OBJECTIVE: Can pregnancy outcomes following fresh elective single embryo transfer (eSET) in gonadotropin-releasing hormone (GnRH) antagonist protocols increase using a gonadotropin (Gn) step-down approach with cessation of GnRH antagonist on the day of hCG administration (hCG day) in patients with normal ovarian response?
CONCLUSIONS: The modified GnRH antagonist protocol using the Gn step-down approach and cessation of GnRH antagonist on the hCG day is effective in improving live birth rates (LBRs) per fresh eSET cycle.
BACKGROUND: Currently, there is no consensus on optimal GnRH antagonist regimens. Studies have shown that fresh GnRH antagonist cycles result in poorer pregnancy outcomes than the long GnRH agonist (GnRHa) protocol. Endometrial receptivity is a key factor that contributes to this phenomenon.
METHODS: An open label randomized controlled trial (RCT) was performed between November 2021 and August 2022. There were 546 patients allocated to either the modified GnRH antagonist or the conventional antagonist protocol at a 1:1 ratio.
METHODS: Both IVF and ICSI cycles were included, and the sperm samples used were either fresh or frozen from the partner, or from frozen donor ejaculates. The primary outcome was the LBRs per fresh SET cycle. Secondary outcomes included rates of implantation, clinical and ongoing pregnancy, miscarriage, and ovarian hyperstimulation syndrome (OHSS), as well as clinical outcomes of ovarian stimulation.
RESULTS: Baseline demographic features were not significantly different between the two ovarian stimulation groups. However, in the intention-to-treat (ITT) population, the LBRs in the modified antagonist group were significantly higher than in the conventional group (38.1% [104/273] vs. 27.5% [75/273], relative risk 1.39 [95% CI, 1.09-1.77], P = 0.008). Using a per-protocol (PP) analysis which included all the patients who received an embryo transfer, the LBRs in the modified antagonist group were also significantly higher than in the conventional group (48.6% [103/212] vs. 36.8% [74/201], relative risk 1.32 [95% CI, 1.05-1.66], P = 0.016). The modified antagonist group achieved significantly higher implantation rates, and clinical and ongoing pregnancy rates than the conventional group in both the ITT and PP analyses (P < 0.05). The two groups did not show significant differences between the number of oocytes retrieved or mature oocytes, two-pronuclear zygote (2PN) rates, the number of embryos obtained, blastocyst progression and good-quality embryo rates, early miscarriage rates, or OHSS incidence rates (P > 0.05).
CONCLUSIONS: A limitation of our study was that the subjects were not blinded to the treatment allocation in the RCT trial. Only women under 40 years of age who had a good prognosis were included in the analysis. Therefore, use of the modified antagonist protocol in older patients with a low ovarian reserve remains to be investigated. In addition, the sample size for Day 5 elective SET was small, so larger trials will be required to strengthen these findings.
CONCLUSIONS: The modified GnRH antagonist protocol using the Gn step-down approach and cessation of GnRH antagonist on hCG day improved the LBRs per fresh eSET cycle in normal responders.
BACKGROUND: This project was funded by grant 2022YFC2702503 from the National Key Research & Development Program of China and grant 2021140 from the Beijing Health Promotion Association. The authors declare no conflicts of interest.
BACKGROUND: The RCT was registered in the Chinese Clinical Trial Registry; Study Number: ChiCTR2100053453.
UNASSIGNED: 21 November 2021.
UNASSIGNED: 23 November 2021.

Does the presence of FSHR single-nucleotide polymorphisms (SNPs) affect late follicular phase progesterone and estradiol serum levels in predicted normoresponders treated with rFSH?
The presence of FSHR SNPs (rs6165, rs6166, rs1394205) had no clinically significant impact on late follicular phase serum progesterone and estradiol levels in predicted normoresponders undergoing a GnRH antagonist protocol with a fixed daily dose of 150 IU rFSH.
Previous studies have shown that late follicular phase serum progesterone and estradiol levels are significantly correlated with the magnitude of ovarian response. Several authors have proposed that individual variability in the response to ovarian stimulation (OS) could be explained by variants in FSHR. However, so far, the literature is scarce on the influence of this genetic variability on late follicular phase steroidogenic response. Our aim is to determine whether genetic variants in the FSHR gene could modulate late follicular phase serum progesterone and estradiol levels.
In this multicenter multinational prospective study conducted from November 2016 to June 2019, 366 patients from Vietnam, Belgium and Spain (166 from Europe and 200 from Asia) underwent OS followed by oocyte retrieval in a GnRH antagonist protocol with a fixed daily dose of 150 IU rFSH. All patients were genotyped for 3 FSHR SNPs (rs6165, rs6166, rs1394205) and had a serum progesterone and estradiol measurement on the day of trigger.
Included patients were predicted normal responder women <38 years old undergoing their first or second OS cycle. The prevalence of late follicular phase progesterone elevation (PE), as well as mean serum progesterone and estradiol levels on the day of trigger were compared between the different FSHR SNPs genotypes. PE was defined as >1.50 ng/ml.
The overall prevalence of PE was 15.8% (n = 58). No significant difference was found in the prevalence of PE in Caucasian and Asian patients (17.5% versus 14.5%). Estradiol levels on the day of trigger and the number of retrieved oocytes were significantly higher in patients with PE (4779 ± 6236.2 versus 3261 ± 3974.5 pg/ml, P = 0.003, and 16.1 ± 8.02 versus 13.5 ± 6.66, P = 0.011, respectively). Genetic model analysis, adjusted for patient age, body mass index, number of retrieved oocytes and continent (Asia versus Europe), revealed a similar prevalence of PE in co-dominant, dominant and recessive models for variants FSHR rs6166, rs6165 and rs1394205. No statistically significant difference was observed in the mean late follicular phase progesterone serum levels according to the genotypes of FSHR rs6166 (P = 0.941), rs6165 (P = 0.637) and rs1394205 (P = 0.114) in the bivariate analysis. Also, no difference was found in the genetic model analysis regarding mean late follicular phase progesterone levels across the different genotypes. Genetic model analysis has also revealed no statistically significant difference regarding mean estradiol levels on the day of trigger in co-dominant, dominant and recessive models for variants FSHR rs6166, rs6165 and rs1394205. Haplotype analysis revealed a statistically significant lower estradiol level on the day of trigger for rs6166/rs6165 haplotypes GA, AA and GG when compared to AG (respectively, estimated mean difference (EMD) -441.46 pg/ml (95% CI -442.47; -440.45), EMD -673.46 pg/ml (95% CI -674.26; -672.67) and EMD -582.10 pg/ml (95% CI -584.92; -579.28)). No statistically significant differences were found regarding the prevalence of PE nor late follicular phase progesterone levels according to rs6166/rs6165 haplotypes.
Results refer to a population of predicted normal responders treated with a normal/low fixed dose of 150 IU rFSH throughout the whole OS. Consequently, caution is needed before generalizing our results to all patient categories.
Based on our results, FSHR SNPs rs6165, rs6166 and rs1394205 do not have any clinically significant impact neither on late follicular phase serum progesterone nor on estradiol levels in predicted normal responders. These findings add to the controversy in the literature regarding the impact of individual genetic susceptibility in response to OS in this population.
This study was supported by an unrestricted grant by Merck Sharp & Dohme (MSD, IISP56222). N.P.P. reports grants and/or personal fees from MSD, Merck Serono, Roche Diagnostics, Ferring International, Besins Healthcare, Gedeon Richter, Organon, Theramex and Institut Biochimique SA (IBSA). C.A. reports conference fees from Merck Serono, Medea and Event Planet. A.R.N., C.B., C.S., P.Q.M.M., H.T., C.B., N.L.V., M.T.H. and S.G. report no conflict of interests related to the content of this article.
NCT03007043.

UNASSIGNED: We aimed to analyze whether elevated progesterone levels on the day before ovulation affected pregnancy outcomes in natural cycles of frozen thawed embryo transfer (NC-FET).
UNASSIGNED: A retrospective analysis was conducted in a public university hospital. Data on clinical pregnancy, live birth, ectopic pregnancy, and miscarriage rates were collected, along with other patient data. Patients were divided into two groups according to their progesterone levels the day before ovulation: the progesterone elevation (PE) group (progesterone level >1.0 ng/mL) and the normal progesterone (NP) group (progesterone level ≤1.0 ng/mL). We assessed the effect of elevated progesterone levels in NC-FET by performing multivariate logistic regression analysis.
UNASSIGNED: Overall 1159 women with tubal factor infertility who underwent NC-FET were enrolled, including 666 women who received cleavage-stage embryo transfers and 493 women who received blastocyst embryo transfers. When two cleavage-stage embryos were transferred, the clinical pregnancy rate was significantly higher in the PE than in the NP group following NC-FET (p < .05). After correcting for various confounders, we found that elevated progesterone levels (adjusted odds ratio [OR]: 1.672; 95% confidence interval [CI]: 1.089-2.566, p = .018) improved the clinical pregnancy rate following transfer of two cleavage-stage embryos but did not affect the pregnancy rate when blastocyst-stage embryos were transferred (adjusted OR: 0.856; 95% CI: 0.536-1.369; p = .517).
UNASSIGNED: The results showed that in patients undergoing cleavage-stage NC-FET, progesterone levels >1.0 ng/mL improved the clinical pregnancy rates. However, the level of progesterone had no effect on the clinical pregnancy rate for patients undergoing blastocyst-stage NC-FET.

BACKGROUND: Evidence regarding impact of pre-ovulatory hormone levels on assisted reproductive technique (ART) outcomes in different ovarian response groups is sparse.
OBJECTIVE: The objective of this study was to evaluate and compare the association between pre-ovulatory hormonal profile and ART outcomes in different ovarian responses.
METHODS: This is a single-centre retrospective cohort study of 273 non-donor fresh ART cycles between January 2013 and June 2016.
METHODS: Data on clinical profile, basal and peak hormonal levels, characteristics of controlled ovarian stimulation and ART outcomes were collected. Progesterone elevation (PE) was defined as pre-ovulatory serum progesterone >1.5 ng/mL or progesterone to oestradiol ratio >1. The association between peak hormonal levels and ART outcomes in poor (≤4 oocytes retrieved), intermediate (5-13 oocytes retrieved) and high (≥14 oocytes retrieved) ovarian responders was analysed and compared.
METHODS: Continuous and categorical variables were summarised as median (interquartile range) and percentages, respectively, and compared using Kruskal-Wallis H-test or Mann-Whitney U-test and Chi-square test or Fisher\'s exact test, respectively.
RESULTS: The incidence of PE, by both criteria and clinical pregnancy rates (35.7%, 36.8% and 18.6% in high, normal and poor responders, respectively; P = 0.073), was similar among the three response groups. Except fertilisation rates in normo-responders, PE did not influence ART outcomes in any response group. Furthermore, there were no differences between peak hormone concentrations or incidence of PE between those who conceived and those who did not.
CONCLUSIONS: Pre-ovulatory sex steroid levels do not seem to be the primary determinant of ART outcomes in any ovarian response category; hence, decision to freeze all embryos in the event of PE should be tailored.

UNASSIGNED: Patients with elevated circulating progesterone concentrations on the day of the human chorionic gonadotropin (hCG) trigger had relatively low implantation rates during assisted reproductive treatments. In this study, we assess the hypothesis that different concentrations of progesterone regulate the expression of homeobox protein A10 (HOXA10) and its downstream genes through miRNA-135a.
UNASSIGNED: MicroRNA-135a (miR-135a), HOXA10, beta3-integrin (ITGβ3), and empty spiracles homeobox-2 (EMX2) expression levels in endometrial tissues from patients with elevated progesterone were measured. To determine the threshold of progesterone level which can impair implantation, Ishikawa cells were used to determine the expression of the aforementioned 4 genes after exposure to 5 graded concentrations of progesterone. The dual-luciferase reporter assay was used to verify whether miR-135a regulated the expression of HOXA10. Furthermore, the effects of HOXA10 on the expression of key endometrial receptivity genes ITGβ3 and EMX2 were confirmed.
UNASSIGNED: High progesterone levels promoted miR-135a expression in vivo, and miR-135a bound to the 3\'-untranslated region (3\'-UTR) of HOXA10 mRNA to inhibit HOXA10 expression. Reduction of HOXA10 promoted EMX2 expression and inhibited ITG-3 production. Progesterone promoted the expression of HOXA10 in vitro at low concentrations. However, when the concentration was greater than 10-7 ng/mL, progesterone inhibited HOXA10 by promoting miR-135a expression, thereby altering the expression of related genes and affecting endometrial receptivity.
UNASSIGNED: In vitro, the trend in miR-135a expression (which first decreased and then increased) was in direct contrast to that of HOXA10 expression (which first increased and then decreased) as progesterone levels increased. The key factors regulating endometrial receptivity included ITGβ3 and EMX2, which were confirmed to be regulated by HOXA10. High progesterone levels affected miR-135a expression, and miR-135a inhibited HOXA10 expression, thereby affecting endometrial receptivity.

A rise in serum progesterone in the late follicular phase is a well described adverse effect of ovarian stimulation for IVF/ICSI. Previous data suggest, that enhanced gonadotropin stimulation causes progesterone elevation and the incidence of premature progesterone elevation can be reduced by declining gonadotropin dosages. This randomized controlled trial (RCT) aimed to achieve a significant reduction of the progesterone level on the day of final oocyte maturation by a daily reduction of 12.5 IU rec-FSH from a follicle size of 14 mm in a GnRH-antagonist protocol. A total of 127 patients had been recruited (Control group (CG): 62 patients; Study group (SG): 65 patients). Due to drop out, data from 108 patients (CG: 55 patients; SG: 53 patients) were included into the analysis. Patients\' basic parameters, gonadotropin (Gn)-starting dose, total Gn-stimulation dosage, the number of retrieved and mature oocytes as well as in the hormonal parameters on the day of trigger (DoT) were not statistically significantly different. However, through stepwise Gn-reduction of 12.5 IU/day in the SG, there was a statistically highly significant difference in the Gn-stimulation dosage on the day of trigger (p < 0.0001) and statistically significant associations for the DoT-P4-levels with the DoT-FSH-levels for both groups (CG: p = 0.001; SG: p = 0.0045). The herein described significant associations between DoT-P4-levels and DoT-FSH-levels confirm the theory that enhanced FSH stimulation is the primary source of progesterone elevation on the day of final oocyte maturation in stimulated IVF/ICSI cycles. Given the pathophysiologic mechanism of progesterone elevation during ovarian stimulation, the use of an increased FSH step-down dosage should be studied in future RCTs, despite the fact that a step-down approach of daily 12.5 IU rec-FSH did not achieve a significantly reduced progesterone level on the DoT. Clinical Trial Registration: clinicaltrials.gov, identifier NCT03356964.

OBJECTIVE: To assess the association between hCG day progesterone levels and subsequent frozen-thawed embryo transfer (FET) cycle outcome in infertile women with and without polycystic ovary syndrome (PCOS).
METHODS: Data of 178 women who underwent FET at a university-based infertility clinic between January 2016 and December 2019 were reviewed. The study group consisted of women who had progesterone elevation (PE) during fresh controlled ovarian stimulation (COS) cycle. A sub-group analysis was also performed in PCOS and non-PCOS patients.
RESULTS: There were no differences in clinical pregnancy (47.7 % vs. 50.7 %, p = 0.729), miscarriage (15.9 % vs. 22.4 %, p = 0.359), and live birth rates (27.3 % vs. 23.9 %, p = 0.652) following FET between women with and without PE in the fresh cycle. The results remained non-significant regarding the clinical pregnancy (46.7 % vs. 53.4 %, p = 0.549), miscarriage (13.3 % vs. 27.6 %, p = 0.133), and live birth rates (26.7 % vs. 19.0 %, p = 0.408) in participants with PCOS (n = 88).
CONCLUSIONS: hCG day progesterone level in the fresh COS cycle does not have a significant impact on the subsequent FET cycle neither in PCOS nor in non-PCOS women.

UNASSIGNED: The advent of ovarian stimulation within an in vitro fertilization (IVF) cycle has resulted in modifying the physiology of stimulated cycles and has helped optimize pregnancy outcomes. In this regard, the importance of progesterone (P4) elevation at time of human chorionic gonadotrophin (hCG) administration within an IVF cycle has been studied over several decades. Our study aimed to evaluate the association of P4 levels at time of hCG trigger with live birth rate (LBR), clinical pregnancy rate (CPR) and miscarriage rate (MR) in fresh IVF or IVF-ICSI cycles.
UNASSIGNED: This was a retrospective cohort study (n=170) involving patients attending the Centre for Reproductive and Genetic Health (CRGH) in London. The study cohort consisted of women undergoing controlled ovarian stimulation using GnRH antagonist or GnRH agonist protocols. Univariate and multiple logistic regression analyses were used to evaluate the association of clinical outcomes. Differences were considered statistically significant if p≤0.05.
UNASSIGNED: As serum progesterone increased, a decrease in LBR was observed. Following multivariate logistical analyses, LBR significantly decreased with P4 thresholds of 4.0 ng/ml (OR 0.42, 95% CI:0.17-1.0) and 4.5 ng/ml (OR 0.35, 95% CI:0.12-0.96).
UNASSIGNED: P4 levels are important in specific groups and the findings were statistically significant with a P4 threshold value between 4.0-4.5 ng/ml. Therefore, it seems logical to selectively measure serum P4 levels for patients who have ovarian dysfunction or an ovulatory cycles and accordingly prepare the individualized management packages for such patients.

Objective: To assess the association between serum ovulation trigger progesterone (P) levels and the outcome of in vitro fertilization cycles. Design Setting: Real world single-center retrospective cohort study. Patient Intervention(s): All fresh cleavage and blastocyst-stage embryo transfers (ETs) performed from January 2012 to December 2016. Main outcome Measure(s): The impact of premature high serum P levels cycles in terms of clinical pregnancy rates (CPRs) and live birth rates (LBRs). Results: 8,034 ETs were performed: 7,597 cleavage-stage transfers and 437 blastocyst transfers. Serum P levels demonstrated to be inversely related to CPR (OR 0.72, p < 0.001) and LBR (OR 0.73, p < 0.001). The progressive decrease of LBR and CPR started when P levels were >1 ng/ml in a good prognosis cleavage ET subgroup, whereas in patients with worse prognosis only for P ≥ 1.75 ng/ml. In the blastocyst ET subgroup, the negative effect of P elevation was reported only if P was >1.75 ng/ml. CPR (OR 0.71 (0.62-0.80), p < 0.001) and LBR (OR 0.73 (0.63-0.84), p < 0.001) in thawed cycles resulted statistically significantly higher than in fresh cycles in the cleavage-stage subgroup. In the blastocyst group, no significant difference resulted between thawed and fresh cycles, independently of P levels [CPR OR 0. 37 (0.49-1.09), p = 0.123; LBR OR 0.71 (0.46-1.10), p = 0.126]. Conclusion: High P levels decrease CPR as well as LBR in both cleavage and blastocyst ET. In the cleavage group, for P levels below 1.75 ng/ml, our data suggest the possibility to wait until day 5 for ET, and if P level is ≥1.75 ng/ml, it should be considered to freeze all embryos and postpone the ET. Clinical Trial Registration: ClinicalTrials.gov, ID: NCT04253470.

Several studies have reported a poor implantation rate for assisted reproduction technology (ART) cycles with elevated progesterone (P4) at the end of the follicular phase. Whether all women with increased P4 on the human chorionic gonadotropin(hCG) trigger day should undergo fresh or frozen embryo transfer (ET) remains to be explored. This study attempted to determine that the P4 level on 2 days before hCG administration and P4 ratio can serve as indicators for fresh ET in normal responders with an elevated P4 level of >1.5 ng/ml on the hCG administration day. This was a retrospective cohort study involving 337 ART cycles with fresh ET for normal responders. Serum P4 levels were measured 2 days prior to hCG day (P4 level I) and on the hCG administration day (P4 level II). The P4 ratio was calculated as follows: P4 ratio = P4 level II / P4 level I. The primary outcome is live birth rate of fresh ET cycles. The ROC curves established that the optimal P4 level I and P4 ratio for pregnancy in ART cycles with high P4 level II were 0.975 ng/ml and 1.62, respectively. Patients with a P4 level I of ≤0.975 ng/ml and P4 ratio of >1.62 were associated with a significantly higher implantation (30.8%, 61/198 vs. 10.3%, 19/184, p < 0.001) and live birth rates (51.6%, 33/64 vs. 15.0%, 9/60, p < 0.001) compared with those with a P4 level I of >0.975 ng/ml and P4 ratio of ≤1.62. A combination of P4 level I and P4 ratio cutoff values of 0.975 ng/ml and 1.62, respectively, had a positive predictive value (PPV) of 82.5% for pregnancy. In conclusion, fresh ET can be an option for women with an early P4 level I under 0.975 ng/ml and a P4 ratio higher than 1.62, especially for those normal responders with an elevated P4 level II >1.5 ng/ml on the hCG administration day. This approach may shorten the time to pregnancy and reduce the cost of ART cycles.