OS, antagonist IVF/ICSI cycles, hCG trigger and fresh blastocyst eSET. TSH measured again on day of beta-hCG (blinded). Odds Ratio calculated (IBM SPSS V.26) to determine odds of achieving pregnancy in high-normal/elevated group (TSH&amp;gt;2.5 mIU/mL) compared to low-normal group (TSH =/&amp;lt; 2.5 mIU/mL). Main results and the role of chance Baseline demographic characteristics of the single starting cohort of sub-clinical hypothyroid patients undergoing IVF/ICSI (n = 79) are summarized as mean±SD- age: 31.7±4.9 years, BMI: 27.9±14.2 kg/m2, AMH: 3.1±2.4 ng/mL, TSH before levothyroxine replacement: 5.5±2.7 mIU/mL. Data analysis showed that out of 63 patients in whom TSH level elevated &amp;gt; 2.5 mIU/mL on day of beta-hCG, 33 became pregnant (P.R- 52.4%); and out of 16 patients in whom TSH remained =/&amp;lt; 2.5 mIU/mL on day of beta-hCG, 3 became pregnant (P.R- 18.8%). Statistical analysis further revealed that odds of achieving pregnancy in elevated/high-normal TSH group was almost 5 times compared to odds of achieving pregnancy in low-normal TSH group (OR = 4.77, C.I= 1.24-18.37, at 95% confidence), considering TSH values on day of beta-hCG. Mean TSH in pregnant group (n = 36) was also found to be higher (4.2±1.6 mIU/mL) than mean TSH (3.9±1.9 mIU/mL) in those who did not get pregnant (n = 43). Limitations, reasons for caution Our study is limited by its modest sample size and adequately powered, larger prospective studies are needed before definite conclusions can be drawn from our data. Moreover, being an ongoing study, we do not yet have miscarriage and live-birth data for all patients and thus have not reported the same. Wider implications of the findings To our knowledge, this is the first prospective study documenting association between positive pregnancy outcome and high-normal TSH (using TSH&amp;gt;2.5 mIU/mL as cut-off) in SCH patients having fresh blastocyst eSET. Further investigation is required to determine if high-normal TSH following OS has protective impact on IVF, and its underlying mechanism. Trial registration number not applicable

Intra-Ovarian Platelet-Rich Plasma (PRP) Injection in Management of POSEIDON IV Poor Responders before ICSI: Pilot Study

Abstract Background Poseidon IV poor responders are 35 years old or older women with antral follicle count &amp;lt; 5 and anti-Mullerian hormone &amp;lt; 1.2 ng/ml with cumulative live birth rate (CLBR) of 22.34% - 34.46% following ICSI. Aim of the Work To assess the effectiveness of intra-ovarian platelet-rich plasma (PRP) injection in POSEIDON IV poor responders before ICSI. Patients and Methods This study was conducted on women complaining from infertility at assisted reproductive techniques unit at Ain Shams University Maternity Hospital at the period from March 2021 till January 2022. We got a 55 cases matching the inclusion and exclusion criteria among them 25 cases accepted to participate as the study group (PRP group) and the others 30 cases refused to the participate PRP group and they were enrolled as a control group. Results Endometrium thickness at day of HCG trigger was statistically significantly higher among PRP group than among control group. Ovulation statistically was non-significantly more frequent among PRP group than among control group. Fertilization statistically was non- significantly more frequent among PRP group than among control group. biochemical pregnancy, clinical pregnancy, ongoing pregnancy statistically were non-significantly more frequent among PRP group than among control group. Conclusion According to the finding in this study intra-ovarian platelet-rich plasma (PRP) injection in POSEIDON IV poor responders before ICSI had a non-significant role regarding the laboratory variables and pregnancy outcomes. Hence, further studies are required.

In vitro matured oocytes have a higher developmental potential than in vivo matured oocytes after hormonal ovarian stimulation in Callithrix jacchus

BackgroundThe common marmoset, Callithrix jacchus, is an invaluable model in biomedical research. Its use includes genetic engineering applications, which require manipulations of oocytes and production of embryos in vitro. To maximize the recovery of oocytes suitable for embryo production and to fulfil the requirements of the 3R principles to the highest degree possible, optimization of ovarian stimulation protocols is crucial. Here, we compared the efficacy of two hormonal ovarian stimulation approaches: 1) stimulation of follicular growth with hFSH followed by triggering of oocyte maturation with hCG (FSH + hCG) and 2) stimulation with hFSH only (FSH-priming).MethodsIn total, 14 female marmosets were used as oocyte donors in this study. Each animal underwent up to four surgical interventions, with the first three performed as ovum pick-up (OPU) procedures and the last one being an ovariohysterectomy (OvH). In total, 20 experiments were carried out with FSH + hCG stimulation and 18 with FSH-priming. Efficacy of each stimulation protocol was assessed through in vitro maturation (IVM), in vitro fertilization (IVF) and embryo production rates.ResultsEach study group consisted of two subgroups: the in vivo matured oocytes and the oocytes that underwent IVM. Surprisingly, in the absence of hCG triggering some of the oocytes recovered were at the MII stage, moreover, their number was not significantly lower compared to FSH + hCG stimulation (2.8 vs. 3.9, respectively (ns)). While the IVM and IVF rates did not differ between the two stimulation groups, the IVF rates of in vivo matured oocytes were significantly lower compared to in vitro matured ones in both FSH-priming and FSH + hCG groups. In total, 1.7 eight-cell embryos/experiment (OPU) and 2.1 eight-cell embryos/experiment (OvH) were obtained after FSH + hCG stimulation vs. 1.8 eight-cell embryos/experiment (OPU) and 5.0 eight-cell embryos/experiment (OvH) following FSH-priming. These numbers include embryos obtained from both in vivo and in vitro matured oocytes.ConclusionA significantly lower developmental competence of the in vivo matured oocytes renders triggering of the in vivo maturation with hCG as a part of the currently used FSH-stimulation protocol unnecessary. In actual numbers, between 1 and 7 blastocysts were obtained following each FSH-priming. In the absence of further studies, FSH-priming appears superior to FSH + hCG stimulation in the common marmoset under current experimental settings.

Comparison of HCG Trigger versus Dual Trigger in Improving Pregnancy Outcomes in Patients with Different Ovarian Responses: A Retrospective Study

Comparison of HCG Trigger versus Dual Trigger in Improving Pregnancy Outcomes in Patients with Different Ovarian Responses: A Retrospective Study