Accelerated endometrial maturation in the luteal phase of cycles utilizing controlled ovarian hyperstimulation: impact of gonadotropin-releasing hormone agonists versus antagonists

Luteal phase support in assisted reproductive technology

Infertility affects one in six couples, with in vitro fertilization (IVF) offering many the chance of conception. Compared to the solitary oocyte produced during the natural menstrual cycle, the supraphysiological ovarian stimulation needed to produce multiple oocytes during IVF results in a dysfunctional luteal phase that can be insufficient to support implantation and maintain pregnancy. Consequently, hormonal supplementation with luteal phase support, principally exogenous progesterone, is used to optimize pregnancy rates; however, luteal phase support remains largely 'black-box' with insufficient clarity regarding the optimal timing, dosing, route and duration of treatment. Herein, we review the evidence on luteal phase support and highlight remaining uncertainties and future research directions. Specifically, we outline the physiological luteal phase, which is regulated by progesterone from the corpus luteum, and evaluate how it is altered by the supraphysiological ovarian stimulation used during IVF. Additionally, we describe the effects of the hormonal triggers used to mature oocytes on the degree of luteal phase support required. We explain the histological transformation of the endometrium during the luteal phase and evaluate markers of endometrial receptivity that attempt to identify the 'window of implantation'. We also cover progesterone receptor signalling, circulating progesterone levels associated with implantation, and the pharmacokinetics of available progesterone formulations to inform the design of luteal phase support regimens.

Effect modification by developmental stage of embryos on the association between late follicular phase progesterone elevation and live birth in fresh transfers

BACKGROUND

Late follicular phase progesterone elevation (LFPE) during ovarian stimulation is associated with reduced live birth rates (LBRs) after cleavage-stage embryo transfer. However, due to better synchronization with a stimulated endometrium, prior studies shown that LFPE had no effect on transferring embryos at blastocyst stage. The study aim to exam whether the developmental stage of embryos and serum progesterone levels on the day of human chorionic gonadotropin (hCG) administration jointly affect the odds of live birth in fresh fresh IVF/intracytoplasmic sperm injection (ICSI) cycles.  METHODS: The single-center retrospective cohort study included a total of 4,471 fresh embryo transfer cycles with 2,342 at cleavage stage versus 2,129 at blastocyst stage. Patients underwent IVF/ICSI with ovarian stimulation in gonadotropin-releasing hormone antagonist protocol. The serum progesterone level was examined both as a continuous variable and as a categorical variable by quartiles. Analysis was performed using the generalized estimating equations framework and multivariate regression models.

RESULTS

LBRs were inversely associated with progesterone as a continuous variable on the day of hCG in both the cleavage-stage (crude OR 0.87, 95%CI 0.73-1.03; adjusted OR 0.80, 95% CI 0.65-0.98) and the blastocyst-stage (crude OR 0.66, 95%CI 0.56-0,78; adjusted OR 0.61, 95%CI 0.50-0.73) groups. The interaction testing was highly significant (P = 0.018) indicating an effect modifying role of stage of embryos transferred on the association of pregesterone values with the LBRs in fresh cycles. A similar pattern for a greater reduction in ORs for live birth in cycles with blastocysts transfer was also observed when progesterone was analyzed by interquartile ranges. The findings remained unchanged in subgroup analysis stratified by types of ovarian response.

CONCLUSIONS

In fresh cycles, detrimental effect of late follicular phase progesterone elevation on live birth was more prominent in blastocyst-stage group compared with that in clevaged-stage group.

Progesterone levels on the human chorionic gonadotropin trigger day affect the pregnancy rates for embryos transferred at different stages of development in both general and selected IVF/ICSI populations

Background

Two meta-analyses have shown that pregnancy and birth rates are significantly higher after blastocyst transfer than after cleaved embryo transfer. Other studies have revealed that a serum progesterone level > 1.5 ng/ml on the trigger day is responsible for premature luteinization and is associated with a low pregnancy rate. The objectives of this retrospective study were to determine whether blastocyst transfer gave higher pregnancy rates than cleaved embryo transfer at day 3 in both the general and selected IVF/ICSI populations, and whether the serum progesterone level influenced the pregnancy rate.

Method

We studied IVF/ICSI cycles with GnRH antagonist - FSH/hMG protocols in a general population (n = 1210) and a selected “top cycle” population (n = 677), after blastocyst transfer on day 5 or cleaved embryo transfer on day 3. The selected couples had to meet the following criteria: female age < 35, first or second cycle, and one or two embryos transferred. We recorded predictive factors for pregnancy and calculated the progesterone to oocyte index (POI), the progesterone:estradiol ratio (P:E2 ratio), and the progesterone to follicle (> 14 mm) index (PFI).

Results

In the general population, the clinical pregnancy rate was significantly higher after blastocyst transfer (33.3%) than after cleaved embryo transfer (25.3%; p <  0.01); the same was true for the birth rate (32.1 and 22.8%, respectively, p <  0.01). The differences between blastocyst and embryo transfer groups were not significant in the selected population (respectively 35.7% vs. 35.8% for the clinical pregnancy rate, and 33.9 and 34.9% for the birth rate). The serum progesterone levels on the eve of the trigger day and on the day itself were significantly lower in the pregnant women (p <  0.01). We found a serum progesterone threshold of 0.9 ng/ml, as also reported by other researchers. The POI and the PFI appear to have predictive value for cleaved embryos transfers.

Conclusions

Blastocyst transfers were associated with higher clinical pregnancy and birth rates than cleaved embryo transfers in a general population but not in a selected population. The serum progesterone levels on the eve of the trigger day and on the day itself predicted the likelihood of pregnancy.

Varying levels of serum estradiol do not alter the timing of the early endometrial secretory transformation

STUDY QUESTION

Do supraphysiologic estradiol (E2) levels in the ranges attained during normal and high response superovulation cycles modify the onset of endometrial secretory transformation?

SUMMARY ANSWER

Highly supraphysiologic levels of E2 do not alter the ability of physiologic levels of progesterone (P4) to induce secretory transformation.

WHAT IS KNOWN ALREADY

Previous studies have demonstrated that premature P4 elevations during IVF cycles are associated with a decrement in clinical pregnancy rates after fresh embryo transfer due to shifts in the window of implantation (WOI). However, alterations in the onset of secretory transformation may not apply uniformly to all patients. High responders with supraphysiologic E2 levels accompanied by similar subtle increases in P4 have not been shown to have decreased sustained implantation rates. This prospective investigation in which whole-genome transcriptomic and methylomic analysis of the endometrium is performed for individual patients under a range of E2 concentrations brings clarity to a long-debated issue.

STUDY DESIGN, SIZE, DURATION

A randomized, prospective and paired trial was conducted in which 10 participants were enrolled and randomized to the order in which they completed three distinct uterine stimulation cycles, each at a specific E2 concentration: physiologic (∼180 pg/ml), moderately supraphysiologic (600-800 pg/ml) or supraphysiologic (2000 pg/ml). Target E2 ranges were selected to mimic those seen in natural, controlled ovarian stimulation and IVF cycles. E2 valerate was administered in order to maintain stable E2 levels for 12 days followed by intramuscular P4 in oil 10 mg/day for two doses, after which an endometrial biopsy was performed. A total of 30 endometrial biopsies were included in a whole-genome transcriptomic and methylomic analysis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Healthy volunteers without a history of infertility were included in this study at a single large infertility center. DNA was isolated from the endometrial biopsy specimens and bisulfite sequencing was performed to construct a methylation array. Differential methylation analysis was conducted based on differences in M-values of individuals across treatment groups for each probe as well as carrying out t-tests. RNA was isolated for RNA-Seq analysis and gene expression values were compared using DESeq2. All analyses were performed in a pairwise fashion to compare among the three stimulation cycles within individuals and secondarily to compare all participants in each of the cycles.

MAIN RESULTS AND THE ROLE OF CHANCE

The mean peak E2 and P4 levels were 275 pg/ml and 4.17 ng/ml in the physiologic group, 910 pg/ml and 2.69 ng/ml in the moderate group was, and 2043 pg/ml and 2.64 ng/ml in the supraphysiologic group, respectively. Principal component analysis of 834 913 CpG sites was performed on M-values of individuals within the low, moderate and supraphysiologic conditions in a paired approach. There were no differences in genome-wide methylation within participants across E2 groups. A paired analysis revealed that gene expression profiles did not differ within the same individual at each of the three E2 levels. No significant alterations in gene expression as related to endometrial physiology were identified between the low, moderate and supraphysiologic groups in an inter-participant analysis.

LIMITATIONS, REASONS FOR CAUTION

Although each participant completed a physiologic cycle in which E2 levels were maintained in a range that would simulate a natural cycle, our findings are limited by lack of an unmedicated control to assess if there was a potential effect from E2V. Additionally, our results were obtained in fertile individuals, who may have a different endometrial response compared to an infertile population. Despite the whole genomic endometrial assessment and rigorous, paired study design, the sample size was limited.

WIDER IMPLICATIONS OF THE FINDINGS

Given that the endometrial response to P4 is unaffected by E2 levels in the supraphysiologic range, diminutions in implantation seen in stimulated cycles may result from embryonic-endometrial dyssynchrony following early P4 elevations or slowly blastulating embryos, which occur independently of the magnitude of the E2 rise.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Foundation for Embryonic Competence, Basking Ridge, NJ, USA. Dr E.S. reports consultancy work for The Foundation for Embryonic Competence, Basking Ridge, NJ, USA. The other authors declare no conflict of interests related to this topic.

TRIAL REGISTRATION NUMBER

NCT02458404.

Organoids of the female reproductive tract

Healthy functioning of the female reproductive tract (FRT) depends on balanced and dynamic regulation by hormones during the menstrual cycle, pregnancy and childbirth. The mucosal epithelial lining of different regions of the FRT-ovaries, fallopian tubes, uterus, cervix and vagina-facilitates the selective transport of gametes and successful transfer of the zygote to the uterus where it implants and pregnancy takes place. It also prevents pathogen entry. Recent developments in three-dimensional (3D) organoid systems from the FRT now provide crucial experimental models that recapitulate the cellular heterogeneity and physiological, anatomical and functional properties of the organ in vitro. In this review, we summarise the state of the art on organoids generated from different regions of the FRT. We discuss the potential applications of these powerful in vitro models to study normal physiology, fertility, infections, diseases, drug discovery and personalised medicine.

Shortcomings of an unphysiological triggering of oocyte maturation using human chorionic gonadotropin

Final maturation of follicles has, in connection with ovarian stimulation and infertility treatment, traditionally been achieved by the administration of a human chorionic gonadotropin (hCG) bolus trigger of 5,000 to 10,000 IU. This trigger serves two purposes: induce oocyte maturation; and serve as luteal phase support owing to its long half-life. It now appears that the hCG bolus trigger is unable to support both these two purposes optimally. In particular, after an hCG trigger, the early luteal phase is hormonally abnormal and different from conditions observed in the natural menstrual cycle: the timing of the initiation of hCG and progesterone rise is much faster after an hCG trigger than in a natural menstrual cycle; the maximal concentrations of hCG and progesterone considerably exceed those naturally observed; and the timing of the peak progesterone concentration after an hCG trigger is advanced several days compared with the natural cycle. Furthermore, the hCG trigger without any follicle-stimulating hormone activity may induce oocyte maturation less efficiently than the combined luteinizing hormone and follicle-stimulating hormone surge normally seen. Collectively, the endometrium is likely to be advanced after an hCG trigger, and the implantation potential is probably not optimal. The precise effect on pregnancy rates after the different progressions of hCG and progesterone concentrations during the early luteal phase has not yet been determined, but more individualized methods using more physiological approaches are likely to improve reproductive outcomes.

Frozen IVF Cycles to Circumvent the Hormonal Storm on Endometrium

Controlled ovarian hyperstimulation (COH) determines an anticipation of endometrial maturation and a premature occurrence of the implantation window, as shown by histological, histochemical, and molecular studies and indirectly by clinical trials. There is growing agreement that in patients hyper-responding to COH and in those undergoing transfer at the blastocyst stage, deferring the transfer in a subsequent frozen cycle could increase pregnancy outcomes. For blastocysts, implantation after a fresh transfer may be limited as the implantation window is already closed while, in hyper-responders to COH, the anticipation magnitude could be more marked thus hampering implantation also for cleavage-stage embryos. Research should focus in depth on pregnancy outcomes and on the most suitable modality to prepare the endometrium for frozen transfers.

Early Progesterone Change Associated With Pregnancy Outcome After Fresh Embryo Transfer in Assisted Reproduction Technology Cycles With Progesterone Level of >1.5 ng/ml on Human Chorionic Gonadotropin Trigger Day

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.

Novel uterine lavage system for recovery of human embryos fertilized and matured in vivo

Purpose: In this paper we describe a novel uterine lavage system for the recovery of in vivo preimplantation embryos. Currently, no other method exists to retrieve preimplantation embryos except for in vitro fertilization (IVF).

Methods: A single center, prospective feasibility study was conducted to test a novel uterine lavage system for the recovery of in vivo preimplantation embryos in egg donors and patients seeking pregnancy. Subjects were placed on controlled ovarian hyperstimulation followed by intrauterine insemination (IUI) and uterine lavage performed approximately 4–6 days after IUI. Subjects were followed up for 30 days after the procedure to monitor for safety events.

Results: A total of 134 uterine lavage cycles were performed on 81 subjects (average: 1.7 cycles/subject). Ova (oocytes or embryos) were collected in 53% (71/134) of the cycles with steady improvement of recovery efficiency over the course of the study, and embryos collected in 42% (56/134) of cycles. Embryos of many stages were collected, but 71% (96/136) of embryos collected were blastocyst stage embryos which are at the most advanced stage of embryogenesis. Embryos recovered were of good quality based on blastocyst gradings in which 74% (70/95, 1 blastocyst not graded) of the blastocysts were good quality as determined by the Gardner Scale of Morphology. The procedure was well tolerated with minor side effects. In 8% of cycles a positive hCG was observed after the lavage indicating some embryos were not recovered by the lavage system.

Conclusion: Through this work the system has been shown to recover embryos from the uterus in a safe and effective manner, thus opening the possibility that uterine lavage may serve as an alternative to IVF where patient indications allow.

[Natural cycle for frozen-thawed embryo transfer: Spontaneous ovulation or triggering by HCG]

OBJECTIVE

To compare frozen-thawed embryo transfer (FET) outcomes in natural cycles according to ovulation induction: spontaneous versus recombinant human chorionic gonadotrophin (r-hCG) triggering.

METHODS

This retrospective study included all patients monitored for natural cycle FET during one year. When serial monitoring were performed until spontaneous LH rise, patients were included in group A (n=38) whereas those receiving r-hCG for ovulation triggering formed group B (n=43). All embryos had been cryopreserved by a vitrification method following a previous IVF cycle. No luteal phase support had been given. We compared outcomes between the 2 groups.

RESULTS

After checking groups comparability, we didn't find significant difference for the implantation rate, clinical pregnancy rate and live birth (31% vs 45%, 32% vs 51% et 21% vs 32%, respectively for group A and B). The number of monitoring was significantly lower in group B (1,9±0,8 versus 2,5±1, P=0,006).

DISCUSSION

Although no consensus has been yet established, natural cycle seems indicated for normo-ovulating patients but the question of ovulation induction is still debated. In our study, triggering ovulation by r-hCG, respecting strict criteria, seems provide good results while reducing both protocol's constraints and cost.

Increased Uterine NK cell numbers and perforin expression during the implantation phase in IVF Cycles with GnRH Antagonist Protocol

GnRH antagonist negatively affects endometrial receptivity in in vitro fertilization (IVF) cycles, however, its underlying mechanism remains unclear. To explore its target molecules, we studied endometria in the window phase of fixed GnRH antagonist, low-dose flexible GnRH antagonist, GnRH agonist long protocol, and untreated control groups. There were 384 differentially expressed genes (DEGs) in the fixed antagonist group with greater than twofold expression change compared with the control group and 197 DEGs between the fixed antagonist and agonist groups, the majority of which were associated with the natural killer (NK) cell-mediated cytotoxicity pathway. We then analysed the PRF1 and FASLG protein levels. The perforin level were significantly higher in both the antagonist groups than in other two groups, and was higher in the fixed antagonist group. Similarly, the uNK cell numbers were higher in the antagonist groups, and the highest uNK cell number occurred in the fixed group (p < 0.05). No significant differences existed in the Fas ligand levels and apoptosis rates among the three treatment groups, but were higher in the treatment groups than the control group. Together, these data indicate that GnRH antagonist may increase the uNK cell numbers and perforin expression, and this effect may be dose-dependent.

The Impact of Progesterone Level on Day Of hCG Injection in IVF Cycles on Clinical Pregnancy Rate

Background:

Premature progesterone rise (PPR) has long been implicated as contributing to implantation failure. Despite the use of gonadotropin-releasing hormone (GnRH) analogues, subtle increases in serum progesterone (P₄) levels beyond a threshold progesterone concentration were observed on the day of trigger in controlled ovarian hyperstimulation cycles.

Aims:

The purpose of the study was to evaluate the incidence of PPR on the day of trigger in conventional IVF/ICSI cycles and its impact on clinical pregnancy rate.

Settings and Design:

A total of 235 patients undergoing conventional IVF/IVF–ICSI by fresh embryo transfer cycles from January 2016 to December 2016 at the infertility unit of a tertiary care hospital were prospectively analyzed.

Material and Methods:

Patients included in the study were subjected to GnRH agonist long/antagonist protocol. Ovulation induction was given with rFSH and/or HMG in both the protocols. The cutoff for defining PPR was P₄≥ 1.5 ng/ml, and an analysis of the role of P₄on clinical pregnancy rate was performed. Statistical analysis was performed with the Statistical Package for the Social Sciences trial version 23.0 software for Windows and Primer software.

Results and Conclusion:

The overall clinical pregnancy rate per embryo transfer was 30.6%. The clinical pregnancy rate in the patients with P₄ <1.5 ng/ml was significantly higher than those with elevated levels, P₄≥ 1.5 ng/ml (33.3% vs. 12.9%; P = 0.037). Premature progesterone elevation in ART cycles is possibly associated with lower clinical pregnancy rates.

Sleep in women undergoing in vitro fertilization: a pilot study

OBJECTIVE

Sleep disturbances are thought to be frequent in women undergoing IVF despite minimal research of this hypothesis. Our goal was to longitudinally assess sleep duration and disturbances in women undergoing IVF and assess impact of habitual sleep duration on oocytes retrieved, an important outcome in IVF.

METHODS

Actigraphy and questionnaire batteries containing sleep and psychometric instruments were performed prior to and throughout 24 IVF cycles.

RESULTS

TST <7 h was present in 46%, 57%, 69%, and 42% of baseline, stimulation, post-oocyte retrieval, and post-embryo transfer recordings. ESS >10 was noted in 24%, 33%, and 36% of cycles during baseline, stimulation, and post-embryo transfer. PSQI >5 was noted in 57%, 43%, and 29% of cycles during baseline, stimulation, and post-embryo transfer. TST (F = 2.95, p = 0.04) and ESS (F = 4.36, p = 0.02) were the only sleep metrics in which a significant main effect of time was found by mixed models analysis. The final linear regression model chosen by stepwise selection to best explain the variability in oocytes retrieved included anti-mullerian hormone, day three follicle stimulating hormone, and baseline TST and explained 40% of the variance in oocytes retrieved (adjusted R² = 0.40, p = 0.03). Although not statistically significant, a trend towards a linear association between baseline TST and oocytes retrieved was seen with an increase of oocytes retrieved by 1.5 for every hour increase in TST (p = 0.09).

CONCLUSIONS

This is the first study to describe, with subjective and objective measures, sleep disturbances present throughout the IVF cycle. Importantly, a trend towards a linear relationship between TST and oocytes retrieved was found in this pilot study. Sleep may be a modifiable target to improve outcomes in women undergoing IVF and further investigations are needed.

Non-invasive prediction of implantation window in controlled hyperstimulation cycles: Can the time from the menstrual day at embryo transfer to expected menstrual cycle give a clue?

Objective:

The aim of this study was to assess whether the time from the menstrual day at embryo transfer to expected menstrual cycle (TETEMC) is associated with the implantation in women with regular cycles or not.

Materials and Methods:

Forty women with successful implantation and forty women without implantation with regular cycles were randomly selected from prospectively collected database of assisted reproductive technology clinic of Zeynep Kamil Women And Children’s Health Training and Research Hospital. TETEMC was calculated for each case to assess relationship with the successful implantation.

Results:

Comparison of groups revealed significant differences with regard to TETEMC and the menstrual period (p<0.05).

In ROC analyses both the TETEMC (AUC=0.824, p<0.001) and the menstrual period (AUC=0.797, p<0.001) were significant predictors for clinical pregnancy. Cut off value for the menstrual period was found to be 27.5 days with 82.6% sensitivity and 65% specificity. Cut off value for TETEMC was 11.5 days with 75% sensitivity and 63.2% specificity.

Conclusion:

Longer menstrual cycle and the TETEMC seem to be associated with the implantation failure.

Intrauterine human chorionic gonadotropin infusion in oocyte donors promotes endometrial synchrony and induction of early decidual markers for stromal survival: a randomized clinical trial

STUDY QUESTION

Does a single intrauterine infusion of human chorionic gonadotropin (hCG) at the time corresponding to a Day 3 embryo transfer in oocyte donors induce favorable molecular changes in the endometrium for embryo implantation?

SUMMARY ANSWER

Intrauterine hCG was associated with endometrial synchronization between endometrial glands and stroma following ovarian stimulation and the induction of early decidual markers associated with stromal cell survival.

WHAT IS KNOWN ALREADY

The clinical potential for increasing IVF success rates using an intrauterine hCG infusion prior to embryo transfer remains unclear based on previously reported positive and non-significant findings. However, infusion of CG in the non-human primate increases the expression of pro-survival early decidual markers important for endometrial receptivity, including α-smooth muscle actin (α-SMA) and NOTCH1.

STUDY DESIGN, SIZE, DURATION

Oocyte donors (n=15) were randomly assigned to receive an intrauterine infusion of 500 IU hCG (n=7) or embryo culture media vehicle (n=8) 3 days following oocyte retrieval during their donor stimulation cycle. Endometrial biopsies were performed 2 days later, followed by either RNA isolation or tissue fixation in formalin and paraffin embedding.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Reverse transcription of total RNA from endometrial biopsies generated cDNA, which was used for analysis in the endometrial receptivity array (ERA; n = 5/group) or quantitative RT-PCR to determine relative expression of ESR1, PGR, C3 and NOTCH1. Tissue sections were stained with hematoxylin and eosin followed by blinded staging analysis for dating of endometrial glands and stroma. Immunostaining for ESR1, PGR, α-SMA, C3 and NOTCH1 was performed to determine their tissue localization.

MAIN RESULTS AND THE ROLE OF CHANCE

Intrauterine hCG infusion was associated with endometrial synchrony and reprograming of stromal development following ovarian stimulation. ESR1 and PGR were significantly elevated in the endometrium of hCG-treated patients, consistent with earlier staging. The ERA did not predict an overall positive impact of intrauterine hCG on endometrial receptivity. However, ACTA2, encoding α-SMA was significantly increased in response to intrauterine hCG. Similar to the hCG-treated non-human primate, sub-epithelial and peri-vascular α-SMA expression was induced in women following hCG infusion. Other known targets of hCG in the baboon were also found to be increased, including C3 and NOTCH1, which have known roles in endometrial receptivity.

LIMITATIONS, REASONS FOR CAUTION

This study differs from our previous work in the hCG-treated non-human primate along with clinical studies in infertile patients. Specifically, we performed a single intrauterine infusion in oocyte donors instead of either continuous hCG via an osmotic mini-pump in the baboon or infusion followed by blastocyst-derived hCG in infertile women undergoing embryo transfer. Therefore, the full impact of intrauterine hCG in promoting endometrial receptivity may not have been evident.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings suggest a potential clinical benefit for intrauterine hCG prior to embryo transfer on Day 3 in counteracting endometrial dyssynchrony from ovarian stimulation and promoting expression of markers important for stromal survival. Finally, there were no obvious negative effects of intrauterine hCG treatment.

STUDY FUNDING/COMPETING INTERESTS

Funding for this work was provided by NICHD R01 HD042280 (A.T.F.) and NICHD F30 HD082951 (M.R.S.). C.S. and P.D.-G are co-inventors of the patented ERA, which is owned by IGENOMIX SL and was used in this study, and C.S. is a shareholder in IGENOMIX SL. M.R.-A. is employed by IGENOMIX SL. No other authors have any conflicts of interest to report.

TRIAL REGISTRATION NUMBER

This study was registered with ClinicalTrials.gov (NCT01786252).

TRIAL REGISTRATION DATE

5 February 2013.

DATE OF FIRST PATIENT'S ENROLLMENT

10 May 2013.

Progesterone change in the late follicular phase affects pregnancy rates both agonist and antagonist protocols in normoresponders: a case-controlled study in ICSI cycles

OBJECTIVE

The aim of the presented study is to investigate the impact of progesterone change in the late follicular phase on the pregnancy rates of both agonist and antagonist protocols in normoresponders.

STUDY DESIGN

A total of 201 normoresponder patients, who underwent embryo transfer were consecutively selected. 118 patients were stimulated using a long luteal GnRH agonist protocol and 83 using a flexible antagonist protocol. The level of change in late follicular phase progesterone was calculated according to the progesterone levels on the hCG day and pre-hCG day (1 or 2 days prior to hCG day) measurement.

RESULTS

Clinical pregnancy rates were comparable between long luteal and antagonist group (35.6 and 41%, respectively). The incidence of progesterone elevation on the hCG day was 11% in long luteal and 18% in antagonist group (p = 0.16). In pregnant cycles, p levels both on the hCG day and pre-hCG day measurement were significantly higher in antagonist than agonist cycles (p = 0.029, p = 0.038, respectively). The change of p level was statistically significant in non-pregnant cycles both for the agonist (-0.17 ± 0.07; 95% CI: -0.29 to -0.37) and antagonist groups (-0.18 ± 0.07; 95%CI: -0.31 to -0.04).

CONCLUSIONS

Late follicular phase progesterone levels were stable during the cycles of pregnant patients irrespective of the protocols and were shown to be higher in pregnant patients in antagonist cycles when compared to agonist cycles.

Developmentally delayed cleavage-stage embryos maintain comparable implantation rates in frozen embryo transfers

PURPOSE

In fresh IVF cycles, embryos reaching the eight-cell stage on day 3 of development are thought to have a higher chance of implantation than those reaching this stage on day 4. To determine whether this difference persists after cryopreservation, we compared pregnancy and implantation rates between frozen embryo transfer (FET) cycles using delayed cleavage-stage embryos (cryopreserved day 4) and normal cleavage-stage embryos (cryopreserved day 3).

METHODS

Participants underwent FET between 2008 and 2012 using embryos cryopreserved on either day 3 (n = 76) or day 4 (n = 48), depending on the length of time needed to achieve the eight-cell stage. All embryos, regardless of day of cryopreservation, were thawed and transferred on the 4th day of vaginal progesterone following endometrial preparation with oral estradiol. Chi-square and Mann-Whitney U tests were used to compare patient demographics and cycle outcomes.

RESULTS

More women in the day 4 group had diminished ovarian reserve (44 vs 16 %, p = 0.003). Pregnancy outcomes in preceding fresh cycles were not different between the two groups. Pregnancy, implantation, and live birth rates following FET did not differ between the day 3 and day 4 groups.

CONCLUSIONS

This is the first study to address outcomes using day 3 versus day 4 cryopreserved embryos. Despite a higher prevalence of diminished ovarian reserve (DOR) in the day 4 group, delayed cleavage-stage embryos utilized in FET cycles performed as well as embryos growing at the normal rate, suggesting delayed embryo development does not affect embryo implantation as long as endometrial synchrony is maintained.

Bu Shen Huo Xue decoction restores endometrial leukemia-inhibitory factor but not Angiopoietin-2 expression, and improves uterine receptivity in the controlled ovarian stimulation rat model

Leukemia-inhibitory factor (LIF) and Angiopoietin-2 (Ang-2) are important factors in fertility. In the present study, it was investigated whether Bu Shen Huo Xue Decoction (BSHXD) prevents controlled ovarian hyperstimulation (COH) treatment-induced changes in endometrial LIF and Ang-2 expression and whether it has an effect on the number of implantation sites and live births in rats. Uteri were collected on day (D) 3, 4 and 5 of pregnancy, and LIF and Ang-2 protein and mRNA expression were detected using western blot analysis and quantitative polymerase chain reaction. On pregnancy D10, the average number of implantation sites was observed. The number of live births from each group was recorded. The results indicated that BSHXD treatment markedly increased the number of live births by restoring endometrial LIF expression and the implantation capacity in the COH rat model. In addition, no association was identified between LIF and Ang-2 expression. Therefore, this suggests that BSHXD may be useful for female reproduction.

Premature formation of nucleolar channel systems indicates advanced endometrial maturation following controlled ovarian hyperstimulation

STUDY QUESTION

Is there a shift in the timing of nucleolar channel system (NCS) formation following controlled ovarian hyperstimulation (COH)?

SUMMARY ANSWER

NCSs appear prematurely following COH compared with natural cycles.

WHAT IS KNOWN ALREADY

During natural cycles, NCSs of endometrial epithelial cell (EEC) nuclei are exclusively present during the window of implantation and are uniformly distributed throughout the upper endometrial cavity.

STUDY DESIGN, SIZE, DURATION

Prospective two-cohort study. Cohorts I and II each consisted of seven volunteers for the duration of three menstrual study cycles that were separated by at least one wash-out or rest cycle, between December 2008 and May 2012.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were recruited from a pool of healthy oocyte donors. Consecutive endometrial biopsies were obtained during the same luteal phase on cycle days (CD) 16, 20 and 26 for Cohort I, and on CD14, 22 and 24 for Cohort II, following random assignment to a natural cycle group, a COH cycle group (using a GnRH antagonist), or a COH cycle group receiving luteal phase hormonal supplementation (COH + S). The day of oocyte retrieval was designated CD14 in COH cycles and the day of the LH surge was designated CD13 in natural cycles. Prevalence of NCSs in the nuclei of EECs was quantified using indirect immunofluorescence with an antibody directed against a subset of related nuclear pore complex proteins that are major constituents of NCSs. Progesterone and estradiol levels were measured on the day of each endometrial biopsy.

MAIN RESULTS AND THE ROLE OF CHANCE

The natural cycle group exhibited peak NCS prevalence on CD20 [53.3%; interquartile range (IQR) 28.5-55.8], which rapidly declined on CD22 (11.8%; IQR 6.3-17.6), CD24 (2.5%; IQR 0.0-9.2) and CD26 (0.3%; IQR 0.0-3.5), and no NCSs on CD14 and 16 defining a short NCS window around CD20. In contrast, in COH and COH + S cycles, NCS prevalence was high already on CD16 (40.4%; IQR 22.6-53.4 and 35.6%; IQR 26.4-44.5, respectively; P = 0.001 compared with CD16 of the natural cycle group, Mann-Whitney), whereas no significant difference in NCS prevalence was detected on any of the other five CDs between the three groups (P > 0.05).

LIMITATIONS, REASONS FOR CAUTION

The cohort size was small (n = 7) but was offset by the all-or-none presence of NCSs on CD16 in natural versus COH and COH + S cycles and the fact that each subject served as her own control.

WIDER IMPLICATIONS OF THE FINDINGS

Premature appearance of NCSs and hence maturation of the endometrium following COH is consistent with previous studies based on histological dating but contradicts studies based on mRNA expression profiling, which reported a lag in endometrial maturation. However, this is the first study of this kind that is based on consecutive endometrial biopsies within the same cycle and that reports such clear-cut differences: no versus robust NCS presence on CD16. Our observation of advanced endometrial maturation following COH may contribute to the reduced implantation rates seen in fresh compared with frozen and donor IVF-embryo transfer cycles. Therefore, the NCS window could serve as a sensitive guide for timing of embryo transfer in frozen and donor cycles.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by the March of Dimes Birth Defects foundation (1-FY09-363 to U.T.M.); Ferring Pharmaceuticals, Parsippany, NJ; East Coast Fertility, Plainview, NY and the CMBG Training Program (T32 GM007491 to M.J.S.). We report no competing interests.

The coregulator, repressor of estrogen receptor activity (REA), is a crucial regulator of the timing and magnitude of uterine decidualization

Successful implantation and maintenance of pregnancy require the transformation of uterine endometrial stromal cells into distinct decidualized cells. Although estrogen and progesterone (P4) receptors are known to be essential for decidualization, the roles of steroid receptor coregulators in this process remain largely unknown. In this study, we have established a key role for the coregulator, repressor of estrogen receptor activity (REA), in the decidualization of human endometrial stromal cells (hESCs) in vitro and of the mouse uterus in vivo. Our studies revealed that the level of REA normally decreases to half as hESC decidualization proceeds and that uterine reduction of REA in transgenic heterozygous knockout mice or small interfering RNA knockdown of REA in hESC temporally accelerated and strongly enhanced the differentiation process, as indicated by changes in cell morphology and increased expression of biomarkers of decidualization, including P4 receptor. Findings in hESC cultured in vitro with estradiol, P4, and 8-bromo-cAMP over a 10-day period mirrored observations of enhanced decidualization response in transgenic mice with heterozygous deletion of REA. Importantly, gene expression and immunohistochemical analyses revealed changes in multiple components of the Janus kinase/signal transducer and activator of transcription pathway, including marked up-regulation of signal transducer and activator of transcription 3 and IL-11, master regulators of decidualization, and the down-regulation of several suppressor of cytokine signaling family members, upon reduction of REA. The findings highlight that REA physiologically restrains endometrial stromal cell decidualization, controlling the timing and magnitude of decidualization to enable proper coordination of uterine differentiation with concurrent embryo development that is essential for implantation and optimal fertility.

The duration of pre-ovulatory serum progesterone elevation before hCG administration affects the outcome of IVF/ICSI cycles

STUDY QUESTION

During controlled ovarian stimulation (COS), does the duration of premature serum progesterone (P) elevation before administration of hCG affect the outcomes of IVF/ICSI embryo transfer (-ET) cycles?

SUMMARY ANSWER

The duration of the premature serum P elevation is inversely related to the clinical pregnancy rate of IVF/ICSI-ET cycles.

WHAT IS KNOWN AND WHAT THIS PAPER ADDS

The majority of the previous studies only considered a single serum P measurement made on the day of hCG administration and the results of attempts to relate this to IVF/ICSI-ET outcomes were controversial. However, the effect of the duration of premature serum P elevation before the hCG administration on the outcomes of IVF/ICSI-ET cycles has not been studied well. Here we demonstrate that the duration of premature serum P elevation has a more significant inverse correlation than the absolute serum P concentration on the day of hCG administration with IVF/ICSI-ET outcomes.

DESIGN

It is a retrospective, single-centre cohort study. A total of 1784 IVF and/or ICSI-ET cycles were included from October 2005 to June 2011.

PARTICIPANTS AND SETTING

A total of 1784 patients underwent their IVF and/or ICSI-ET cycles in a university hospital IVF unit. The inclusion criteria include (i) age between 20 and 42 years and (ii) eligible indications for COS before IVF/ICSI.

MAIN RESULTS AND THE ROLE OF CHANCE

The duration of premature serum P elevation to >1 ng/ml is significantly inversely associated with the probability of clinical pregnancy (odds ratio = 0.773, 95% confidence interval: 0.660-0.891, P < 0.001), after adjustment for possible confounders with multivariate logistic regression analysis. However, the significance of inverse correlation between the absolute serum P concentration on the day of hCG administration with clinical pregnancy rate decreased after adjustment.

BIAS, CONFOUNDING AND OTHER REASONS FOR CAUTION

The cutoff value we chose to define premature serum P elevation (P > 1.0 ng/ml) might not be able to be applied to different immunoassay kits and study population. The retrospective nature of this study inevitably might be influenced by some selection bias.

GENERALIZABILITY TO OTHER POPULATIONS

Older patients (>42 years) are excluded from our study.

[Views of each member of an Assisted Reproductive Technologies centre on the embryo transfer procedure]

The embryo transfer (ET) is probably the key step of Assisted Reproductive Technologies (ART), end point of the collaboration of a multidisciplinary clinical team and an infertile couple. Thus, a perfect knowledge of available data regarding ET is required to optimize the results of ART. Indeed, numerous published studies demonstrate the impact of defined parameters onto the effectiveness of ET procedure. The aim of this study is to provide views of physicians dealing with ART, i.e. endocrinologist, ultrasound scan specialist, surgeon and biologist to put in perspective questions and answers about ET.

Cessation of gonadotropin-releasing hormone antagonist on triggering day: an alternative method for flexible multiple-dose protocol

This study was performed to analyze retrospectively outcomes of stimulated in vitro fertilization (IVF) cycles where the gonadotropin-releasing hormone (GnRH) antagonist was omitted on ovulation triggering day. A total of 92 consecutive IVF cycles were included in 65 women who are undergoing ovarian stimulation with recombinant FSH. A GnRH antagonist, cetrorelix 0.25 mg/day, was started when leading follicle reached 14 mm in diameter until the day of hCG administration (Group A, 66 cycles) or until the day before hCG administration (Group B, 26 cycles). The duration of ovarian stimulation, total dose of gonadotropins, serum estradiol levels on hCG administration day, and the number of oocytes retrieved were not significantly different between the two groups. The total dose of GnRH antagonist was significantly lower in Group B compared to Group A (2.7+/-0.8 vs. 3.2+/-0.9 ampoules). There was no premature luteinization in the subjects. The proportion of mature oocytes (71.4% vs. 61.7%) and fertilization rate of mature (86.3+/-19.7% vs. 71.8+/-31.7%) was significantly higher in Group B. There were no significant differences in embryo quality and clinical pregnancy rates. Our results suggest that cessation of the GnRH antagonist on the day of hCG administration during a flexible multiple-dose protocol could reduce the total dose of GnRH antagonist without compromising IVF results.

Early pregnancy loss rates were different among singleton gestations conceived by ICSI using GnRH agonist and antagonist

This study compared early pregnancy losses (termination of pregnancy before 12 weeks of gestation, EPL) among conceptions achieved by ICSI according to the type of GnRH analogue for ovarian stimulation. Only singleton gestations (2,184) and fresh embryo transfers were included. GnRH agonist was used in 848 gestations out of 2,184 and GnRH antagonist was used in the remaining 1,336 gestations. EPL was found to be significantly higher in GnRH antagonist gestations compared to GnRH agonist (27.2% vs 18.9%). This significant difference persisted when gestations were segregated according to maternal age, especially among women younger than 35 years old. Therefore our results suggest that gestations conceived by ovarian stimulation including GnRH antagonists may have higher probability of having EPL.

Embryo cryopreservation rescues cycles with premature luteinization

OBJECTIVE

To determine whether embryo cryopreservation in cycles with elevated preovulatory P followed by thaw, extended culture, and transfer results in greater ongoing pregnancy rates than fresh blastocyst transfer.

DESIGN

Retrospective matched cohort study.

SETTING

Private fertility center.

PATIENT(S)

The study group consisted of 118 consecutive thaws of bipronucleate (2PN) oocytes derived from autologous cycles with elevated preovulatory P, resulting in 95 blastocyst transfers. The control group was selected by matching on the number of 2PN oocytes and patient age and consisted of 118 fresh cycles with elevated preovulatory P, including 108 fresh autologous blastocyst transfers. All patients were <41 years old at the time of stimulation.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Implantation and ongoing pregnancy rates.

RESULT(S)

The study group had significantly fewer blastocysts per 2PN oocyte than the control group (19.7% vs. 36.8%, respectively) and a significantly greater cancellation rate (19.5% vs. 8.5%, respectively). However, the ongoing pregnancy rate per cycle was significantly higher in the study group than in the control group (56.8% vs. 32.2%, respectively), resulting from greater rates of implantation (56.8% vs. 26.9%, respectively) and of ongoing pregnancy per transfer (70.5% vs. 35.2%, respectively).

CONCLUSION(S)

In cycles with elevated preovulatory P, the probabilities of implantation and ongoing pregnancy are increased if all 2PN oocytes are cryopreserved and subsequently thawed and cultured to the blastocyst stage before transfer.

Co-transfer of embryos derived from cryopreserved and fresh natural cycle oocytes: a pilot study

Italian legislation regarding reproductive medicine prohibits embryo storage while allowing cryopreservation of supernumerary oocytes. This study evaluated the effect of fresh oocytes obtained from natural unstimulated cycles on the clinical success rates derived from the use of frozen-thawed (FR-TH) oocytes obtained following ovarian stimulation. For 36 women, intracytoplasmic sperm injection was performed on FR-TH oocytes supplemented by a fresh oocyte, if available, derived from a natural cycle in which gonadotrophin-releasing hormone-antagonist was used for premature LH surge control. The retrieval rate of fresh oocytes was 61.1% and survival rate of FR-TH oocytes was 43.6%. The fertilization rate of fresh and FR-TH oocytes was 70% and 52.5%, respectively. Fifty embryos were transferred, 14 of them developed from fresh oocytes and 36 from FR-TH oocytes. Six pregnancies occurred in 10 cycles in which the embryos developed from fresh and FR-TH oocytes (pregnancy rate 60.0%) and two in 12 patients in whom the embryos were obtained from only FR-TH oocytes (pregnancy rate 16.7%) (P < 0.05). In summary, the data demonstrate that the transfer of embryos derived from oocytes cryopreserved following a previous ovarian stimulation and an embryo developed from a fresh one retrieved in natural cycle ensures an excellent clinical outcome.

Mild stimulation with clomiphene citrate in combination with recombinant follicle-stimulating hormone and gonadotropin-releasing hormone antagonist and its influence on serum estradiol level and pregnancy rate

Aim:  The mild ovarian stimulation protocol for in vitro fertilization (IVF) is carried out to minimize adverse side-effects as well as cost. While performing mild ovarian stimulation with a gonadotropin-releasing hormone (GnRH) antagonist, the pregnancy rate was examined in cases that exhibited a serum estradiol (E2) drop down. Methods:  In this study, 174 patients who requested mild ovarian stimulation for IVF began clomiphene citrate on day 3 and recombinant follicle-stimulating hormone (FSH) on day 5 of their menstrual cycles. A GnRH antagonist was administered when the dominant follicle reached a diameter of 14 mm. Serum luteinizing hormone and estradiol were measured at the time of GnRH antagonist administration and at the time of human chorionic gonadotropin (hCG) injection. Pregnancy rates and implantation rates were compared between 24 cycles in which the E2 level fell at the time of hCG injection and 150 cycles in which it did not fall. Results:  The pregnancy rate in the cases in which the E2 level fell (25% decrease) at the time of hCG injection was significantly lower than it was in the cases in which it did not fall (16.7 vs 41.0%). The implantation rate for the cases in which the E2 level fell was also lower than that of the control group (7.0 vs 31.0%). There was no significant difference in the number of good-quality embryos between the two groups. Conclusion:  When performing the mild ovarian stimulation protocol, serum E2 should be followed. It is prudent to avoid embryo transfer in the same cycle in cases that exhibit E2 drop down. (Reprod Med Biol 2008; 7: 85-89).

Gonadotrophin releasing hormone antagonist in IVF/ICSI

OBJECTIVE

To study the efficacy of gonadotrophin releasing hormone (GnRH) antagonist in In-vitro-fertilization/Intracytoplasmic sperm injection (IVF/ICSI) cycles.

TYPE OF STUDY

Observational study.

SETTING

Reproductive Medicine Unit, Christian Medical College Hospital, Vellore, Tamil Nadu.

MATERIALS AND METHODS

GnRH antagonists were introduced into our practice in November 2005. Fifty-two women undergoing the antagonist protocol were studied and information gathered regarding patient profile, treatment parameters (total gonadotrophin dosage, duration of treatment, and oocyte yield), and outcomes in terms of embryological parameters (cleavage rates, implantation rates) and clinical pregnancy. These parameters were compared with 121 women undergoing the standard long protocol. The costs between the two groups were also compared.

MAIN OUTCOME

Clinical pregnancy rate.

RESULTS

The clinical pregnancy rate per embryo transfer in the antagonist group was 31.7% which was comparable to the clinical pregnancy rate in women undergoing the standard long protocol (30.63%). The costs between the two groups were comparable.

CONCLUSIONS

GnRH antagonist protocol was found to be effective and comparable to the standard long protocol regimen. In addition it was simple, convenient, and patient friendly.

The effects of GnRH antagonist on the endometrium of normally menstruating women

PURPOSE

To study the effects of GnRH antagonist (ganirelix-Orgalutran) on the endometrium of regularly menstruating women.

MATERIALS AND METHODS

Prospective, self-controlled study. The thirty-five volunteers were studied for two cycles: one as a control and the other, GnRH antagonist-treated cycles in which ganirelix 0.25 mg/d was given daily for 3 days, starting when the largest follicle reached 15 mm. In both cycles, serum estradiol, LH and endometrial thickness were measured when the largest follicle was > or =18 mm. Endometrial biopsy was performed on day 6 after ovulation for histological dating and morphometric study.

RESULTS

No statistical differences between histological dating and the endometrial thickness in the control and GnRH antagonist-treated cycles. All morphometric parameters were also not different. Serum estradiol and LH levels were significantly lower in GnRH antagonist-treated cycles.

CONCLUSION

GnRH antagonist has no effect on the endometrium of regularly menstruating women as assessed by either histological dating or morphometric analysis.

Cryopreserved blastocyst transfer: impact of gonadotropin-releasing hormone agonist versus antagonist in the previous oocyte retrieval cycles

OBJECTIVE

To assess any detrimental effect of gonadotropin-releasing hormone (GnRH) antagonists on oocyte quality and embryo development by comparing the outcome of cryopreserved-thawed blastocyst transfers for cycles using a GnRH agonist or GnRH antagonist protocol for the controlled ovarian stimulation in the oocyte retrieval cycle.

DESIGN

Retrospective comparative study.

SETTING

Private IVF center.

PATIENT(S)

Seventy-seven women who underwent cryopreserved-thawed blastocyst transfer.

INTERVENTION(S)

The patients were divided into two groups based on whether they had been treated using a GnRH agonist long protocol (n = 44) or a GnRH antagonist multiple-dose protocol (n = 33) during the previous oocyte retrieval cycle. Cryopreserved-thawed blastocysts were transferred after endometrial preparation without pituitary suppression using a GnRH agonist.

MAIN OUTCOME MEASURE(S)

Implantation and clinical pregnancy rates.

RESULT(S)

The postthaw survival rate and numbers of good quality blastocysts transferred were similar for the GnRH agonist and GnRH antagonist groups. Implantation and pregnancy rates for cryopreserved-thawed blastocyst transfer for the GnRH agonist group versus the GnRH antagonist group were 21.0% (25 of 119) versus 29.0% (27 of 93) and 38.6% (17 of 44) versus 51.5% (17 of 33), respectively, which was not statistically significantly different.

CONCLUSION(S)

No difference was found in terms of implantation and pregnancy rates when a GnRH agonist or GnRH antagonist was used in the previous oocyte retrieval cycle. Our results suggest that GnRH antagonists do not have a detrimental effect on oocyte quality or embryo development.

High Serum Estradiol Levels are not Detrimental to In Vitro Fertilization Outcome

OBJECTIVE

To evaluate the impact of high estradiol (E2) levels and a high number of retrieved oocytes on the outcome of in vitro fertilization (IVF) cycles.

MATERIALS AND METHODS

We retrospectively reviewed 274 IVF cycles. These patients were divided into five groups according to their peak E2 levels on the human chorionic gonadotropin day: < or = 2,000 pg/mL (130 cycles); 2,001-3,000 pg/mL (53 cycles); 3,001-4,000 pg/mL (46 cycles); 4,001-5,000 pg/mL (29 cycles); > 5,000 pg/mL (16 cycles). Fertilization, pregnancy, and implantation rates were analyzed between these groups. We also compared the outcome of IVF for high responders (> 15 retrieved oocytes) and normal responders (< or = 15 retrieved oocytes).

RESULTS

The oocyte fertilization and embryo cleavage rates were not significantly different among these five groups. Although decrease in pregnancy and implantation rates was observed when E2 levels were > 5,000 pg/mL compared with those having lower E2 levels, there were no statistically significant differences between these five groups. In addition, similar IVF outcome was detected for those cycles with > 15 oocytes and < or = 15 oocytes obtained.

CONCLUSION

High serum E2 levels and high oocyte yield are not detrimental to IVF outcome. More studies are needed to characterize the threshold E2 levels above which implantation rates are reduced.

Role of gonadotropin-releasing hormone antagonists in poor responders

OBJECTIVE

To evaluate the role of GnRH antagonists in poor-responder protocols.

DESIGN

Literature review.

CONCLUSION(S)

The optimum stimulation protocol for poor responders is unknown. Although many IVF programs currently use GnRH antagonists for poor responders, there have been only four prospective, randomized trials comparing GnRH antagonists to alternate protocols. None of these studies had sufficient power to evaluate a difference in pregnancy rates (PRs), and in all four cases, IVF outcomes were comparable. Nevertheless, interest in the use of GnRH antagonists in poor responders has continued. GnRH antagonists may be associated with simpler stimulation protocols, lower gonadotropin requirements, reduced patient costs, and shorter downtimes between consecutive cycles. However, the greatest advantage of GnRH antagonists may lie in the ability to assess ovarian reserves immediately prior to deciding whether or not to initiate gonadotropin stimulation. The ability to respond to cycle-to-cycle variation in antral follicle counts may allow the optimization of oocyte yield and reduce cycle cancellation rates. It remains to be seen if this approach (initiating gonadotropins only in cycles where an adequate antral follicle count is present) also translates into higher clinical PRs for poor responders.

GnRH antagonists in ovarian stimulation for ICSI with oocyte restriction: a matched, controlled study

Italian legislation regarding reproductive medicine limits the number of embryos transferred per attempt to three. Thus, in order to achieve pregnancy, more IVF cycles may be required, generating a need for methods of ovarian stimulation with fewer side effects. The gonadotrophin-releasing hormone (GnRH) antagonists have several advantages in this respect, but there is a debate regarding a possible lower pregnancy rate from resulting cycles. This study evaluated the clinical applicability of GnRH antagonists for ovarian stimulation in young women undergoing intracytoplasmic sperm injection (ICSI) in which only three oocytes can be fertilized. The 200 women treated with GnRH antagonist had a significantly shorter stimulation and lower gonadotrophin consumption, oestradiol concentration, total and mature oocyte recovery as compared with 200 matched controls treated with GnRH agonist. No differences were found between the groups in the number of normal zygotes, total cleaved, transferred and high quality embryos, or in the clinical outcomes. Thus, the previously reported lower pregnancy rate in GnRH antagonist cycles may be related to the oocyte characteristics. Finally, under conditions of oocyte number restriction, the GnRH antagonist-based cycles may be proposed as an efficacious, safe and minimally invasive alternative to GnRH agonist in a standard long protocol.

Similar outcome for cryopreserved embryo transfer following GnRH-antagonist/GnRH-agonist, GnRH-antagonist/HCG or long protocol ovarian stimulation

The pregnancy rates after triggering of final oocyte maturation with gonadotrophin-releasing hormone (GnRH) agonist in GnRH-antagonist ovarian stimulation protocols are lower than those following triggering with human chorionic gonadotrophin (HCG). Furthermore, lower pregnancy rates following GnRH-antagonist protocols compared with long GnRH-agonist protocols have been reported. The differences might be due to an impact on oocyte number and quality or on the endometrium. If any stimulation protocol had a negative impact on oocyte quality, then further evidence of this effect would be observed following frozen-thawed embryo transfer originating from that stimulation cycle. The outcome of frozen-thawed embryo transfer was retrospectively analysed using the long protocol with triptorelin depot 3.75 mg (n = 215) or 0.1 mg/day (n = 83), or GnRH-antagonist protocol with either HCG (n = 69) or GnRH-agonist (n = 25) for final oocyte maturation. The outcomes measured were implantation rate, clinical pregnancy rate, ongoing pregnancy rate and embryo survival rate. All outcomes were similar in the four groups. It is concluded that the potential for frozen-thawed embryos to implant and develop following transfer is independent of the GnRH-analogue and the final oocyte maturation protocol used in the collection cycle. Lower IVF embryo transfer success using GnRH-antagonist/GnRH-agonist protocol does not appear to be related to an adverse effect on oocyte quality.

Recombinant human follicle-stimulating hormone alters maternal ovarian hormone concentrations and the uterus and perturbs fetal development in mice

Gonadotropins are routinely administered to produce multiple oocytes for clinical in vitro fertilization (IVF) treatment, laboratory research, and livestock industries. Studies in mice have shown gonadotropin stimulation using equine chorionic gonadotropin (eCG) affects the endometrium, implantation, and fetal development. Evidence from clinical studies also indicates that stimulation with recombinant human follicle-stimulating hormone (rhFSH) may be detrimental to the endometrium and implantation rates. We investigated the effect of rhFSH in mice on maternal plasma hormone concentrations and uterine gene and protein expression and the effect of a stimulated maternal environment on pregnancy. Adult females were stimulated with rhFSH or eCG, followed by human chorionic gonadotropin (hCG). On day 4 of pseudopregnancy, mice either had embryos transferred to the uterus or were killed, and blood and uterine samples were collected. Pregnancy outcomes were examined on day 15. Gonadotropin stimulation increased plasma progesterone concentrations on day 4 compared with controls, whereas estradiol concentrations were unaffected. Stimulation also reduced uterine leukemia inhibitory factor (Lif) mRNA, but the expression of estrogen and progesterone receptors (Esr1 and Pgr), homeobox gene Hoxa10, and Vegf mRNA were unchanged. Furthermore, distribution of uterine PGR protein expression was altered by stimulation, but LIF protein was unchanged. Stimulated embryo transfer recipients had lower pregnancy rates than controls, and fetuses from the rhFSH group had reduced weight, length, and maturity. These results demonstrate that gonadotropin stimulation with rhFSH or eCG alters the preimplantation maternal environment, which results in reduced pregnancy rates and fetal development in the mouse.

Progesterone supplementation to prevent recurrent miscarriage and to reduce implantation failure in assisted reproduction cycles

Implantation failure has been questioned for many cases of recurrent miscarriage and unsuccessful assisted reproduction. The exact cause of implantation failure is not known, but luteal phase defect is encountered in many of these cases. Consequently, women with recurrent miscarriages have been treated with progesterone supplementation with various degrees of success, and a recent meta-analysis has shown trends for improved live birth rates in those women. Progesterone probably acts as an immunological suppressant blocking T-helper (Th)1 activity and inducing release of Th2 cytokines. Numerous studies have confirmed that ovarian stimulation used in assisted reproduction is associated with luteal phase insufficiency, even when gonadotrophin-releasing hormone antagonists are used. In those patients, advanced endometrial histological maturity and a decrease in the concentration of cytoplasmic progesterone receptors are observed. Progesterone supplementation results in a trend towards improved ongoing and clinical pregnancy rates, except in patients treated with human menopausal gonadotrophin-only regimens, in whom ongoing pregnancy rates increase significantly. More randomized controlled trials are needed to increase the power of the currently available meta-analyses to further evaluate progesterone supplementation in both conditions.

Estradiol production during controlled ovarian hyperstimulation correlates with treatment outcome in women undergoing in vitro fertilization–embryo transfer

OBJECTIVE

To study the value of E(2) production during controlled ovarian hyperstimulation (COH) in predicting IVF-ET outcome.

DESIGN

Historical cohort.

SETTING

Academic infertility center.

PATIENT(S)

A cohort of 270 patients who completed 324 consecutive IVF-ET treatment cycles.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Area under the curve for E(2) levels (AUC-E(2)) from the first day of COH until the day of hCG administration was calculated and cycles grouped into low, average, and high AUC-E(2) groups. Clinical pregnancy rates per cycle were compared among the three groups, and correlations with AUC-E(2) values were calculated for all patients and after sub-grouping according to age, COH protocol and infertility diagnosis.

RESULT(S)

Cycles with low and high AUC-E(2) values had significantly lower pregnancy rates particularly in patients 35 years or older. There was a positive correlation between AUC-E(2) and pregnancy rates up to a certain AUC-E(2) level above which a negative correlation was found. The turning point between positive and negative correlations occurred at a significantly lower AUC-E(2) level in patients 35 years or older.

CONCLUSIONS

Estradiol production during COH correlates with IVF-ET outcome. Women >35 years of age seem more vulnerable to high E(2) levels.

The human endometrium as a fertility-determining factor

Intensive research work has been performed to better understand the regulation of the endometrium and its clinical implications to improve implantation. Although many proteins and molecules may influence endometrial development, their co-ordinated contribution to the implantation process is still poorly understood and a translation into clinical use has not sufficiently been performed. Clinical evaluation of the endometrium by ultrasound and other techniques, like endometrial biopsy and analysis of uterine secretions, has been intensively studied and therapeutic options to improve endometrial function have been suggested and tested. Systemic treatment with heparin, aspirin or corticosteroids did not result in improved implantation rates. Gene therapy and cervical treatment, e.g. with seminal plasma, are still in the phase of clinical research. Therefore, this review focuses on different aspects of endometrial research, which all contribute to the diagnosis, evaluation and therapy of endometrial function and dysfunction. First, the endometrial development towards a receptive milieu is described. Second, the actual clinical evaluation of endometrial receptivity, possible therapeutic strategies and in particular, the evaluation of endometrial function in the non-natural situation of hormonal stimulation is critically evaluated. In conclusion, the endometrium shall be considered as an important fertility-determining factor and therapeutic options should be developed in near future.

Ovarian stimulation with GnRH agonist, but not GnRH antagonist, partially restores the expression of endometrial integrin 3 and leukaemia-inhibitory factor and improves uterine receptivity in mice

BACKGROUND

The impact of different ovarian stimulation (OS) protocols on endometrial receptivity remains controversial. In this study, the effects of different OS on the expression of endometrial integrin beta3 subunit and leukaemia-inhibitory factor (LIF) during the implantation window and the implantation rate in mice were investigated.

METHODS

Three OS protocols were used, involving either pregnant mare's serum gonadotrophin (PMSG) alone, PMSG plus GnRH agonist or PMSG plus GnRH antagonist. Uterus samples were collected at 48 h after OS or ovulation and were detected with immunohistochemistry, Western blot and RT-PCR analyses. Normal embryos at gestation day 4 were transferred into the uteri of mice in the control and OS groups.

RESULTS

All OS groups showed a significant decrease in the expression of both the endometrial integrin beta3 subunit and LIF during the implantation window and the implantation rate. Among the three OS groups, GnRH agonist-treated mice showed a higher endometrial integrin beta3 subunit and LIF expression and a higher implantation rate. No significant difference was found in the measured indices between the GnRH antagonist and PMSG groups.

CONCLUSIONS

OS may inhibit the expression of endometrial integrin beta3 subunit and LIF and impair endometrial receptivity in mice. OS with GnRH agonist, but not GnRH antagonist, may partially restore the endometrial physiological secretion and improve uterine receptivity.

Cetrorelix in an oral contraceptive-pretreated stimulation cycle compared with buserelin in IVF/ICSI patients treated with r-hFSH: a randomized, multicentre, phase IIIb study

BACKGROUND

The aim of this study was to assess the non-inferiority of an oral contraceptive (OC)-pretreated cetrorelix regimen and a buserelin regimen in IVF/ICSI patients treated with r-hFSH in terms of total number of oocytes retrieved.

METHODS

Multicentre, randomized study. One hundred and eighty two patients were randomized to receive cetrorelix with OC pretreatment (n = 91) or to receive buserelin (n = 91). The cetrorelix group started with daily OCs on cycle day 5 and continued for 21-28 days. Cetrorelix (0.25 mg) was given daily from stimulation day 6 up to and including the day of r-hCG administration. The buserelin group started with buserelin (500 microg/day) for at least 10 days until down-regulation was achieved, after which the dose was reduced to daily 200 microg up to and including the day of r-hCG administration. r-hFSH was started in both groups on a Friday, in the cetrorelix group 5 days after the last OC pill intake. Both regimens were followed by a standard IVF or ICSI procedure. The primary efficacy endpoint was the number of oocytes retrieved per patient.

RESULTS

Number of oocytes, cancellation rates, r-hFSH requirements, number of oocyte retrievals during the weekend or public holiday and number of pregnancies were similar in both groups. Both treatment regimens were well tolerated.

CONCLUSIONS

Cetrorelix pretreated with OCs resulted in similar number of oocytes retrieved compared with a long buserelin protocol. Both regimens were well tolerated and allowed scheduling of the oocyte retrieval, with only small number of retrievals falling on a weekend or public holiday.