Frozen-thawed Single Embryo Transfer Research Articles

Effects of high-normal fasting blood glucose on ART outcomes of frozen-thawed single blastocyst transfer in women with normal BMI.

This retrospective cohort study aims to investigate whether high-normal fasting blood glucose (FBG) affects assisted reproductive technology (ART) outcomes undergoing single blastocyst frozen-thawed embryo transfer (FET) cycles in women with normal body mass index (BMI). 944 women with normal BMI and FBG levels undergoing single blastocyst FET cycles were enrolled. Based on the median of FBG (4.97mmol/L, 1mmol/L = 18mg/dL), the subjects were categorized into the low-normal group (3.90 ≤ FBG ≤ 4.97 mmol/L, n = 472) and the high-normal group (4.97 < FBG < 6.10mmol/L, n = 472). Multivariable logistic regression and receiver operating characteristic (ROC) were used to analyze the relationship between high-normal FBG and ART outcomes. live birth rate (LBR). LBR was significantly lower in the high-normal group than in the low-normal group (36.8% vs. 45.1%, p = 0.010), and the miscarriage rate was considerably higher than that in the low-normal group (23.9% vs. 16.5%, p = 0.041). High-normal FBG of female was an independent predictor of live birth (adjusted OR:0.747, 95% CI: 0.541-0.963, p = 0.027) and miscarriage (adjusted OR:1.610, 95% CI: 1.018-2.547, p = 0.042). ROC analyses showed that the cut-off values of FBG (endpoints: live birth and miscarriage) were 5.07mmol/L, and 5.01mmol/L, respectively. In women with normal BMI, high-normal FBG is an independent risk factor for lower LBR and higher miscarriage rate in single blastocyst FET cycles. Attention to preconception FBG monitoring in this particular population may allow early intervention to improve ART outcomes.

P-553 Embryo collection improves clinical pregnancy outcomes in next-generation sequencing(NGS)-based preimplantation genetic testing for aneuploidy (PGT-A) euploid embryo transfers

Abstract Study question Is there still a significant impact of embryo-related characteristics on pregnancy rates in NGS based PGT-A euploid embryo transfers for advanced-age patients? Summary answer In single frozen euploid embryo transfers, priority of embryo transfer and grade significantly influence clinical pregnancy rates in women over 35 years old with PGT-A. What is known already It is widely recognized that better embryo grades and a shorter duration of blastulation are associated with favorable reproductive outcomes. Recent meta-analyses have affirmed these findings even in the context of transfer with euploid embryos. However, the impact of prioritizing the highest-ranked embryo among multiple vitrified euploid embryos on pregnancy rates remains unclear. The lack of research in this area implies a gap in understanding whether selecting embryos for transfer among multiple viable euploid embryos could enhance reproductive success. Study design, size, duration Throughout the year 2022, a retrospective review was conducted on 428 cycles of single frozen-thawed euploid embryo transfers performed at a single institution, targeting patients aged 35 and older. The study aimed to explore potential differences in clinical pregnancy rates based on embryo grade, embryo freezing date, and embryo selection priority. Participants/materials, setting, methods Women ≥ 35 years old with single frozen euploid blastocyst transfer cycles was categorized into three groups: (a) with one blastocyst (1/1), (b) with ≥ two blastocysts having the top-priority(½ or higher), and (c) lower-priority blastocysts (lower than ½) to examine potential differences in clinical pregnancy rates among groups based on embryo characteristics, including Gardner grading and day of embryo freezing. Results highlight the impact of both selection criteria and freezing conditions on pregnancy outcomes. Main results and the role of chance This study analyzed a total of 428 frozen embryo transfer (FET) cycles. In the context of frozen-thawed single embryo transfer, the clinical pregnancy rate was 52.2% (128/245) when only one euploid embryo was frozen and subsequently thawed for transfer (a). For cases where two or more euploid embryos were frozen, and embryos with a higher priority (½ or higher) were selected for transfer (b), the clinical pregnancy rate significantly increased to 71.3% (62/87). Conversely, when embryos with a lower priority (lower than ½ in order) were chosen for transfer (c), the clinical pregnancy rate was lower at 38.5% (15/38), indicating a statistically significant difference between the groups (p = 0.001). Categorizing embryos based on Gardner grading, “good” embryos (&amp;gt;3BB) demonstrated a clinical pregnancy rate of 66.8% (141/211), while embryos with lower quality (3BB or below) showed a significantly lower clinical pregnancy rate of 40.6% (88/217) (p &amp;lt; 0.001). The analysis of clinical pregnancy rates based on the embryo freezing day revealed significant differences among embryos freezing on 5 days (71.9%, 133/185), 6 days (39.9%, 71/178), 7 days (25%, 2/8), and thawing PGT-A embryos (38.2%, 21/55) (P &amp;lt; 0.001). Limitations, reasons for caution One limitation of this study is its retrospective nature, and the potential confounding effect of the close association between embryo selection and embryo grading. Further analysis will be conducted to confirm correlations and address this potential confounding effect. Wider implications of the findings In single euploid frozen embryo transfers, selecting the highest-quality embryo through careful embryo selection remains relevant. Morphological indicators of embryos significantly impact early pregnancy outcomes, highlighting the continued importance of strategic embryo accumulation for enhanced procedural success. Trial registration number not applicable

Racial disparities in the outcomes of euploid single frozen-thawed embryo transfer cycles – analysis of the Clinical Outcome Reporting System of the Society for Assisted Reproductive Technology 2016–2018 data

ObjectiveTo evaluate if in pregnancies conceived with the transfer of single genetically tested embryos, maternal race and ethnicity relate to pregnancy outcome. DesignRetrospective cohort. SubjectsAutologous frozen -thaw embryo transfer (FET) cycles with transfer of single genetically tested embryo in SART-CORS for years 2016-2018; cycles associated with diagnoses of recurrent pregnancy loss, gestational carrier, donor egg and donor embryo were excluded. ExposureInformation on race and ethnicity linked with in vitro fertilization and FET cycles available in the SART-CORS. Main Outcome MeasuresMultivariable analyses utilizing generalized estimating equation examined the relationship between categories of race and ethnicity with the following outcomes: Pregnancy (+βhCG following FET), clinical pregnancy, pregnancy loss (early [at gestation <13 weeks] and late [loss between ≥13 and <20 weeks]), preterm (<37 weeks), term (≥37 weeks) and live birth. Covariates adjusted for included age, BMI, AMH, infertility diagnosis and smoking history. Results79,416 FET cycles met the eligibility criteria. Information on race and ethnicity was specified for 50,820 (64.0%) and was not known in 28, 723 (36%) of the cycles . The population was predominantly non-Hispanic White (NHW, 44%). Non-Hispanic Black [NHB] comprised 2.7%, Asian 12.3%, Hispanic 3.4%, American Indian, Pacific Islander, Hawaiian and Alaskan [AI_AL_PI_H] 0.2%. Nearly 1.0 % self-identified with more than one race. On multivariable analyses, pregnancies in NHB and in Hispanic women (compared to NHWs) were significantly more likely to result in in preterm birth (p<0.001). Compared to NHW women, the likelihood of live birth was significantly lower in NHBs (p<0.01), Asian (p=0.04), Hispanic (<0.01) and AI_AL_PI_H women (p<0.01). . The likelihood for delivery by Cesarean was also disproportionately higher in the NHB (p=0.047), Hispanic (p=0.007) and in women identifying with more than one race (0.023)compared to NHWs . ConclusionRacial and ethnic differentials are apparent in the outcomes of FET conceived pregnancies resulting from the transfer of single genetically tested embryos.

Primary omental ectopic pregnancy after frozen-thawed single embryo transfer: A case report and review of the literature

Primary omental ectopic pregnancy after frozen-thawed single embryo transfer: A case report and review of the literature

Individualized luteal phase support in frozen-thawed embryo transfer after intramuscular progesterone administration might rectify live birth rate.

The serum P concentrations are suggested to have an impact on pregnancy outcome. However there is no consensus about the optimal progesterone cut-off during the luteal phase. Few studies evaluated the effectiveness of a "rescue protocol" for low serum P concentrations and most of these studies used vaginal progesterone administration. There is paucity of data on the effectiveness of rescue protocol using intramuscular progesterone (IM-P) in frozen-thawed embryo transfer (FET). This study is a retrospective cohort study included 637 single or double blastocyst FETs with artificially prepared endometrium receiving 100 mg IM progesterone (P) after incremental estrogen treatment. Serum P concentrations were evaluated using blood samples obtained 117-119 hours after the first IM-P administration and 21 ± 2 hours after the last IM-P administration. Patients with serum P concentrations <20.6 ng/ml on the ET day were administrated 400 mg vaginal progesterone for rescue. Demographic and cycle characteristics were similar between patients receiving rescue vaginal P (embryo transfer (ET)-day P concentration < 20.6 ng/ml) and patients who did not need rescue vaginal P (ET-day P concentration ≥ 20.6 ng/ml). Clinical pregnancy, miscarriage, and live birth rates were similar between two groups: 52.9%(45/85) vs 59.6%(326/552), p=0.287; 11.1%(5/45) vs 14.1%(46/326), p=0.583; and 47.1%(40/85) vs 50.7%(280/552), p=0.526, respectively. Logistic regression analysis revealed that the female age (p = 0.008, OR=0.942, 95% CI = 0.902-0.984) and embryo quality (ref: good quality for moderate: p=0.02, OR=0.469, 95% CI =0.269-0.760; for poor: p=0.013, OR= 0.269, 95% CI = 0.092-0.757) were independent variables for live birth. Following rescue protocol implementation, ET-day P concentration was not a significant predictor of live birth. Rescue vaginal P administration for low ET day serum P concentrations following IM-P yields comparable live birth rates.

Reproductive outcomes of single frozen-thawed embryo transfer in patients with endometriosis after preimplantation genetic testing.

The reproductive outcomes of patients with endometriosis who are infertile have attracted recent attention. We aimed to explore whether endometriosis affects endometrial receptivity by observing pregnancy outcomes following a euploid blastocyst frozen embryo transfer. This retrospective cohort study analyzed the data of patients with endometriosis from the reproductive hospital affiliated to Shandong University between January 2015 and December 2021. Control groups were matched using the 1:3 propensity score. The live birth, clinical pregnancy, biochemical pregnancy, clinical abortion, premature birth, and aneuploid rates were compared between the control group and endometriosis group. A total of 625 patients who underwent preimplantation genetic testing (PGT) prior to embryo implantation were included in the analysis. There were no significant differences in the live birth, clinical pregnancy, biochemical pregnancy, clinical abortion, and premature birth rates between the two groups. The aneuploidy rate of blastocysts obtained from the endometriosis group was higher than that of the control group (P = 0.012). Pregnancy outcomes using frozen embryos after PGT in patients with endometriosis did not differ from those in other women experiencing infertility. However, endometriosis may affect the quality of oocytes, resulting in a higher rate of aneuploidy.

#276 : Impact of Previous Cesarean Delivery on Pregnancy and Neonatal Outcomes of Subsequent In Vitro Fertilization/Intracytoplasmic Sperm Microinjection and Single Frozen-Thawed Embryo Transfer

Background and Aims: Cesarean delivery (CD) rates continue to rise worldwide. Prior studies have indicated that CD is associated with not only various gynaecological symptoms and obstetric complications but also lower probability of subsequent fertility. However, the recognition about impact of CD on clinical outcomes in subsequent IVF/ICSI-FET is very limited. The purpose was to investigate the effects of previous CD on pregnancy and neonatal outcomes in single frozen-thawed embryo transfer (FET) cycles so that women with a previous cesarean delivery can be given detailed fertility counseling during the ART process. Methods: This is a large retrospective cohort study including a total of 5,750 patients who desired to transfer single vitrified-thawed blastocyst from the same oocyte retrieval cycle as their last live birth between January 2011 and January 2021 in a center for reproductive medicine in Shandong, China, comprising FET cycles of 3,853 previous single CD and 1,897 previous single vaginal delivery (VD). Results: Women with a previous CD had significantly lower rates of biochemical pregnancy (64.52% vs. 71.48% before propensity score matching (PSM), P&lt;0.001; and 65.58% vs. 71.49% after PSM, P&lt;0.001), clinical pregnancy (58.16% vs. 65.79% before PSM, P&lt;0.001; and 59.22% vs. 66.17% after PSM, P&lt;0.001) and live birth (48.17% vs. 55.82% before PSM, P&lt;0.001; and 49.29% vs. 56.10% after PSM, P&lt;0.001) than those with a previous VD. Meanwhile, the CD rate was significantly higher in the CD group (97.85% vs. 18.53% before PSM, P&lt;0.001; and 98.02% vs. 20.51% after PSM, P&lt;0.001). The rates of multiple pregnancy, miscarriage, ectopic pregnancy, multiple live birth, labor complications and preterm and neonatal outcomes were comparable between the two groups. Conclusion: Compared to VD, a previous CD is associated with a significant reduction in the rates of biochemical pregnancy, clinical pregnancy and live birth in patients undergoing subsequent single frozen-thawed blastocyst transfer.

Impact of Lactobacillus in the uterine microbiota on in vitro fertilization outcomes

Abundant intrauterine Lactobacillus is associated with good in vitro fertilization (IVF) outcomes; however, whether specific species of Lactobacillus have any benefit remains unclear. So we examine the effect of Lactobacillus on the clinical outcomes of IVF at the species level. Uterine microbiota were classified as either Lactobacillus-dominant (LD) or non-Lactobacillus-dominant. In the LD group, we further investigated the clinical results for each Lactobacillus species and evaluated them in relation to IVF outcomes. In Uterine microbiome analysis, Lactobacillus was the most abundant, with the four species of L. crispatus, L. iners, L. gasseri, and L. jensenii accounting for the great majority. We compared the clinical outcomes of single frozen-thawed embryo transfer conducted by Lactobacillus species and found that the implantation rate was lowest in those in whom L. iners was dominant. This study is the first to conduct a species-level analysis of the uterine microbiota and report on a detailed investigation of Lactobacillus, which was believed to be particularly helpful for pregnancy.

O-050 The impact of embryo biopsy on obstetric and neonatal outcomes

Abstract Background Preimplantation genetic testing of embryos (PGT) was performed first in 1990 to prevent the transmission of X-linked disease. Since then, the technique has improved to include couples who are both carriers of the same autosomal recessive disorder, to those with balanced translocations having recurrent pregnancy loss, and to women with advanced maternal age who are at higher risk for having aneuploid embryos. Originally, PGT involved biopsy of the polar body or of one blastomere of a cleavage stage embryo for diagnosis. The contemporary practice of PGT involves the culture of embryos to the blastocyst stage (5-7 days after fertilization), with biopsy of several trophectoderm cells that would become the placenta, transport of biopsy tissue off-site for genetic analysis, and cryopreservation of blastocysts until biopsy results are available. A single euploid embryo is then transferred into the uterus as a frozen embryo transfer. Objective We sought to determine if removal of these cells for preimplantation genetic testing was associated with adverse obstetrical or neonatal outcomes after frozen-thawed single embryo transfer compared to frozen-thawed single embryo transfer without biopsy. Further, we review other studies of contemporary practice of PGT to draw conclusions about the safety of the practice. Study design We linked assisted reproductive technology surveillance data from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System to birth certificates and maternal and neonatal hospitalization discharge diagnoses in Massachusetts, USA, from 2014-2017, considering singleton births after frozen-thawed single embryo transfer. We compared outcomes of cycles having embryo biopsy (n = 585) to those having no biopsy (n = 2,191), adjusting for mother’s age, race, education, parity, body mass index, birth year, insurance, and all infertility diagnoses (Sites CK et al, Am J Obstet Gynecol 2021;225:285.e1-7). Results With no biopsy used as the reference, we found no differences between no biopsy and biopsy groups with respect to preeclampsia, pregnancy-induced hypertension, placental disorders (placental abruption, placenta previa, placenta accreta, placenta increta, and placenta percreta), preterm birth, low birthweight, cesarean delivery, gestational diabetes mellitus, or maternal or infant length of stay after delivery. Comparing our outcomes to 4 other studies of contemporary PGT practice of frozen-thawed embryo transfers (Zhang WY Fertil Steril 2019, Li M Am J Obstet Gynecol 2020, Makhijani R Hum Reprod 2021, He H Fertil Steril 2019), our data are consistent with no effect of biopsy on low birth weight, pregnancy-induced hypertension, gestational diabetes, placenta previa, and placenta accreta. A slight decrease in preterm delivery (RR 1.10, CI 1.02-1.18), slight reduction in cesarean section (RR 0.90, CI 0.82-0.99), and increase in intrauterine growth restriction (RR 1.21, CI 1.06-1.38) are reported with biopsy in a systematic review (Hou W, Fertil Steril 2021). The increase in risk for intrauterine growth restriction with biopsy was influenced by one study (Li M Am J Obstet Gynecol 2020). Conclusion Embryo biopsy of trophectoderm cells for PGT in contemporary practice appears to be safe generally with respect to maternal and neonatal outcomes. There is no clear increase in diagnoses related to placentation (preeclampsia, pregnancy-induced hypertension, placental disorders, preterm birth, low birthweight), cesarean delivery, gestational diabetes mellitus, or maternal or infant length of stay after delivery. Further study of a possible increase in intrauterine growth restriction with biopsy is indicated.

P-542 How should we prepare the endometrium in euploid embryo transfer cycles? Modified natural or artificial endometrial preparation?

Abstract Study question Does modified natural endometrial preparation in single euploid frozen-thawed embryo transfer (FET) cycles affect chance of pregnancy and risk of miscarriage compared to artificial? Summary answer The rate of clinical pregnancy and live birth increases while the rate of miscarriage decreases in modified natural FET cycles compared to artificial FET cycles. What is known already Corpus luteum produces growth factors, angiogenic factors and vasoactive substances as well as hormones. These substances play role for initial placentation. Early maternal endocrine milieu resulting exogenous estrogen and progesterone could damage placentation, which may in turn cause miscarriage. High estradiol levels might also be responsible for decreased pregnancy rates (Wu et al 2021). Study design, size, duration This retrospective, single center study evaluated 1890 frozen single euploid embryo transfer cycles in women between 20-43 years old from January 2017 to September 2021. The study is based on data obtained from Istanbul Memorial Hospital, ART and Reproductive Genetics Center. FET cycles were analyzed in two groups according to different endometrial preparation protocol. Group A (n = 1335): modified natural FET cycles (mNat/FET) and Group B (n = 555): artificial FET cycles (AC-FET). Participants/materials, setting, methods Only good prognosis patients with ages between 20-43 years old were included. Exclusion criterias were women age 44 and above, recurrent abortion history, BMI&amp;gt;35 kg/m 2, endometrial factor, uterin factor (adenomyosis, mullerian anomaly) history. NGS was used to study trophoectoderm biopsy material in all cases. Patients demographics, cycle characteristics and pregnancy outcomes were analyzed. Main results and the role of chance We analyzed the effect of endometrial preparation methods on pregnancy outcomes between the two groups after excluding confounding factors in single euploid embryo transfer cycles. There were no significant differences in patient demographics and cycle characteristics such as age, body-mass index, infertility duration, previous IVF attempts, AMH level, daily gonadotropin dosage used, number of oocytes obtained, mature oocytes and fertilized oocytes between the two groups. There was no significant difference between the morphologic grading of the transferred embryos in both groups. However, all pregnancy outcomes were statistically significantly different in two groups. In group A, biochemical pregnancy rate (76.9% vs. 73.9%, p:0.04), clinical pregnancy rate (71% vs. 65.7%, p &amp;lt; 0.01), live birth rate (65.4% vs. 50.5%, p &amp;lt; 0.01) were significantly higher than in group B. Also, biochemical pregnancy loss rate (7.7% vs. 11%, p:0.01), clinical pregnancy loss rate (6.7% vs. 21%, p &amp;lt; 0.01), second trimester pregnancy loss rate (0.8% vs. 1.5%, p:0.04) were significantly lower compared to group B. Limitations, reasons for caution The limitation of our study include the fact that this was a retrospective analysis. Prospective randomised studies are necessary to evaluate the differences between the two groups according to pregnancy outcomes. Wider implications of the findings This study shows that pregnancy outcomes are better in patients undergoing mNat/FET even after controlling for confounding factors when comparing mNat/FET and AC-FET in single euploid FET cycles. As a result, in appropriate patients, mNat/FET with higher pregnancy rate and live birth rate should be preferred as much as feasible. Trial registration number Not applicable

Preimplantation genetic testing for aneuploidy and chromosomal structural rearrangement: A summary of a nationwide study by the Japan Society of Obstetrics and Gynecology.

The Japan Society of Obstetrics and Gynecology conducted a nationwide clinical study to evaluate the pregnancy outcomes of preimplantation genetic testing for aneuploidy or chromosomal structural rearrangement (PGT-A/SR). Patients that had experienced recurrent implantation failure, recurrent pregnancy loss, or chromosomal structural rearrangement were recruited from 200 fertility centers in Japan. For patients in whom one or more blastocysts were classified as euploid or euploid with suspected mosaicism, a frozen-thawed single embryo transfer (ET) was performed. A total of 10 602 cycles, maternal age 28-50 years, were enrolled in this study. 42 529 blastocysts were biopsied, and 25.5%, 11.7%, and 61.7% of embryos exhibited euploidy, mosaicism, and aneuploidy, respectively. At least one euploid blastocyst was obtained in 38.3% of egg retrieval cycles with embryo biopsy. A total of 6080 ETs were carried out, and the clinical pregnancy rate per ET, ongoing pregnancy rate per ET, and miscarriage rate per pregnancy were 68.8%, 56.3%, and 10.4%, respectively. The rates of clinical pregnancy and miscarriage remained relatively constant across all maternal ages. Preimplantation genetic testing for aneuploidy or chromosomal structural rearrangement may improve the pregnancy rate per ET and reduce the miscarriage rate per pregnancy, especially in patients of advanced maternal age.

İmplantasyon Başarısızlığı Olan Hastalarda Donmuş Embriyo Transferi Öncesi Histeroskopik Cerrahinin Etkisi

Aim: The aim of this study was to evaluate the benefit of hysteroscopy (HS) before single frozen-thawed embryo transfer (sFET) on patients with previous implantation failure. Material and Methods: A total of 1352 infertile women with a previous implantation failure who underwent their first sFET treatment between January 2015 and December 2017 were included in this study. The patients were classified into two main groups in which HS was omitted (Group 1), and who underwent HS (Group 2). Furthermore, Group 2 was classified into two subgroups as patients without any intrauterine pathology (Group 2a), and those with intrauterine pathology (Group 2b). sFET was performed on all patients within 50 days of hysteroscopy. The major outcome measure was the clinical pregnancy rate. Results: The mean number of mature oocytes and fertilization rates were similar between groups. The clinical pregnancy rate was found to be 33.3% (n=70) in Group 1. Comparatively this rate was statistically significantly higher in patients in Group 2. The clinical pregnancy rate was 44.2% (n=378) in Group 2a, and 44.4% (n=127) in Group 2b (p=0.014). There was a significant difference between Group 1 and Group 2a (OR: 1.58, 95% CI: 1.15-2.17, p=0.004), and also Group 2b (OR: 1.59, 95% CI: 1.10-2.31, p=0.013). However, no significant difference was observed between Group 2a and Group 2b (p=0.896). Conclusion: Our findings demonstrate that HS surgery increases the probability of pregnancy rate at least by 1.58 times in patients having previous implantation failure when the hysteroscopic procedure is followed by sFET.

P-395 Use of a granulocyte-macrophage colony-stimulating factor (GM-CSF)-containing medium for poor-grade blastocyst transfer increases the clinical pregnancy and live birth rates

Abstract Study question Does the post-thaw use of a GM-CSF-containing medium improve blastocyst transfer outcomes in all blastocysts in a frozen-thawed embryo transfer cycle? Summary answer The use of a GM-CSF-containing medium at post-thawing especially improves the live birth (LB) rate of morphologically poor blastocysts in a frozen-thawed embryo transfer cycle. What is known already GM-CSF, a cytokine secreted by the epithelial cells of the female reproductive tract, plays an important role in embryonic development, implantation, and subsequent development in humans and animals. In humans, GM-CSF increases the blastocyst developmental rate and decreases the chances of miscarriage. Previously, we reported that the use of a GM-CSF-containing medium for blastocyst recovery culture after thawing improves the clinical pregnancy (CP) rate in a frozen-thawed blastocyst transfer cycle (ESHRE, 2019). However, it is unclear whether GM-CSF improves embryo transfer outcomes in all blastocysts. In addition, it is necessary to accumulate information regarding its effects on neonatal outcomes. Study design, size, duration We performed a retrospective observational study to compare two groups: a GM-CSF group (GM-CSF-containing medium; SAGE-1step GM-CSF, Cooper Surgical) and a control group (GM-CSF-free medium; ONE STEP Medium, NAKA Medical). We analyzed 566 blastocyst transfer cycles in patients aged 30–39 years who underwent frozen-thawed single embryo transfer at Takahashi Women’s Clinic (Japan) from February 2018 to February 2019. Chromosomal analysis was not performed. Participants/materials, setting, methods We used a control medium for blastocyst culture and a Cryotop safety kit for blastocyst vitrification. After thawing, we cultured blastocysts in a GM-CSF-containing medium or control medium for 3–5 h until transfer. Embryo transfer outcomes were compared. We performed the multivariate logistic regression analysis(MVRA) to adjust confounding bias. A subgroup analysis was also performed of morphological grade according to Gardner’s criteria (excellent: ≥AA, good: blastocysts containing B, poor: blastocysts containing C). Main results and the role of chance There were no difference in patient background between the two groups. The CP and LB rates in the GM-CSF group and control group were 54.3% vs. 42.6% and 42.9% vs. 31.1%. The MVRA adjusted by confounding factors(patient age, BMI, basal AMH, blastocyst grade, day of vitrification, number of previous failed ETs, and assisted hatching) demonstrated that CP (p = 0.0193; adjusted odds ratio [aOR], 1.55) and LB rate (p = 0.0080; aOR, 1.67) were significantly higher in GM-CSF group than that of control group. Moreover, the CP and LB rates of the GM-CSF group and control group were: excellent-blastocysts at 62.0% vs. 58.8% (p = 0.5955; OR, 1.14), 52.7% vs. 45.6% (p = 0.2466, aOR:1.33), good-blastocysts 52.1% vs. 37.6% (p = 0.0561; OR, 1.80), 38.0% vs. 26.6% (p = 0.1072; OR, 1.69), and poor-blastocysts 38.9% vs. 17.9% (p = 0.0115; OR, 2.92), 25.9% vs. 9.0% (p = 0.0164; OR, 3.56). A GM-CSF-containing medium significantly improved the CP and LB rates of poor-grade blastocysts. There were no significant differences between the GM-CSF group and control group in the male ratio (52.7％ vs. 51.0%, p = 0.8057), pregnancy duration (38.8±1.4 weeks vs. 38.5±1.8 weeks, p = 0.2558), cesarean section rate (38.2% vs. 40.8%, p = 0.6979), birth weight (3133±466g vs. 3037±437g, p = 0.1281), and congenital anomaly rate (0.91% vs. 2.04％, p = 0.6026). Limitations, reasons for caution This was a single-center, retrospective study. Chromosomal abnormalities in embryos were not considered; however, the LB rate among babies was analyzed. The basic chemical composition of the culture medium (salt concentration, glucose concentration, etc.) used in the control group was different from that of the GM-CSF-containing medium. Wider implications of the findings We found that the use of a GM-CSF-containing medium improved the clinical pregnancy and live birth rates of poor-grade blastocysts without affecting the babies. This may be an effective therapeutic strategy for some patients as it may allow for the effective use of poor-grade euploid blastocysts. Trial registration number not applicable

The impact of blastomere loss on pregnancy and neonatal outcomes of vitrified-warmed Day3 embryos in single embryo transfer cycles

BackgroundBlastomere loss is a common phenomenon that occurs following cryopreservation. To date, studies have drawn conflicting conclusions regarding the impact of blastomere loss on pregnancy outcomes. Besides, limited information is available concerning the neonatal safety of embryos with blastomere loss. In the present study, we aimed to investigate the impact of blastomere loss on pregnancy and neonatal outcomes of vitrified/warmed Day3 cleavage-stage embryos in single embryo transfer cycles.MethodsThis retrospective cohort study included all vitrified/warmed D3 cleavage-stage single frozen-thawed embryo transfer (FET) cycles between April 2015 and February 2021. We compared pregnancy and subsequent neonatal outcomes between the intact embryos group and the blastomere loss group in single FET cycles.ResultsA total of 6287 single FET cycles were included in the study, in which 5873 cycles were classified into the intact embryo group and 414 cycles were classified into the blastomere loss group. The outcomes of the blastomere loss group were significantly inferior to those of the intact embryo group, in terms of implantation/biochemical pregnancy/clinical pregnancy/ongoing pregnancy rate and live birth rate per embryo transfer cycle/per clinical pregnancy. Further binary logistic regression confirmed that blastomere loss was negatively associated with live birth. Moreover, the blastomere loss group presented with an elevated early miscarriage rate. The neonatal conditions were broadly similar between the two groups. Additionally, multiple binary logistic regression analysis demonstrated that primary infertility and intracytoplasmic sperm injection (ICSI) were common influencing factors of blastomere loss (aOR 1.447, 95% CI 1.038–2.019, P = 0.029; aOR: 1.388, 95% CI: 1.044–51.846, P = 0.024).ConclusionsThe transfer of vitrified/warmed D3 embryos with blastomere loss is related to impaired embryo developmental potentials and reduced probabilities of conception. Moreover, even if the embryos with blastomere loss have implanted and reached clinical pregnancies, they present with a lower possibility of developing to live birth owing to a higher early miscarriage rate. However, once the embryos with blastomere loss result in a live birth, no adverse neonatal outcomes are observed.Primary infertility and ICSI were found to be risk factors for blastomere loss.

Assisted reproductive technologies in Latin America: the Latin American Registry, 2019

Research questionWhat was the utilization, effectiveness and safety of assisted reproductive technology (ART) in Latin America during 2019? DesignThis was a retrospective collection of multinational data on ART performed at 196 institutions from 15 countries. ResultsA total of 106,918 initiated cycles, 18,133 deliveries and 21,096 births were reported. ART utilization was 24–558 cycles per million inhabitants. Women aged ≥40 years represented 32.9% of fresh IVF and intracytoplasmic sperm injection (ICSI) cycles. After removing freeze-all cycles, the delivery rate per oocyte retrieval was 17.3% for ICSI and 19.5% for IVF. Overall, single-embryo transfer (SET) represented 36.2% of fresh transfers, with a 19.5% delivery rate per transfer, increasing to 30.7% for elective SET and 32.7% for blastocyst elective SET (eSET). The delivery rate for double-embryo transfers (DET) was 27.8%, increasing to 37.1% after elective DET. This 6.4% increment in deliveries between eSET and elective DET resulted in a 12-fold increase in twin births. Furthermore, overall perinatal mortality was more than two-fold higher for twin compared with singleton deliveries. The delivery rate for frozen-thawed SET reached 28.1%, most being blastocyst transfers. Of all births, 72.3% were singletons, 26.4% twins and 1.3% triplets and higher multiples. Preterm deliveries reached 14.3% for singletons and 58.1% for twins. Perinatal mortality was 7.4‰ in singletons, 17.2‰ for twins and 62.9‰ for triplets or higher. ConclusionsThe number of initiated cycles has slowly increased in countries with laws or regulations facilitating access. FET cycles predominate and blastocyst SET are also increasing. The data show that, especially in young women and oocyte recipients, when there is more than one blastocyst for transfer, eSET should be the rule.

Assisted reproductive technologies in Latin America: the Latin American Registry, 2019.

What was the utilization, effectiveness and safety of assisted reproductive technology (ART) in Latin America during 2019? This was a retrospective collection of multinational data on ART performed at 196 institutions from 15 countries. A total of 106,918 initiated cycles, 18,133 deliveries and 21,096 births were reported. ART utilization was 24-558 cycles per million inhabitants. Women aged ≥40 years represented 32.9% of fresh IVF and intracytoplasmic sperm injection (ICSI) cycles. After removing freeze-all cycles, the delivery rate per oocyte retrieval was 17.3% for ICSI and 19.5% for IVF. Overall, single-embryo transfer (SET) represented 36.2% of fresh transfers, with a 19.5% delivery rate per transfer, increasing to 30.7% for elective SET and 32.7% for blastocyst elective SET (eSET). The delivery rate for double-embryo transfers (DET) was 27.8%, increasing to 37.1% after elective DET. This 6.4% increment in deliveries between eSET and elective DET resulted in a 12-fold increase in twin births. Furthermore, overall perinatal mortality was more than two-fold higher for twin compared with singleton deliveries. The delivery rate for frozen-thawed SET reached 28.1%, most being blastocyst transfers. Of all births, 72.3% were singletons, 26.4% twins and 1.3% triplets and higher multiples. Preterm deliveries reached 14.3% for singletons and 58.1% for twins. Perinatal mortality was 7.4‰ in singletons, 17.2‰ for twins and 62.9‰ for triplets or higher. The number of initiated cycles has slowly increased in countries with laws or regulations facilitating access. FET cycles predominate and blastocyst SET are also increasing. The data show that, especially in young women and oocyte recipients, when there is more than one blastocyst for transfer, eSET should be the rule.

The identification of endometrial immune cell densities and clustering analysis in the mid-luteal phase as predictor for pregnancy outcomes after IVF-ET treatment

Changes in endometrial immune cell density has been reported to be associated with reproductive failure. The prognostic value of endometrial immune cell density measurement remains uncertain. We aimed to investigate the prognostic value of endometrial immune cells measurement on pregnancy outcome after IVF in women. In this prospective study, one hundred twenty-eight women underwent endometrial sampling in a natural cycle preceding single frozen-thawed embryo transfer (ET). Endometrial biopsy was obtained precisely 7 days after luteinizing hormone surge (LH + 7). Multiplex immunohistochemical method was employed to simultaneously stain the endometrium samples with a panel of human antibodies against CD56 for uterine natural killer (uNK) cells, CD3 and CD8 for T cell, CD3 for pan T cells and CD68 for macrophages. The density of the various immune cells and the clustering levels between them were measured. ET was performed at the blastocyst stage. Women who did not conceive had a significantly higher density of uNK cells and higher clustering level between uNK cells-and-macrophages than women who did conceive. In accordance, the prognostic value of uNK measurement on pregnancy outcome was significantly improved when combined with uNK-to-macrophage clustering analysis simultaneously. Taken together, our results suggested that uNK cells density and clustering level between uNK cells-and macrophages may be a promising predictor for successful implantation after IVF-ET.

Embryo biopsy and maternal and neonatal outcomes following cryopreserved-thawed single embryo transfer

Contemporary embryo biopsy in the United States involves the removal of several cells from a blastocyst that would become the placenta for preimplantation genetic testing. Embryos are then cryopreserved while patients await biopsy results, with transfers occurring in a subsequent cycle as a single frozen-thawed embryo transfer, if euploid. We sought to determine if removal of these cells for preimplantation genetic testing was associated with adverse obstetrical or neonatal outcomes after frozen-thawed single embryo transfer. We linked assisted reproductive technology surveillance data from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System to birth certificates and maternal and neonatal hospitalization discharge diagnoses in Massachusetts from 2014 to 2017, considering only singleton births after frozen-thawed single embryo transfers. We compared outcomes of cycles having embryo biopsy (n=585) to those having no biopsy (n=2191) using chi-square for categorical and binary variables and logistic regression for adjusted odds ratios and 95% confidence intervals, adjusting for mother's age, race, education, parity, body mass index, birth year, insurance, and all infertility diagnoses. Considering no biopsy as the reference, there was no difference between groups with respect to preeclampsia (adjusted odds ratio, 0.82; 95% confidence interval, 0.42-1.61; P=.5685); pregnancy-induced hypertension (adjusted odds ratio, 0.85; 95% confidence interval, 0.46-1.59; P=.6146); placental disorders, including placental abruption, placenta previa, placenta accreta, placenta increta, and placenta percreta (adjusted odds ratio, 1.16; 95% confidence interval, 0.60-2.24; P=.6675); preterm birth (adjusted odds ratio, 1.22; 95% confidence interval 0.73-2.03; P=.4418); low birthweight (adjusted odds ratio, 1.12; 95% confidence interval, 0.58-2.15; P=.7355); cesarean delivery (adjusted odds ratio, 1.04; 95% confidence interval, 0.79-1.38; P=.7762); or gestational diabetes mellitus (adjusted odds ratio, 0.83; 95% confidence interval, 0.50-1.38; P=.4734). In addition, there was no difference between the groups for prolonged hospital stay for mothers (adjusted odds ratio, 1.23; 95% confidence interval, 0.83-1.80; P=.3014) or for infants (95% confidence interval, 1.29; 95% confidence interval, 0.72-2.29; P=.3923). Embryo biopsy for preimplantation genetic testing does not increase the odds for diagnoses related to placentation (preeclampsia, pregnancy-related hypertension, placental disorders, preterm delivery, or low birthweight), maternal conditions (gestational diabetes mellitus), or maternal or infant length of stay after delivery.

The Morphology of Inner Cell Mass Is the Strongest Predictor of Live Birth After a Frozen-Thawed Single Embryo Transfer.

BackgroundThe scoring system for human blastocysts is traditionally based on morphology; however, there are controversies on the effect of morphology parameters on pregnancy outcomes. The aim of this study is to evaluate the predicting value of each morphology parameter on pregnancy outcomes in a setting of single embryo transfer.MethodsThis is a retrospective cohort study on patients undergoing frozen-thawed single blastocyst transfer at our center, between Jan. 2009 and Dec. 2018. A total of 10,482 cycles were analyzed. The blastocysts were scored according to the expansion and hatching status, morphology of inner cell mass (ICM), and cells of trophectoderm (TE). The primary outcome measure was live birth rate. One-way analysis of variance, chi-square test, and multiple logistic regression were used for statistical analysis.ResultsThe clinical pregnancy rate was lower in the blastocysts of stage 3 (48.15%), compared with those of stage 4 (56.15%), stage 5 (54.91%), and stage 6 (53.37%). The live birth rate was lower in the blastocysts of stage 3 (37.07%), compared with those of stage 4 (44.21%) and stage 5 (41.67%). The rates of clinical pregnancy (A: 66.60%, B: 53.25%, C: 39.33%) and live birth (A: 54.62%, B: 41.29%, C: 28.45%) were both decreased with decreasing grade of ICM morphology, and these differences were pairwise significant. The miscarriage rate of blastocysts with ICM grade A was lower, compared with ICM grade C (17.53 vs. 27.66%). Blastocysts with TE morphology of C had lower rates of clinical pregnancy (43.53%) and live birth (32.57%), compared with those with TE morphology of A and B (clinical pregnancy rate: 64.26% for A, 58.11% for B; live birth rate: 52.74% for A, 45.64% for B). There were no significant differences in rates of clinical pregnancy, live birth, and miscarriage between the blastocysts with TE grade A and B.ConclusionsThe blastocyst expansion stage, ICM grade, and TE grade are all associated with pregnancy outcomes. ICM grade is the strongest predictor of live birth. A blastocyst with stage 4–5, ICM grade A, and TE grade A/B should be given priority for single embryo transfer.

Association between morphologic grading and implantation rate of Euploid blastocyst

BackgroundStandard morphologic evaluation has been the most widely adopted approach to embryo selection, and remains the most common strategy.The objective of the study to determine the association between the morphologic grading and implantation rate of euploid blastocysts in single frozen-thawed embryo transfer (SET) cycles.MethodsA total of 271 patients aged 20–40 years undergoing euploid SET from January 2017 to December 2019 were included in retrospective cohort study.The cycles were divided into three groups based on their morphologic grading before cryopreservation: good-quality (n = 58), average-quality (n = 88) and poor-quality blastocysts (n = 125). The pregnancy outcome of the three morphologic groups were analyzed and a logistic regression of implantation rate was conducted.ResultsGood-quality blastocysts yielded statistically significantly higher implantation rates than poor-quality (79.31% vs. 48%; P<0.001). Planned subgroup analyses by age and the day of TE biopsy were conducted. Logistic regression analyses that adjusted for these variables identified higher implantation rates (adjusted odds ratio(aOR) = 4.083, 95% confidence interval (CI):1.836–9.082, P<0.001) for the good-quality blastocysts than for those that underwent poor-quality cycles in women aged < 35 years, but not in women aged ≥35 years (aOR = 6.074, 95% CI: 0.456–80.919, P = 0.172). The implantation rates were higher among women with good-quality blastocysts on both Day 5 and Day 6 of TE biopsy than among those with poor-quality blastocysts (Day 5, aOR = 3.294, 95% CI:1.260–8.616, P = 0.015; Day 6, aOR = 4.179, 95% CI:1.004 ~ 17.399, P = 0.049). Day 5 euploid blastocysts had no significant difference in implantation potential and early spontaneous abortion rate compared with similarly graded Day 6 euploid blastocysts.ConclusionsBlastocyst morphologic grading was associated with implantation rate for euploid embryo transfers after adjustment for potential confounders. These findings suggest that evaluating blastocyst morphology is critical when selecting the best euploid blastocyst.