The effect of elevated progesterone levels before oocyte retrieval in women undergoing ovarian stimulation for IVF treatment on the genomic profile of peri-implantation endometrium

Contributing factors for pregnancy outcomes in women with PCOS after their first FET treatment: a retrospective cohort study

OBJECTIVE

We aim to explore the contributing factors of clinical pregnancy outcomes in PCOS patients undergoing their first FET treatment.

METHODS

A retrospective analysis was conducted on 574 PCOS patients undergoing their first FET treatment at a private fertility center from January 2018 to December 2021.

RESULTS

During the first FET cycle of PCOS patients, progesterone levels (aOR 0.109, 95% CI 0.018-0.670) and endometrial thickness (EMT) (aOR 1.126, 95% CI 1.043-1.419) on the hCG trigger day were associated with the clinical pregnancy rate. Similarly, progesterone levels (aOR 0.055, 95% CI 0.007-0.420) and EMT (aOR 1.179, 95% CI 1.011-1.376) on the hCG trigger day were associated with the live birth rate. In addition, AFC (aOR 1.179, 95% CI 1.011-1.376) was found to be a risk factor for preterm delivery.

CONCLUSIONS

In women with PCOS undergoing their first FET, lower progesterone levels and higher EMT on hCG trigger day were associated with clinical pregnancy and live birth, and AFC was a risk factor for preterm delivery. During FET treatment, paying attention to the patient's endocrine indicators and follicle status may have a positive effect on predicting and improving the pregnancy outcome of PCOS patients.

Premature Progesterone Rise Is Associated with Higher Cumulative Live Birth Rate with Freeze-All Strategy

Background/Objectives: This paper undertakes an investigation into the implications of premature progesterone rise (PPR) on pregnancy outcomes in freeze-all strategy cycles. Methods: A retrospective cohort study encompassing 675 IVF/ICSI cycles using a freeze-all strategy was enrolled. The cycles were categorized into two groups based on serum progesterone levels at the time of hCG administration: 526 cycles had levels below 1.5 ng/mL, while 149 cycles had levels equal to or above 1.5 ng/mL. Results: The findings revealed a significantly higher number of mature follicles and retrieved oocytes in patients with PPR across all AMH categories. Multiple analyses revealed factors influencing PPR, including the duration of induction and the number of retrieved oocytes. Within the same oocyte retrieval number group, patients with PPR demonstrated non-inferior pregnancy outcomes compared to non-PPR patients. Upon adjustment for age, AMH, and total follicle-stimulating hormone (FSH) dosage, PPR maintained a positive correlation with the cumulative live birth rate (LBR). Conclusions: The study showed that PPR correlates with an increase in retrieved oocytes while maintaining similar embryo quality and oocyte retrieval rates and results in a higher cumulative LBR.

High progesterone levels on the day after HCG injection has no effect on clinical pregnancy outcomes in in vitro fertilization-embryo transfer

Background

This study investigates the potential impact of high progesterone (P) level on the day following human chorionic gonadotropin (HCG) injection on the clinical pregnancy outcomes of in vitro fertilization-embryo transfer (IVF-ET).

Methods

Retrospective analysis was conducted on 6418 cycles of IVF-ET performed at Liuzhou Maternal and Child Health Hospital between August 2020 to December 2021. Excluding cycles with progesterone levels ≥1.5ng/ml on HCG injection, a total of 781 cycles were identified according to the standard, and they were divided into five groups according to the progesterone level on the day after HCG: Group A: progesterone level < 2.5 ng/ml (n = 128); Group B: 2.5 ng/ml ≤ progesterone level < 3.5 ng/ml (n = 174); Group C: 3.5 ng/ml ≤ progesterone level < 4.5 ng/ml (n = 153); Group D: 4.5 ng/ml ≤ progesterone level < 5.5 ng/ml (n = 132); Group E progesterone level ≥5.5 ng/ml(n=194). Comparative analyses of clinical data, including general clinical data, and clinical pregnancy outcomes such as clinical pregnancy rate, miscarriage rate, and live birth rate were performed among these groups.

Results

There were significant differences in estradiol levels on HCG injection, but there were no differences in available embryo rate, clinical pregnancy rate, miscarriage rate, and live birth rate. Binary logistic regression analysis showed that there was no significant correlation between P level on the day after HCG injection and the live birth rate.

Conclusion

Under the condition of low P level on HCG injection, high progesterone levels on the day after HCG injection does not affect the clinical pregnancy outcomes of IVF-ET.

Progestogens for prevention of luteinising hormone (LH) surge in women undergoing controlled ovarian hyperstimulation as part of an assisted reproductive technology (ART) cycle

BACKGROUND

Currently, gonadotrophin releasing hormone (GnRH) analogues are used to prevent premature ovulation in ART cycles. However, their costs remain high, the route of administration is invasive and has some adverse effects. Oral progestogens could be cheaper and effective to prevent a premature LH surge.

OBJECTIVES

To evaluate the effectiveness and safety of using progestogens to avoid spontaneous ovulation in women undergoing controlled ovarian hyperstimulation (COH).

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Group trials register, CENTRAL, MEDLINE, Embase and PsycINFO in Dec 2021. We contacted study authors and experts to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that included progestogens for ovulation inhibition in women undergoing controlled ovarian hyperstimulation (COH).

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane, including the risk of bias (RoB) assessment. The primary review outcomes were live birth rate (LBR) and oocyte pick-up cancellation rate (OPCR). Secondary outcomes were clinical pregnancy rate (CPR), cumulative pregnancy, miscarriage rate (MR), multiple pregnancies, LH surge, total and MII oocytes, days of stimulation, dose of gonadotropins, and moderate/severe ovarian hyperstimulation syndrome (OHSS) rate. The primary analyses were restricted to studies at overall low and some concerns RoB, and sensitivity analysis included all studies. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We included 14 RCTs (2643 subfertile women undergoing ART, 47 women used oocyte freezing for fertility preservation and 534 oocyte donors). Progestogens versus GnRH antagonists We are very uncertain of the effect of medroxyprogesterone acetate (MPA) 10 mg compared with cetrorelix on the LBR in poor responders (odds ratio (OR) 1.25, 95% confidence interval (CI) 0.73 to 2.13, one RCT, N = 340, very-low-certainty evidence), suggesting that if the chance of live birth following GnRH antagonists is assumed to be 18%, the chance following MPA would be 14% to 32%. There may be little or no difference in OPCR between progestogens and GnRH antagonists, but due to wide Cs (CIs), we are uncertain (OR 0.92, 95%CI 0.42 to 2.01, 3 RCTs, N = 648, I² = 0%, low-certainty evidence), changing the chance of OPCR from 4% with progestogens to 2% to 8%. Given the imprecision found, no conclusions can be retrieved on CPR and MR. Low-quality evidence suggested that using micronised progesterone in normo-responders may increase by 2 to 6 the MII oocytes in comparison to GnRH antagonists. There may be little or no differences in gonadotropin doses. Progestogens versus GnRH agonists Results were uncertain for all outcomes comparing progestogens with GnRH agonists. One progestogen versus another progestogen The analyses comparing one progestogen versus another progestogen for LBR did not meet our criteria for primary analyses. The OPCR was probably lower in the MPA 10 mg in comparison to MPA 4 mg (OR 2.27, 95%CI 0.90 to 5.74, one RCT, N = 300, moderate-certainty evidence), and MPA 4 mg may be lower than micronised progesterone 100 mg, but due to wide CI, we are uncertain of the effect (OR 0.81, 95%CI 0.43 to 1.53, one RCT, N = 300, low-certainty evidence), changing the chance of OPCR from 5% with MPA 4 mg to 5% to22%, and from 17% with micronised progesterone 100 mg to 8% to 24%. When comparing dydrogesterone 20 mg to MPA, the OPCR is probably lower in the dydrogesterone group in comparison to MPA 10 mg (OR 1.49, 95%CI 0.80 to 2.80, one RCT, N = 520, moderate-certainty evidence), and it may be lower in dydrogesterone group in comparison to MPA 4 mg but due to wide confidence interval, we are uncertain of the effect (OR 1.19, 95%CI 0.61 to 2.34, one RCT, N = 300, low-certainty evidence), changing the chance of OPCR from 7% with dydrogesterone 20 to 6-17%, and in MPA 4 mg from 12% to 8% to 24%. When comparing dydrogesterone 20 mg to micronised progesterone 100 mg, the OPCR is probably lower in the dydrogesterone group (OR 1.54, 95%CI 0.94 to 2.52, two RCTs, N=550, I² = 0%, moderate-certainty evidence), changing OPCR from 11% with dydrogesterone to 10% to 24%. We are very uncertain of the effect in normo-responders of micronised progesterone 100 mg compared with micronised progesterone 200 mg on the OPCR (OR 0.35, 95%CI 0.09 to 1.37, one RCT, N = 150, very-low-certainty evidence). There is probably little or no difference in CPR and MR between MPA 10 mg and dydrogesterone 20 mg. There may be little or no differences in MII oocytes and gonadotropins doses. No cases of moderate/severe OHSS were reported in most of the groups in any of the comparisons.

AUTHORS' CONCLUSIONS

Little or no differences in LBR may exist when comparing MPA 4 mg with GnRH agonists in normo-responders. OPCR may be slightly increased in the MPA 4 mg group, but MPA 4 mg reduces the doses of gonadotropins in comparison to GnRH agonists. Little or no differences in OPCR may exist between progestogens and GnRH antagonists in normo-responders and donors. However, micronised progesterone could improve by 2 to 6 MII oocytes. When comparing one progestogen to another, dydrogesterone suggested slightly lower OPCR than MPA and micronised progesterone, and MPA suggested slightly lower OPCR than the micronised progesterone 100 mg. Finally, MPA 10 mg suggests a lower OPCR than MPA 4 mg. There is uncertainty regarding the rest of the outcomes due to imprecision and no solid conclusions can be drawn.

Impact of progesterone concentration on human chorionic gonadotropin trigger day on clinical outcomes with one top-quality cleavage-stage embryo or blastocyst transfer in fresh in vitro fertilization cycles

Objective

To investigate the impact of the progesterone concentration on the human chorionic gonadotropin (hCG) trigger day on clinical outcomes with an antagonist protocol.

Methods

The retrospective cohort study included a total of 1,550 fresh autologous ART cycles with one top-quality embryo transfer. Multivariate regression analysis, curve fitting, and threshold effect analysis were performed.

Results

A significant association was found between the progesterone concentration and clinical pregnancy rate (adjusted OR, 0.77; 95% CI, 0.62-0.97; P = 0.0234), especially in blastocyst transfer (adjusted OR, 0.56; 95% CI, 0.39-0.78; P = 0.0008). The association between the progesterone concentration and the ongoing pregnancy rate was insignificant. The clinical pregnancy rate showed a linear relationship with an increased progesterone concentration in cleavage-stage embryo transfer. In blastocyst transfer, as the progesterone concentration increased, the clinical and ongoing pregnancy rates showed a parabolic reverse-U curve; the curve initially increased before declining at high progesterone concentrations. The clinical pregnancy rate increased with a progesterone concentration up to 0.80 ng/mL rather than tended to be stable. The clinical pregnancy rate significantly decreased when the progesterone concentration was ≥0.80 ng/mL.

Conclusion

The progesterone concentration on the hCG trigger day exhibits a curvilinear relationship with pregnancy outcomes in blastocyst transfer cycles, and the optimal threshold of the progesterone concentration is 0.80 ng/mL.

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.

Elevated serum progesterone levels on the hCG trigger day have a negative impact on the live birth rate in the first fresh IVF-ET cycle

To investigate whether there is a relationship between elevated serum progesterone (PROG) on the hCG trigger day and the live birth rate (LBR) in IVF/ICSI cycles, the retrospective analysis was carried out from the patients undergoing the first ART cycles throughout 2016. The PROG levels were measured on the hCG trigger day. The LBR, clinical pregnancy rate (CPR), implantation rate (IR) and other parameter rate values were compared among the three different PROG elevations. A total of 2550 IVF/ICSI cycles fulfilling all the inclusion and exclusion criteria were selected. Finally, three groups [PROG <0.40 ng/mL, 0.40 ≤ PROG < 1.5 ng/mL, PROG ≥ 1.5 ng/mL] were categorised based on the serum PROG levels. LBR, CPR and IR declined as the PROG value increased, while there was no difference in the embryo utilisation rates. Serum PROG levels on the day of hCG administration were negatively associated with the LBR, even in ETs with a good prognosis.Impact StatementWhat is already known on this subject? The clinical effects of PROG are still controversial. Some studies have confirmed that there was not too much association between premature elevation of PROG and live birth, some are still convincing that there is a negative correlation and will result in ART cycles of pregnancy and LBR reduction.What do the results of this study add? Our data substantiated that the high serum PROG level had the lowest LBR, IR and CPR, but the embryo utilisation rate may not have too much to do with the elevated PROG.What are the implications of these findings for clinical practice and/or further research? This study further strengthens the negative impact of elevated PROG levels on pregnancy outcomes, and suggests that frozen thawed embryo transfer appears to be a reasonable and advantageous approach for this subset of patients.

Endometrial Receptivity Testing and Therapy in Assisted Reproductive Treatment

Assisted reproductive treatment (ART) gave numerous couples the chance to have their biological child. Improvement in laboratory and culture conditions allows for selection of embryos with the best developmental potential, although replacement of these top-quality embryos does not, however, guarantee reproductive success. Endometrial receptivity is essential for pregnancy establishment and may be the limiting factor for the observed pregnancy rates with ART. Multiple modalities have been in use to assess endometrial receptivity, with ultrasound assessment of the endometrial morphology most commonly used due to its noninvasive nature and availability. Utilization of various "omics" increases our understanding of endometrial receptivity and selectivity; however, significantly more work is required to develop clinically relevant and validated tests of endometrial receptivity and treatments which could improve a suboptimal endometrial milieu. Current evidence for and against use of various tests of endometrial receptivity in women undergoing ART is presented in this article.

Is a freeze-all policy the optimal solution to circumvent the effect of late follicular elevated progesterone? A multicentric matched-control retrospective study analysing cumulative live birth rate in 942 non-elective freeze-all cycles

STUDY QUESTION

Is late follicular elevated progesterone (LFEP) in the fresh cycle hindering cumulative live birth rates (CLBRs) when a freeze only strategy is applied?

SUMMARY ANSWER

LFEP in the fresh cycle does not affect the CLBR of the frozen transfers in a freeze only approach, nor the embryo freezing rate.

WHAT IS KNOWN ALREADY

Ovarian stimulation promotes the production of progesterone (P) which has been demonstrated to have a deleterious effect on IVF outcomes. While there is robust evidence that this elevation produces impaired endometrial receptivity, the impact on embryo quality remains a matter of debate. In particular, previous studies have shown that LFEP is associated with a hindered CLBR. However, most clinical insight on the effect of progesterone on embryo quality in terms of CLBRs have focused on embryo transfers performed after the fresh transfer, thus excluding the first embryo of the cohort. To be really informative on the possible detrimental effects of LFEP, evidence should be derived from freeze-all cycles where no fresh embryo transfer is performed in the presence of progesterone elevation, and the entire cohort of embryos is cryopreserved.

STUDY DESIGN, SIZE, DURATION

This was a matched case-control, multicentre (three centres), retrospective analysis including all GnRH antagonist ICSI cycles in which a freeze all (FA) policy of embryos on day 3/5/6 of embryonic development was applied between 2012 and 2018. A total of 942 patients (471 cases with elevated P and 471 matched controls with normal P values) were included in the analysis. Each patient was included only once.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The sample was divided according to the following P levels on the day of ovulation triggering: <1.50 ng/ml and ≥1.50 ng/ml. The matching of the controls was performed according to age (±1 year) and number of oocytes retrieved (±10%). The main outcome was CLBR defined as a live-born delivery after 24 weeks of gestation.

MAIN RESULTS AND THE ROLE OF CHANCE

The baseline characteristics of the two groups were similar. Estradiol levels on the day of trigger were significantly higher in the elevated P group. There was no significant difference in terms of fertilisation rate between the two groups. The elevated P group had significantly more cleavage stage frozen embryos compared to the normal P group while the total number of cryopreserved blastocyst stage embryos was the same. The CLBR did not differ between the two study groups (29.3% and 28.2% in the normal versus LFEP respectively, P = 0.773), also following confounder adjustment using multivariable GEE regression analysis (accounting for age at oocyte retrieval, total dose of FSH, progesterone levels on the day of ovulation trigger, day of freezing, at least one top-quality embryo transferred and number of previous IVF cycles, as the independent variables).

LIMITATIONS, REASONS FOR CAUTION

This is a multicentre observational study based on a retrospective data analysis. Better extrapolation of the results could be validated by performing a prospective analysis.

WIDER IMPLICATIONS OF THE FINDINGS

This is the first study demonstrating that LFEP in the fresh cycle does not hinder CLBR of the subsequent frozen cycles in a FA approach. Thus, a FA strategy circumvents the issue of elevated P in the late follicular phase.

STUDY FUNDING/COMPETING INTEREST(S)

No funding was received for this study. Throughout the study period and manuscript preparation, authors were supported by departmental funds from: Centre for Reproductive Medicine, Brussels, Belgium; Infertility Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Centro Scienze Natalità, San Raffaele Scientific Institute, Milan, Italy; and IVI-RMA, Lisbon, Portugal. E.S. has competing interests with Ferring, Merck-Serono, Theramex and Gedeon-Richter outside the submitted work. E.P. reports grants from Ferring, grants and personal fees from Merck-Serono, grants and personal fees from MSD and grants from IBSA outside the submitted work. All the other authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Uterine natural killer cells: from foe to friend in reproduction

BACKGROUND

Recurrent miscarriage and pre-eclampsia are common reproductive disorders, but their causes are often unknown. Recent evidence has provided new insight into immune system influences in reproductive disorders. A subset of lymphocytes of the innate immune system known as uterine natural killer (uNK) cells are now recognized as fundamental to achieving embryo implantation and successful pregnancy, but were initially attributed a bad reputation. Indeed, immune therapies have been developed to treat the 'exaggerated' immune response from uNK cells. These treatments have been based on studies of peripheral blood natural killer (pbNK) cells. However, uNK cells and pbNK cells have different phenotypic and functional characteristics. The functions of uNK cells are closely related to their interactions with the extravillous trophoblast cells (EVTs) and spiral arteries, which underlie an essential role in regulating vascular function, controlling trophoblast invasion and promoting placental development. EVTs express MHC molecules of class I HLA-C/E/G/F, while uNK cells express, among other receptors, killer cell immunoglobulin-like receptors (KIRs) that bind to HLA-C or CD94/NKG2A inhibitory receptors, and then bind HLA-E. Associations of certain KIR/HLA-C combinations with recurrent miscarriage, pre-eclampsia, and foetal growth restriction and the interactions between uNK cells, trophoblasts and vascular cells have led to the hypothesis that uNK cells may play a role in embryo implantation.

OBJECTIVE AND RATIONALE

Our objective was to review the evolution of our understanding of uNK cells, their functions, and their increasingly relevant role in reproduction.

SEARCH METHODS

Relevant literature through June 2020 was retrieved using Google Scholar and PubMed. Search terms comprised uNK cells, human pregnancy, reproductive failure, maternal KIR and HLA-C, HLA-E/G/F in EVT cells, angiogenic cytokines, CD56+ NK cells, spiral artery, oestrogen and progesterone receptors, KIR haplotype and paternal HLA-C2.

OUTCOMES

This review provides key insights into the evolving conceptualization of uNK cells, from their not-so-promising beginnings to now, when they are considered allies in reproduction. We synthesized current knowledge about uNK cells, their involvement in reproduction and their main functions in placental vascular remodeling and trophoblast invasion. One of the issues that this review presents is the enormous complexity involved in studying the immune system in reproduction. The complexity in the immunology of the maternal-foetal interface lies in the great variety of participating molecules, the processes and interactions that occur at different levels (molecular, cellular, tissue, etc.) and the great diversity of genetic combinations that are translated into different types of responses.

WIDER IMPLICATIONS

Insights into uNK cells could offer an important breakthrough for ART outcomes, since each patient could be assessed based on the combination of HLA and its receptors in their uNK cells, evaluating the critical interactions at the materno-foetal interface. However, owing to the technical challenges in studying uNK cells in vivo, there is still much knowledge to gain, particularly regarding their exact origin and functions. New studies using novel molecular and genetic approaches can facilitate the identification of mechanisms by which uNK cells interact with other cells at the materno-foetal interface, perhaps translating this knowledge into clinical applicability.

Occurrence of smooth endoplasmic reticulum aggregates in metaphase II oocytes: relationship with stimulation protocols and outcome of ICSI and IVF cycles

STUDY QUESTION

Is there any association between the appearance of smooth endoplasmic reticulum aggregates (SERa) in oocytes and ovarian stimulation, embryological, clinical and neonatal outcomes of ICSI and IVF cycles?

SUMMARY ANSWER

A suboptimal prolonged ovarian stimulation is detrimental to oocytes by inducing the occurrence of SERa, which reduces the reproductive potential of oocytes.

WHAT IS KNOWN ALREADY

Controlled ovarian stimulation recruits oocytes of different qualities. Based on current evidence, it was agreed that non-homogeneous cytoplasm may represent the normal variability among oocytes rather than a dysmorphism with developmental significance. The only exception is the appearance of SERa within the ooplasm. Owing to the lack of univocal evidence in this literature about the safety of injecting oocytes with SERa and the mechanism responsible for the occurrence of SERa, this topic is still a matter of debate.

STUDY DESIGN, SIZE, DURATION

A retrospective, longitudinal cohort study performed at a tertiary level public infertility center. We included 1662 cycles (180 SERa+ and 1482 SERa-) from 1129 women (age: 20-44 years) who underwent IVF/ICSI treatments in 2012-2019. The SERa+ cycles had at least one SERa+ oocyte in the oocyte cohort. The SERa- cycles had morphologically unaffected oocytes.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We collected stimulation data and embryological, clinical, neonatal outcomes of SERa- and SERa+ cycles and oocytes.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, 347 out of 12 436 metaphase II oocytes (2.8%) were affected by SER. We performed only 12 transfers involving at least one SERa+ embryo. Stimulation length (P = 0.002), serum progesterone (P = 0.004) and follicle size (P = 0.046) at trigger, number of retrieved (P = 0.004) and metaphase II (P = 0.0001) oocytes were significantly higher in SERa+ than SERa- cycles. Fertilization rate was significantly (P < 0.0001) reduced in SERa+ cycles and oocytes compared to SERa- counterparts. Embryos of SERa+ cycles had a lower blastocyst formation rate compared to embryos of SERa- cycles (P = 0.059). Statistical analysis according to a generalized estimating equation model performed at patient level demonstrated that the duration of ovarian stimulation was predictive of SERa+ oocytes appearance. The clinical success of SERa+ cycles was lower than SERa- cycles, although no differences in neonatal birthweights or malformations were recorded in sibling unaffected oocytes of SERa+ cycles.

LIMITATIONS, REASONS FOR CAUTION

Given that SERa+ oocytes were discarded in our center for years and transfers of embryos originating from affected oocytes were generally avoided, clinical outcomes of SERa+ cycles are largely attributable to the transfer of embryos derived from unaffected oocytes of SERa+ cycles and we did not have data about newborns from affected oocytes, since none of the transfers involving SERa+ embryos resulted in a progressive clinical pregnancy.

WIDER IMPLICATIONS OF THE FINDINGS

For the first time, we speculate that the late-follicular phase elevated serum progesterone caused by a suboptimal prolonged ovarian stimulation may be detrimental to the oocytes by inducing the occurrence of SERa, resulting in negative effects on their reproductive potential. This raises the question of whether some stimulation regimens could be worse than others and a change in stimulation protocol would reduce the possibility of producing oocytes with suboptimal maturation. In particular, our data highlight the importance of correct timing of the trigger in order to maximize oocyte collection, not only in terms of numerosity but also their reproductive potential.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

N/A.

The number of previous failed embryo transfer cycles is an independent factor affecting implantation rate in women undergoing IVF/ICSI treatment: A retrospective cohort study

ABSTRACT

The implantation rate (IR) in assisted reproductive technologies such as in vitro fertilization (IVF) and intracytoplasmic sperm injection is affected by many different factors such as age, quality of embryo, and stage of embryo development. This study aimed to investigate to what extent the number of previous failed embryo transfer cycles is an independent factor affecting IR.This was a single-center, retrospective cohort study of a consecutive series of 6376 day-3 embryo transfer (ET) cycles following IVF between January 2012 and August 2018. None of the subjects underwent endometrial scratch/injury prior to the treatment cycle, or received intravenous immunoglobulin, steroid, dehydroepiandrosterone, intralipid or heparin during the treatment with the aim of improving implantation rates.Multiple regression analysis showed that the 3 most important independent factors affecting the IR, in decreasing of importance: age, frozen or fresh embryo transfer and the number of previous ET cycles. Having controlled for 2 of the more important confounding variables including maternal age and the type of embryo, the IR in women who had 0, 1, 2, and 3 or more previous failed ET cycles were 45.8%, 35.9%, 31.2%, 21.0%, respectively (P < .001).Repeated implantation failure is a significant independent factor affecting the IR. The number of previous failed ET cycles should be considered in counselling women regarding the prognosis of a further IVF-ET treatment cycle.

Response to ovulation trigger is correlated to late follicular phase progesterone levels: A hypothesis explaining reduced reproductive outcomes caused by increased late follicular progesterone rise

STUDY QUESTION

Is there an association between progesterone (P4) levels on the day of hCG or GnRH trigger and on the day of oocyte retrieval in IVF/ICSI cycles?

SUMMARY ANSWER

A significant positive correlation between P4 levels on the day of trigger and the day of oocyte retrieval is seen; HCG trigger induces a steeper P4 increase than GnRHa trigger.

WHAT IS KNOWN ALREADY

FSH induces LH receptor (LHR) expression on granulosa cells, and LHR produces progesterone when exposed to LH-like activity. FSH per se also to some extent induces P4 secretion. Late follicular phase progesterone rise has been associated with reduced reproductive outcomes.

STUDY DESIGN, SIZE, DURATION

This study is based on data from a previously published RCT conducted from 2009 to 2011.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 384 participants were enrolled; 199 received 5000 IU hCG and 185 received buserelin 0.5 mg for triggering ovulation. P4 was measured on the day of ovulation induction and on the day of oocyte retrieval. FSH consumption and number of retrieved follicles were recorded.

MAIN RESULTS AND THE ROLE OF CHANCE

A significant linear relationship between P4 on the day of ovulation induction and oocyte retrieval was seen in the hCG trigger group (P < 0.00001) as well as in the GnRHa trigger group (P < 0.00001). The P4 ratio (the increase in P4 between ovulation induction and oocyte retrieval) was significantly higher in the group of patients with <5 follicles compared to those with 5-15 and >15 follicles (P < 0.0001). The FSH consumption per follicle was significantly higher in the group of patients with <5 follicles compared to those with 5-15 and >15 follicles (P < 0.0001).

LIMITATIONS, REASONS FOR CAUTION

Although the study demonstrates a significant correlation between P4 levels before and after ovulation trigger, it does not demonstrate a causal relation to the number of LHRs present on granulosa cells.

WIDER IMPLICATIONS OF THE FINDINGS

The findings of this study support the proposed hypothesis that follicles exposed to high levels of FSH during ovarian stimulation will respond with an inappropriately high LHR expression. This in turn causes a high P4 output in response to the trigger. This study further expands our understanding of the underlying mechanisms affecting reproductive outcomes in relation to ovarian stimulation.

STUDY FUNDING/COMPETING INTEREST(S)

The authors received no specific funding for this work and disclose no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Do we need to measure progesterone in oocyte donation cycles? A retrospective analysis evaluating cumulative live birth rates and embryo quality

STUDY QUESTION

Does late follicular-phase elevated serum progesterone (LFEP) during ovarian stimulation for oocyte donation have an impact on embryo quality (EQ) and cumulative live birth rate (CLBR)?

SUMMARY ANSWER

LFEP does not have an influence on EQ nor CLBR in oocyte donation cycles.

WHAT IS KNOWN ALREADY

Ovarian stimulation promotes the production of progesterone (P) which, when elevated during the follicular phase, has been demonstrated to have a deleterious effect in autologous fresh IVF outcomes. While there is robust evidence that this elevation results in impaired endometrial receptivity, the impact on EQ remains a matter of debate. The oocyte donation model is an excellent tool to assess the effects of LFEP on EQ from those on endometrium receptivity separately. Previous studies in oocyte donation cycles investigating the influence of elevated P on pregnancy outcomes in oocyte recipients showed conflicting results.

STUDY DESIGN, SIZE, DURATION

This is a retrospective analysis including all GnRH antagonist down-regulated cycles for fresh oocyte donation taking place in a tertiary referral university hospital between 2010 and 2017. A total of 397 fresh donor-recipient cycles were included. Each donor was included only once in the analysis and could be associated to a single recipient.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The sample was stratified according to serum P levels of ≤1.5 and &gt;1.5 ng/mL on the day of ovulation triggering. The primary endpoint of the study was the top-quality embryo rate on Day 3, and the secondary outcome measure was CLBR defined as a live-born delivery beyond 24 weeks.

MAIN RESULTS AND THE ROLE OF CHANCE

Three hundred ninety-seven fresh oocyte donation cycles were included in the analysis, of which 314 (79%) had a serum P ≤ 1.5 ng/mL and 83 (20.9%) had a serum P &gt; 1.5 ng/mL. The average age of the oocyte donors was 31.4 ± 4.7 and 29.9 ± 4.5 years, respectively, for normal and elevated P (P = 0.017). The mean number of oocytes retrieved was significantly higher in the elevated P group with 16.6 ± 10.6 vs 11.5 ± 6.9 in the P ≤ 1.5 group (P &lt; 0.001).

In parallel, the total number of embryos on Day 3, as well as the number of good-quality embryos at this stage, was significantly higher in the elevated P group (6.6 ± 5.6 vs 4.15 ± 3.5 and 8.7 ± 6.3 vs 6.1 ± 4.4; respectively, P &lt; 0.001). However, maturation and fertilization rates did not vary significantly between the two study groups and neither did the top- and good-quality embryo rate and the embryo utilization rate, all evaluated on Day 3 (P = 0.384, P = 0.405 and P = 0.645, respectively). A multivariable regression analysis accounting for P groups, age of the donor, number of retrieved oocytes and top-quality embryo rate as potential confounders showed that LFEP negatively influenced neither the top-quality embryo rate nor the CLBR.

LIMITATIONS, REASONS FOR CAUTION

This is an observational study based on a retrospective data analysis. Better extrapolation of the results could be validated by performing a prospective trial. Furthermore, this study was focused on oocyte donation cycles and hence the results cannot be generalized to the entire infertile population.

WIDER IMPLICATIONS OF THE FINDINGS

This is the first study providing evidence that LFEP does not influence CLBR and is adding strong evidence to the existing literature that LFEP does not harm EQ in oocyte donation programs.

STUDY FUNDING/COMPETING INTERESTS

Not applicable.

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.

Revisiting debates of premature luteinization and its effect on assisted reproductive technology outcome

The impact of the prematurely elevated serum progesterone on the late follicular phase, commonly known as premature luteinization (PL), is a matter of continuing debate. Available evidence supports that serum progesterone ≥ 1.5 ng/ml on the day of ovulation triggering could reduce the pregnancy potential in fresh in vitro fertilization (IVF) cycles by jeopardizing endometrial receptivity. Causes of PL during ovarian stimulation are unclear. Recent studies point toward the daily follicle-stimulating hormone dosage, duration of controlled ovarian stimulation, number of oocytes retrieved, and peak estradiol level as factors affecting the incidence of PL. Emerging data show additional influence on embryo quality. The prevention of PL has been challenging. The key elements in preventing PL include individualization of ovarian stimulation according to patient's ovarian reserve, proper ovulation trigger timing, and use of medications such as corticosteroids and metformin. Embryo cryopreservation with deferred embryo transfer is the established strategy to overcome PL, yet it is an extra burden to the IVF laboratory and increased cost for patients. Herein, we review the up-to-date knowledge of this frequent IVF problem including causes, proposed diagnostic criteria, and its impact on endometrial receptivity, embryo quality, and pregnancy outcomes. The preventive measures and rescue strategies are also discussed.

Lipid Profiling of Peri-implantation Endometrium in Patients With Premature Progesterone Rise in the Late Follicular Phase

CONTEXT

Late follicular phase elevation in serum progesterone (P) during controlled ovarian hyperstimulation negatively affects the outcome of assisted reproductive technology by contributing to endometrial-embryo asynchrony. There are still no data on lipid metabolite alterations during this process.

OBJECTIVES

To investigate alterations in the lipid profile during the window of implantation in patients with premature P rise.

DESIGN

Lipidomic variations in the endometrium were evaluated by ultrahigh-performance liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry.

SETTING

University assisted reproductive medicine unit.

PATIENTS OR OTHER PARTICIPANTS

Forty-three patients undergoing in vitro fertilization/intracytoplasmic sperm injection because of a tubal factor or male factor infertility were included in this study. The patients were divided into a high P group (P ≥ 1.5 ng/mL, 15 patients) and a normal P group (P < 1.5 ng/mL, 28 patients) on the day of human chorionic gonadotropin administration.

INTERVENTIONS

The endometrial tissues were obtained by Pipelle biopsy 7 days after human chorionic gonadotropin administration.

MAIN OUTCOME MEASURES

Alterations in lipid metabolites.

RESULTS

A total of 1026 ions were identified, and 25 lipids were significantly upregulated. The endometrial lipid profile was characterized by substantial increases in the concentrations of phosphatidylcholine, phosphatidylethanolamine, lysophosphatidylcholine, diacylglycerol, ceramide, phosphatidylinositol, and phosphatidylserine in patients with a premature P rise at the end of the follicular phase. The correlation analysis between P levels and lipids showed a stronger negative correlation between phosphatidylethanolamine or phosphatidylserine and P levels.

CONCLUSIONS

Premature P elevation disrupts the lipid homeostasis of the endometrium during the peri-implantation period. The altered lipid levels may impair endometrial receptivity and early embryo implantation.

Ovarian stimulation does not influence the uterine immune environment in healthy infertile women

RESEARCH QUESTION

There is some controversy regarding the impact of ovarian stimulation on immune cells in women undergoing IVF. The study's aim was to determine whether ovarian stimulation affected immune uterine cells in healthy women undergoing IVF.

DESIGN

This prospective cohort study included 28 patients undergoing IVF and 47 healthy oocyte donors. Endometrial biopsies were taken in a natural cycle and after ovarian stimulation. All participants had a normal karyotype, pelvic ultrasound and cervical cytology results and thyroid-stimulating hormone concentration, as well as normal glucose and insulin concentrations and inherited and acquired thrombophilia test results. Screening tests including human papillomavirus were normal. Immune cells were analysed using three techniques: fluorescence-activated cell sorting, immunohistochemistry and gene expression. A human leukocyte antigen (HLA)-C tetramer was used as an 'artificial embryo'. The expression of genes including those for tumour necrosis factor (TNF)-α and interleukin-10 (IL-10) was analysed.

RESULTS

A comparison was made of the percentage and gene expression of CD56^brightCD16^- uterine natural killer (uNK), CD56^dimCD16⁺ natural killer cells, CD56^-CD16⁺ natural killer cells and TregCD25⁺CD4⁺FoxP3⁺ cells, uNK binding to the HLA-C tetramer, and TNF-α and IL-10 expression. No between- or within-group differences were observed in natural versus ovarian stimulation cycles.

CONCLUSIONS

Ovarian stimulation does not affect the uterine immune cell population or HLA-C binding in healthy women undergoing ovarian stimulation. Further studies are underway to find out if different responses might be seen in women with previous autoimmune disorders.

Endometrium cytokine profiles are altered following ovarian stimulation but almost not in subsequent hormone replacement cycles

PURPOSE

To investigate the impact of ovarian stimulation and hormone replacement treatment on key regulatory cytokines in endometrial secretion during endometrium implantation window.

METHODS

Fifty-six patients undergoing ovarian stimulation (OS) with gonadotropin releasing hormone antagonist and frozen embryo transfer with hormone replacement treatment (HRT) were recruited. Endometrial secretion aspiration was performed repeatedly during implantation window in natural, OS and HRT cycles of every patient. The concentrations of 17 mediators, known to be involved in human embryo implantation, were assessed by multiplex immunoassay.

RESULTS

Compared with natural cycle (NC), the concentration of IFN-γ, G-CSF and IL-8 within endometrium were almost the same following OS and HRT. Furthermore, increased MCP-1 levels were observed following HRT and OS. In addition, an increase in IL-1b, IL-7, IL-17, IL-6, TNF-a, IL-12, IL-4, IL-13, IL-10, IL-5, VEGF and MIP-1b concentrations were found in OS cycle only. The level of GM-CSF was lower in HRT cycle and higher in OS cycle, when compared with NC. Among all 17 cytokines, no correlation was found between cytokine concentrations and serum estradiol and progesterone, while only IL-7 concentration has a low correlation with serum LH level.

CONCLUSION

Compared to natural and hormone replacement cycle, patients' endometrium cytokine profiles present an increased inflammatory response following ovarian stimulation.

High responders are not exempt from detrimental effects of prematurely rising progesterone levels in fresh embryo transfer cycles

RESEARCH QUESTION

Are high-responder IVF patients protected from the deleterious effect of prematurely elevated serum progesterone level on the probability of pregnancy?

DESIGN

In this retrospective cohort study, 2971 autologous fresh embryo transfer IVF cycles with gonadotrophin-releasing hormone agonist long protocol were analysed to investigate whether the detrimental effect of prematurely rising progesterone levels on clinical pregnancy rate (CPR) varies depending on the magnitude of ovarian response. Nine different evenly spaced intervals were constructed for serum progesterone level on the human chorionic gonadotrophin day (<0.5/0.5-0.9/1-1.4/1.5-1.9/2-2.4/2.5-2.9/3-3.4/3.5-3.9/>4 ng/ml). Then, IVF cycles in each of these intervals were further divided into low (≤3 oocytes), normal (4-15 oocytes) and high responders (≥16 oocytes).

RESULTS

The progressive rise of serum progesterone from the <0.5 to the >4 ng/ml interval caused a gradual and continuous decline in the CPR of all three types of ovarian response. The absolute difference in the CPR between the lowest and the highest progesterone groups was not related to the magnitude of ovarian response (-26.6%, -37.7% and -40.7% for the low, normal and high responders, respectively). On multivariate logistic regression analysis, the detrimental effect of progesterone started at 1.5-1.9 ng/ml, 3.0-3.4 ng/ml and 4.0-4.4 ng/ml intervals for the low, normal and high responders, respectively.

CONCLUSION

High responders are not exempt from the detrimental effects of prematurely rising serum progesterone levels but the threshold interval where the detrimental effect begins is higher in the high responders compared with the low and normal responders.

The curious case of premature luteinization

PURPOSE

Premature luteinization (PL) affects 12.3-46.7% of fresh in vitro fertilization cycles, and there is accumulating evidence confirming its negative effect on success rates. However, despite its clinical significance, PL is poorly understood and defined. This narrative review aims to provide a fresh look at the phenomenon of PL by summarizing the existing evidence and re-evaluating fundamental issues.

METHODS

A thorough electronic search was conducted covering the period from 1978 until January 2018 in PubMed, Embase, and Medline databases, and references of relevant studies were cross-checked. Meeting proceedings of the European Society of Human Reproduction and Embryology and the American Society for Reproductive Medicine were also hand searched.

RESULTS

In the curious case of PL, one should go back to the beginning and re-consider every step of the way. The pathogenesis, definition, measurement methods, clinical implications, and management strategies are discussed in detail, highlighting controversies and offering "food for thought" for future directions.

CONCLUSIONS

Authors need to speak the same language when studying PL in order to facilitate comparisons. The terminology, progesterone cut-off, measurement methods and days of measurement should be standardized and globally accepted; otherwise, there can be no scientific dialog. Future research should focus on specific patient profiles that may require a tailored approach. Progesterone measurements throughout the follicular phase possibly depict the progesterone exposure better than an isolated measurement on the day of hCG. Adequately powered randomized controlled trials should confirm which the best prevention and management plan of PL is, before introducing any strategy into clinical practice.

Oocyte-triggering day progesterone levels and endometrial appearance in normoresponders undergoing IVF/ICSI cycles: a hypothesis and a study protocol

In this report, we propose a study protocol capable of improving IVF outcomes in subfertile women with expected normal ovarian response. This proposal derives from conflicting published data and observations in our daily practice, concerning the negative impact of progesterone (P4) elevation at the day of oocyte triggering on pregnancy outcomes. Our hypothesis points to the combination of two previous "suspects" of reduced success after assisted reproduction techniques (ART) - the endometrium ultrasonographic parameters and P4 elevation at the day of oocyte triggering on their impact on pregnancy outcomes. Up-to-the minute data show that, there is a different impact of elevated P4 in fresh, frozen and donor cycles, whereas there are plenty of reports pointing to a different endometrial gene expression on different P4 measurements. Gaps in the literature are linked with a variation of the measurements of P4, its cycle-to-cycle reproducibility, the different cut-off levels used, the impact of various protocols of ovarian stimulation and the limitations of systematic reviews originating from the initial studies. Our hypothesis states that the combination of P4 values and endometrial ultrasound parameters at the day of oocyte triggering can affect clinical pregnancy rates in normal responders undergoing ART.