Ongoing pregnancy rates in single euploid frozen embryo transfers remain unaffected by female age: a retrospective study.

RESEARCH QUESTION: Is female age a significant factor in the likelihood of an ongoing pregnancy in single euploid frozen embryo transfers (FET)? DESIGN: Retrospective study of 1923 single euploid FET cycles in 1464 women, either in a natural cycle or a hormone replacement therapy cycle. The primary outcome was the ongoing pregnancy rate (OPR). RESULTS: There were 990 (51.48%) ongoing pregnancies among 1923 included transfers. The OPR were 51.4%, 49.1%, 53.3% and 52.3% for women aged ≤35, >35-≤37, >37-≤40 and >40 years at oocyte retrieval (OCR), without a significant trend for decreasing OPR (P = 0.679). No significant differences in female age at embryo transfer (P = 0.609) and female age at OCR (P = 0.816) were found between the groups (ongoing pregnancy versus no pregnancy or miscarriage). Women who received good-quality embryos (P < 0.001), had a lower body mass index (BMI) (P < 0.001), had achieved at least one pregnancy previously (P < 0.001), and underwent natural cycle endometrial preparation (P < 0.001) were more likely to achieve an ongoing pregnancy. Multivariable regression analysis (adjusted for BMI, embryo quality and endometrial preparation) did not show a significant effect of female age at OCR on achieving an ongoing pregnancy. Compared with women aged ≤35 years, none of the age groups had significantly higher or lower OPR. A multinomial regression analysis showed that BMI, embryo quality and endometrial preparation were associated with miscarriage/no pregnancy versus ongoing pregnancy (P = 0.001, 0.001 and 0.001, respectively). Female age had no significant association with either outcome. CONCLUSIONS: Female age in itself does not have a substantial impact on the OPR in single euploid FET cycles, but the OPR is impacted significantly by embryo quality, BMI, previous parity, and a natural cycle endometrial preparation protocol.

Do women with severely diminished ovarian reserve undergoing modified natural cycles benefit from earlier trigger at smaller follicle size?

OBJECTIVE: Would trigger and oocyte collection at smaller follicle sizes decrease the risk of premature ovulation while maintaining the reproductive potential of oocytes in women with severely diminished ovarian reserve in modified natural cycle IVF? METHODS: Retrospective cohort study including women who had at least one unsuccessful cycle (due to no response) of conventional ovarian stimulation with a high dosage of gonadotropins and subsequently underwent a modified natural cycle with a solitary growing follicle (i.e., only one follicle above >10mm at the time of trigger). The association between follicle size at trigger and various cycle outcomes was tested with regression analyses. RESULTS: A total of 160 cycles from 110 patients were included in the analysis. Oocyte pick-up (OPU) was performed in 153 cycles, 7 cycles were canceled due to premature ovulation. Patients who received their trigger shot at smaller follicle sizes (≤15mm) had significantly lower premature ovulation and thus higher OPU rates (98.3% vs. 94.0%, adjusted OR: 8.55, 95% CI: 1.30 - 172.2, P=0.048) compared to those who received it at larger follicle sizes (>15mm). In the multivariable analyses, smaller follicle sizes at trigger (>10 to ≤13mm, >13 to ≤15mm, >15mm to ≤17mm) were not significantly associated with a lower rate of cumulus-oocyte-complex (COC), metaphase II oocytes (MIIs), or blastulation compared to the >17mm group. In sensitivity analyses including the first cycle of each couple, the maturity rate among those with a COC retrieval was highest in follicle sizes >15 to ≤17mm (92.3%) and >13 to ≤15mm (91.7%), followed by >10 to ≤13mm (85.7%) and lowest in the >17mm group (58.8%). Five euploid blastocysts developed from 48 fertilized MIIs during the study period with follicle sizes at trigger 12mm (3), 14 mm (1), and 16mm (1). Four were transferred resulting in two live births, both developing from follicles with a size at trigger of 12mm. CONCLUSION: The ideal follicle size for triggering oocyte maturation may be smaller in women with severely diminished ovarian reserve managed on a modified natural cycle compared to conventional cut-offs. The risk of OPU cancellation was higher in women triggered above 15 mm, and the yield of mature oocytes was not adversely affected in women triggered at >13 to ≤15mm compared to >15mm to ≤17mm. Waiting for follicles to reach sizes above 17mm may be detrimental to achieving optimal outcomes. This article is protected by copyright. All rights reserved.

The combination of dydrogesterone and micronized vaginal progesterone can render serum progesterone level measurements on the day of embryo transfer and rescue attempts unnecessary in an HRT FET cycle.

PURPOSE: To evaluate the role of serum progesterone (P4) on the day of embryo transfer (ET) when dydrogesterone (DYD) and micronized vaginal progesterone (MVP) are combined as luteal phase support (LPS) in a hormone replacement therapy (HRT) frozen ET (FET) cycles. METHODS: Retrospective study, including single euploid HRT FET cycles with DYD and MVP as LPS and P4 measurement on ET day. Initially, patients with P4 levels < 10 ng/ml increased MVP to 400 mg/day; this "rescue" was abandoned later. RESULTS: 560 cycles of 507 couples were included. In 275 women, serum P4 level was < 10 ng/ml on the ET day. Among those with low P4 levels, MVP dose remained unchanged in 65 women (11.6%) and was increased in 210 women (37.5%). Women with P4 levels ≥ 10 ng/ml continued LPS without modification. Overall pregnancy rates in these groups were 61.5% (40/65), 54.8% (115/210), and 48.4% (138/285), respectively (p = n.s.). Association of serum P4 levels with ongoing pregnancy rates was analyzed in women without any additional MVP regardless of serum P4 levels (n = 350); multivariable analysis (adjusted for age, BMI, embryo quality (EQ)) did not show a significant association of serum P4 levels with OPR (OR 0.96, 95% CI 0.90-1.02; p = 0.185). Using inverse probability treatment weights, regression analysis in the weighted sample showed no significant association between P4 treatment groups and OP. Compared to fair EQ, the transfer of good EQ increased (OR 1.61, 95% CI 1.22-2.15; p = 0.001) and the transfer of a poor EQ decreased the odds of OP (OR 0.73, 95% CI 0.55-0.97; p = 0.029). CONCLUSION: In HRT FET cycle, using LPS with 300 mg/day MVP and 30 mg/day DYD, it appears that serum P4 measurement and increase of MVP in patients with P4 < 10 ng/ml are not necessary.

Are systemic progesterone levels in true natural cycle euploid frozen embryo transfers with luteal phase support predictive for ongoing pregnancy rates?

STUDY QUESTION: Are serum progesterone (P4) levels on the embryo transfer (ET) day predictive of ongoing pregnancy (OP) following a single euploid blastocyst transfer in a natural cycle (NC) when luteal phase support is routinely given? SUMMARY ANSWER: In single euploid frozen ETs in NC, P4 levels on ET day are not predictive for OP, when luteal phase support (LPS) is routinely added after the ET. WHAT IS KNOWN ALREADY: In an NC frozen embryo transfer (FET), P4 produced by the corpus luteum initiates secretory transformation of the endometrium and maintains pregnancy after implantation. There are ongoing controversies on the existence of a P4 cutoff level on the ET day, being predictive for the chance of OP as well as of the possible role of additional LPS after ET. Previous studies in NC FET cycles, evaluating and identifying P4 cutoff levels did not exclude embryo aneuploidy as a possible reason for failure. STUDY DESIGN, SIZE, DURATION: This retrospective study analyzed single, euploid FET in NC, conducted in a tertiary referral IVF centre between September 2019 and June 2022, for which measurement of P4 on the day of ET and the treatment outcomes were available. Patients were only included once into the analysis. Outcome was defined as OP (ongoing clinical pregnancy with heartbeat, >12 weeks) or no-OP (not pregnant, biochemical pregnancy, early miscarriage). PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients with an ovulatory cycle and a single euploid blastocyst in an NC FET cycle were included. Cycles were monitored by ultrasound and repeated measurement of serum LH, estradiol, and P4. LH surge was identified when a rise of 180% above the previous level occurred and P4 levels of ≥1.0 ng/ml were regarded as confirmation of ovulation. The ET was scheduled on the fifth day after P4 rise and vaginal micronized P4 was started on the day of ET after P4 measurement. MAIN RESULTS AND THE ROLE OF CHANCE: Of 266 patients included, 159 (59.8%) patients had an OP. There was no significant difference between the OP- and no-OP-groups for age, BMI, and day of embryo biopsy/cryopreservation (Day 5 versus Day 6). Furthermore, P4 levels were not different between the groups of patients with OP (P4: 14.8 ng/ml (IQR: 12.0-18.5 ng/ml)) versus no-OP (P4: 16.0 ng/ml (IQR: 11.6-18.9 ng/ml)) (P = 0.483), and no differences between both groups, when P4 levels were stratified into categories of P4 levels of >5 to ≤10, >10 to ≤15, >15 to ≤20, and >20 ng/ml (P = 0.341). However, both groups were significantly different for the embryo quality (EQ), defined by inner cell mass/trophectoderm, as well as when stratified into three EQ groups (good, fair, and poor) (P = 0.001 and 0.002, respectively). Stratified EQ groups remained the only significant parameter influencing OP in the uni- and multivariate analyses (P = 0.002 and P = 0.004, respectively), including age, BMI, and P4 levels (each in categories) and embryo cryopreservation day. Receiver operator characteristic curve for the prediction of an OP revealed an AUC of 0.648 when age, BMI and EQ groups were included into the model. The inclusion of P4 measurement on ET day into the model did not add any benefit for OP prediction (AUC = 0.665). LIMITATIONS, REASONS FOR CAUTION: The retrospective design is a limitation. WIDER IMPLICATIONS OF THE FINDINGS: Monitoring serum P4 levels can be abandoned in NC FET cycles with routine LPS as they do not seem to be predictive of live birth. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. The authors state that they do not have any conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

How to identify patients who would benefit from delayed-matured oocytes insemination: a sibling oocyte and ploidy outcome study.

STUDY QUESTION: Which patients might benefit from insemination of delayed-matured oocytes? SUMMARY ANSWER: Delayed-matured oocytes had a ≥50% contribution to the available cohort of biopsied blastocysts in patients with advanced maternal age, low maturation, and/or low fertilization rates. WHAT IS KNOWN ALREADY: Retrieved immature oocytes that progress to the MII stage in vitro could increase the number of embryos available during ICSI cycles. However, these delayed-matured oocytes are associated with lower fertilization rates and compromised embryo quality. Data on the ploidy of these embryos are controversial, but studies failed to compare euploidy rates of embryos derived from delayed-matured oocytes to patients' own immediate mature sibling oocytes. This strategy efficiently allows to identify the patient population that would benefit from this approach. STUDY DESIGN, SIZE, DURATION: This observational study was performed between January 2019 and June 2021 including a total of 5449 cumulus oocytes complexes from 469 ovarian stimulation cycles, from which 3455 inseminated matured oocytes from ICSI (n = 2911) and IVF (n = 544) were considered as the sibling controls (MII-D0) to the delayed-matured oocytes (MII-D1) (n = 910). Euploidy rates were assessed between delayed-matured (MII-D1) and mature sibling oocytes (MII-D0) in relation to patients' clinical characteristics such as BMI, AMH, age, sperm origin, and the laboratory outcomes, maturation, fertilization, and blastocyst utilization rates. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 390 patients undergoing IVF/ICSI, who had at least one metaphase I (MI) or germinal-vesicle (GV) oocyte on the day of oocyte collection (Day 0), which matured in 20-28 h after denudation were included. MI and GV oocytes that matured overnight were inseminated on the following day (Day 1, MII-D1) by ICSI. Only cycles planned for preimplantation genetic testing for aneuploidy using fresh own oocytes were included. MAIN RESULTS AND THE ROLE OF CHANCE: Fertilization (FR) and blastocyst utilization rates were significantly higher for MII-D0 compared to delayed-matured oocytes (MII-D1) (69.5% versus 55.9%, P < 0.001; and 59.5% versus 18.5%, P < 0.001, respectively). However, no significant difference was observed in the rate of euploid embryos between MII-D0 and MII-D1 (46.3% versus 39.0%, P = 0.163). For evaluation of the benefit of inseminating MI/GV oocytes on D1 per cycle in relation to the total number of biopsied embryos, cycles were split into three groups based on the proportion of MII-D1 embryos that were biopsied in that cycle (0%, 1-50%, and ≥50%). The results demonstrate that patients who had ≥50% contribution of delayed-matured oocytes to the available cohort of biopsied embryos were those of advanced maternal age (mean age 37.7 years), <10 oocytes retrieved presenting <34% maturation rate, and <60% fertilization rate. Every MII oocyte injected next day significantly increased the chances of obtaining a euploid embryo [odds ratio (OR) = 1.83, CI: 1.50-2.24, P < 0.001] among MII-D1. The odds of enhanced euploidy were slightly higher among the MII-D1-GV matured group (OR = 1.78, CI: 1.42-2.22, P < 0.001) than the MII-D1-MI matured group (OR = 1.54, CI: 1.25-1.89, P < 0.001). Inseminating at least eight MII-D1 would have >50% probability of getting a euploid embryo among the MII-D1 group. LIMITATIONS, REASONS FOR CAUTION: ICSI of MII-D1 was performed with the fresh or frozen ejaculates or testicular samples from the previous day. The exact timing of polar body extrusion of delayed-matured MI/GV was not identified. Furthermore, the time point of the final oocyte maturation to MII for the immature oocytes and for the oocytes inseminated by IVF could not be identified. WIDER IMPLICATIONS OF THE FINDINGS: The results of this study might provide guidance to the IVF laboratories for targeting the patient's population who would benefit from MII-D1 ICSI without adhering to unnecessary costs and workload. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received for this study. There are no conflicts of interest to be declared for any of the authors. There are no patents, products in development, or marketed products to declare. TRIAL REGISTRATION NUMBER: N/A.

Incidence and severity of ovarian hyperstimulation syndrome (OHSS) in high responders after gonadotropin-releasing hormone (GnRH) agonist trigger in "freeze-all" approach.

OBJECTIVE: To determine the incidence and severity of ovarian hyperstimulation syndrome (OHSS) in high responders (25-35 follicles with a diameter of ≥12 mm on day of triggering) who received a gonadotropin-releasing hormone (GnRH) agonist to trigger final follicular maturation. METHODS: We used individual data from women who participated in four different clinical trials and were high responders to ovarian stimulation in a GnRH antagonist protocol in this retrospective combined analysis. All women were evaluated for signs and symptoms of OHSS using identical criteria based on Golan's system (1989). RESULTS: High responders (n = 77) were of different ethnicities. There were no differences in baseline characteristics between women with or without signs and symptoms of OHSS. Mean ± standard deviation baseline data were: age, 32.3 ± 3.5 years; anti-Müllerian hormone, 42.4 ± 20.7 pmol/L; antral follicle count, 21.5 ± 9.2. Before triggering, duration of stimulation was 9.5 ± 1.6 days and the mean number of follicles with a diameter of ≥12 mm and ≥17 mm was 26.5 ± 4.4 and 8.8 ± 4.7, respectively. Mean serum estradiol (17,159 pmol/l) and progesterone (5.1 nmol/l) levels were high at 36 h after triggering. Overall, 17/77 high responders (22%) developed signs and symptoms of mild OHSS which lasted 6-21 days. The most frequently prescribed medication was cabergoline to prevent worsening of OHSS. No severe OHSS occurred and no OHSS cases were reported as serious adverse events. CONCLUSIONS: High responders receiving GnRH agonist for triggering should be informed that they may experience signs and symptoms of mild OHSS.

Sibling oocytes cultured in a time-lapse versus benchtop incubator: how time-lapse incubators improve blastocyst development and euploid rate.

The aim was to study whether a limited exposure of embryos outside the incubator has an effect on embryo development, blastocyst quality and euploid outcomes. This retrospective study was performed at ART Fertility Clinics, Abu Dhabi, United Arab Emirates (UAE) between March 2018 and April 2020 and included 796 mature sibling oocytes that were split randomly between two incubators after intracytoplasmic sperm injection (ICSI): an EmbryoScope™ (ES) incubator and a benchtop incubator, G185 K-SYSTEMS (KS). The fertilization, cleavage, embryo/blastocyst qualities, useable blastocyst and euploid rates were assessed to evaluate the incubator performance. In total, 503 (63.2%) mature oocytes were cultured in the EmbryoScope and 293 (36.8%) in the K-SYSTEMS. No differences were observed in fertilization rate (79.3% vs 78.8%, P = 0.932), cleavage rate (98.5% vs 99.1%, P = 0.676) and embryo quality on Day 3 (P = 0.543) between both incubators, respectively. Embryos cultured in the EmbryoScope, had a significantly higher chance of being biopsied (64.8% vs 49.6%, P < 0.001). Moreover, a significantly higher blastocyst biopsy rate was observed on Day 5 in the EmbryoScope (67.8% vs 57.0%, P = 0.037), with a highly significant increased euploid rate (63.5% vs 37.4%, P = 0.001) and improved blastocyst quality (P = 0.008). We found that exposure of embryos outside the incubator may negatively affect the in vitro blastocyst development and euploid rate on Day 5.

Antimüllerian hormone (AMH) and age as predictors of preimplantation genetic testing for aneuploidies (PGT-A) cycle outcomes and blastocyst quality on day 5 in women undergoing in vitro fertilization (IVF).

PURPOSE: The objective of this study was to investigate whether women with diminished ovarian reserve who planned for PGT-A exhibit a lower number of blastocysts for biopsy, ploidy outcomes, and blastocyst quality on day 5, regardless of age. METHODS: A retrospective analysis was performed between March 2017 and July 2020 at ART Fertility Clinics Abu Dhabi, including couples that were triggered for final oocyte maturation in an ovarian stimulated cycle planned for PGT-A. Patients were stratified into four AMH groups: < 0.65 ng/ml, 0.65-1.29 ng/ml, 1.3-6.25 ng/ml, and > 6.25 ng/ml; four age categories: ≤ 30, 31-35, 36-40, and > 40 years. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 1410 couples with a mean maternal age of 35.2 ± 6.4 years and AMH of 2.7 ± 2.6 ng/ml were included. In a multivariate logistic regression analysis, controlling for age, the chance of having at least one blastocyst biopsied/stimulated cycle (1156/1410), the chance of having at least one euploid blastocyst/stimulated cycle (880/1410), and the chance of having one euploid blastocyst once biopsy was performed (880/1156) were affected in all patients with AMH < 0.65 ng/ml [AdjOR 0.18[0.11-0.31] p = 0.008)], [AdjOR 0.18 [0.11-0.29] p < 0.001], and [AdjOR 0.34 [0.19-0.61] p = 0.015] as well as in patients with AMH 0.65-1.29 ng/ml (AdjOR 0.52 [0.32-0.84] p < 0.001), (AdjOR 0.49 [0.33-0.72] p < 0.001), and (AdjOR 0.57 [0.36-0.90] p < 0.001), respectively. In a multivariate linear regression analysis, AMH values did not affect blastocyst quality (- 0.72 [- 1.03 to - 0.41] p < 0.001). CONCLUSION: Irrespective of age, patients with diminished ovarian reserve (AMH < 1.3 ng/ml) have a lower chance of having at least one blastocyst biopsied and lower chance of having at least one euploid blastocyst per ovarian stimulated cycle. Blastocyst quality was not affected by AMH values.

The HERA (Hyper-response Risk Assessment) Delphi consensus definition of hyper-responders for in-vitro fertilization.

PURPOSE: To provide an agreed upon definition of hyper-response for women undergoing ovarian stimulation (OS)? METHODS: A literature search was performed regarding hyper-response to ovarian stimulation for assisted reproductive technology. A scientific committee consisting of 5 experts discussed, amended, and selected the final statements in the questionnaire for the first round of the Delphi consensus. The questionnaire was distributed to 31 experts, 22 of whom responded (with representation selected for global coverage), each anonymous to the others. A priori, it was decided that consensus would be reached when ≥ 66% of the participants agreed and ≤ 3 rounds would be used to obtain this consensus. RESULTS: 17/18 statements reached consensus. The most relevant are summarized here. (I) Definition of a hyper-response: Collection of ≥ 15 oocytes is characterized as a hyper-response (72.7% agreement). OHSS is not relevant for the definition of hyper-response if the number of collected oocytes is above a threshold (≥ 15) (77.3% agreement). The most important factor in defining a hyper-response during stimulation is the number of follicles ≥ 10 mm in mean diameter (86.4% agreement). (II) Risk factors for hyper-response: AMH values (95.5% agreement), AFC (95.5% agreement), patient's age (77.3% agreement) but not ovarian volume (72.7% agreement). In a patient without previous ovarian stimulation, the most important risk factor for a hyper-response is the antral follicular count (AFC) (68.2% agreement). In a patient without previous ovarian stimulation, when AMH and AFC are discordant, one suggesting a hyper-response and the other not, AFC is the more reliable marker (68.2% agreement). The lowest serum AMH value that would place one at risk for a hyper-response is ≥ 2 ng/ml (14.3 pmol/L) (72.7% agreement). The lowest AFC that would place one at risk for a hyper-response is ≥ 18 (81.8% agreement). Women with polycystic ovarian syndrome (PCOS) as per Rotterdam criteria are at a higher risk of hyper-response than women without PCOS with equivalent follicle counts and gonadotropin doses during ovarian stimulation for IVF (86.4% agreement). No consensus was reached regarding the number of growing follicles ≥ 10 mm that would define a hyper-response. CONCLUSION: The definition of hyper-response and its risk factors can be useful for harmonizing research, improving understanding of the subject, and tailoring patient care.

The HERA (Hyper-response Risk Assessment) Delphi consensus for the management of hyper-responders in in vitro fertilization.

PURPOSE: To provide agreed-upon guidelines on the management of a hyper-responsive patient undergoing ovarian stimulation (OS) METHODS: A literature search was performed regarding the management of hyper-response to OS for assisted reproductive technology. A scientific committee consisting of 4 experts discussed, amended, and selected the final statements. A priori, it was decided that consensus would be reached when ≥66% of the participants agreed, and ≤3 rounds would be used to obtain this consensus. A total of 28/31 experts responded (selected for global coverage), anonymous to each other. RESULTS: A total of 26/28 statements reached consensus. The most relevant are summarized here. The target number of oocytes to be collected in a stimulation cycle for IVF in an anticipated hyper-responder is 15-19 (89.3% consensus). For a potential hyper-responder, it is preferable to achieve a hyper-response and freeze all than aim for a fresh transfer (71.4% consensus). GnRH agonists should be avoided for pituitary suppression in anticipated hyper-responders performing IVF (96.4% consensus). The preferred starting dose in the first IVF stimulation cycle of an anticipated hyper-responder of average weight is 150 IU/day (82.1% consensus). ICoasting in order to decrease the risk of OHSS should not be used (89.7% consensus). Metformin should be added before/during ovarian stimulation to anticipated hyper-responders only if the patient has PCOS and is insulin resistant (82.1% consensus). In the case of a hyper-response, a dopaminergic agent should be used only if hCG will be used as a trigger (including dual/double trigger) with or without a fresh transfer (67.9% consensus). After using a GnRH agonist trigger due to a perceived risk of OHSS, luteal phase rescue with hCG and an attempt of a fresh transfer is discouraged regardless of the number of oocytes collected (72.4% consensus). The choice of the FET protocol is not influenced by the fact that the patient is a hyper-responder (82.8% consensus). In the cases of freeze all due to OHSS risk, a FET cycle can be performed in the immediate first menstrual cycle (92.9% consensus). CONCLUSION: These guidelines for the management of hyper-response can be useful for tailoring patient care and for harmonizing future research.

Are serum progesterone measurements truly representative for the identification of an adequate luteal phase in hormonal replacement therapy frozen embryo transfers?

ABSTRACT: Progesterone (P4) is crucial for the achievement and maintenance of a pregnancy and with rising numbers of frozen embryo transfers (FETs) performed worldwide, the search for the 'optimal' P4 levels in HRT FET cycles became a focus of research. Certainly, measurement of systemic P4 levels is an easy applicable tool and P4 levels, considered as being too low, could be addressed by changing and/or increasing exogenously administered P4. However, the question must be raised whether the sole measurement of systemic P4 levels is reflective for the endometrial status and the endometrial receptivity in HRT FET cycles, since systemic P4 levels do not reflect the dynamic of the endometrial changes, deemed necessary to prepare the endometrium for implantation. Moreover, different types of P4 administration routes will exhibit distinct different patterns of P4 release, affecting the process of secretory transformation and last but not least, embryonic factors are almost fully neglected in this concept. This opinion article aims to raise critical points towards the 'sole' focus on systemic P4 levels in HRT FET cycles and raises the question whether 'serum P4 measurements are truly representative for the identification of an adequate luteal phase in HRT FETs'?.

The Prognosis and Predictive Value of Estrogen Negative/Progesterone Positive (ER-/PR+) Phenotype: Experience of 1159 Primary Breast Cancer from a Single Institute.

Breast cancer is a serious worldwide public health problem and is currently the most common cancer overall. Its endocrine therapy is related to the expression of the steroid hormones, estrogen receptor (ER), and progesterone receptor (PR). Breast cancers can be presented under multiple profiles of steroid hormones: ER(-)/PR(+), ER(+)/PR(-), double-positive/negative ER, and PR. 2-8% of all breast cancers express only PR (ER-/PR+) which is an abnormal phenotype, with less known about their behaviors and outcomes. Our study was performed on a large and well-characterized database of primary breast cancer from 2012 to 2019, up to 1159 cases. These cases were divided according to ER and PR expression, as we put all of our focus on ER-negative/PR-positive group, more specifically ER-/PR+/HER2+ and ER-/PR+/HER2- gene expressions, to highlight their features and find a pattern that links HR (hormone receptors) profiles and breast cancer subtypes. Out of the informative cases, 94 patients (8%) had ER-/PR+ breast cancers, while 676 (58.4%) had ER+/PR+, 88 (7.6%) had ER+/PR-, and 164 (14.2%) had ER-/PR- tumors. The ER-/PR+ group was statistically correlated with a high risk of recurrence and death in midway between the double-negative and double-positive HR. According to HER2 status, a low DFS was observed in patients ER-/PR+/HER2-, which is closer to the DFS of TNBC cases but worse than ER+/PR any. On the other side, the ER-/PR+/HER2+ showed also a poorer DFS closer to the HER2+ subgroup in between TNBC and ER+/PR any. The clinicopathological features of the ER-/PR+/HER2- and ER-/PR+ HER2+ have distinguished the patients into two groups with a difference in some clinicopathological characteristics: both groups had closer OS estimation, which was worse than ER-/PR any and better than TNBC and HER2. The ER-/PR+/HER2- seems to increase the risk of recurrence than ER-/PR+/HER2+ when compared to ER+/PR any. On the other hand, the ER-/PR+/HER2+ seems to increase the risk of death more than ER-/PR+/HER2- in comparison with ER+/PR any. Our results support that ER-/PR+ tumors really exist and are rare and clinically and biologically distinct subtypes of breast cancer. In addition, our analysis, which was based on dividing the groups according to HER2 expression, has revealed the existence of two distinct groups; this gave the ER-/PR+ subgroup a heterogeneity characterization. Moreover, this breast cancer subtype should not be treated as a luminal tumor but rather according to the HER2 expression status.

Evolution of serum progesterone levels in the very early luteal phase of stimulated IVF/ICSI cycles post hCG trigger: a proof of concept study.

BACKGROUND: Studies have suggested that controlled ovarian hyperstimulation adversely affects endometrial receptivity due to advanced endometrial maturation. This adverse effect is mainly attributed to supraphysiological levels of both estrogen and progesterone identified in stimulated cycles. There is a paucity of published data investigating the very early luteal steroid profile following hCG trigger. AIM OF THE STUDY: This prospective, observational study was undertaken to determine the increase in serum progesterone levels after human chorionic gonadotrophin (hCG) trigger in stimulated IVF/ICSI cycles. MATERIALS AND METHODS: This proof-of-concept study included 11 patients requiring ovarian stimulation for IVF/ICSI and who planned to avail of pre-implantation genetic screening with embryo vitrification of their biopsied embryos at blastocyst stage. For each study participant, five additional blood samples were drawn at the following specific times in the stimulation cycle, on the morning (10.00-12.00) of the assigned day to induce final oocyte maturation with hCG trigger, immediately prior to administration of hCG for final oocyte maturation, 1 h, 2 h, and 36 h post hCG trigger. A prediction model, the Gompertz curve, was used to determine serum progesterone levels at intervals between the 2 h post hCG trigger sample and the day of oocyte retrieval. RESULTS: Statistically significant increases in serum progesterone levels were identified following hCG administration as early as 1 h following trigger (P4 0.57 ng/ml, p < 0.05), 2 h following trigger (P4 0.88 ng/ml, p < 0.001) and on the day of oocyte retrieval (P4 9.68 ng/ml, p < 0.001). According to our prediction model, the Gompertz curve, the projected serum progesterone level at 4 h post trigger would have achieved a level of 1.45 ng/ml, 8 h post trigger of 3.04 ng/ml, and 12 h post trigger of 4.8 ng/ml. The very early and significant increases in serum progesterone following hCG trigger are clearly demonstrated in this study. CONCLUSION: The endometrium is undoubtedly exposed to rapidly increasing serum progesterone levels post hCG trigger that would not be identified until much later in natural menstrual cycles. TRIAL REGISTRATION NUMBER: This study is registered with clinicaltrials.gov under the identifier NCT04417569.

The clinicians´ dilemma with mosaicism-an insight from inner cell mass biopsies.

STUDY QUESTION: How reliable are cleavage stage and trophectoderm (TE) biopsies compared to inner cell mass (ICM) biopsies? SUMMARY ANSWER: The reliability of TE biopsy compared to ICM biopsy is almost perfect, but only substantial between cleavage stage biopsy and ICM biopsy. WHAT IS KNOWN ALREADY: One of the prevailing reasons for implantation failure is presumed to be chromosomal aneuploidy in human preimplantation embryos. Preimplantation genetic testing for aneuploidies (PGT-A) has been introduced into assisted reproduction in an effort to increase pregnancy rates. Increasing evidence indicates that genetic results obtained following blastomere or TEbiopsy may not accurately reflect the true genetic status of the embryo due to the presence of embryonic mosaicism, and therefore the reliability of PGT is highly controversial. STUDY DESIGN, SIZE, DURATION: This was an observational descriptive study, performed in a private infertility centre from August 2016 to January 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: The mean female age was 33.9 years, ranging from 24 to 46 years, and the mean number of biopsied embryos per couple was 2.2 (range 1-7 embryos). Blastomere biopsies had been performed at cleavage stage on Day 3 (D3) due to the turnover time of genetic testing and the inability to cryopreserve embryos in accordance with the local law governing ART. To confirm the genetic results in embryos not chosen for transfer, additional biopsies of the TE at blastocyst stage (BLASTO-TE) as well as of the ICM (BLASTO-ICM) were performed on D5. Only surplus blastocysts, which had not been selected for transfer and were not cryopreserved in accordance with the law governing ART, had been included. MAIN RESULTS AND THE ROLE OF CHANCE: Comparison of all biopsies (D3/BLASTO-ICM/BLASTO-TE) per embryo demonstrated that 50 (59.5%) out of 84 embryos showed concordance in all three results (= full concordance). Thirty-four (40.4%) embryos had at least two discordant results between the three biopsies, regardless of whether the embryo diagnosis (aneuploid/euploid) was discordant or not, or in aneuploid embryos, whether the chromosomal patterns were inconsistent. Nine (= 10.7%) embryos had complete discordance between all three biopsies. False positive results between D3/BLASTO-TE, D3/BLASTO-ICM and BLASTO-TE/BLASTO-ICM were 26.4%/30.2% and 7.5%, respectively, while the Kappa agreement between the different approaches was 0.647, 0.553 and 0.857, respectively. Therefore the reliability of D3/BLASTO-TE, D3/BLASTO-ICM and BLASTO-TE/BLASTO-ICM can be interpreted as substantial, as moderate and as almost perfect. LIMITATIONS, REASONS FOR CAUTION: The limitation of this study is the possible bias in the concordance/discordance rate because embryos that had been selected for transfer did not undergo biopsy on D5. WIDER IMPLICATIONS OF THE FINDINGS: The obvious discordance between the three different approaches for PGT-A underlines the limitations of genetic testing and highlights the importance of ongoing research in order to improve the accuracy of PGT-A results. Until then reproductive specialists will continue to make challenging decisions on whether to transfer or discard an embryo in light of current evidence questioning the reliability of genetic results. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by Igenomix. The funder provided support in the form of salary for R.C. The co-author R.C. is an employee of Igenomix. She participated in the blinded analysis of the samples; however the final data collection and statistical analysis of the results, as well as the decision to publish, was taken by B.L, I.E. and H.F. The authors B.L., I.E., A.L., A.B., A.A., N.D. and H.F. have no competing interests. The funder did not have any additional role in the study design, data collection and analysis, decision to publish or preparation of the manuscript. The commercial affiliation of R.C. did not play any role in the study. TRIAL REGISTRATION NUMBER: This study was approved by the Ethics Committee of IVIRMA Middle East Fertility Clinic, Abu Dhabi, UAE (Research Ethics Committee IVI-MEREFA009a/2017).

Luteal phase serum progesterone levels after GnRH-agonist trigger - how low is still high enough for an ongoing pregnancy?

In the past years, individualization of assisted reproductive technique (ART)-treatment is increasingly common to customize the treatment protocol to the patient's specific conditions. The use of GnRH-agonist for final oocyte maturation in a gonadotropin-releasing hormone (GnRH)-antagonist protocol is the best approach to reduce the risk for ovarian hyperstimulation in high responder patients. However, due to severe luteolysis, the reproductive outcome with this approach in combination with the use of vaginal progesterone as luteal phase support, was poor. Cycle segmentation as alternative to a fresh transfer requires embryo freezing which might not be applicable to all patients due to various reasons. The concept of luteal coasting monitors the progesterone-level closely and human chorionic gonadotropin (hCG) for rescue of the corpora lutea is administered when the progesterone-level drops below a certain threshold. However, the lower range of progesterone levels in the early luteal phase after GnRH-agonist trigger, which is compatible with achieving and maintaining a pregnancy, is unknown. This case-series demonstrates, that ongoing pregnancies can be achieved even with a progesterone-level below 15 ng/ml in the early luteal phase with the timely administration of an hCG-rescue bolus. With the concept of luteal coasting, individualization of the luteal phase support according to the patient's specific luteolysis pattern is possible.

Effect of progesterone elevation in follicular phase of IVF-cycles on the endometrial receptivity.

The premature rise of progesterone during the late follicular phase in stimulated IVF cycles is a frequent event, and emerging evidence shows that premature progesterone rise does negatively affect the outcome of assisted reproductive techniques. The effect of elevated peripheral progesterone levels in the late follicular phase seems to be on the endometrium and the window of implantation, which may lead to asynchrony between the endometrium and the developing embryo. In stimulated cycles, endometrial maturation is advanced on the day of oocyte retrieval, and patients with a progesterone level above 1.5 ng/ml on the day of final oocyte maturation have different endometrial gene expression profiles. This progesterone level seems to represent the critical threshold, at which a negative effect on the ongoing pregnancy rate in fresh IVF cycles can be observed. Moreover, no association exists between progesterone elevation in the fresh cycle, and the probability of pregnancy after transfer of frozen-thawed embryos, originating from that cycle. The causes of premature progesterone elevation during ovarian stimulation are still unclear; however, recent studies point towards enhanced FSH-stimulation as a cause for progesterone elevation.

Individual luteolysis post GnRH-agonist-trigger in GnRH-antagonist protocols.

Over the past few years, the use of Gonadotropin-releasing-hormone (GnRH)-agonist for final oocyte maturation in GnRH-antagonist-protocols in stimulated IVF/ICSI cycles has gained worldwide acceptance, as this approach reduces significantly the risk for development of ovarian hyperstimulation syndrome (OHSS). Final oocyte maturation with GnRH-agonist leads to sever luteolysis, which cannot be counterbalanced using standard luteal phase support with purely progesterone (P4) application and therefore administration of hCG or high doses of P4 is considered to be essential to prevent/counteract luteolysis. However, lately publications indicate, that luteolysis is not always complete after GnRH-agonist for trigger. This case-series evaluates the degree of luteolysis in high-responder-patients, who received GnRH-agonist for final oocyte maturation. Assessment of estradiol (E2)- and P4-levels 48 h after oocyte-pick-up (OPU) procedure demonstrate clearly, that luteolysis after GnRH-agonist trigger is individual-specific, even in high-responder patients with the same number of oocytes. Hence, individualization of luteal phase support with the focus on avoiding unnecessary administration of hCG, bearing the risk for development of OHSS, a new concept of luteal coasting needs to be developed, based on severity of luteolysis following luteal coasting.

Impact of gonadotropin type on progesterone elevation during ovarian stimulation in GnRH antagonist cycles.

STUDY QUESTION: Does hormonal stimulation with corifollitropin alpha (CFA) only, mimicking a step down protocol, result in lower incidence of progesterone elevation on the day of hCGtrigger as compared to sustained stimulation with recombinant FSH (rFSH)? SUMMARY ANSWER: The current findings support the concept that sustained FSH stimulus contributes to premature progesterone elevation in stimulated IVF cycles. WHAT IS KNOWN ALREADY: Serum progesterone rise during the follicular phase of ovarian stimulation for IVF treatment seems to be related to a poorer reproductive outcome. However, the mechanism by which the rise in progesterone is caused is not yet fully understood. STUDY DESIGN, SIZE, DURATION: This study was a post hoc analysis of data from two multi-center, randomized, double-blind, double-dummy, active-controlled, non-inferiority trials, ENGAGE and PURSUE, conducted from June 2006 to January 2008 and from July 2010 to October 2012 respectively. PARTICIPANTS/MATERIALS, SETTING, METHODS: In the ENGAGE-study, 1506 women, aged 18-36 years, were allocated to either a single injection of 150 mg CFA or daily injections of 200 IU rFSH in the first week of stimulation, using a standard GnRH antagonist protocol. In the PURSUE-study, a total of 1390 women, aged 35-42 years, were allocated to either a single injection of 150 mg of CFA or daily 300 IU of rFSH for the first week, again using a standard GnRH antagonist protocol. In both trials, daily rFSH was continued until three follicles reached >17 mm in size. All women had a body weight of between 50 and 90 kg, regular menstrual cycles and an indication for ovarian stimulation before IVF. The incidence of progesterone elevation on day of hCG-trigger in patients with CFA only or rFSH stimulation, and triggered on Day 8 of stimulation, was analyzed. MAIN RESULTS AND THE ROLE OF CHANCE: Of patients with CFA only stimulation, 5.4% (13/239 patients) showed a progesterone elevation above 1.5 ng/ml on day of hCG-trigger, whereas patients with rFSH stimulation had a significant higher incidence of progesterone elevation (18.3%; 62/339 patients) (P < 0.001). LIMITATIONS, REASONS FOR CAUTION: Post hoc analysis of data from previously published trials could be considered as a reason for caution. WIDER IMPLICATIONS OF THE FINDINGS: Future studies should evaluate whether it would be possible to prevent a premature progesterone rise in cycles stimulated with daily FSH by using a step down protocol towards the end of the follicular phase. STUDY FUNDING/COMPETING INTERESTS: Financial/Material Support was provided by Merck & Co., Inc., Kenilworth, NJ, USA. Davis Gates is an employee of Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA and may own stock and/or hold stock options in the company. Fabiola Beligotti is an employee of MSD, Italy, a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA and may own stock and/or hold stock options in the company. Barbara Lawrenz, Nils Engelmann and Human M. Fatemi have no conflict of interest. TRIAL REGISTRATION NUMBER: ENGAGE study: ClinicalTrials.gov identifier NTC00696800. PURSUE-study: NCT01144416.