Presence of Adenomyosis Impairs Clinical Outcomes in Women Undergoing Frozen Embryo Transfer: A Retrospective Cohort Study.

(1) Background: The presence of adenomyosis among pregnant patients has been associated with a higher incidence of miscarriage and pregnancy complications. Although the role of adenomyosis in women undergoing in vitro fertilization (IVF) was investigated in several studies and demonstrated a potentially detrimental effect on live birth rates following IVF, most of them were small studies in which the adenomyosis diagnosis was not confirmed based on solid ultrasonographic criteria. (2) Methods: 3503 patients undergoing their first blastocyst frozen transfer through a hormonal replacement (HRT) FET cycle. Among them, 140 women had a confirmed diagnosis of adenomyosis based on the MUSA criteria. (3) Results: Adenomyosis patients were more likely to proceed with deferred FET compared with no-adenomyosis women (p = 0.002) and were significantly more likely to be treated with GnRH agonist pre-treatment (2 months) (p < 0.001). The presence of adenomyosis significantly decreased the clinical pregnancy rates (aOR 0.62, 95% CI: 0.39-0.98, p = 0.040) and live birth rates (aOR 0.46, 95% CI: 0.27-0.75, p = 0.003) and significantly increased the miscarriage rates (aOR 2.13, 95% CI: 0.98-4.37, p = 0.045). Multivariable logistic regression adjusting for age, autologous or donor oocytes, PGT-A, deferred FET, serum progesterone levels the day before FET, GnRH agonist pre-treatment, number of embryos transferred, and adenomyosis demonstrated that the use of the GnRH agonist protocol did not decrease or increase the miscarriage rate, clinical pregnancy rate, or live birth rate. (4) Conclusions: The presence of adenomyosis had a significant negative impact on the clinical outcomes of patients undergoing FET and was associated with higher miscarriage, lower clinical pregnancy, and live birth rates. GnRH agonist pre-treatment does not appear to improve clinical outcomes.

Elevated serum progesterone levels before frozen embryo transfer do not negatively impact reproductive outcomes: a large retrospective cohort study.

OBJECTIVE: To evaluate whether patients with high-serum progesterone levels before frozen embryo transfer (FET) under hormonal replacement therapy present with worse reproductive outcomes. DESIGN: A cohort retrospective study. SETTING: A university-affiliated fertility center. PATIENT(S): A total of 3,183 FET cycles in patients receiving hormonal replacement therapy between March 2009 and December 2020 were included. The luteal phase was covered with 200 mg per 8 hours of vaginal micronized progesterone either alone or in combination with a daily subcutaneous injection of 25 mg of progesterone. A total of 1,360 cycles corresponded to frozen homologous embryo transfer (ET) (hom-FET), 1,024 were euploid ET (eu-FET) after preimplantation genetic testing for aneuploidies, and 799 cycles were frozen heterologous ET (het-FET). All patients had adequate serum progesterone levels (≥10.6 ng/mL) before the procedure. INTERVENTION(S): Frozen embryo transfer cycles. MAIN OUTCOME MEASURE(S): Clinical pregnancy, miscarriage, and live birth rates (LBRs). RESULTS: Median (P25; P75) serum progesterone level before FET was 14.39 (12.43-17.49) ng/mL. Progesterone levels were significantly higher in the group under vaginal plus subcutaneous progesterone (15.96 [13.74-21.60] vs. 14.09 [12.19-16.95]). No differences in clinical pregnancy, miscarriage, and LBR were observed based on the use of vaginal or vaginal plus subcutaneous progesterone for each of the groups (hom-FET, eu-FET, and het-FET). Live birth rates were comparable among patients in the highest centile of serum progesterone levels (≥p90) (22.33 ng/mL) and the rest of the patients (p<90) (43.9% vs. 41.3%). Patients with progesterone levels ≥p90 presented lower body mass index than those in the lower centiles (

Do reproductive history and information given through genetic counselling influence patients' decisions on mosaic embryo transfer?

OBJECTIVE: To assess patients' and embryonic characteristics that may have an influence on the decision to transfer a mosaic embryo. METHOD: Single centre retrospective cohort study including 1247 PGT-A cycles. Demographic and clinical factors associated with a decision to transfer a mosaic embryo were studied. Female age, number of previous cycles, previous availability of euploid embryos, history of miscarriages and parity as well as percentage of mosaicism, type of anomaly and chromosome risk were studied in relation to decision-making. Outcomes after mosaic embryo transfer were assessed. RESULTS: To date, in 7.9% of cycles (99/1247), patients have had to make a decision on the fate of their mosaic embryos. In 23.2% of cycles (23/99), patients decided to transfer. In most cases (79.8%; 79/99), patients underwent genetic counselling before the decision. None of the variables analysed were associated with the patients' decision, although parity and the high-degree mosaicism (>50%) seemed to be negatively associated with the decision to transfer (18.2% vs. 29.8%, p = 0.294; 10% vs. 32.2%, p = 0.052). CONCLUSIONS: Neither reproductive history nor information on mosaic embryo characteristics through counselling seems to be determinative for patients when deciding to transfer a mosaic embryo. Promising and increasing data on clinical outcomes after mosaic embryo transfer will be of utmost importance to soften risk perception regarding mosaic embryos and give a better, simplified and more evidence-based counselling.

The effect of trophectoderm biopsy technique and sample handling on artefactual mosaicism.

PURPOSE: To determine whether embryo mosaicism prevalence in preimplantation genetic testing for aneuploidy (PGT-A) cycles is associated with the trophectoderm biopsy technique used (a. number of laser pulses or b. the use of flicking or pulling) or the time to tubing. METHODS: Prospective observational study performed in a single IVF-PGT-A setting from May 2019 to May 2021. Trophectoderm biopsies were analysed by next-generation sequencing. Mosaicism was analysed in relation to the biopsy methodology (number of laser pulses and pulling vs flicking), time elapsed from biopsy to tubing (min), and time of sample cryostorage from tubing to amplification (days). As a secondary objective, the number of laser pulses and biopsy methodology were studied in relation to clinical outcomes of transferred euploid blastocysts. RESULTS: None of the analysed variables were associated to mosaicism prevalence. Multivariable regression analysis demonstrated that mosaicism prevalence was comparable either when  > 3 laser pulses were used as compared to ≤ 3 (13.9% vs 13.8%, aOR = 0.8726 [0.60-1.28]) and pulling compared to flicking (13.1% vs 14.0%, aOR = 0.86 [0.60-1.23]). Moreover, neither the number of laser pulses during biopsy (> 3 vs ≤ 3) nor the technique used (pulling vs flicking) were associated with clinical pregnancy after the transfer of frozen-thawed euploid blastocysts (54.9% vs 55.2%, aOR = 1.05 [0.53-2.09]; 61.1% vs 52.9%, aOR = 1.11 [0.55-2.25], respectively). CONCLUSION: Our results suggest that, as long as the biopsy and tubing procedures are performed following standardized high quality procedures, no specific approach would increase the generation of artefactual mosaicism as a result of trophectoderm biopsy. Trophectoderm biopsies should be performed regardless of the methodology but always aiming on minimising blastocyst manipulation.

The effect of short term exposure to outdoor air pollution on fertility.

BACKGROUND: There is evidence to suggest that long term exposure to air pollution could be associated with decreased levels of fertility, although there is controversy as to how short term exposure may compromise fertility in IVF patients and what windows of exposure during the IVF process patients could be most vulnerable. METHODS: This prospective cohort study aimed to evaluate the impact of acute exposure that air pollution have on reproductive outcomes in different moments of the IVF process. Women undergoing IVF living in Barcelona were recruited. Individual air pollution exposures were modelled at their home address 15 and 3 days before embryo transfer (15D and 3D, respectively), the same day of transfer (D0), and 7 days after (D7). The pollutants modelled were: PM2.5 [particulate matter (PM) ≤2.5 µm], PMcoarse (PM between 2.5 and 10µm), PM10 (PM≤10 µm), PM2.5 abs, and NO2 and NOx. Outcomes were analyzed using multi-level regression models, with adjustment for co-pollutants and confouding factors. Two sensitivity analyses were performed. First, the model was adjusted for subacute exposure (received 15 days before ET). The second analysis was based on the first transfer performed on each patient aiming to exclude patients who failed previous transfers. RESULTS: One hundred ninety-four women were recruited, contributing with data for 486 embryo transfers. Acute and subacute exposure to PMs showed a tendency in increasing miscarriage rate and reducing clinical pregnancy rate, although results were not statistically significant. The first sensitivity analysis, showed a significant risk of miscarriage for PM2.5 exposure on 3D after adjusting for subacute exposure, and an increased risk of achieving no pregnancy for PM2.5, PMcoarse and PM10 on 3D. The second sensitivity analysis showed a significant risk of miscarriage for PM2.5 exposure on 3D, and a significant risk of achieving no pregnancy for PM2.5, PMcoarse and PM10 particularly on 3D. No association was observed for nitrogen dioxides on reproductive outcomes. CONCLUSIONS: Exposure to particulate matter has a negative impact on reproductive outcomes in IVF patients. Subacute exposure seems to increase the harmful effect of the acute exposure on miscarriage and pregnancy rates. Nitrogen dioxides do not modify significantly the reproductive success.

Individualised luteal phase support in artificially prepared frozen embryo transfer cycles based on serum progesterone levels: a prospective cohort study.

STUDY QUESTION: Does an individualised luteal phase support (iLPS), according to serum progesterone (P4) level the day prior to euploid frozen embryo transfer (FET), improve pregnancy outcomes when started on the day previous to embryo transfer? SUMMARY ANSWER: Patients with low serum P4 the day prior to euploid FET can benefit from the addition of daily subcutaneous P4 injections (Psc), when started the day prior to FET, and achieve similar reproductive outcomes compared to those with initial adequate P4 levels. WHAT IS KNOWN ALREADY: The ratio between FET/IVF has spectacularly increased in the last years mainly thanks to the pursuit of an ovarian hyperstimulation syndrome free clinic and the development of preimplantation genetic testing (PGT). There is currently a big concern regarding the endometrial preparation for FET, especially in relation to serum P4 levels around the time of embryo transfer. Several studies have described impaired pregnancy outcomes in those patients with low P4 levels around the time of FET, considering 10 ng/ml as one of the most accepted reference values. To date, no prospective study has been designed to compare the reproductive outcomes between patients with adequate P4 the day previous to euploid FET and those with low, but restored P4 levels on the transfer day after iLPS through daily Psc started on the day previous to FET. STUDY DESIGN, SIZE, DURATION: A prospective observational study was conducted at a university-affiliated fertility centre between November 2018 and January 2020 in patients undergoing PGT for aneuploidies (PGT-A) IVF cycles and a subsequent FET under hormone replacement treatment (HRT). A total of 574 cycles (453 patients) were analysed: 348 cycles (leading to 342 euploid FET) with adequate P4 on the day previous to FET, and 226 cycles (leading to 220 euploid FET) under iLPS after low P4 on the previous day to FET, but restored P4 levels on the transfer day. PARTICIPANTS/MATERIALS, SETTING, METHODS: Overall we included 574 HRT FET cycles (453 patients). Standard HRT was used for endometrial preparation. P4 levels were measured the day previous to euploid FET. P4 > 10.6 ng/ml was considered as adequate and euploid FET was performed on the following day (FET Group 1). P4 < 10.6 ng/ml was considered as low, iLPS was added in the form of daily Psc injections, and a new P4 analysis was performed on the following day. FET was only performed on the same day when a restored P4 > 10.6 ng/ml was achieved (98.2% of cases) (FET Group 2). MAIN RESULTS AND THE ROLE OF CHANCE: Patient's demographics and cycle parameters were comparable between both euploid FET groups (FET Group 1 and FET Group 2) in terms of age, weight, oestradiol and P4 levels and number of embryos transferred. No statistically significant differences were found in terms of clinical pregnancy rate (56.4% vs 59.1%: rate difference (RD) -2.7%, 95% CI [-11.4; 6.0]), ongoing pregnancy rate (49.4% vs 53.6%: RD -4.2%, 95% CI [-13.1; 4.7]) or live birth rate (49.1% vs 52.3%: RD -3.2%, 95% CI [-12; 5.7]). No significant differences were also found according to miscarriage rate (12.4% vs 9.2%: RD 3.2%, 95% CI [-4.3; 10.7]). LIMITATIONS, REASONS FOR CAUTION: Only iLPS through daily Psc was evaluated. The time for Psc injection was not stated and no serum P4 determinations were performed once the pregnancy was achieved. WIDER IMPLICATIONS OF THE FINDINGS: Our study provides information regarding an 'opportunity window' for improved ongoing pregnancy rates and miscarriage rates through a daily Psc injection in cases of inadequate P4 levels the day previous to FET (P4 < 10.6 ng/ml) and restored values the day of FET (P4 > 10.6 ng/ml). Only euploid FET under HRT were considered, avoiding one of the main reasons of miscarriage and implantation failure and overcoming confounding factors such as female age, embryo quality or ovarian stimulation protocols. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received. B.C. reports personal fees from MSD, Merck Serono, Ferring Pharmaceuticals, IBSA and Gedeon Richter outside the submitted work. N.P. reports grants and personal fees from MSD, Merck Serono, Ferring Pharmaceuticals, Theramex and Besins International and personal fees from IBSA and Gedeon Richter outside the submitted work. The remaining authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: NCT03740568.

Prevalence, types and possible factors influencing mosaicism in IVF blastocysts: results from a single setting.

RESEARCH QUESTION: Are intrinsic or extrinsic factors associated with embryo mosaicism prevalence in IVF cycles? DESIGN: Retrospective cohort study of preimplantation genetic testing for aneuploidy (PGT-A) cycles carried out at a university-affiliated IVF clinic between October 2017 and October 2019. Trophectoderm biopsies were analysed by next generation sequencing. Mosaicism prevalence, type of anomaly and the chromosomes involved were analysed. Intrinsic and extrinsic factors potentially inducing mosaicism were studied: maternal and paternal age, antral follicle count, cumulus-oocyte complexes retrieved, female body mass index, PGT-A indication, sperm concentration, total dosage of gonadotrophins, embryo quality and day of blastocyst formation, single-step commercial media used and biopsy operator. RESULTS: Overall prevalence of mosaicism in our PGT-A setting was 13.9%. In segmental mosaicism, larger chromosomes tended to be more affected, which was not observed in whole-chromosome mosaicism. Additionally, segmental mosaicism was mostly observed in monosomy (69.6%; P < 0.01) compared with whole-chromosome mosaicism (49.7% monosomies versus 50.3% trisomies; P = 0.83). Although a high inter-patient variability was observed, only paternal age showed a positive association with mosaicism (adjusted OR 1.26, 95% CI 1.02 to 1.54) among the analysed variables. CONCLUSIONS: Our results suggest remarkable differences in the mechanisms generating segmental and whole-chromosome mosaicism, indicating that they may deserve different consideration when studying them and when prioritizing them for transfer. Male factor seems to be associated with mosaicism and may be worthy of specific assessment in future studies.

COH outcomes in breast cancer patients for fertility preservation: a comparison with the expected response by age.

PURPOSE: Breast cancer is the most common cancer diagnosed during childbearing age, and fertility preservation is becoming increasingly more essential. However, recent studies indicate a possible poorer response to controlled ovarian hyperstimulation (COH) in cancer patients than in non-cancer controls and a negative impact of BRCA mutations on female fertility. This study aims to evaluate ovarian response and the number of mature oocytes (MII) vitrified in women with breast cancer, with or without BRCA mutation, comparing them to the expected response according to an age-related nomogram. METHODS: This is a retrospective observational study involving sixty-one breast cancer patients who underwent COH for oocyte cryopreservation. The age-specific nomogram was built using 3871 patients who underwent COH due to oocyte donation, fertility preservation for non-medical reasons, or FIVET for male factor exclusively. RESULTS: The mean number of oocytes retrieved was 13.03, whereas the mean number of MII oocytes was 10.00. After the application of the z-score, no statistically significant differences were found compared with the expected response in the general population, neither by dividing patients according to the presence or absence of BRCA mutation nor according to the phase in which they initiated stimulation. CONCLUSION: The results obtained do not support the notion of a negative impact of the BRCA mutation on the ovarian response of women with breast cancer. Women with breast cancer undergoing COH for fertility preservation can expect the ovarian response predicted for their age.

The continuum of ovarian response leading to BIRTH, a real world study of ART in Spain.

BACKGROUND: The first biosimilar of recombinant follicle stimulating hormone (rFSH) launched in Europe was Bemfola® in 2014 following a clinical development programme demonstrating efficacy and safety to the satisfaction of the European Medicines Agency. Since then the increasing use of biosimilar rFSH has provided the opportunity to study both effectiveness across the whole population and the variation of rFSH use during routine clinical care in a real-world setting in Spain. METHODS: This is a real-world study of 1222 women treated in 26 assisted reproduction treatment centres throughout Spain providing experience of the use of a biosimilar recombinant follicle stimulating hormone in four distinct populations. The four populations studied were poor responders, suboptimal responders, normal responders and oocyte donors. The primary endpoint was the total number of oocytes retrieved. Secondary endpoints included number of days of rFSH stimulation, total dose of rFSH administered, number of MII oocytes, number of fertilized oocytes, quality of embryos, number of embryos transferred, implantation rates, clinical pregnancy rates following embryo transfer, number of multiple pregnancies and number of serious adverse reactions, including moderate-to-severe OHSS. RESULTS: Differences were seen across the populations both in the characteristics of the women and ART outcomes suggestive of a continuum of fertility prognosis. In the poor responders, suboptimal responders, normal responders and oocyte donor populations the mean age in years was 39.9 (±SD 3.4), 38.4 (±SD 2.9), 34.4 (±SD 3.3) and 26 (±SD 4.6) respectively and number of oocytes retrieved was 4.1 (±SD 2.7), 8.6 (±SD 6.0), 12.2 (±SD 7.2) and 19.5 (±SD 9.5) respectively. The proportion of embryos graded as best quality was 18.5%, 33.0% and 43.8%, and graded as worst quality was 20.4%, 5.8% and 5.8% for poor responders, suboptimal responders and normal responders respectively. In a similar pattern, for poor responders, suboptimal responders and normal responders the implantation rates were 16.0%, (8/50), 22.4% (49/219), 30.6% (97/317) respectively and clinical pregnancy rates were 23.2% (10/43), 30.4% (59/194) and 37.0% (114/308) respectively. Adverse events were reported in only 7 of 1222 women (0.6%). CONCLUSIONS: Overall the results were consistent with the national ART results reported for Spain, hence this study provides reassurance of the clinical effectiveness of a biosimilar rFSH used in a real world setting. TRIAL REGISTRATION: ClinicalTrials.gov identifier - NCT02941341.

Low progesterone levels on the day before natural cycle frozen embryo transfer are negatively associated with live birth rates.

STUDY QUESTION: Are progesterone (P) levels on the day before natural cycle frozen embryo transfer (NC-FET) associated with live birth rate (LBR)? SUMMARY ANSWER: Regular ovulatory women undergoing NC-FET with serum P levels <10 ng/ml on the day before blastocyst transfer have a significantly lower LBR than those with serum P levels >10 ng/ml. WHAT IS KNOWN ALREADY: The importance of serum P levels around the time of embryo transfer in patients undergoing FET under artificial endometrial preparation has been well established. However, no study has analyzed the importance of serum P levels in patients undergoing FET under a true natural endometrial preparation cycle. STUDY DESIGN, SIZE, DURATION: This was a retrospective cohort study including 294 frozen blastocyst transfers under natural cycle endometrial preparation at a university-affiliated fertility centre between January 2016 and January 2019. PARTICIPANTS/MATERIALS, SETTING, METHODS: All patients had regular menstrual cycles and underwent NC-FET with their own oocytes. Only patients who had undergone serum P measurement between 8 am and 11 am on the day before FET were included. Patients did not receive any external medication for endometrial preparation or luteal phase support. Patients were divided into two groups according to serum P levels below or above 10 ng/ml on the day before FET. Univariate analysis was carried out to describe and compare the cycle characteristics with reproductive outcomes. To evaluate the effect of P, a multivariable logistic model was fitted for each outcome after adjusting for confounding variables. MAIN RESULTS AND THE ROLE OF CHANCE: Mean serum P levels on the day before FET were significantly higher in patients who had a live birth compared to those who did not (14.5 ± 7.0 vs 12.0 ± 6.6 ng/ml, 95% CI [0.83; 4.12]). The overall clinical pregnancy rate (CPR) and LBR were 42.9% and 35.4%, respectively. Patients in the higher P group (>10 ng/ml) had a higher LBR (41.1% vs 25.7%: risk difference (RD) 15.4%, 95% CI [5; 26]) and CPR (48.6% vs 33.0%: RD 15.6%, 95% CI [4; 27]). Patients with higher serum P levels on the day before FET (63% of patients) had an improved LBR (odds ratio: 1.05; 95% CI [1.02; 1.09]). Women with serum P levels <10 ng/ml on the day before FET (37% of patients) had significantly higher weights (62.5 ± 9.9 vs 58.1 ± 7.1 kg, 95% CI [1.92; 6.90]) and BMI (22.9 ± 3.6 vs 21.6 ± 2.7 kg/m2, 95% CI [0.42; 2.25]) compared to patients with P levels >10 ng/ml. LIMITATIONS, REASONS FOR CAUTION: The main limitation of our study is its retrospective design. Other potential limitations are the detection of LH surge through urine testing and the inclusion of patients who did and did not undergo preimplantation genetic testing for aneuploidies. The protocol used in our institution for monitoring NC-FET does not look for the onset of progesterone secretion by the corpus luteum, and a slow luteinisation process or delay of corpus luteum function cannot be ruled out. WIDER IMPLICATIONS OF THE FINDINGS: We provide evidence that a minimum serum P threshold (P >10 ng/ml) might be required for improved reproductive outcomes in NC-FET. This result suggests that there are different mechanisms by which P is produced and/or distributed by each patient. This study also provides an excellent model to evaluate the impact of luteal phase defect through NC-FET. A prospective evaluation to assess whether P supplementation should be individualised according to patient's needs is necessary to support our findings. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used, and there are no competing interests.

Factors associated with serum progesterone concentrations the day before cryopreserved embryo transfer in artificial cycles.

RESEARCH QUESTION: What factors determine serum progesterone concentrations the day before cryopreserved embryo transfer in artificially prepared cycles? DESIGN: Retrospective cohort study at a university-affiliated fertility centre including infertile women under 45 years old using own oocytes who underwent a total of 685 single cryopreserved blastocyst transfers under hormonal therapy. Determinants that affected live birth rate (LBR) were analysed using a multivariate logistic regression. Univariate analysis and multivariate linear regression were used to evaluate independent factors that affect serum progesterone concentrations. RESULTS: Age (odds ratio [OR] 0.93; 95% confidence interval [CI] 0.89-0.96), duration of oestradiol (OR 0.96; 95% CI 0.92-0.99), serum progesterone concentrations (OR 1.04; 95% CI 1.01-1.08) and patients who underwent preimplantation genetic testing for aneuploidies (PGT-A) (OR 2.17; 95% CI 1.55-3.03) were independently associated with LBR. After univariate analysis, determinants of progesterone concentrations were: age, weight, history of a previous cryopreserved embryo transfer with serum progesterone concentrations <10 ng/ml, and time of blood extraction. The multivariate linear regression showed that increasing age presented a positive correlation with progesterone concentrations (ß = 0.11; 95% CI 0.01-0.20). On the contrary, significant negative correlations with progesterone concentrations were shown for a previous history of serum progesterone value <10 ng/ml (ß = -3.13; 95% CI -4.45 to -1.81]), higher weight (ß = -0.05; 95% CI -0.08 to -0.01) and the time of blood sampling during the day (ß = -0.13; 95% CI -0.25 to -0.01). CONCLUSIONS: This study adds more evidence regarding the importance of serum progesterone concentrations before frozen embryo transfer (FET). It also showed that body weight, age, time of blood sampling and a history of low progesterone are determinants associated with progesterone concentrations before blastocyst FET.

Does LH suppression by progesterone-primed ovarian stimulation compared with GnRH antagonist affect live birth rate among oocyte recipients?

RESEARCH QUESTION: Is live birth rate among recipients of donated oocytes different depending on mode of treatment for endogenous LH suppression administered to oocyte donors during ovarian stimulation? DESIGN: A retrospective cohort study of recipients of freshly donated oocytes from oocyte donors who underwent ovarian stimulation with gonadotrophins at a private, university-based infertility clinic between January 2017 and March 2018. For endogenous LH suppression, oocyte donors received daily injections of gonadotrophin releasing hormone antagonist ganirelix (GNR) or daily oral 75 µg desogestrel (DSG) until triggering with 0.2 mg of triptorelin. Three hundred recipient cycles of freshly donated oocytes were included: 154 from oocyte donor DSG cycles and 146 from oocyte donor GNR cycles. RESULTS: Comparison of basal characteristics of oocyte donors showed no differences in mean age, anti-Müllerian hormone levels and body mass index between the oocyte donor DSG p and oocyte donor GNR groups, respectively. Similarly, no differences were observed among mean age of recipients and body mass index. Out of 300 fresh embryo transfers, 190 clinical pregnancies (63.3%) and 150 live births (50%) were achieved. Per embryo transfer clinical pregnancy rate was 66.2% in the DSG recipient group and 60.3% in the GNR recipient group (P = 0.338). Live birth rates were not significantly different between both groups (48.7% among DSG recipient group and 51.4% among GNR recipient group; P = 0.729). CONCLUSIONS: Live birth rate among recipients of donated oocytes does not differ depending on the mode of treatment for endogenous LH suppression administered to the oocyte donors during ovarian stimulation. This information is reassuring and will be of interest to teams using these kinds of protocols, although further research is needed.

Morphokinetics and in vitro developmental potential of monopronucleated ICSI zygotes until the blastocyst stage.

The aim of this study was to provide a more comprehensive understanding of 1PN intracytoplasmic sperm injection (ICSI) zygotes. To achieve this objective, we assessed whether all 1PN-derived embryos showed a similar morphokinetic pattern, and if the morphokinetic behaviour of 1PN-derived embryos was comparable with that of 2PN-derived embryos. In total, 149 1PN ICSI zygotes (study group) and 195 2PN ICSI zygotes (control group) were included in the study. Embryo development potential was evaluated in terms of blastocyst rate. Morphokinetic parameters, including the pronucleus diameter and kinetics of in vitro development, were also analyzed. Embryos derived from 1PN ICSI zygotes showed impaired development compared with 2PN-derived embryos, with blastocyst rates of 28.9% and 67.2%, respectively. The diameter of the pronucleus of 1PN zygotes was larger than that of 2PN zygotes. When compared with 2PN-derived embryos, those derived from 1PN zygotes had a visible pronucleus for a shorter time, in addition to a longer syngamy time and slower kinetic behaviour from two to nine cells. When 1PN-derived blastocysts and 2PN-derived blastocysts were compared, the developmental kinetics were similar in both groups, except for a delayed and longer duration of the compaction phase in 1PN-derived embryos. In conclusion, monopronucleated ICSI zygotes present differences in developmental capacity and morphokinetic behaviour compared with 2PN ICSI zygotes, showing particular morphokinetic parameters related to pronucleus formation. Only the 1PN ICSI-derived embryos that reached the blastocyst stage have similar morphokinetic development to blastocysts from 2PN zygotes.

The effect of type of oral contraceptive pill and duration of use on fresh and cumulative live birth rates in IVF/ICSI cycles.

STUDY QUESTION: Are there any differences in the fresh (LB) and cumulative live birth rates (CLBR) of women undergoing controlled ovarian stimulation (COS) for IVF/ICSI following pretreatment with different types of oral contraceptive pills (OCP) for different durations as compared to no-OCP? SUMMARY ANSWER: OCP administration for an interval of 12- to 30-day treatment period and with a 5-day washout period does not affect clinical pregnancy, LB nor cumulative LB in patients undergoing COS for an IVF cycle. WHAT IS KNOWN ALREADY: The use of OCP is an effective way of treatment planning in IVF/ICSI cycles, but published evidence about its effect on pregnancy and LBR is inconsistent, some studies finding decreased rates but others no difference. STUDY DESIGN, SIZE, DURATION: This is a retrospective analysis carried out in a University-affiliated tertiary centre between January 2009 and December 2017. Overall, 4116 infertile women between 18 and 45 years, who underwent their first ovarian stimulation cycle in our centre, were included. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients were categorised into two groups as receiving OCP (n = 3517) or not (no OCP, n = 599). All patients with OCP pretreatment initiated controlled ovarian stimulation (COS) 5 days post-pill. Overall, two types of OCP were used at the study's centre: ethinylestradiol (EE) 30 µg/desogestrel 150 µg, a third-generation progesterone; or EE 30 µg/drospirenone 3 mg, a fourth-generation progestin with mild antiandrogenic activity. MAIN RESULTS AND THE ROLE OF CHANCE: A total of n = 4116 patients were analysed, (OCP n = 3517 and non-OCP n = 599). The use of OCP was independently associated with a small increase in the number of oocytes retrieved after adjusting for age, BMI, use of OCP, cause of infertility, initial dose (IU), type of gonadotropin, stimulation days, total stimulation units (total IU) (ß 0.22, 95% CI 0.12-0.31). Cumulative LBRs were comparable between groups OCP versus non-OCP (32.4 versus 31.6%, P = 0.712). Following adjustment for age, BMI, infertility diagnosis, starting and total dose, type of gonadotropin, total days of stimulation, type of insemination, number of oocytes retrieved, day of transfer and number of embryos transferred in a multiple logistic analysis, patients using OCPs had a similar probability of achieving a LB as compared with patients not-using OCPs following fresh embryo transfer (ORadj 0.89, 95% CI 0.69-1.15) and a similar probability for CLBR after the use of fresh and frozen embryos (ORadj 0.94, 95% CI 0.73-1.21). No differences were observed in ovarian stimulation and clinical outcomes between drospirenone and desogestrel OCP groups. LIMITATIONS, REASONS FOR CAUTION: Limitations are related to the retrospective nature of the study; despite the sample size, the adjustments and the multivariable regression analysis conducted, we cannot exclude the presence of confounding bias. OCP administration was not randomly assigned, not allowing to exclude the presence of selection bias. Lastly, we only used two types of OCP with durations and washout periods as per institution protocol. Therefore, we cannot exclude that longer duration of administration, a different type of OCP or different pill-free interval might have had an alternative effect on LBR or CLBR; thus, the generalizability of this study's results should be considered with caution. WIDER IMPLICATIONS OF THE FINDINGS: Our study provides reassuring evidence that the use of 12-30 days OCP for cycle programming, prior to IVF, does not decrease the chance of live birth and cumulative live birth rates. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. This research was performed under the auspices of 'Càtedra d'Investigació en Obstetrícia I Ginecologia' of the Department of Obstetrics, Gynaecology and Reproductive Medicine, Hospital Universitario Dexeus, Universitat Autònoma de Barcelona. The authors report no conflict of interest associated with the current study. TRIAL REGISTRATION NUMBER: NA.

Impaired Expression of Ectonucleotidases in Ectopic and Eutopic Endometrial Tissue Is in Favor of ATP Accumulation in the Tissue Microenvironment in Endometriosis.

Endometriosis is a prevalent disease defined by the presence of endometrial tissue outside the uterus. Adenosine triphosphate (ATP), as a proinflammatory molecule, promotes and helps maintain the inflammatory state of endometriosis. Moreover, ATP has a direct influence on the two main symptoms of endometriosis: infertility and pain. Purinergic signaling, the group of biological responses to extracellular nucleotides such as ATP and nucleosides such as adenosine, is involved in the biology of reproduction and is impaired in pathologies with an inflammatory component such as endometriosis. We have previously demonstrated that ectonucleotidases, the enzymes regulating extracellular ATP levels, are active in non-pathological endometria, with hormone-dependent changes in expression throughout the cycle. In the present study we have focused on the expression of ectonucleotidases by means of immunohistochemistry and in situ activity in eutopic and ectopic endometrial tissue of women with endometriosis, and we compared the results with endometria of women without the disease. We have demonstrated that the axis CD39-CD73 is altered in endometriosis, with loss of CD39 and CD73 expression in deep infiltrating endometriosis, the most severe, and most recurring, endometriosis subtype. Our results indicate that this altered expression of ectonucleotidases in endometriosis boosts ATP accumulation in the tissue microenvironment. An important finding is the identification of the nucleotide pyrophophatase/phosphodiesterase 3 (NPP3) as a new histopathological marker of the disease since we have demonstrated its expression in the stroma only in endometriosis, in both eutopic and ectopic tissue. Therefore, targeting the proteins directly involved in ATP breakdown could be an appropriate approach to consider in the treatment of endometriosis.

Effect of embryo transfer difficulty on live birth rates studied in vitrified-warmed euploid blastocyst transfers.

RESEARCH QUESTION: The aim of this study was to investigate the relationship between the different manoeuvres employed or degrees of difficulty during embryo transfer and live birth rate (LBR) in frozen euploid (blastocyst) embryo transfer (FEET). DESIGN: A retrospective, observational study of women undergoing FEET was performed. If the catheter encountered any resistance in its passage through the cervix, a stepwise approach was used. Easy embryo transfer was defined as a direct embryo transfer or use of the outer sheath of the catheter. Difficult embryo transfer was defined as when the process required the use of a Wallace Malleable Stylet (Smiths Medical International Ltd., UK) without or with additional instrumentation such as a tenaculum or uterine sound. RESULTS: The analysis involved 370 FEET. LBR was significantly lower in difficult FEET procedures compared with easy ones (54.5% versus 40.5%, P = 0.026) but significance was lost after adjustment for confounders. Use of the outer sheath use did not affect LBR. Although LBR was significantly lower when the stylet, without or with a tenaculum, was required (odds ratio [OR] 0.56, 95% confidence interval [CI] 0.34-0.93; P < 0.05), no statistically significant reduction was observed after adjustment for confounders (OR 0.81, 95% CI 0.45-1.47). CONCLUSIONS: No significant reduction in LBR was observed after adjustment for confounders between difficult and easy FEET, or when use of stylet without or with a tenaculum was required for embryo transfer. The lack of significance may be due to factors such as the sample size or the use of array comparative genomic hybridization analysis. Further studies are needed to confirm these results.

Deconstructing the myth of poor prognosis for fast-cleaving embryos on day 3. Is it time to change the consensus?

PURPOSE: To determine the developmental competence of fast-cleaving D3 embryos. METHODS: Retrospective study including 4028 embryos from 513 PGT-A cycles performed between July 2014 and June 2017. Embryos were cultured in time-lapse incubators and biopsied at blastocyst stage. Embryos were classified in groups according to the number of cells on D3 (from 2-cell to ≥13 -cell and compacted). A generalized linear mixed model adjusted for confounding factors was performed to assess the chance to give rise to an euploid blastocyst in each group compared with the chance of 8-cell embryos. Implantation and live birth rates were also analyzed. RESULTS: The statistical analysis showed that embryos with 9 to 11 cells had a slightly lower euploid blastocyst rate than 8-cell embryos (OR (95% CI) 0.77 (0.61-0.96)) while embryos with more than 11 cells were found to be just as likely to give rise to an euploid blastocyst as the 8-cell embryos (OR (95% CI) 1.20 (0.92-1.56)). Conversely, slow-cleaving embryos had a significantly lower euploid blastocyst rate than 8-cell embryos (OR (95% CI) 0.31 (0.24-0.39)). Moreover, euploid blastocysts derived from fast-cleaving embryos and from 8-cell embryos exhibit similar live birth rates. No significant differences were found in the chance to give rise a live birth between 8-cell and 9- to 11-cell embryos (OR (95% CI) 1.23 (0.70-2.15)) and > 11-cell embryos (OR (95% CI) 1.09 (0.57-2.09)). CONCLUSIONS: Embryos with more than 11 cells exhibit similar developmental competence to 8-cell embryos. Their poor prognosis should be reconsidered.

What is the clinical impact of the endometrial receptivity array in PGT-A and oocyte donation cycles?

PURPOSE: To evaluate the influence of the endometrial receptivity array (ERA) test on the implantation rate (IR) and pregnancy rate (PR) in patients with previous failed euploid embryo transfers (Euploid-ET) or oocyte donation embryo transfers (Donor-ET). METHODS: Single-center retrospective study of patients with ≥ 1 previous failed Euploi-ET (n = 24) or ≥ 2 failed Donor-ET (n = 32) who underwent an ERA test and a post-ERA Euploid-ET/Donor-ET between 2012 and 2018. Controls were patients with ≥ 1 previously failed Euploid-ET (n = 119) or ≥ 2 failed Donor-ET (n = 158) who underwent Euploid-ET/Donor-ET during the same period without performing an ERA test. Only blastocyst stage embryos were included. IR/PR was compared between the post-ERA ET and the last ET in the control group. RESULTS: There was no statistically significant difference regarding IR [55.6% (34.6-76.5%) vs. 65.0% (56.9-73.1%)] nor PR (58.3% vs.70.6%, p = 0.238) in the Euploid-ET ERA vs. Euploid-ET control groups. In the Donor-ET arm, both IR [26.8% (12.3-41.4%) vs. 57.2% (50.1-64.3%)] and PR (34.4% vs. 65.2%, p = 0.001) were significantly lower in the ERA group. Multivariate analysis confirmed that performing an ERA test did not influence the PR in the Euploid-ET arm and was associated with a diminished PR in the Donor-ET arm. In the ERA group, 41.1% patients were non-receptive (NR). No significant difference was found regarding IR/PR in NR vs. receptive patients in both Euploid-ET/Donor-ET arms. CONCLUSIONS: In our sample, the performance of an ERA test did not improve pregnancy outcomes. Future prospective studies in larger samples are needed to confirm the role of the ERA test in Euploid-ET/Donor-ET.