Top quality blastocyst formation rates in relation to progesterone levels on the day of oocyte maturation in GnRH antagonist IVF/ICSI cycles

Allelic transcriptomic profiling identifies the role of PRD-like homeobox genes in human embryonic-cleavage-stage arrest

Cleavage-stage arrest in human embryos substantially limits the success rate of infertility treatment, with maternal-to-zygotic transition (MZT) abnormalities being a potential contributor. However, the underlying mechanisms and regulators remain unclear. Here, by performing allelic transcriptome analysis on human preimplantation embryos, we accurately quantified MZT progression by allelic ratio and identified a fraction of 8-cell embryos, at the appropriate developmental time point and exhibiting normal morphology, were in transcriptionally arrested status. Furthermore, we identified PAIRED (PRD)-like homeobox transcription factors divergent paired-related homeobox (DPRX) and arginine-fifty homeobox (ARGFX) as factors involved in MZT, whose deficiency severely impairs MZT and lineage specification and leads to aberrant retention of histone acetylation. By reversing the acetylation retention caused by DPRX and ARGFX defects, embryonic arrest can be partially rescued. Our study identifies factors involved in human MZT and elucidates the etiology underlying human cleavage-stage arrest.

Exposure of Porcine Oocytes to Methylparaben During In Vitro Maturation Alters the Expression of Genes Involved in Cumulus Cell Expansion and Steroidogenesis, Decreasing Hyaluronic Acid and Progesterone Synthesis

Parabens are widely used because of their antimicrobial properties in drugs, cosmetics, and food; however, it has been reported that methylparaben may adversely influence female reproduction. Methylparaben decreases oocyte in vitro maturation at a maturation inhibition concentration 50 of 780.31 μM but also decreases oocyte viability at a lethal concentration 50 of 2028.38 μM. Additionally, parabens are endocrine disruptors, affecting steroidogenesis as well as cumulus cell expansion. Therefore, the aim of this study was to elucidate some of the mechanisms by which methylparaben alters cumulus cell expansion and decreases oocyte maturation through the evaluation of gene expression related to cumulus cell expansion, hyaluronic acid, and progesterone synthesis. For this, oocytes were exposed to different methylparaben concentrations of 0 (control), 650, 780, and 1000 μM for 20 and 44 h of in vitro maturation. The cumulus cell expansion rates, maturation rates, gene expression rates, and hyaluronic acid and progesterone concentrations were revaluated after 20 and 44 h of culture. At sublethal concentrations, methylparaben decreased in vitro maturation as well as cumulus cell expansion at 44 h. Additionally, methylparaben decreased the expression of Has2 and Cd44 at 20 and 44 h of maturation. The expression levels of Stard1, Cyp11a1, and Hsd3b1 were also altered by methylparaben exposure at 20 and 44 h of maturation, suggesting its role as an endocrine disruptor. Hyaluronic acid and progesterone concentrations in the culture medium decreased at 20 and 44 h. These findings could partially explain some of the mechanisms by which methylparaben alters female fertility.

The effect of progesterone level on day of trigger on embryo ploidy in egg donor's cycles

PURPOSE

Elevated progesterone (P4) has emerged as a cofounder for embryo quality and recently been investigated in blastocyst aneuploidy rates. In this context, we explored the prevalence of aneuploidy in blastocysts generated from donated eggs according to P4 levels on trigger's day.

METHODS

This retrospective cohort study analyzed data from intracytoplasmic sperm injection (ICSI) cycles using frozen donated oocytes that underwent embryo biopsy (PGT-A) at blastocyst stage. Patients were divided into two groups according to serum P4 on trigger day: < 1.5 ng/mL (group A) and ≥ 1.5 ng/mL (group B). Only euploid embryos were transferred to recipients. Primary outcome was embryo euploidy and aneuploidy rate. Secondary outcomes were number of blastocysts, number of top-quality embryos, number of euploid/aneuploid embryos and clinical pregnancy rate.

RESULTS

259 ICSI PGT-A cycles with frozen donated oocytes were analyzed. Group A included 75 cycles (57 donors; 69 recipients) and group B 184 cycles (115 donors; 163 recipients). The number of blastocysts (3.60 ± 1.52 vs 3.68 ± 1.52, P = 0.667), top-quality embryos (2.27 ± 1.59 vs 2.28 ± 1.43, P = 0.802), euploid embryos (1.92 ± 1.25 vs 1.92 ± 1.13, P = 0.954) and aneuploid embryos (1.23 ± 1.01 vs 1.14 ± 0.94, P = 0.593) were not significantly different between groups A and B, respectively. Euploid embryo rate (A: 0.31 ± 0.20 vs B: 0.30 ± 0.18, P = 0.626), aneuploidy embryo rate (A: 0.21 ± 0.19 vs B: 0.18 ± 0.15, P = 0.436) and clinical pregnancy rate (A: 73% vs B: 82%, P = 0.476) were comparable between the two groups.

CONCLUSIONS

Elevated P4 values on trigger day did not affect embryo ploidy or embryo quality parameters in donated eggs cycles.

Comparison of Cumulative Live Birth Rates Between Progestin and GnRH Analogues in Preimplantation Genetic Testing Cycles

CONTEXT

Progestins have recently been used as an alternative for gonadotropin-releasing hormone (GnRH) analogues to prevent premature luteinizing hormone surge due to the application of vitrification technology. However, the long-term efficacy and safety of a progestin-primed ovarian stimulation (PPOS) regimen, including oocyte competence, cumulative live birth rate (LBR), and offspring outcomes, remain to be investigated.

OBJECTIVE

To compare cumulative LBR of preimplantation genetic testing (PGT) cycles between a PPOS regimen and GnRH analogues.

METHODS

This was a retrospective cohort study at a tertiary academic medical center. A total of 967 patients with good prognosis were categorized into 3 groups: 478 patients received a long GnRH agonist, 248 patients received a GnRH antagonist, and 250 received a PPOS regimen. Medroxyprogesterone 17-acetate was the only progestin used in the PPOS regimen. The primary outcome was cumulative LBR. Secondary outcomes included time to live birth, cumulative rates of biochemical and clinical pregnancy and pregnancy loss, and perinatal outcomes.

RESULTS

The PPOS regimen was negatively associated with cumulative LBR compared with GnRH antagonists and GnRH agonists (28.4% vs 40.7% and 42.7%). The average time to live birth was significantly shorter with GnRH antagonists than with the PPOS regimen. The cumulative biochemical and clinical pregnancy rates were also lower in the PPOS regimen than GnRH analogues, while cumulative pregnancy loss rates were similar across groups. Furthermore, the number and ratio of good-quality blastocysts were significantly reduced in the PPOS regimen compared with GnRH analogues. In addition, perinatal outcomes were comparable across 3 groups.

CONCLUSION

A PPOS regimen may adversely affect cumulative LBR and blastocyst quality in women with good prognosis compared with GnRH analogues in PGT cycles.

Effects of trigger-day progesterone in c-IVF/ICSI cycles on blastocyst culture outcomes

Objective

To assess whether trigger-day progesterone (P) levels in conventional in vitro fertilization (c-IVF)/intracytoplasmic sperm injection (ICSI) cycles are associated with blastocyst culture outcomes.

Methods

In this retrospective analysis, 747 eligible patients (747 cycles) who adopted the gonadotropin-releasing hormone (GnRH) antagonist protocol and underwent c-IVF/ICSI between January 2021 to June 2024 were recruited. The P cutoff values were 1.0 and 1.5 ng/ml when trigger-day serum P was measured, and 4177 day3 (D3) embryos for blastocyst culture were grouped according to trigger-day P levels. Furthermore, the effects of trigger-day P on blastocyst culture outcomes were evaluated.

Results

In total, 747 cycles, 4177 D3 embryos for blastocyst culture were analyzed. After adjustments, multivariate logistic regression analysis revealed that compared with those in the normal level group, available blastocyst rate (adjusted OR, 0.780; 95% CI, 0.645-0.942; P=0.010) and D5 available blastocyst rate (adjusted OR, 0.736; 95% CI, 0.604-0.898; P=0.003) in the high level group were significantly reduced. Subgroup analysis showed that when female age was less than 35 years old, compared with that (36.30%) in the normal level group, the D5 available blastocyst rate (36.92%, adjusted OR, 0.744; 95% CI, 0.602-0.920; P=0.006) in the high level group was significantly reduced. In ICSI cycles, compared with that (28.69%) in the normal level group, the D5 available blastocyst rate (19.13%, adjusted OR, 0.369; 95% CI, 0.194-0.703; P=0.002) in the high level group was significantly decreased.

Conclusions

This study demonstrated that in the c-IVF/ICSI population, the trigger-day slightly elevated P (1.0-1.5ng/ml) was not related to blastocyst culture outcomes, while the trigger-day elevated P (>1.5ng/ml) was an important factor affecting D5 available blastocyst rate, especially when the woman was younger than 35 years old or insemination type was ICSI.

Fewer good-quality cleavage embryos in dydrogesterone-primed ovarian stimulation compared to GnRH antagonist protocol in POSEIDON group 4 patients

OBJECTIVE

To compare the in vitro fertilization (IVF) outcomes of the progestin-primed ovarian stimulation (PPOS) protocol using dydrogesterone and the GnRH antagonist (GnRH-ant) protocol in POSEIDON group 4 patients.

METHODS

This retrospective cohort study analyzed 447 POSEIDON group 4 patients who underwent IVF at a single center. Patients were categorized into GnRH-ant (n = 281) and PPOS (n = 166) groups. Propensity score matching was employed to balance baseline characteristics, yielding 165 patients in each group for comparison. The primary outcomes were the number and quality of cleavage and blastocysts embryos. Secondary outcomes included clinical pregnancy and ongoing pregnancy rates after the first frozen embryo transfer.

RESULTS

Baseline characteristics were balanced between groups after matching. The PPOS group had a significantly lower number of good quality cleavage embryos (adjusted mean ratio 0.80, 95% CI 0.66-0.97) and blastocysts (adjusted mean ratio 0.77, 95% CI 0.62-0.96) compared to the GnRH-ant group. The number of cleavage embryos and good quality blastocysts was comparable between groups. Although not statistically significant, the clinical pregnancy (31.4% vs 36.8%) and ongoing pregnancy rates (20.3% vs 29.9%) after the first embryo transfer tended to be lower in the PPOS group.

CONCLUSIONS

In POSEIDON group 4 patients, the PPOS protocol using dydrogesterone may be associated with lower embryo quality and pregnancy outcomes compared to the GnRH-ant protocol. Further prospective randomized trials are needed to validate these findings.

Investigating dosage effects of ovulation inhibitors on oocyte maturation in assisted reproductive technology: A retrospective study among patients with normal ovarian reserve

The judicious selection of ovulation inhibitors in ovarian stimulation protocols is crucial for the success of assisted reproductive technology (ART). Herein, we investigate the dose-dependent effects of chlormadinone acetate (CMA) and cetrorelix, two distinct ovulation inhibitors, on oocyte maturation in patients with normal ovarian reserve, using univariable and multivariable Poisson regression analyses. Patients undergoing progestin-primed ovarian stimulation (PPOS) with CMA (n = 299) or gonadotropin-releasing hormone antagonist (GnRH-ant) with cetrorelix (n = 605) during their initial in vitro fertilization cycle were enrolled at our center from March 2018 to October 2020 (N = 904). The primary and secondary outcomes were the oocyte maturation and fertilization rates, respectively. After adjusting for several covariates including age, anti-Müllerian hormone levels, total gonadotropin dose, and type of trigger, we calculated the dose-dependent adjusted relative risk (aRR) and 95% confidence interval (CI) for 1 mg of CMA or 0.25 mg of cetrorelix. In the PPOS group, the median age was 34.0 years, and the median total CMA dosage was 22 mg (interquartile range [IQR]: 18.0-32.0). In the GnRH-ant group, the median age was 35.0 years, and the median total cetrorelix dosage was 0.5 mg (IQR 0.5-0.5). The aRR of the maturation rate was 1.003 (95% CI: 0.999-1.007) with PPOS (p = 0.194) and 1.009 (95% CI: 0.962-1.059) with GnRH-ant (p = 0.717). The aRR of the fertilization rate was 1.002 (95% CI: 0.985-1.020) with PPOS (p = 0.783) and 1.022 (95% CI: 0.839-1.246) with GnRH-ant (p = 0.829). Collectively, these findings indicate that within the applied dosages, ovulation inhibitors do not significantly impact oocyte maturation or fertilization rates in patients with normal ovarian reserve. These valuable insights can be applied when designing ART protocols and may guide clinicians in optimizing infertility treatments.

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.

Effect of body mass index on progesterone level on trigger day in gonadotropin-releasing hormone antagonist cycles

OBJECTIVE

To investigate the effect of body mass index (BMI) on progesterone (P) level on trigger day in gonadotropin-releasing hormone antagonist (GnRH-ant) cycles.

METHODS

This study was a retrospective cohort study. From October 2017 to April 2022, 412 in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) patients who were treated with GnRH-ant protocol for controlled ovarian hyperstimulation (COH) in the reproductive center of our hospital were selected as the research objects. Patients were divided into three groups according to BMI level: normal weight group (n = 230):18.5 kg/m2≤BMI < 24 kg/m2; overweight group (n = 122): 24 kg/m2≤BMI < 28 kg/m2; Obesity group (n = 60): BMI ≥ 28 kg/m2. Variables with p < .10 in univariate analysis (BMI, basal FSH, basal P, FSH days, Gn starting dose and E2 level on trigger day) and variables that may affect P level on trigger day (infertility factors, basal LH, total FSH, HMG days and total HMG) were included in the multivariate logistic regression model to analyze the effect of BMI on P level on trigger day of GnRH-ant protocol.

RESULTS

After adjustment for confounding factors, compared with that in normal weight patients, the risk of serum P elevation on trigger day was significantly lower in overweight and obese patients (OR = 0.434 and 0.199, respectively, p < .05).

CONCLUSION

The risk of P elevation on trigger day in GnRH-ant cycles decreased with the increase of BMI, and BMI could be used as one of the predictors of P level on trigger day in GnRH-ant cycles.

Comparison of aneuploidy for patients of different ages treated with progestin-primed ovarian stimulation or GnRH antagonist protocols

RESEARCH QUESTION

Does euploidy status differ among patients of different ages treated with progestin-primed ovarian stimulation (PPOS) or gonadotrophin releasing hormone antagonist (GnRH-a) protocols?

DESIGN

Patients undergoing PGT-A (n = 418; 440 cycles) were enrolled and grouped according to female age (<35 years and ≥35 years). Protocols were as follows: PPOS: <35 years (n = 131; 137 cycles); ≥35 years (n = 72; 80 cycles); GnRH-a: <35 years (n = 149; 152 cycles); ≥35 years (n = 66; 71 cycles).

RESULTS

For cycles treated with PPOS in the older group, rates of euploid blastocyst per metaphase Ⅱ oocyte (15.48% versus 10.47%) and per biopsied blastocyst (54.94% versus 40.88%) were significantly higher than those treated with GnRH-a (P < 0.05). The mosaic rate per biopsied blastocyst was significantly lower for cycles treated with PPOS than cycles treated with GnRH-a (8.64% versus 23.36%) (P < 0.001). In the younger group, no significant difference was found between treatments (P > 0.05). In older and younger groups, the drug to inhibit LH surge was cheaper for cycles treated with PPOS compared with GnRH-a (P < 0.001). Generalized estimation equations based on binomial distribution female age and euploidy rate was significantly negatively correlated for all participants (β -0.109, 95% CI -0.183 to -0.035, P = 0.004), and between GnRH-a protocol (reference: PPOS) and the euploidy rate in the older group (β -0.126, 95% CI -0.248 to -0.004, P = 0.042). Multiple logistic regression indicated that ovarian stimulation protocol was not associated with ongoing pregnancy rate (OR 0.652, 95% CI 0.358 to 1.177; P = 0.14).

CONCLUSIONS

PPOS is suitable for patients undergoing PGT-A, particularly older patients for the higher euploid blastocyst rate attained by PPOS protocol.

Early versus late follicular phase ovarian stimulation: a randomized controlled trial

RESEARCH QUESTION

Is late follicular phase stimulation as efficient as early follicular phase stimulation in a gonadotrophin-releasing hormone (GnRH) antagonist protocol in oocyte donors in terms of the number of oocytes.

DESIGN

In this open label, phase 3, non-inferiority, randomized controlled trial using a two-arm design with a 1:1 allocation ratio, 84 oocyte donors were allocated to the early follicular start group (control group, n = 41) or the late follicular start group (study group, n = 43). In the control group, women followed a fixed GnRH antagonist protocol with recombinant FSH (r-FSH) 225 IU. In the study group, r-FSH 225 IU was initiated in the late follicular phase. The primary outcome was the number of oocytes. The secondary outcomes were the number of mature oocytes, consumption of gonadotrophins and GnRH antagonist, and cost of medication.

RESULTS

The number of oocytes did not differ between the control group and the study group (intent-to-treat analysis 15.5 ± 11.0 versus 14.0 ± 10.7, P = 0.52; per-protocol analysis 18.2 ± 9.7 versus 18.8 ± 7.8, P = 0.62). In addition, the number of mature oocytes did not differ between the groups (14.1 ± 8.1 versus 12.7 ± 8.5, P = 0.48). The duration of stimulation was shorter in the control group (10.0 ± 1.4 versus 10.9 ± 1.5 days, P = 0.01). The total amount of r-FSH used was lower in the control group (2240.7 ± 313.9 IU versus 2453.9 ± 330.1 IU, P = 0.008). A GnRH antagonist was used for approximately 6 days in the control group, while a GnRH antagonist was only prescribed for one woman in the study group (6.0 ± 1.4 days versus 0.13±0.7 days, P < 0.001). There was a significant difference in the cost of medication per cycle between the groups (1147.9 ± 182.8€ in control group versus 979.9 ± 129.0€ in study group, P < 0.001).

CONCLUSIONS

Late follicular phase stimulation is as efficient as early follicular phase stimulation in terms of the number of oocytes.

Progestin-primed ovarian stimulation with letrozole using different doses of medroxyprogesterone acetate per day: a retrospective cohort study

Background

In the progestin-primed ovarian stimulation protocol, the oral administration of medroxyprogesterone acetate has been observed to effectively inhibit the LH surge during ovarian stimulation in patients experiencing infertility. Nevertheless, the use of utilizing medroxyprogesterone acetate during ovarian stimulation can result in more pronounced pituitary suppression, potentially necessitating increased doses of gonadotropins and extended treatment durations. Therefore, it is necessary to determine the optimal dose of medroxyprogesterone acetate, aiming to use relatively lower concentrations of medroxyprogesterone acetate to effectively and safely suppress early LH surges.

Method

This retrospective cohort study included 710 patients who underwent cycles of in vitro fertilization or intracytoplasmic sperm injection and were subjected the progestin-primed ovarian stimulation protocol utilizing letrozole between from 1st January 2021 to 31st December 2021. The study population was divided into low, medium, and high concentration groups based on the daily dosage of medroxyprogesterone acetate.The primary focus of this investigation was on the cumulative live birth rate. Secondary outcomes encompassed the occurrence of a premature surge in luteinizing hormone, the quantity of retrieved oocytes, viable embryos, and high-quality embryos, as well as clinical pregnancy rate, abortion rate, ectopic pregnancy rate, and multiple pregnancy rate.

Results

In this study, significant differences were observed among three groups in various parameters including body mass index, baseline levels of Anti-Müllerian hormone and luteinizing hormone, antral follicle count, total dose of gonadotropin, and duration of gonadotropin administration (p<0.05). The number of oocytes and viable embryos were significantly higher in medium group and higher than those in the low dose group. Following adjustments for confounding factors related to medroxyprogesterone acetate for various outcome measures, we conducted multiple regression analysis to investigate the independent effects of daily medroxyprogesterone acetate dosage within the combined progestin-primed ovarian stimulation and letrozole protocol. Following multivariable regression analysis, no disparities were found in embryo characteristics (number of oocytes retrieved, number of available embryos, number of high-quality embryos) or pregnancy outcomes (clinical pregnancy rate, cumulative live birth rate) among the three groups.

Conclusion

Progestin-primed ovarian stimulation with letrozole using different dose of medroxyprogesterone acetate per day was comparable in terms of the number of oocytes retrieved, the number of high-quality embryos, clinical pregnancy rate and cumulative live birth rate after frozen embryo transfer.

Too many embryos: a critical perspective on a global challenge

Over the past decade, significant endeavors have been directed toward establishing an optimal oocyte number to maximize the chances for successful in vitro fertilization outcomes. The effectiveness of assisted reproductive technologies has greatly improved, and more good-quality embryos are being created in each cycle. However, many of these embryos remain unused. Notably, in Europe, approximately one-third of couples did not use their surplus cryopreserved embryos. Surplus embryos pose a challenge for patients and clinics. Embryo disposal practices are not the same all over the continent, with embryo donation and embryo discharge not allowed in several countries. In this scenario, limiting the number of surplus embryos by reducing the number of inseminated oocytes, according to couple clinical history, could be a strategy.

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.

The late-follicular-phase progesterone to retrieved oocytes ratio in normal ovarian responders treated with an antagonist protocol can be used as an index for selecting an embryo transfer strategy and predicting the success rate: a retrospective large-scale study

Objective

To determine whether the late-follicular-phase progesterone to retrieved oocytes (P/O) ratio during in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) impacts pregnancy outcomes.

Design

12,874 cycles were retrospectively categorized into four groups according to the P/O ratio percentile, with divisions at the 25th, 50th and 75th percentiles.

Results

The clinical pregnancy and live birth rates of fresh cycle embryos in Group D were significantly lower than those in the other three groups (45.1% and 39.0%, 43.2% and 37.2%, 39.6% and 33.5%, 33.4% and 28.2% in Group A, B, C, D, respectively; both P < 0.008). Multivariate logistic regression analysis revealed a significant negative correlation between the P/O ratio and live birth, particularly when the P/O ratio was ≥0.22 (OR = 0.862, 95% CI [0.774-0.959], P = 0.006).

Conclusions

The P/O ratio has certain predictive value for IVF/ICSI pregnancy outcomes and can be used for decision-making decision regarding fresh embryo transfer.

The Effect of Progesterone Elevation on the Day of Trigger Administration: A Review of the Literature

Since the advent of assisted reproductive technology, different variables have been shown to affect pregnancy outcomes. One of the most prevalent studied events is the premature rise in serum progesterone concentrations on the day of trigger administration during cycles of ovarian stimulation. This phenomenon, classically known as premature luteinization, has been observed significantly for decades and has been linked to adverse pregnancy outcomes and lower live birth rates. Ultimately, a quest to find a precise serum progesterone concentration cut-off value that can be effectively used to predict pregnancy outcomes prior to trigger administration is still underway. The purpose of the current research was to study the available literature on the relationship between serum progesterone on the day of trigger administration in controlled ovarian stimulation cycles used for IVF in an attempt to identify a cut-off serum progesterone concentration that can be used to effectively predict future pregnancy outcomes in fresh transfers. This study is a review of the literature and is based on information and data gathered from 36 published articles. The majority of the literature shows that a serum progesterone concentration cut-off of 1.5 ng/ml (4.77 nmol/L) can be used prior to trigger administration to effectively predict pregnancy outcomes. Premature progesterone elevation on the day or prior to the trigger administration is associated with adverse pregnancy outcomes in IVF cycles. Other factors such as follicle number, serum concentration of other hormones, and ovarian response to ovarian stimulation should also be considered to predict the success of IVF protocols.

Proof of concept use of progesterone/estradiol ratio to investigate late follicular progesterone in women with low number of preovulatory follicles

BACKGROUND

The aim of this study was to investigate late follicular progesterone (P) serum levels in women with a low number of preovulatory follicles in the assisted reproductive technologies (ART) setting.

METHODS

Fifty-five consecutive women having four or fewer preovulatory follicles of >14 mm on the day of human chorionic gonadotropin (hCG) administration were prospectively evaluated. Spearman correlation tests were performed between serum estradiol (E2) level, serum P level, P/E2 ratio, number of preovulatory follicles, oocytes and embryos. Women enrolled were further divided into two groups in accordance with the P/E2 ratio on the day of hCG administration and compared.

RESULTS

Serum E2 level correlated positively with P serum level (rs=0.36, P<0.01), number of mature follicles (rs=0.50, P<0.01) and number of oocytes retrieved (rs=0.36, P<0.05), whereas negatively with P/E2 ratio (rs=- 0.68, P<0.01). Likewise, number of preovulatory follicles correlated positively with E2 level (rs=0.50, P<0.01), P level (rs=0.27, P<0.05) and number of oocytes retrieved (rs=0.33, P<0.05), while it correlated negatively with P/E2 ratio (rs=-0.33, P<0.05). Furthermore, women with P/E2 ratio >1 on the day of hCG administration received considerably higher total follicular stimulating hormone (FSH) dosage and achieved significantly lower number of oocytes and embryos as compared to controls.

CONCLUSIONS

The reverse relationship between number of preovulatory follicles and P/E2 ratio implies that P rise is not only the result of increased steroidogenic activity, but other oocyte-follicle disrupted mechanisms seem to be involved. An exaggerated FSH stimulation appears to disrupt further these mechanisms.

Progesterone-primed cycles result in slower embryos without compromising implantation potential and with the advantages of oral administration and potential cost reduction

OBJECTIVE

To study the impact of the use of progesterone on embryo morphokinetics and on the outcomes of intracytoplasmic sperm injection cycles.

DESIGN

Cohort study.

SETTING

Private university-affiliated in vitro fertilization center.

PATIENT(S)

This study included 236 freeze-all intracytoplasmic sperm injection cycles and the resultant 2,768 injected oocytes cultured in a time-lapse imaging incubation system. Patients were matched by age and divided into groups depending on the protocol used to prevent the luteinizing hormone surge: progestin-primed (144 cycles and 1,360 embryos) and gonadotropin hormone-releasing hormone (GnRH) antagonist (144 cycles and 1,408 embryos) groups.

INTERVENTION(S)

The kinetic recorded markers were time to pronuclear appearance and fading, time to 2-8 cells, time to morulation, time to start of blastulation, and time to blastulation. The durations of cell cycles and time to complete synchronous divisions were calculated. The Known Implantation Data Score ranking was recorded. Morphokinetics and clinical outcomes were compared between the groups.

MAIN OUTCOME MEASURE(S)

Embryo morphokinetics and clinical outcomes.

RESULTS

Slower time to pronuclear appearance, time to 2 cells, time to 7 cells, time to start of blastulation, and time to blastulation were observed in embryos derived from progestin-primed cycles than in those from the GnRH antagonist group. No significant differences were noted in any other morphokinetic milestone. Significantly higher cancellation and implantation rates were observed in the progestin-primed group. However, no significant differences were noted in the pregnancy and miscarriage rates. The expenses for treatment using premature GnRH antagonist and progestins were US$318.18 and US$11.05, respectively.

CONCLUSIONS

Exogenous progesterone replaces the GnRH antagonist for the prevention of premature luteinizing hormone surge, in freeze-all cycles, with the advantage of oral administration and potential cost reduction.

Effect of ejaculatory abstinence period on fertilization and clinical outcomes in ICSI cycles: a retrospective analysis

RESEARCH QUESTION

Does ejaculatory abstinence impact fertilization outcomes in intracytoplasmic sperm injection (ICSI) cycles in infertile couples?

DESIGN

This single-centre retrospective observational study included 6919 ICSI cycles from 2013 to 2022. The primary outcome was the assessment of oocyte fertilization, measured in terms of the rate of formation of two-pronuclear (2PN), 3PN and 1PN zygotes. Secondary outcomes were blastulation, cumulative positive β-human chorionic gonadotrophin test and clinical pregnancy rates. Relationships between ejaculatory abstinence and fertilization outcomes, and ejaculatory abstinence and clinical outcomes were evaluated with multivariable analysis, including possible confounders.

RESULTS

A positive association was observed between ejaculatory abstinence and semen sample volume (P < 0.001), sperm concentration (P < 0.001) and total motile sperm count (P < 0.001). No association was found between the 1PN zygote rate and ejaculatory abstinence (P = 0.97). Conversely, for each additional day of ejaculatory abstinence, the likelihood of obtaining 2PN zygotes from all inseminated oocytes decreased by 3% [adjusted odds ratio (aOR) 0.97, 95% CI 0.94-0.99], whilst the likelihood of obtaining 3PN zygotes from all inseminated oocytes increased significantly by 14% (aOR 1.14, 95% CI 1.07-1.22). No significant associations were found between ejaculatory abstinence and blastulation, cumulative pregnancy or miscarriage rates.

CONCLUSIONS

A longer ejaculatory abstinence period significantly decreases the rate of 2PN zygotes, and increases the rate of 3PN zygotes without directly affect blastulation and pregnancy rates.

Comparison of Cumulative Live Birth Rates Between Progestin and GnRH Analogues in Preimplantation Genetic Testing Cycles

CONTEXT

Progestins have recently been used as an alternative for gonadotropin-releasing hormone (GnRH) analogues to prevent premature luteinizing hormone surge due to the application of vitrification technology. However, the long-term efficacy and safety of a progestin-primed ovarian stimulation (PPOS) regimen, including oocyte competence, cumulative live birth rate (LBR), and offspring outcomes, remain to be investigated.

OBJECTIVE

To compare cumulative LBR of preimplantation genetic testing (PGT) cycles between a PPOS regimen and GnRH analogues.

METHODS

This was a retrospective cohort study at a tertiary academic medical center. A total of 967 patients with good prognosis were categorized into 3 groups, of which 478 patients received a long GnRH agonist, 248 patients received a GnRH antagonist, and 250 received a PPOS regimen. Medroxyprogesterone 17-acetate was the only progestin used in the PPOS regimen. The primary outcome was cumulative LBR. Secondary outcomes included time to live birth, cumulative rates of biochemical and clinical pregnancy and pregnancy loss, and perinatal outcomes.

RESULTS

The PPOS regimen was negatively associated with cumulative LBR compared with GnRH antagonists and GnRH agonists (28.4% vs 40.7% and 42.7%). The average time to live birth was significantly shorter with GnRH antagonists than with the PPOS regimen. The cumulative biochemical and clinical pregnancy rates were also lower in the PPOS regimen than GnRH analogues, while cumulative pregnancy loss rates were similar across groups. Furthermore, the number and ratio of good-quality blastocysts were significantly reduced in the PPOS regimen compared with GnRH analogues. In addition, perinatal outcomes were comparable across 3 groups.

CONCLUSION

A PPOS regimen may be adversely affect cumulative LBR and blastocyst quality in women with good prognosis compared with GnRH analogues in PGT cycles.

Effects of different progesterone levels on reproductive outcomes in assisted reproductive technologies: from molecular basis to treatment strategies

PURPOSE

The aim of this narrative review is to offer an overview about the role of progesterone levels on pregnancy outcome in patients undergoing assisted reproductive technologies (ARTs).

METHODS

A detailed computerized search of the literature was performed in the main electronic databases (MEDLINE, EMBASE, Web of Science) to determine the importance of elevated progesterone levels at different stages of the cycle for pregnancy rates in the in vitro fertilization (IVF) cycle. Our review also provides information on the differences between elevated progesterone levels and their interpretation in normal and in poorly responding women.

RESULTS

After careful evaluation, our search strategy yielded a total of 15 included articles, showing the possible factors that may have had an impact on the increased progesterone level before human chorionic gonadotropin (HCG) injection and the different thresholds above which the pregnancy rate was lower. Furthermore, increased progesterone on cycle day 2 or 3 could serve as a marker for increased progesterone in the late follicular phase, which is associated with a lower pregnancy rate.

CONCLUSION

Despite the literature data that support the negative effect of elevated progesterone on fresh cycles, due to lack of randomized controlled trials, the value of measuring progesterone in daily practice is questionable. Available evidence supports the detrimental effect of elevated progesterone in different subgroups of women, although there is still the need for defining different thresholds and durations of high progesterone exposure. The need for various thresholds for different cohorts of women, the inter-assay variability is making this decision harder.

Role and effectiveness of progestins in pituitary suppression during ovarian stimulation for assisted reproductive technology: a systematic review and a meta-analysis

INTRODUCTION

Despite the many unknowns about its exact mechanism, progesterone and progestins are being successfully used to prevent luteinizing hormone (LH) surge during ovarian stimulation for assisted reproductive technology (ART). We will review progestin primed ovarian stimulation (PPOS) protocols in comparison with gonadotropin releasing hormone (GnRH) analogues and each other.

EVIDENCE ACQUISITION

MEDLINE via PubMed; Cochrane Central Register of Controlled Trials (CENTRAL); Scopus; Web of Science were screened with keywords related to assisted reproductive technology, ovarian stimulation progesterone, GnRH analogue and progesterone in several combinations. Search period was from the date of inception of each database until 20 May 2022.

EVIDENCE SYNTHESIS

Live birth or ongoing pregnancy rate per embryo transfer (ET) was similar in PPOS and GnRH antagonist cycles (RR=1.16, 95% CI: 0.93-1.44). Clinical pregnancy rate per ET was likewise similar (RR=1.12, 95% CI: 0.92-1.37). Miscarriage rate per pregnancy was similar with PPOS and GnRH antagonists in autologous cycles (RR=1.01, 95% CI: 0.65-1.55). Pooled analyses showed similar live birth rate between progestins and short GnRH agonist protocols (RR=1.01, 95% CI: 0.49-2.09), however, clinical pregnancy rates per ET were significantly higher with progestins (RR=1.31, 95% CI: 1.06-1.62). Miscarriage rate per pregnancy was similar with progestins (RR=0.82, 95% CI: 0.55-1.21).

CONCLUSIONS

Progestins seem to be an efficient option for pituitary suppression during ovarian suppression, providing similar outcomes for stimulation and pregnancy. They can be especially beneficial for women for whom fresh ET is not considered.

The Ratio of Serum Progesterone (P4) to the Number of Follicles (P4/follicle) is a More Objective Parameter for Euploidy Rate as Compared to Systemic Progesterone Levels

Does the late follicular phase progesterone (P4) and the P4-to-follicle-ratio affect the ploidy state of the biopsied embryos? A retrospective observational study conducted at ART Fertility Clinics Abu Dhabi and Muscat, including all stimulation cycles performed between January 2015 and December 2019. In total, 975 cycles were considered for this study. Inclusion criteria were ovarian stimulation due to primary/secondary infertility, patient's age between 18 and 45 years, ICSI as fertilization method, and patients undergoing preimplantation genetic testing for aneuploidies (PGT-A). Patients with testicular sperm extraction (TESE) and warmed oocytes were excluded. Our results have shown that progesterone had no effect on the euploid rate (p = 0.371). However, when adding the ratio of P4 to the number of follicles that were bigger than 10 mm in the last scan, a negative effect on the euploid rate (p < 0.05) was observed. This study was able to show that the use of only P4 is unable to predict ploidy outcomes. However, by including the number of follicles > 10 mm, a clear association was observed between P4/Foll ratio and euploid rate per cycle. The use of both parameters could aid clinicians in their decision to trigger a patient or continue stimulation. Further prospective studies are warranted to confirm those results.

Progesterone levels during ovarian stimulation in segmented ART cycles inversely correlate with normalized birthweight of neonates conceived through subsequent frozen-thawed embryo transfer

PURPOSE

To evaluate the association between serum progesterone (P) at the day of ovulation trigger and neonatal birthweight in singletons born after frozen-thawed embryo transfer in segmented ART cycles.

METHODS

A retrospective multicenter cohort study involving data from patients who achieved uncomplicated pregnancy and term delivery of ART-conceived singleton babies following a segmented GnRH antagonist cycle. The main outcome was birthweight's z-score of the neonate. Univariate and multivariate linear logistic regression analyses were made to investigate the relation of z-score with variables inherent to the patient and to the ovarian stimulation. The variable P per oocyte was created by dividing the value of progesterone at ovulation trigger by the number of oocytes retrieved at oocyte retrieval.

RESULTS

A total of 368 patients were included in the analysis. At univariate linear regression, the birthweight z-score of the neonate appeared to be inversely related to both P levels at the ovulation trigger (- 0.101, p = 0.015) and P levels per oocyte at trigger (- 1.417, p = 0.001), while it was directly related to the height of the mother (0.026, p = 0.002) and to the number of previous live births (0.291, p = 0.016). In multivariate analysis, both serum P (- 0.1; p = 0.015) and P per oocyte (- 1.347, p = 0.002) maintained the significant inverse association with birthweight z-score after adjusting for height and parity.

CONCLUSIONS

Serum progesterone level on the day of ovulation trigger inversely correlates with normalized birthweight of neonates in segmented GnRH antagonist ART cycles.

Progestin Primed Ovarian Stimulation (PPOS) protocol yields lower euploidy rate in older patients undergoing IVF

BACKGROUND

To explore if exogenous progestin required for progestin primed ovarian stimulation (PPOS) protocol compromises the euploidy rate of patients who underwent preimplantation genetic testing cycles when compared to those who received the conventional gonadotropin-releasing hormone (GnRH) antagonist protocol.

METHODS

This retrospective cohort study analyzed 128 preimplantation genetic testing for aneuploidy (PGT-A) cycles performed from January 2018 to December 2021 in a single university hospital-affiliated fertility center. Infertile women aged 27 to 45 years old requiring PGT-A underwent either PPOS protocol or GnRH-antagonist protocol with in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) for fertilization. Frozen embryo transfers were performed following each PGT-A cycle. Data regarding the two groups were analyzed using the Statistical Package for Social Sciences (SPSS) version 22.0 (SPSS Inc., Chicago, IL).

RESULTS

Patients who underwent PPOS treatment had significantly reduced blastocyst formation rate and euploidy rate compared to those who received the GnRH antagonist protocol. Subgroup-analysis was performed by stratifying patients' age into elder and young subgroups (elder: ≥ 38-year-old, young: < 38-year-old). In the elder sub-population, the blastocyst formation rate of the PPOS group was significantly lower than that of the GnRH-antagonist group (45.8 ± 6.1% vs. 59.9 ± 3.8%, p = 0.036). Moreover, the euploidy rate of the PPOS group was only about 20% of that of  the GnRH-antagonist group (5.4% and 26.7%, p = 0.006). In contrast, no significant differences in blastocyst formation rate (63.5 ± 5.7% vs. 67.1 ± 3.2%, p = 0.45) or euploidy rate (30.1% vs. 38.5%, p = 0.221) were observed in the young sub-population. Secondary outcomes, which included implantation rate, biochemical pregnancy rate, clinical pregnancy rate, live birth rate, and miscarriage rate, were comparable between the two treatment groups, regardless of age.

CONCLUSION

When compared to the conventional GnRH-antagonist approach, PPOS protocol could potentially reduce the euploidy rate in aging IVF patients. However, due to the retrospective nature of this study, the results are to be interpreted with caution. Before the PPOS protocol is widely implemented, further studies exploring its efficacy in larger populations are needed to define the optimal patient selection suitable for this method.

TRIAL REGISTRATION

Human Investigation and Ethical Committee of Chang Gung Medical Foundation (202200194B0).

Serum progesterone on the day of human chorionic gonadotropin (hCG) trigger as a predictor of in-vitro fertilization (IVF) outcome - a retrospective analysis of seven years

OBJECTIVE

To investigate the relationship between progesterone (P4) levels on the day of hCG trigger and IVF outcomes.

METHODS

This is a retrospective analysis of IVF cycles from January-2013 to December-2019 from a single center. Women (21-39 years) submitted to IVF treatment for various infertility factors were included, while donor oocyte cycles and cancelled cycles were excluded from the study. The primary outcome measure was live birth rate.

RESULTS

A total of 2149 cycles were analyzed. Of these, 223 (10.38%) were in the low P4 group (<0.5 ng/ml), 1163 (54.12%) in the normal P4 group (0.5-1.5 ng/ml), and 763 (35.50%) in the high P4 group (>1.5ng/ml). The groups were comparable with respect to age, factor of infertility and baseline AMH. The antagonist protocol was significantly more prescribed to the high P4 group (p<0.001). Live birth rates were 14.4%, 21.6%, and 21% (p<0.001), respectively, in three groups. Univariate analysis found that total cetrotide dose, total number of retrieved and fertilized oocytes, total number of embryos formed, transferred, and vitrified, and P4 on the day of hCG (p<0.001) were statistically significant after adjusting for age and BMI. In multivariate logistic regression after adjusting for age and BMI, only high P4 (aOR:0.60; p<0.001), total cetrotide dose (aOR: 0.82; p<0.001), and total utilizable embryos (aOR:1.11; p=0.029) were statistically significant.

CONCLUSIONS

Having an elevated serum progesterone level on the day of hCG trigger was associated with lower pregnancy rates, but this is still not a robust marker to predict live births. More good quality evidence is needed.

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.

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.

Effects of controlled ovarian stimulation regimens on top-quality blastocyst development and perinatal outcomes with the freeze-all strategy: A retrospective comparative study

OBJECTIVE

This study aimed to determine the effect of ovarian stimulation regimens on the top-quality blastocyst development rate and perinatal outcomes with the freeze-all strategy.

METHODS

A retrospective comparative cohort analysis of 149 in vitro fertilization (IVF) cycles using the freeze-all strategy was conducted. The IVF cycles were stimulated with either a gonadotropin-releasing hormone antagonist or clomiphene citrate along with gonadotropin based on the patient's serum anti-Müllerian hormone level. Oocyte retrieval, fertilization, and embryo culture were performed following standard procedures. All good-quality blastocysts were cryopreserved and used for frozen-thawed embryo transfer (FET) in subsequent cycles. The fertilization, blastulation, and top-quality blastocyst development rates were calculated. The perinatal outcomes of FET cycles, gestational period, and birth weight were assessed.

RESULTS

The main outcome of this study was the top-quality blastocyst development rate, and the secondary outcomes were perinatal parameters (e.g., gestational period and birth weight) between the stimulation regimens. Despite the higher number of usable-quality embryos in the antagonist group, the blastocyst development rate remained comparable (p=0.105). Similarly, perinatal outcomes were comparable in subsequent FET cycles (p=0.538).

CONCLUSION

These findings suggest that the choice between antagonist and clomiphene citrate with gonadotropin as stimulation in controlled ovarian stimulation regimens may not affect the top-quality blastocyst development rate. The IVF outcomes (e.g., clinical pregnancy, miscarriage, and live birth rates) remained unaffected in subsequent FET cycles. Unlike fresh embryo transfer, the birth weight and gestational length were not associated with prior controlled ovarian stimulation regimens when the freeze-all strategy was used.

Effects of trigger-day progesterone in the preimplantation genetic testing cycle on the embryo quality and pregnancy outcomes of the subsequent first frozen-thawed blastocyst transfer

Objective

To assess whether progesterone (P) levels on the trigger day during preimplantation genetic testing (PGT) cycles are associated with embryo quality and pregnancy outcomes in the subsequent first frozen-thawed blastocyst transfer (FET) cycle.

Methods

In this retrospective analysis, 504 eligible patients who underwent ICSI followed by frozen-thawed embryo transfer (FET) with preimplantation genetic test (PGT) between December 2014 and December 2019 were recruited. All patients adopted the same protocol, namely, the midluteal, short-acting, gonadotropin-releasing hormone agonist long protocol. The cutoff P values were 0.5 and 1.5 ng/ml when serum P was measured on the day of human chorionic gonadotropin (HCG) administration, and cycles were grouped according to P level on the day of HCG administration. Furthermore, the effect of trigger-day progesterone on embryo quality and the subsequent clinical outcome of FET in this PGT population was evaluated.

Results

In total, 504 PGT cycles were analyzed. There was no significant difference in the number of euploid blastocysts, top-quality blastocysts, euploidy rate, or miscarriage rate among the three groups (P>0.05). The 2PN fertilization rate (80.32% vs. 80.17% vs. 79.07%) and the top-quality blastocyst rate (8.71% vs. 8.24% vs. 7.94%) showed a downward trend with increasing P, and the between-group comparisons showed no significant differences (P>0.05). The clinical pregnancy rate (41.25% vs. 64.79%; P<0.05) and live birth rate (35.00% vs. 54.93%; P<0.05) in subsequent FET cycles were substantially lower in the high-P group than in the P ≤ 0.5 ng/ml group. After adjustments were made for confounding variables, multivariate logistic regression analysis revealed that the high-P group had a lower clinical pregnancy rate (adjusted OR, 0.317; 95% CI, 0.145-0.692; P=0.004) and live birth rate (adjusted OR, 0.352; 95% CI, 0.160-0.773; P=0.009) than the low-P group in subsequent FET cycles, and the differences were significant.

Conclusions

This study demonstrates that in the PGT population, elevated P on the trigger day may diminish the top-quality blastocyst rate (although there is no difference in the euploidy rate). Trigger-day P is an important factor influencing clinical outcomes in subsequent FET cycles.

Association between the number of oocytes and cumulative live birth rate: A systematic review

The available literature is controversial regarding the association between the number of oocytes retrieved and the cumulative live birth rate (CLBR). Although some authors report a continuous increase in the CLBR with the number of oocytes retrieved, others have found a plateau. A systematic review was conducted, including all eligible studies published until June 2022, to determine the optimal number of oocytes retrieved to maximize the CLBR. We found a positive association between the number of oocytes and the CLBR. However, this association varies according to patients' age. While in patients younger than 35 years, little benefit is derived from increasing the number of oocytes above 25-30, in patients older than 35 years, the number of oocytes seems to improve the CLBR until the extreme of reproductive age is reached. In women aged 44 years or older, the CLBR will be consistently low, independent of the number of oocytes retrieved.

Delayed blastocyst development is influenced by the level of progesterone on the day of trigger

PURPOSE

To evaluate the association between progesterone (P) level on the day of trigger and time to blastulation in IVF cycles.

METHODS

This was a retrospective cohort study with autologous IVF cycles performed at our Institution from January 2019 to December 2021. A total of 1109 IVF cycles were included. The primary outcome was to compare time to blastulation in terms of percentage of expanded (grade 3) blastocysts on day 5 according to progesterone level at trigger.

RESULTS

A total of 3517 blastocysts were analyzed. After dividing progesterone level in quartiles (Q1, P < 0.50 ng/ml; Q2 0.50 ng/ml ≤ P ≤ 0.78 ng/ml; Q3, 0.79 ng/ml ≤ P ≤ 1.15 ng/ml; Q4, P > 1.15 ng/ml), we observed a delay in blastocyst development according to the increasing level of progesterone at trigger (analysis by rank, P-value = 0.01). After adjusting for confounding factors at the multivariate analysis, the percentage of day 5 blastocysts was reduced for Q3 (- 13.8%, 95% CI from - 20.5 to - 7.0%, p < 0.001) and Q4 (- 7.7%, 95% CI from - 15.5 to 0.0%, p = 0.05) compared to Q1 (reference).

CONCLUSIONS

Progesterone levels on day of trigger correlate to the percentage of expanded (grade 3) blastocysts on day 5 and a delayed blastocyst development day 5 is expected for high progesterone levels.

Comparison of cumulative live birth rates between progestin-primed ovarian stimulation protocol and gonadotropin-releasing hormone antagonist protocol in different populations

Objective

To compare cumulative live birth rate (LBR) between progestin-primed ovarian stimulation (PPOS) and GnRH antagonist protocols of preimplantation genetic testing (PGT) cycles in different populations.

Methods

This was a retrospective cohort study. A total of 865 patients were enrolled and separate analyses were performed for three populations: 498 patients with predicted normal ovarian response (NOR), 285 patients with PCOS, and 82 patients with predicted poor ovarian response (POR). The primary outcome was cumulative LBR for one oocyte retrieval cycle. The results of response to ovarian stimulation were also investigated, including numbers of oocytes retrieved, MII oocytes, 2PN, blastocysts, good-quality blastocysts, and usable blastocysts after biopsy, as well as rates of oocyte yield, blastocyst formation, good-quality blastocysts, and moderate or severe OHSS. Univariable and multivariable logistic regression analyses were used to identify potential confounders that may be independently associated with cumulative live birth.

Results

In NOR, the cumulative LBR of PPOS protocol was significantly lower than that of GnRH antagonists (28.4% vs. 40.7%; P=0.004). In multivariable analysis, the PPOS protocol was negatively associated with cumulative LBR (adjusted OR=0.556; 95% CI, 0.377-0.822) compared to GnRH antagonists after adjusting for potential confounders. The number and ratio of good-quality blastocysts were significantly reduced in PPOS protocol compared to GnRH antagonists (2.82 ± 2.83 vs. 3.20 ± 2.79; P=0.032 and 63.9% vs. 68.5%; P=0.021), while numbers of oocytes, MII oocytes and 2PN did not show any significant difference between GnRH antagonist and PPOS protocols. PCOS patients had similar outcomes as NOR. The cumulative LBR of PPOS group appeared to be lower than that of GnRH antagonists (37.4% vs. 46.1%; P=0.151), but not significantly. Meanwhile, the proportion of good-quality blastocysts in PPOS protocol was also lower compared to GnRH antagonists (63.5% vs. 68.9%; P=0.014). In patients with POR, the cumulative LBR of PPOS protocol was comparable to that of GnRH antagonists (19.2% vs. 16.7%; P=0.772). There was no statistical difference in the number and rate of good-quality blastocysts between the two protocols in POR, while the proportion of good-quality blastocysts appeared to be higher in PPOS group compared to GnRH antagonists (66.7% vs. 56.3%; P=0.182). In addition, the number of usable blastocysts after biopsy was comparable between the two protocols in three populations.

Conclusion

The cumulative LBR of PPOS protocol in PGT cycles is lower than that of GnRH antagonists in NOR. In patients with PCOS, the cumulative LBR of PPOS protocol appears to be lower than that of GnRH antagonists, albeit lacking statistical difference, whereas in patients with diminished ovarian reserve, the two protocols were comparable. Our findings suggest the need for caution when choosing PPOS protocol to achieve live births, especially for normal and high ovarian responders.

The Impact of Late Follicular Phase Progesterone Elevation on Cumulative Live Birth Rate and Embryo Quality in 4072 Freeze-All Cycles

Late follicular phase progesterone elevation during in vitro fertilization impedes embryo implantation. It is unclear whether late follicular phase progesterone elevation still has a negative effect on cumulative live births and embryo quality when a freeze-all strategy is adopted. Data from a total of 4072 patients were reviewed. All patients used the freeze-all strategy. Multivariate regression analyses were used to assess the association of progesterone levels with both cumulative live birth and embryo quality. There was no significant difference in the cumulative live birth rate between the groups with progesterone level <1.5 ng/mL and ≥1.5 ng/mL. The progesterone level was not associated with cumulative live birth and embryo quality.

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.

Nomogram models to predict low fertilisation rate and total fertilisation failure in patients undergoing conventional IVF cycles

OBJECTIVES

To establish visualised prediction models of low fertilisation rate (LFR) and total fertilisation failure (TFF) for patients in conventional in vitro fertilisation (IVF) cycles.

DESIGN

A retrospective cohort study.

SETTING

Data from August 2017 to August 2021 were collected from the electronic records of a large obstetrics and gynaecology hospital in Sichuan, China.

PARTICIPANTS

A total of 11 598 eligible patients who underwent the first IVF cycles were included. All patients were randomly divided into the training group (n=8129) and the validation group (n=3469) in a 7:3 ratio.

PRIMARY OUTCOME MEASURE

The incidence of LFR and TFF.

RESULTS

Logistic regressions showed that ovarian stimulation protocol, primary infertility and initial progressive sperm motility were the independent predictors of LFR, while serum luteinising hormone and P levels before human chorionic gonadotropin injection and number of oocytes retrieved were the critical predictors of TFF. And these indicators were incorporated into the nomogram models. According to the area under the curve values, the predictive ability for LFR and TFF were 0.640 and 0.899 in the training set and 0.661 and 0.876 in the validation set, respectively. The calibration curves also showed good concordance between the actual and predicted probabilities both in the training and validation group.

CONCLUSION

The novel nomogram models provided effective methods for clinicians to predict LFR and TFF in traditional IVF cycles.

Comparison of blastocyst euploidy rates following luteal versus follicular phase stimulation in a GnRH antagonist protocol: a prospective study with repeated ovarian stimulation cycles

STUDY QUESTION

Is there any difference in the mean number of euploid embryos following luteal phase start (LS) and follicular phase start (FS) of ovarian stimulation?

SUMMARY ANSWER

The mean number of euploid blastocysts is equivalent independent of whether the inseminated oocytes are derived from FS or LS.

WHAT IS KNOWN ALREADY

Starting ovarian stimulation at any time of the cycle ('random-start') is commonly used for emergency fertility preservation in cancer patients. A few retrospective studies have been published evaluating LS in women undergoing ovarian stimulation in the context of IVF, but there is a lack of robust data on the comparative efficacy of LS versus FS.Although 'random start' is commonly used in cancer survivors, few retrospective and uncontrolled studies have been published evaluating luteal phase stimulation in women undergoing ovarian stimulation in the context of IVF. Owing to this evident lack of robust data on the efficacy of LS, guidelines typically recommend the LS approach only for medical reasons and not in the context of IVF.

STUDY DESIGN, SIZE, DURATION

This is a prospective, equivalence study, with repeated stimulation cycles, conducted between May 2018 and December 2021. Overall, 44 oocyte donors underwent two identical consecutive ovarian stimulation cycles, one initiated in the FS and the other in the LS. The primary outcome of the study was to evaluate whether FS and LS in the same patient would result in equivalent numbers of euploid embryos following fertilization of oocytes with the same sperm sample.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Overall, 44 oocyte donors underwent two consecutive ovarian stimulation protocols with 150 μg corifollitropin alpha followed by 200 IU recombinant FSH (rFSH) in a fixed GnRH antagonist protocol. The only difference between the two cycles was the day of initiation of ovarian stimulation, which was in the early follicular phase (FS) in one cycle, and in the luteal phase (LS) in the other. Forty-four oocyte recipients participated in the study receiving a mean of six metaphase II (MII) oocytes from each stimulation cycle (FS and LS). All MIIs were inseminated with the corresponding recipient's partner sperm (which had been previously frozen) or donor sperm, in order to safeguard the use of the same sample for either the FS or LS. Following fertilization and blastocyst culture, all generated embryos underwent genetic analysis for aneuploidy screening (preimplantation genetic testing for aneuploidy).

MAIN RESULTS AND THE ROLE OF CHANCE

FS resulted in a significantly shorter duration of ovarian stimulation (difference between means (DBM) -1.05 (95% CI -1.89; -0.20)) and a lower total additional dose of daily rFSH was needed (DBM -196.02 (95% CI -319.92; -72.12)) compared with LS. The donors' hormonal profile on the day of trigger was comparable between the two stimulation cycles, as well as the mean number of oocytes (23.70 ± 10.79 versus 23.70 ± 8.81) (DBM 0.00 (95% CI -3.03; 3.03)) and MII oocytes (20.27 ± 9.60 versus 20.73 ± 8.65) (DBM -0.45 (95% CI -2.82; 1.91)) between FS and LS cycles, respectively. Following fertilization, the overall blastocyst formation rate was 60.70% with a euploid rate of 57.1%. Comparisons between the two stimulation cycles did not reveal any significance differences in terms of fertilization rates (71.9% versus 71.4%), blastocyst formation rates (59.4% versus 62%) and embryo euploidy rates (56.9 versus 57.3%) for the comparison of FS versus LS, respectively. The mean number of euploid blastocysts was equivalent between the FS (1.59 ± 1.30) and the LS (1.61 ± 1.17), (DBM -0.02 (90%CI -0.48; 0.44)).

LIMITATIONS, REASONS FOR CAUTION

The study was performed in young, potentially fertile oocyte donors who are patients with high blastocyst euploidy rates. Although results may be extrapolated to young infertile women with good ovarian reserve, caution is needed prior to generalizing the results to infertile women of older age.

WIDER IMPLICATIONS OF THE FINDINGS

The current study provides evidence that initiation of ovarian stimulation in the luteal phase in young potentially fertile women may result in a comparable number of oocytes and comparable blastocyst euploidy rates compared with follicular phase stimulation. This may imply that in case of a freeze-all protocol in young patients with good ovarian reserve, clinicians may safely consider initiation of ovarian stimulation during the luteal phase.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by an unrestricted grant from MSD/Organon. N.P.P. has received Research grants and honoraria for lectures from: Merck Serono, MSD/Organon, Ferring Pharmaceuticals, Besins Intenational, Roche Diagnostics, IBSA, Theramex, Gedeon Richter. F.M., E.C., M.R. and S.G. declared no conflict of interests.

TRIAL REGISTRATION NUMBER

The study was registered at Clinical Trials Gov (NCT03555942).

Comparable Pregnancy Loss and Neonatal Birthweights in Frozen Embryo Transfer Cycles Using Vitrified Embryos from Progestin-Primed Ovarian Stimulation and GnRH Analogue Protocols: A Retrospective Cohort Study

Background: The potential correlation between progestin-primed ovarian stimulation (PPOS) and the risk of compromised embryo competence still lacks sound evidence. Methods: A large retrospective cohort study was used to compare the incidence of pregnancy loss and neonatal birthweights in frozen embryo transfer (FET) cycles using embryos from PPOS and GnRH analogue protocols. Propensity matched scores were used to balance the baseline confounders. Results: A total of 5744 matched cycles with positive hCG test were included to compare the pregnancy outcomes. The incidence of pregnancy loss was similar between PPOS and GnRH analogue groups (19.2% vs. 18.4%, RR 1.02 (0.97, 1.06), p > 0.05). The neonatal birthweights were comparable between two groups, respectively, for singleton births (3337.0 ± 494.4 g vs. 3346.0 ± 515.5 g) and in twin births (2496.8 ± 429.2 g vs. 2533.2 ± 424.2 g) (p > 0.05). Conclusions: The similar incidence of pregnancy loss and neonatal birthweights in FET cycles using embryos from PPOS provided us with a more complete picture about the safety of PPOS.

Premature Progesterone Elevation in in vitro Fertilisation Cycles - Current Perspectives

The impact of premature elevation of progesterone (PPE) on the day of the trigger on pregnancy outcome in in vitro fertilisation (IVF) cycles has been a matter of contention and debate for decades. Research over the last 30 years has indicated that PPE >1.5 ng/ml is associated with declining live birth rates following fresh embryo transfer. Freeze-only approach has become a universal solution to overcome the issue of PPE. However, the topic is still mired with controversy. Few studies have not shown a negative impact on pregnancy rates. The impact of PPE on embryological parameters such as oocyte and embryo quality and ploidy is still very controversial. An important contentious issue is the choice of the threshold P value above which it is considered abnormal and a freeze-all strategy would be cost-effective. Currently, though a cutoff of >1.5 ng/ml is widely used, practices are not uniform and varying thresholds from 0.4 to 3 ng/ml are utilised. This review addresses the current understanding of PPE in IVF and the above controversies. The incidence, aetiology and source of progesterone rise, impact on endometrial receptivity, oocyte and embryo quality, impact on live birth and cumulative live birth and impact on frozen embryo transfer and donor oocyte cycles are discussed. Current controversies regarding the optimal threshold, assay performance and future directions are addressed.

Effects of Elevated Progesterone Levels on the Day of hCG on the Quality of Oocyte and Embryo

This study is designed to investigate the effects of increased progesterone (P4) levels on the quality of retrieved oocytes and embryos during IVF. This retrospective analysis included 982 all-freezing in vitro fertilization (IVF) cycles (conducted between November 2019 and June 2020 at CHA Fertility Center Bundang, South Korea) in which serum P4 levels were measured on the day of human chorionic gonadotropin (hCG) administration. Our study revealed that the serum P4 levels on the day of hCG administration are strongly associated with the rates of oocyte maturation, displaying a positive correlation in patients with serum P4 < 2.25 ng/mL (p = 0.025). Moreover, patients with serum P4 < 1.25 ng/mL showed relatively low fertilization rates (p = 0.037), and the rates of good embryo retrieval were significantly increased with the serum P4 level < 1.5 ng/mL (p = 0.001). Interestingly, serum P4 level on the day of hCG administration affects the rate of good-quality embryo development, especially at the cleavage stage, and is associated with the status of ovarian responses. Our current study suggests that serum P4 level on the day of hCG administration negatively affects the rates of oocyte maturation, fertilization, and the development of good embryos.

Estradiol to progesterone ratio is not a predictor of oocyte maturity at time of ovulation trigger

Purpose

To evaluate the relationship between progesterone and oocyte maturity rate via estradiol to progesterone ratio (E/P) at the time of ovulatory trigger.

Methods

This is a retrospective cohort study of first autologous IVF cycles from January to December 2018 from a private practice fertility center. Serum estradiol and progesterone levels were measured on the day of ovulatory trigger. E/P was calculated to control for degree of response. Embryos were cultured to the blastocyst stage for trophectoderm biopsy. Preimplantation genetic testing for aneuploidy (PGT-A) was performed using next-generation sequencing (NGS). Oocyte retrieval rate (oocytes retrieved/follicles ≥ 13 mm), maturity rate (MII/oocytes retrieved), and euploid rate (euploid/total biopsied embryos) were calculated. Clinical pregnancy, ongoing pregnancy (> 10 weeks), and live births following frozen embryo transfer (FET) were examined in relation to E/P. Regression analyses were performed to analyze E/P as a categorical value (defined by quartile) on oocyte maturity.

Results

Two hundred eleven women underwent controlled ovarian hyperstimulation and had steroid levels at trigger available. Mean E at trigger was 3449 ± 2040 pg/mL while mean P was 1.13 ± 0.58 ng/mL, with mean E/P of 3.36 + 2.04. There were no differences between quartiles of E/P with respect to retrieval, maturity rate, or euploid rate. Two hundred eleven IVF cycles resulted in 138 euploid frozen embryo transfers. There were no differences between quartiles of E/P with respect to clinical pregnancy, ongoing pregnancy, or live birth rate.

Conclusion

E/P ratio at the time of trigger does not impact oocyte retrieval rate, maturity rate, or euploid rate. Pregnancy and live birth outcomes were also not impacted.

Towards an Improved Understanding of the Effects of Elevated Progesterone Levels on Human Endometrial Receptivity and Oocyte/Embryo Quality during Assisted Reproductive Technologies

Ovarian stimulation is an indispensable part of IVF and is employed to produce multiple ovarian follicles. In women who undergo ovarian stimulation with gonadotropins, supraphysiological levels of estradiol, as well as a premature rise in progesterone levels, can be seen on the day of hCG administration. These alterations in hormone levels are associated with reduced embryo implantation and pregnancy rates in IVF cycles with a fresh embryo transfer. This article aims to improve the reader’s understanding of the effects of elevated progesterone levels on human endometrial receptivity and oocyte/embryo quality. Based on current clinical data, it appears that the premature rise in progesterone levels exerts minimal or no effects on oocyte/embryo quality, while advancing the histological development of the secretory endometrium and displacing the window of implantation. These clinical findings strongly suggest that reduced implantation and pregnancy rates are the result of a negatively affected endometrium rather than poor oocyte/embryo quality. Understanding the potential negative impact of elevated progesterone levels on the endometrium is crucial to improving implantation rates following a fresh embryo transfer. Clinical studies conducted over the past three decades, many of which have been reviewed here, have greatly advanced our knowledge in this important area.

Impact of Elevated Progesterone in Late Follicular Phase on Early Pregnancy Outcomes and Live Birth Rate After Fresh Embryo Transfers

Objective: To investigate the effect of progesterone elevation during late follicular phase on early pregnancy outcomes and live births after fresh embryo transfers.

Methods: Patients who underwent IVF/ICSI treatment cycles were retrospectively enrolled. The effect of progesterone elevation was analyzed on early pregnancy outcome and live births after fresh embryo transfers.

Results: A total of 2,404 patients were enrolled on the day of HCG triggering (HCG0), 1,584 patients on the day before HCG triggering (HCG-1), and 800 patients 2 days before HCG triggering (HCG-2). With a 1 ng/ml increase in the progesterone level on HCG0 day when the progesterone level was ≥1.5 ng/ml, the clinical pregnancy rate decreased by 60% (95% CI: 0.2–0.7, p = 0.004), the intrauterine pregnancy rate decreased by 70% (95% CI: 0.2–0.7, p = 0.003), and the live birth rate decreased by 70% (95% CI: 0.1–0.7, p = 0.004). With a 1 ng/ml increase in the progesterone level on HCG-1 day, the clinical pregnancy rate decreased by 90% (95% CI: 0.0–0.5, p = 0.003) when the progesterone level was ≥1.6 ng/ml, the intrauterine pregnancy rate decreased by 90% (95% CI: 0.0–0.5, p = 0.001) when the progesterone was ≥1.5 ng/ml, and the live birth rate decreased by 90% (95% CI: 0.0–0.6, p = 0.015) when the progesterone was ≥1.7 ng/ml. On HCG-2 day when the progesterone was ≥1.2 ng/ml, the clinical pregnancy rate decreased by 80% (95% CI: 0.1–0.6, p = 0.003), and the intrauterine pregnancy rate decreased by 70% (95% CI: 0.1–0.7, p = 0.007) with a 1 ng/ml increase in the progesterone level.

Conclusion: Elevated progesterone level during the late follicular phase is an independent risk factor affecting the clinical pregnancy rate, intrauterine pregnancy rate, and live birth rate among infertile patients undergoing IVF/ICSI after fresh embryo transfers. When the progesterone level exceeds a certain level, the early pregnancy and live birth rates after fresh embryo transfers show a rapid downward trend.

COVID-19 Vaccination Does Not Affect Reproductive Health Parameters in Men

With the implementation of COVID-19 vaccine up-take, doubts regarding the impact of immunization on future fertility have begun to emerge. We have examined vaccine safety on male reproductive health. We set up a multicentre (three infertility centers), retrospective study in order to assess semen parameters and fertilization rate of one hundred-six men in a pairwise comparison between the first and second assisted reproduction technology (ART) attempt, performed respectively before and after COVID-19 vaccination. Median time (range) between the first vaccine dose and the second ART cycle was 75 days (39-112). Semen parameters did not change before and after the exposure. Fertilization rate was also similar before and after vaccination. Twenty-five patients (24%) were oligozoospermic before the vaccination while 26 (25%) after the exposure (P = 0.87). Severe asthenozoospermia were present in 11 patients before as well as after the exposure. No difference was observed even after considering different types of vaccines (mRNA or viral vector). COVID-19 vaccination did not affect sperm quality and fertilization capacity of men undergoing ART treatments and should be considered safe for men's reproductive health.

Analysis of maturation dynamics and developmental competence of in vitro matured oocytes under time-lapse monitoring

BACKGROUND

To improve the developmental competence of in vitro cultured oocytes, extensive literature focused on maturation rate improvement with different additives in culture medium, while studies investigating the maturation dynamics of oocytes during in vitro maturation (IVM) and the influencing factors on oocyte viability are scarce.

METHODS

The study involved a retrospective observation by time-lapse monitoring of the IVM process of 157 donated GV oocytes from 59 infertile couples receiving ICSI in 2019, in Tongji Hospital, Wuhan, China. The GV oocytes derived from controlled ovarian hyperstimulation (COH) cycles underwent rescue IVM (R-IVM), and the maturation dynamics, including GVBD time (GV-MI), time from GVBD to maturation (MI-MII), maturation time (GV-MII), and MII arrest duration (MII-ICSI), were recorded by time-lapse monitoring. The matured oocytes were inseminated at different MII arrest points and subsequent embryo developments were assessed. The effects of baseline clinical characteristics, oocyte diameters, and maturation dynamics on the developmental competence of the oocytes were also analyzed.

RESULTS

Totally, 157 GV oocytes were collected. GVBD happened in 111 oocytes, with a median GV-MI duration of 3.7 h. The median MI-MII duration was 15.6 h and the median GV-MII duration was 19.5 h. The maturation rate reached 56.7% at 24 h and 66.9% at 48 h, and the clinical factors, including patient age, FSH level, AMH level, ovarian stimulation protocol, and serum estradiol and progesterone levels on hCG trigger day, showed no effects on the 24-h maturation rate. The normal fertilization rate of oocytes resuming meiosis within 8 h and matured within 24 h was significantly higher than that of oocytes resuming meiosis after 8 h and matured after 24 h. Furthermore, among those oocytes matured within 24 h, the high-quality embryo formation rate of oocytes resuming meiosis within 4.5 h and matured within 19 h was significantly higher. All stated time was measured from the start point of IVM. Additionally, for oocytes from patients with serum progesterone levels less than 1 ng/ml on hCG trigger day, the high-quality embryo formation rate was significantly increased.

CONCLUSION

R-IVM technology could increase the available embryos for patients in routine COH cycles, but excessive culture beyond 24 h is not recommended. GV-MI duration of the oocyte, recorded by time-lapse system, and serum progesterone levels of patients on hCG trigger day can significantly affect the developmental potential of the IVM oocytes.

Single oral dose of vitamin D3 supplementation prior to in vitro fertilization and embryo transfer in normal weight women: the SUNDRO randomized controlled trial

BACKGROUND

Improving in vitro fertilization success is an unmet need. Observational studies have suggested that women with deficient or insufficient vitamin D have lower chances of in vitro fertilization success, but whether supplementation improves clinical pregnancy rate remains unclear.

OBJECTIVE

This study aimed to determine whether oral vitamin D₃ supplementation improves clinical pregnancy in women undergoing an in vitro fertilization cycle.

STUDY DESIGN

The "supplementation of vitamin D and reproductive outcome" trial is a 2-center randomized superiority double-blind placebo-controlled trial. Subjects were recruited between October 2016 and January 2019. Participants were women aged 18 to 39 years with low vitamin D (peripheral 25-hydroxyvitamin D of <30 ng/mL), serum calcium of ≥10.6 mg/dL, body mass index of 18 to 25 kg/m², and antimüllerian hormone levels of >0.5 ng/mL and starting their first, second, or third treatment cycle of conventional in vitro fertilization or intracytoplasmic sperm injection. The primary outcome was the cumulative clinical pregnancy rate per cycle. Pregnancies obtained with both fresh or frozen embryo transfers were included. Clinical pregnancy was defined as an intrauterine gestational sac with a viable fetus. The primary analysis was performed according to the intention-to-treat principle and could also include natural conceptions. Secondary outcomes included total dose of gonadotropins used, embryologic variables (number of oocytes retrieved, number of suitable oocytes retrieved, fertilization rate, and rate of top-quality embryos), and clinical outcomes (miscarriage rate and live birth rate).

RESULTS

Overall, 630 women were randomized 2 to 12 weeks before the initiation of the in vitro fertilization cycle to receive either a single dose of 600,000 IU of vitamin D₃ (n=308) or placebo (n=322). Interestingly, 113 (37%) and 130 (40%) women achieved a clinical pregnancy in the treatment and placebo groups, respectively (P=.37). The risk ratio of clinical pregnancy in women receiving vitamin D₃ was 0.91 (95% confidence interval, 0.75-1.11). Compared with the placebo, vitamin D₃ supplementation did not improve the rate of clinical pregnancy. Exploratory subgroup analyses for body mass index, age, indication to in vitro fertilization, ovarian reserve, interval between drug administration and initiation of the cycle, and basal levels of 25-hydroxyvitamin D failed to highlight any clinical situation that could benefit from the supplementation.

CONCLUSION

In women with normal weight with preserved ovarian reserve and low vitamin D levels undergoing in vitro fertilization cycles, a single oral dose of 600,000 IU of vitamin D₃ did not improve the rate of clinical pregnancy. Although the findings do not support the use of vitamin D₃ supplementation to improve in vitro fertilization success rates, further studies are required to rule out milder but potentially interesting benefits and explore the effectiveness of alternative modalities of supplementation.

The effect of late-follicular phase progesterone elevation on embryo ploidy and cumulative live birth rates

RESEARCH QUESTION

Does late-follicular phase progesterone elevation have a deleterious effect on embryo euploidy, blastocyst formation rate and cumulative live birth rates (CLBR)?

DESIGN

A multicentre retrospective cross-sectional study including infertile patients aged 18-40 years who underwent ovarian stimulation in a gonadotrophin-releasing hormone antagonist protocol and preimplantation genetic testing for aneuploidies (PGT-A) followed by a freeze-all strategy and euploid embryo transfer between August 2017 and December 2019. The sample was stratified according to the progesterone concentrations on the day of trigger: normal (≤1.50 ng/ml) and high (>1.50 ng/ml). Moreover, sensitivity analyses were performed to determine whether different conclusions would have been drawn if different cut-offs had been adopted. The primary outcome was the embryo euploidy rate. Secondary outcomes were the blastocyst formation rate, the number of euploid blastocysts and CLBR.

RESULTS

Overall 1495 intracytoplasmic sperm injection PGT-A cycles were analysed. Late-follicular phase progesterone elevation was associated with significantly higher late-follicular oestradiol concentrations (2847.56 ± 1091.10 versus 2240.94 ± 996.37 pg/ml, P < 0.001) and significantly more oocytes retrieved (17.67 ± 8.86 versus 12.70 ± 7.00, P < 0.001). The number of euploid embryos was significantly higher in the progesterone elevation group (2.32 ± 1.74 versus 1.86 ± 1.42, P = 0.001), whereas the blastocyst formation rate (47.1% [43.7-50.5%] versus 51.0% [49.7-52.4%]), the embryo euploidy rate (48.3% [44.9-51.7%] versus 49.1% [47.7-50.6%], the live birth rate in the first frozen embryo transfer (34.1% versus 31.1%, P = 0.427) and CLBR (38.9% versus 37.0%, P = 0.637) were not significantly different between the two groups.

CONCLUSIONS

Euploidy rate and CLBR do not significantly differ among PGT-A cycles with and without late-follicular progesterone elevation in a freeze-all approach.

Global transcriptomic changes occur in uterine fluid-derived extracellular vesicles during the endometrial window for embryo implantation

STUDY QUESTION

Are uterine fluid-derived extracellular vesicles (UF-EVs) a 'liquid biopsy' reservoir of biomarkers for real-time monitoring of endometrial status?

SUMMARY ANSWER

The transcriptomic cargo of UF-EVs reflects the RNA profile of the endometrial tissue as well as changes between the non-receptive and the receptive phase, possibly supporting its use for a novel endometrial receptivity test.

WHAT IS KNOWN ALREADY

EVs have been previously isolated from uterine fluid, where they likely contribute to the embryo-endometrium crosstalk during implantation. Based on a meta-analysis of studies on endometrial tissue implantation-associated genes and the human exosomes database, 28 of the 57 transcripts considered as receptivity markers refer to proteins present in human exosomes. However, the specific transcriptomic content of receptive phase UF-EVs has yet to be defined.

STUDY DESIGN, SIZE, DURATION

Two experimental series were set up. First, we simultaneously sequenced RNA species derived from paired UF-EVs and endometrial tissue samples collected from physiologically cycling women. Second, we analyzed RNA species of UF-EVs collected during the non-receptive (LH + 2) and receptive (LH + 7) phase of proven fertile women and from the receptive (LH + 7) phase of a population of women undergoing ART and transfer of euploid blastocysts.

PARTICIPANTS/MATERIALS, SETTING, METHODS

For paired UF-endometrial tissue sampling, endometrial tissue biopsies were obtained with the use of a Pipelle immediately after UF collection performed by lavage of the endometrial cavity. Overall, n = 87 UF samples were collected and fresh-processed for EV isolation and total RNA extraction, while western blotting was used to confirm the expression of EV protein markers of the isolated vesicles. Physical characterization of UF-EVs was performed by Nanoparticle Tracking Analysis. To define the transcriptomic cargo of UF-EV samples, RNA-seq libraries were successfully prepared from n = 83 UF-EVs samples and analyzed by RNA-seq analysis. Differential gene expression (DGE) analysis was used to compare RNA-seq results between different groups of samples. Functional enrichment analysis was performed by gene set enrichment analysis with g:Profiler. Pre-ranked gene set enrichment analysis (GSEA) with WebGestalt was used to compare RNA-seq results with the gene-set evaluated in a commercially available endometrial receptivity array.

MAIN RESULTS AND THE ROLE OF CHANCE

A highly significant correlation was found between transcriptional profiles of endometrial biopsies and pairwise UF-EV samples (Pearson's r = 0.70 P < 0.0001; Spearman's ρ = 0.65 P < 0.0001). In UF-EVs from fertile controls, 942 gene transcripts were more abundant and 1305 transcripts less abundant in the LH + 7 receptive versus the LH + 2 non-receptive phase. GSEA performed to evaluate concordance in transcriptional profile between the n = 238 genes included in the commercially available endometrial receptivity array and the LH + 7 versus LH + 2 UF-EV comparison demonstrated an extremely significant and consistent enrichment, with a normalized enrichment score (NES)=9.38 (P < 0.001) for transcripts up-regulated in LH + 7 in the commercial array and enriched in LH + 7 UF-EVs, and a NES = -5.40 (P < 0.001) for transcripts down-regulated in LH + 7 in the commercial array and depleted in LH + 7 UF-EVs. When analyzing LH + 7 UF-EVs of patients with successful versus failed implantation after transfer of one euploid blastocyst in the following cycle, we found 97 genes whose transcript levels were increased and 64 genes whose transcript levels were decreased in the group of women who achieved a pregnancy. GSEA performed to evaluate concordance in transcriptional profile between the commercially available endometrial receptivity array genes and the comparison of LH + 7 UF-EVs of women with successful versus failed implantation, demonstrated a significant enrichment with a NES = 2.14 (P = 0.001) for transcripts up-regulated in the commercial array in the receptive phase and enriched in UF-EVs of women who conceived, and a not significant NES = -1.18 (P = 0.3) for transcripts down-regulated in the commercial array and depleted in UF-EVs. In terms of physical features, UF-EVs showed a homogeneity among the different groups analyzed except for a slight but significant difference in EV size, being smaller in women with a successful implantation compared to patients who failed to conceive after euploid blastocyst transfer (mean diameter ± SD 205.5± 22.97 nm vs 221.5 ± 20.57 nm, respectively, P = 0.014).

LARGE SCALE DATA

Transcriptomic data were deposited in NCBI Gene Expression Omnibus (GEO) and can be retrieved using GEO series accession number: GSE158958.

LIMITATIONS, REASONS FOR CAUTION

Separation of RNA species associated with EV membranes might have been incomplete, and membrane-bound RNA species-rather than the internal RNA content of EVs-might have contributed to our RNA-seq results. Also, we cannot definitely distinguish the relative contribution of exosomes, microvesicles and apoptotic bodies to our findings. When considering patients undergoing ART, we did not collect UFs in the same cycle of the euploid embryo transfer but in the one immediately preceding. We considered this approach as the most appropriate in relation to the novel, explorative nature of our study. Based on our results, a validation of UF-EV RNA-seq analyses in the same cycle in which embryo transfer is performed could be hypothesized.

WIDER IMPLICATIONS OF THE FINDINGS

On the largest sample size of human EVs ever analyzed with RNA-seq, this study establishes a gene signature to use for less-invasive endometrial receptivity tests. This report is indeed the first to show that the transcriptome of UF-EVs correlates with the endometrial tissue transcriptome, that RNA signatures in UF-EVs change with endometrial status, and that UF-EVs could serve as a reservoir for potential less-invasive collection of receptivity markers. This article thus represents a step forward in the design of less-invasive approaches for real-time monitoring of endometrial status, necessary for advancing the field of reproductive medicine.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by a competitive grant from European Society of Human Reproduction and Embryology (ESHRE Research Grant 2016-1). The authors have no financial or non-financial competing interests to disclose.

TRIAL REGISTRATION NUMBER

NA.

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.