Day Of Frozen-thawed Embryo Transfer Research Articles

P-414 Evaluation of small non-coding RNAs in uterine fluid in the diagnosis of endometrial receptivity in assisted reproductive technology programs

Abstract Study question To analyze endometrial receptivity in patients undergoing frozen-thawed embryo transfer (FET) based on the expression of small non-coding RNAs (sncRNAs): microRNAs and piwiRNAs. Summary answer According to our studies, the expression of sncRNAs in uterine aspirate may become an additional non-invasive and effective way to determine endometrial receptivity. What is known already Today, infertility remains an important medical and social problem. According to statistics, the effectiveness of ART programs remains at the level of 30-40%. Violation of the implantation mechanism is associated with a shift in the “implantation window” period and endometrial receptivity. Therefore, the search for an ideal marker of endometrial receptivity is a priority. Studying the expression of sncRNAs in endometrial secretions or uterine aspirate may become a potential marker of endometrial receptivity. Study design, size, duration The study included 102 infertile couples with women aged from 23 to 40 years. The patients were divided into two groups depending on the preparation of the endometrium for the FET: group 1 - 42 patients with natural cycle (NC); group 2 - 60 patients with hormone replacement therapy (HRT). SncRNAs were assessed in uterine aspiration on the day of FET. Participants/materials, setting, methods Uterine fluid was carried out in a volume of 5 to 50 μl with noninvasive technique. Next, the material was sent to the laboratory of applied transcriptomics for identification of sncRNAs. Quantitative assessment of sncRNAs in the endometrial secretion on the day of FET was carried out by deep sequencing on the NextSeq 500/550 platform (Illumina). Main results and the role of chance Logistic regression models were constructed for predicting pregnancy and endometrial receptivity based on the expression profiles of microRNAs and piwiRNAs in uterine aspirate, which are with 95% sensitivity and 74% specificity in the case of a combination of miR-34c-5p, miR-363–3p, miR-1180–3p, miR-361–3p, miR-183–5p (AUC = 0.91, p < 0.001) or with 74% sensitivity and 87% specificity in the case of a combination of molecules piR_004152, piR_020541, piR_001318, piR_014923, piR_017716 (AUC = 0.81, p < 0.001) determine the readiness of the endometrium for embryo implantation in the FET. In the NC and HRT groups, statistically significant differences were established between patients who became pregnant and patients with a negative result of the ART program in terms of baseline progesterone levels (p < 0.001). In the HRT group, positive correlations were revealed between endometrial thickness on the day of embryo transfer and the baseline level of progesterone (p = 0.04, r = 0.28). Limitations, reasons for caution The study was limited in sample size of patients and requires further randomized studies. Wider implications of the findings For the first time, a test system has been developed for assessing endometrial receptivity based on the expression of sncRNAs in patients both in the NC and in the HRT during the FET. It was found that increased initial progesterone levels correlate with positive outcomes of ART programs. Trial registration number not applicable

P-651 Neither high nor low serum progesterone levels affect clinical outcomes in Artificially prepared-frozen embryo transfer cycles using intramuscular progesterone

Abstract Study question Does serum progesterone level on the day of frozen-thawed embryo-transfer (FET) correlate with the likelihood of achieving pregnancy in artificial FET cycles utilizing intramuscular progesterone? Summary answer Serum progesterone levels on the day of FET do not correlate with the likelihood of achieving a pregnancy in artificial FET cycles employing intramuscular progesterone. What is known already There is scientific evidence suggesting that serum progesterone levels under a specific cutoff level on the day of FET significantly decrease the clinical outcomes in patients under artificial endometrial preparation using micronized vaginal progesterone. However, no substantial evidence exists in patients under artificial endometrial preparation using intramuscular progesterone. Study design, size, duration This prospective cohort study was conducted from February to December 2022 and enrolled 353 patients undergoing FET in hormone replacement therapy (HRT) cycles using intramuscular progesterone until the day of embryo transfer. Participants/materials, setting, methods The study included women aged 21-40 years old undergoing FET, triple layer endometrium >7mm, and ≥2 high-quality embryos (Gardner’s grade 3/4/5/AA/AB/BA/BB) available. Exclusion criteria included patients with uncontrolled diabetes, hypertension, heart disease, known autoimmune diseases, uterine infertility factor, severe male factor infertility (total sperm count < 5 million/ml), and cases requiring surgically retrieved sperm for ICSI. Main results and the role of chance The cohort had an average age of 32.09 ± 4.19 years, BMI of 24.70 ± 3.07 kg/m², and endometrial thickness of 8.87 ± 1.06 mm on the day of embryo transfer. The mean serum progesterone level was 31.36 ± 13.78 ng/ml. Participants were categorized into quartiles based on serum progesterone levels. :Q1 (<21.7 ng/ml), Q2 (21.7-28.1 ng/ml), Q3 (28.2-40.0 ng/ml), and Q4 (≥40.0 ng/ml). No significant difference in Clinical Pregnancy Rate (CPR), Ongoing Pregnancy Rates (OPR), and first-trimester miscarriage rates were observed across quartiles. The OPRs according to serum progesterone quartiles were: Q1: 57.5%; Q2: 62.6%; Q3: 59.6%; Q4:62.8%, with no statistical difference among the groups. Binary logistic regression revealed no statistically significant differences in clinical pregnancy and ongoing odds among the quartiles. Limitations, reasons for caution Although a prospective study, its relatively small sample size may affect the results’ robustness and generalizability. Wider implications of the findings These findings suggest that when using intramuscular progesterone before embryo transfer in FET under HRT, serum progesterone testing may not be necessary before embryo transfer, as progesterone levels have no impact on clinical outcomes in this group of patients. Trial registration number CTRI/2022/11/046995

Association between serum progesterone levels on the day of frozen-thawed embryo transfer and pregnancy outcomes after artificial endometrial preparation

BackgroundPrevious studies have examined that a range of optimal serum P level during the implantation period was associated with optimal live birth rates. However, those results obtained with vaginal or intramuscular route of progesterone administration for luteal phase support (LPS) alone. Is there a relationship between the serum progesterone (P) on the day of frozen-thawed embryo transfer (FET) with the likelihood of a live birth (LB) in artificial cycles (AC) when using a combination of oral dydrogesterone and vaginal progesterone for LPS?MethodsThis was a retrospective study of 3659 FET cycles with artificial endometrial preparation in a Chinese tertiary-care academic medical centre from January 2015 to February 2017. Endometrial preparation was performed using estradiol (E2) valerate (Fematon-red tablets) 8 mg/d beginning on day 3 of the cycle, followed by administration of P both orally (8 mg/d Fematon-yellow tablets) and vaginally (400 mg/d; Utrogestan). The primary endpoint was live birth rate (LBR). The association between the serum P level on the embryo transfer day and pregnancy outcomes was evaluated by univariable and multivariable logistic regression analysis.ResultsThe LBRs according to the serum P quartiles were as follows: Q1: 35.7%; Q2: 37.4%; Q3: 39.1% and Q4: 38.9%. Logistic regression analysis showed that the odds of a LB were not significantly different between the low (P < 7.9 ng/mL) and high (P ≥ 7.9 ng/mL) progesterone groups before or after adjustment (crude OR = 0.89, 95% CI: 0.76–1.04; adjusted OR = 0.89, 95% CI: 0.75–1.04).ConclusionThe present study suggests that the serum P levels on the day of embryo transfer (ET) do not correlate with the likelihood of a LB in artificial cycles when using a combination of oral dydrogesterone and vaginal progesterone for luteal phase support.

P-622 Clinical results in hormone replacement versus natural cycle protocols of endometrial preparation for frozen embryo transfer

Abstract Study question What is the optimal endometrial preparation protocol for a frozen embryo transfer (FET) with regards to clinical results? Summary answer A similar pregnancy and miscarriage rate is expected with either protocol of endometrial preparation for frozen embryo transfer. What is known already An optimal endometrial preparation for FET is of paramount importance to maximize ART success. However, the optimal endometrial preparation protocol for FET warrants more research and is pending to be determined. In addition, in studies that reviewed the optimal endometrial preparation protocols, few of them analyzed the stage and the number of embryos or other factors such PGT-A. Study design, size, duration Multicenter, retrospective cohort evaluation of FET cycles in a private center (August 2020-March 2021). The type of endometrial preparation regime (hormone replacement vs natural cycle) was analyzed according to the following variables: origin of the oocyte (own / donated), single-embryo-transfer, PGT-A, day of embryo development and progesterone values on the day or the day before the embryo transfer procedure. The core outcome variables were pregnancy rate (positive β-hCG), clinical pregnancy and miscarriage rate. Participants/materials, setting, methods 965 patients coming from autologous or heterologous cycles who performed FET. They were assigned to one group or another depending on the endometrial preparation regime used, either hormone replacement cycle (761) or natural cycle (204). The normality of the distribution of the variables was assessed using the Shapiro-Wilk test. The statistical analysis was carried out by T-Student (quantitative variables) or Chi-squared test (qualitative variables). Main results and the role of chance Statistically significant differences were found between the use of donated oocyte on natural cycle (41.7%) and hormone replacement cycle (55.7%) (p = 0.001). Furthermore, day 5 embryo transfer differed significantly between natural cycle (78.4%) and hormone replacement cycle (86.3%) (p = 0.029), as well as day 6 embryo transfer between natural cycle (21.1%) and hormone replacement cycle (12.5%) (p = 0.029). Likewise, mean progesterone value on the day of the embryo transfer was significantly higher in natural cycle (24.4 ng/mL) than in hormone replacement cycle (18.55 ng/mL) (p = 0.00). No statistically significant differences were found regarding pregnancy, clinical pregnancy and miscarriage rates between natural cycle (41.7, 31.9 and 23.1%) and hormone replacement cycle (44.7, 33.4 and 22.4%) (p = 0.48, 0.74 and 1.00), respectively. No significant differences were observed between the endometrial preparation regime regarding single-embryo-transfer and PGT-A (p &amp;gt; 0.05). Limitations, reasons for caution The inherent limitations of a retrospective study. Different routes of administration and doses of hormones were employed in the hormone replacement cycle. Similarly, natural cycles included: “true” and modified (hCG-triggered) cycles. Obstetric / perinatal outcomes were not evaluated. Wider implications of the findings Our results suggest no particular benefit of one protocol over the other in terms of clinical results. Nonetheless, the higher progesterone values detected in natural cycles might be clinically relevant in view of the positive correlation between P4 levels on the day of frozen-thawed embryo transfer (FET) with pregnancy outcomes. Trial registration number Not Applicable

Significance of endometrial thickness change after human chorionic gonadotrophin triggering in modified natural cycles for frozen-thawed embryo transfer.

BackgroundPeak endometrial thickness (EMT), measured on the end of follicular phase or early luteal phase, is the most widely used marker for endometrial receptivity during infertility treatment. However, the clinical significance of follicular-to-luteal EMT change remains unclear. We aimed to study whether the change of EMT between the day of human chorionic gonadotrophin (hCG) triggering and the day of frozen-thawed embryo transfer (FET) has any influence on pregnancy outcomes in modified natural cycles (mNCs).MethodsThis was a retrospective cohort study of 2,768 regular ovulatory women who underwent their first mNC-FET cycles from January 2011 to June 2015. Patients were divided into three groups according to the percentage change of EMT from the hCG triggering day to the FET day: >5% decrease (n=405), ±5% plateau (n=1,259) and >5% increase (n=1,104). The main outcome measure was live birth rate.ResultsLive birth rates were 41.9%, 39.8% [crude odds ratio (cOR) 0.91, 95% CI, 0.73–1.15) and 42.4% (cOR 1.02, 95% CI, 0.87–1.20) in the EMT plateau, decrease and increase groups, respectively (P=0.649). Multiple regression analysis did not alter the finding after controlling for a variety of confounders. Compared with the post-trigger EMT plateau group, the adjusted OR of live birth was 0.88 (95% CI, 0.69–1.12) in the decrease group and 1.05 (95% CI, 0.88–1.25) in the increase group. Similarly, no significant associations were observed before or after adjustment between EMT change and other pregnancy outcomes including positive hCG test, clinical pregnancy, early miscarriage and ongoing pregnancy.ConclusionsEMT change from hCG triggering to embryo transfer was not associated with pregnancy chances in mNC-FET cycles. This reassuring finding should provide guidance for physicians and patients when confronted with EMT decrease on the transfer day.

Effect of Endometrial Thickness Change in Response to Progesterone Administration on Pregnancy Outcomes in Frozen-Thawed Embryo Transfer: Analysis of 4465 Cycles.

ObjectiveTo evaluate whether endometrial thickness (EMT) change in response to progesterone has an effect on pregnancy outcomes in frozen-thawed embryo transfer (FET) cycles.DesignRetrospective observational study.SettingTertiary-care academic medical center.Participants4465 infertile women undergoing their first FET between January 2010 and December 2015 in our center.MethodsThis observational study included 4465 patients undergoing their first FET cycles between January 2010 and December 2015. EMT was measured by transvaginal ultrasound one day before progesterone administration and on the day of FET to observe EMT change.Main outcome measuresClinical pregnancy rate (CPR) and the live birthrate (LBR) was discussed.ResultsRegardless of the endometrial preparation protocols such as artificial cycle, estrogen-progesterone replacement therapy (EP) or natural cycle (NC), EMT may increase, decrease or remain stable on the day of FET compared with that of one day before progesterone administration. CPR in EMT increase, decrease and stable groups were 48.4%, 51.3% and 50.7% in EP cycle versus 49.2%, 52.0% and 48.9% in NC cycle, showing no significant difference between the three groups in both cycles (P= 0.48, P= 0.49). LBR was 40.9%, 45.9% and 42.6% in EP cycle versus 44.2%, 44.8% and 42.1% in NC cycle, also showing no significant difference between the three groups in both cycles (P= 0.16, P= 0.66). In addition, CPR and LBR were not significantly associated with EMT increase.ConcludesEMT may increase, decrease or remain stable on the day of FET as compared with that of one day before progesterone administration. Whatever change in EMT that occurs after progesterone administration has no significant effect on CPR and LBR in FET cycles.

Do serum progesterone levels on day of embryo transfer influence pregnancy outcomes in artificial frozen-thaw cycles?

The purpose of this study is to investigate whether progesterone (P4) levels on the day of frozen-thawed embryo transfer (FET) to a hormonally prepared endometrium correlate with pregnancy outcomes. This is a large retrospective cohort analysis comprising of N= 2010 FETs. In these cycles, P4 levels on the day of transfer were assessed in relation to pregnancy outcomes. A threshold of 10ng/mL was used to simulate currently accepted levels for physiological corpus luteal function. Biochemical pregnancy, clinical pregnancy, and live birth rates were compared between those with P4 levels above and below this threshold. Analyses using transfer day P4 thresholds of 5ng/mL and 20ng/mL were then completed to see if these could create further prognostic power. When comparing FET outcomes in relation to P4 levels < 10ng/mL and ≥ 10ng/mL, we observed no differences in biochemical pregnancy rates (39.53% vs. 40.98%, p= 0.52), clinical pregnancy rates (20.82 vs. 22.78, p= 0.30), and live birth rates (14.25 vs. 16.21 p= 0.23). In patients whose P4 met the threshold of 20ng/mL, there was similarly no statistically significant improvement in pregnancy outcomes. While there was no difference for biochemical or clinical pregnancy rates, a statistically significant improvement in live birth rates was observed for those with a transfer day P4 level ≥ 5ng/mL. We demonstrated that P4 levels at or above 10ng/mL on the day of FET do not confer a statistically significant improvement in pregnancy outcomes. P4 below 5ng/mg was associated with lower live birth rates suggesting that there is a threshold below which it is difficult to salvage FET cycles.

Luteal phase support does not improve the clinical pregnancy rate of natural cycle frozen-thawed embryo transfer: a retrospective analysis

ObjectiveTo evaluate pregnancy outcomes with and without use of luteal phase support (LPS) in frozen-thawed embryo transfer (FET) performed in natural cycles (NC). Study designRetrospective analysis. Before 1st July 2009, two doses of 1500IU intramuscular human chorionic gonadotrophin were given on the day of FET and 6 days after the transfer. Such practice was stopped after 1st July 2009. The pregnancy outcomes of NC FET with and without LPS were compared. ResultsA total of 408 NC FET cycles were analysed. Demographic data, embryo quality, clinical pregnancy rates and miscarriage rates were comparable with and without LPS. By univariate logistic regression, the only significant factors predicting the clinical pregnancy rate were the women's age, the number of embryos transferred, the number of top quality embryos before and after cryopreservation, and the average number of blastomeres after thawing. Only the women's age (OR 0.944, 95%C.I. 0.893–0.998, p=0.044) remained to be a significant predictor of clinical pregnancy rate by multivariate logistic regression. ConclusionThe pregnancy outcomes of NC FET were similar with or without LPS. The women's age was the significant factor affecting the clinical pregnancy rate. A randomised trial should be carried out to confirm the results.

Acupuncture for frozen–thawed embryo transfer cycles: a double-blind randomized controlled trial

The role of acupuncture on the pregnancy rate has not been evaluated in frozen-thawed embryo transfer (FET) cycles. This randomized double-blind study aimed to determine whether acupuncture performed on the day of FET improves clinical outcomes. On the day of FET, 226 patients were randomly allocated to either real or placebo acupuncture according to a computer-generated randomization list in sealed opaque envelopes. They received a session of real or placebo acupuncture for 25 min on site immediately after FET. The anxiety level and serum cortisol concentration were evaluated before and after real and placebo acupuncture. There were no significant differences in rates of overall pregnancy, clinical pregnancy, ongoing pregnancy, live birth and implantation in the placebo acupuncture group, when compared with the real acupuncture group. The anxiety level and serum cortisol concentration were similar for both groups. Only the placebo acupuncture group had significantly higher ongoing pregnancy (P=0.022) and implantation rates (P=0.038) than those who declined to join the study and received no acupuncture. In conclusion, comparable pregnancy and live birth rates of FET treatment were found in patients who had one session of real or placebo acupuncture after FET.

A randomized double-blind controlled study of the efficacy of laser-assisted hatching on implantation and pregnancy rates of frozen–thawed embryo transfer at the cleavage stage

Assisted hatching (AH) in fresh embryo transfer (ET) cycles increases the implantation and pregnancy rates, especially in women with a poor prognosis, repeated implantation failures and in older women. Little information exists in the literature regarding the role of AH in frozen-thawed embryo transfer (FET) cycles. Embryos were cryopreserved at the cleavage stage. On the day of FET, 160 patients were randomized according to a computer-generated randomization list in sealed envelopes into the AH group and the control group. The patients and the clinicians were blinded to the group assigned. In the AH group, the outer half of the zona pellucida over a quarter of the diameter of zona was removed using a 1480 nm non-contact laser. The two groups were comparable in terms of demographic characteristics, ovarian response of the stimulated cycle and quality of fresh and frozen-thawed embryos. No differences in implantation, pregnancy and multiple pregnancy rates were found between the two groups. There was a non-significant trend of a higher implantation rate in the AH group when the zona thickness was > or = 16 mm. Laser AH did not improve the implantation rate of FET cycles and should not be performed routinely in all frozen-thawed embryos at the cleavage stage.

The Relationship of Blood Progesterone and Estrogen Concentrations on the Day Before and the Day of Frozen-Thawed Embryo Transfer to Pregnancy Rate in Japanese Black Beef Cattle

The relationship of blood progesterone (P) and estradiol- 17β (E2) concentrations to the pregnancy rates in Japanese Black beef cattle recipients was investigated by determining blood P and E2 concentrations on the day before (day 6; day 0=onset of estrus) and the day of embryo transfer (day 7). Embryos were thawed by the stepwise method and transferred on day 7. The pregnancy rate showed a tendency toward increase with increasing P concentrations on both days 6 and 7 of embryo transfer. There was no significant correlation between the blood E2 concentration on day 6 and the pregnancy rate, wthereas pregnancy rate tended to rise when the blood E2 concentration on day 7 was low. The relationships of the blood E2/P ratio (× 103) on days 6 and 7 to the pregnancy rate were investigated. When the E2/P ratio was ≥1.0, the pregnancy rate tended to decrease. The bovine recipients, which showed poorly development CL, high blood E2/P ratio and coexistence of follicle ≥1.0 in diameter with CL, showed a tendency toward decrease in the pregnancy rate. From these observations, it is supposed to be important to select bovine recipient with the high bood P concentration and with the low blood E2 concentration on days 6 and 7 as bovine recipients for improvement of the pregnancy rate in bovine frozen-thawed embryo transfer.