Transfer Cycles Research Articles

Impact of vaginal microecological differences on pregnancy outcomes and endometrial microbiota in frozen embryo transfer cycles.

This prospective study investigates the correlation between vaginal microecology and pregnancy outcomes and explores their impact on endometrial microbiota composition during frozen embryo transfer (FET) cycles. Additionally, the impact of transvaginal Lactobacillus supplementation on reproductive outcomes in patients with previous failed cycles was assessed. A total of 379 patients undergoing FET at a reproductive medicine center were categorized into clinical pregnancy (CP), miscarriage (MISC), and non-pregnant (NP) groups. Vaginal specimens were collected for microecological evaluation prior to embryo transfer. Endometrial microbiota samples were obtained during embryo transfer for 16S rRNA gene sequencing analysis to assess endometrial microbiota composition. Vaginal microecological indicators, including pH, Lactobacillus dominance, and leukocyte esterase activity, were measured. Transvaginal Lactobacillus supplementation was investigated in 60 patients with previous failed cycles. Vaginal microecology significantly correlated with pregnancy outcomes, with normal microecology associated with a higher clinical pregnancy rate. Vaginal pH and leukocyte esterase activity were significantly associated with clinical pregnancy. Furthermore, vaginal microecological differences significantly impacted endometrial microbiota composition. However, no significant differences were observed in endometrial microbiota composition among the CP, MISC, and NP groups. Notably, transvaginal Lactobacillus supplementation increased the clinical pregnancy rate without affecting the miscarriage rate. This study highlights that normal vaginal microecology, characterized by lower pH and leukocyte esterase negativity, is associated with a higher likelihood of clinical pregnancy following FET. Importantly, vaginal microecological differences influence endometrial microbiota composition. Moreover, transvaginal Lactobacillus supplementation appears promising in improving clinical pregnancy rates in patients with previous failed cycles. These findings contribute to a better understanding of the interplay between vaginal and endometrial microbiota and offer potential interventions to enhance reproductive success in assisted reproductive technologies.

Effect of the time interval between denudation and ICSI on fresh embryo transfer reproductive outcomes: a retrospective study.

This study aims to determine if the incubation after oocyte denudation before Intra-cytoplasmic sperm injection (ICSI) affects the clinical pregnancy rate. This was a retrospective, consecutive data analysis of 1370 patients who underwent ICSI cycles at the Department of Reproductive Medicine of West China Second University of Sichuan University (Chengdu, Sichuan) between January 2020 and July 2022. The primary outcome was the clinical pregnancy rate. The second outcome included fertilization rate, biochemical pregnancy rate, and miscarriage rates. A total of 1370 continuous fresh transferred ICSI cycles were analyzed. Multivariate linear regression and logistic regression analysis of factors related to clinical pregnancy rates revealed that clinical pregnancy rates were significantly associated with denudation (DEN)-ICSI time interval. Long DEN-ICSI intervals are associated with a higher clinical pregnancy rate during fresh embryo transfer. The DEN-ICSI time interval is an independent factor for clinical outcomes in fresh ICSI transfer cycles.

Effect of frozen-thawed embryo transfer with a poor-quality embryo and a good-quality embryo on pregnancy and neonatal outcomes.

To evaluate the impact of embryo quality and quantity, specifically a poor quality embryo (PQE) in combination with a good quality embryo (GQE), by double embryo transfer (DET) on the live birth rate (LBR) and neonatal outcomes in patients undergoing frozen-thawed embryo transfer (FET) cycles. A study on a cohort of women who underwent a total of 1462 frozen-thawed cleavage or blastocyst embryo transfer cycles with autologous oocytes was conducted between January 2018 and December 2021. To compare the outcomes between single embryo transfer (SET) with a GQE and DET with a GQE and a PQE, propensity score matching (PSM) was applied to control for potential confounders, and a generalized estimating equation (GEE) model was used to determine the association between the effect of an additional PQE and the outcomes. Subgroup analysis was also performed for patients stratified by female age. After PS matching, DET-GQE + PQE did not significantly alter the LBR (adjusted odds ratio [OR] 1.421, 95% CI 0.907-2.228) compared with SET-GQE in cleavage-stage embryo transfer but did increase the multiple birth rate (MBR, [OR] 3.917, 95% CI 1.189-12.911). However, in patients who underwent blastocyst-stage embryo transfer, adding a second PQE increased the live birth rate by 7.8% ([OR] 1.477, 95% CI 1.046-2.086) and the multiple birth rate by 19.6% ([OR] 28.355, 95% CI 3.926-204.790), and resulted in adverse neonatal outcomes. For patients who underwent cleavage-stage embryo transfer, transferring a PQE with a GQE led to a significant increase in the MBR ([OR] 4.724, 95% CI 1.121-19.913) in women under 35 years old but not in the LBR ([OR] 1.227, 95% CI 0.719-2.092). The increases in LBR and MBR for DET-GQE + PQE compared with SET-GQE in women older than 35 years were nonsignificant toward. For patients who underwent blastocyst-stage embryo transfer, DET-GQE + PQE had a greater LBR ([OR] 1.803, 95% CI 1.165-2.789), MBR ([OR] 24.185, 95% CI 3.285-178.062) and preterm birth rate (PBR, [OR] 4.092, 95% CI 1.153-14.518) than did SET-GQE in women under 35 years old, while no significant impact on the LBR ([OR] 1.053, 95% CI 0.589-1.884) or MBR (0% vs. 8.3%) was observed in women older than 35 years. The addition of a PQE has no significant benefit on the LBR but significantly increases the MBR in patients who underwent frozen-thawed cleavage-stage embryo transfer. However, for patients who underwent blastocyst-stage embryo transfer, DET-GQE + PQE resulted in an increase in both the LBR and MBR, which may lead to adverse neonatal outcomes. Thus, the benefits and risks of double blastocyst-stage embryo transfer should be balanced. In patients younger than 35 years, SET-GQE achieved satisfactory LBR either in cleavage-stage embryo transfer or blastocyst-stage embryo transfer, while DET-GQE + PQE resulted in a dramatically increased MBR. Considering the low LBR in women older than 35 years who underwent single cleavage-stage embryo transfer, selective single blastocyst-stage embryo transfer appears to be a more promising approach for reducing the risk of multiple live births and adverse neonatal outcomes.

A comparative analysis of the clinical pregnancy and perinatal outcomes between oocyte vitrification and embryo vitrification based on the propensity score matching method.

This study investigated the safety and effectiveness of oocyte vitrification by comparing the clinical pregnancy and perinatal outcomes between transfer cycles of vitrified oocytes and those of vitrified embryos. A retrospective cohort study was conducted to analyze the clinical data of patients who underwent cleavage-stage embryo transfer at the Department of Reproductive Medicine between January 2011 and June 2021. Seventy-seven transfer cycles of fresh cleavage-stage embryos developed from vitrified-thawed oocytes (oocyte vitrification group) and 2170 transfer cycles of vitrified-thawed cleavage-stage embryos developed from fresh oocytes (embryo vitrification group) were included. Further, 293 cases were selected from the embryo vitrification group after applying propensity score matching at 1:4. The primary outcomes were miscarriage rate, live birth rate, and neonatal birth weight. No statistically significant differences were observed in the baseline data, pregnancy, perinatal outcomes, or neonatal outcomes for either singleton or twin births between the two groups after matching. Backwards stepwise regression was used to analyze the length of gestation. The age of female participants (β = - 0.410, 95% CI = - 1.339 ~ - 0.620, P < 0.001) had a statistically significant effect. Oocyte vitrification results in similar clinical pregnancy and perinatal outcomes as does embryo vitrification; hence, it is a relatively safe assisted reproductive technique.

Serum uric acid did not affect embryonic and pregnancy outcomes in women without PCOS during IVF procedures.

Serum uric acid (UA) levels are associated with many systemic diseases. A previous study confirmed the association between high serum uric acid levels and poor prognosis of in vitro fertilization (IVF) treatment in polycystic ovary syndrome (PCOS) patients. This study aimed to explore the correlation between serum uric acid levels and reproductive outcomes in patients without PCOS. A retrospective study that included 1057 patients who underwent pre-implantation genetic testing for monogenic disorders (PGT-M) treatment from January 2013 to December 2020 was conducted. The study population was further divided into 3 groups according to serum UA levels: the ≤250 μmol/L group, the 251-360 μmol/L group, and the >360 μmol/L group. The controlled ovarian hyperstimulation (COH) treatment outcomes, embryonic treatment outcomes and pregnancy outcomes of the first frozen embryo transfer (FET) cycle were compared among groups. Multivariable linear regression and binary regression were applied to detect the association between IVF outcomes and serum uric acid levels. The number of retrieved oocytes, fertilization rate, viable embryo rate, blastocyst formation rate and euploid rate were not associated with serum uric acid levels. The mature oocyte rate was negatively correlated with serum uric acid levels. The pregnancy outcomes of the first FET cycle were also not associated with serum uric acid levels. After adjustment for BMI, the perinatal outcomes were not associated with serum uric acid levels. IVF treatment outcomes were not associated with serum uric acid levels in patients without PCOS.

Sequential embryo transfer combined with intrauterine perfusion improved pregnancy outcomes in patients with recurrent implantation failure

ObjectiveTo compare the application of sequential embryo transfer, cleavage embryo transfer, and blastocyst transfer combined with intrauterine perfusion in frozen–thawed embryo transfer cycles in patients with recurrent implantation failure to provide a reference for reproductive clinicians.MethodsThe 166 patients who underwent frozen–thawed embryo transfer due to recurrent implantation failure in the reproductive center from January 2021 to March 2022 were retrospectively analyzed. According to the different embryos transferred, they were divided into cleavage embryo transfer groups (72 cases in Group A), blastocyst transfer group (29 cases in Group B), and sequential transfer group (65 cases in Group C). All three groups were treated with intrauterine perfusion 5 days before embryo transfer. The general data and clinical pregnancy outcome indicators, such as embryo implantation rate, clinical pregnancy rate, ongoing pregnancy rate, live birth rate, twin rate, were compared among the three groups.ResultsThe embryo implantation rate (53.1%), clinical pregnancy rate (76.9%), ongoing pregnancy rate (67.7%) and live birth rate(66.15%) in the sequential transfer group were significantly higher than those in the other two groups (P < 0.05), and the ectopic pregnancy rate was lower in the sequential transfer group.ConclusionSequential transfer combined with intrauterine perfusion partially improves clinical pregnancy outcomes and reduces the risk of ectopic pregnancy in frozen embryo cycle transfers in patients with recurrent implantation failure, which may be a favourable transfer reference strategy for patients with recurrent implantation failure.

BDS-3 six-frequency precise point positioning: effects of receiver-dependent inter-frequency clock bias and multi-frequency contributions

We find that there is time-varying bias at the receiver in BDS-3 multi-frequency phase observations, which will lead to receiver-dependent inter-frequency clock bias (RIFCB) and damage the rigor of BDS-3 multi-frequency precise point positioning (PPP) model. A unified RIFCB correction method compatible with uncombined and ionospheric-free combined PPP models using any BDS-3 frequencies is proposed. The contributions of multi-frequency integration to BDS-3 static and kinematic PPP performance are evaluated. The results indicate that the RIFCB amplitude can reach 1 dm. If the RIFCB correction is ignored, the phase observation residuals present a systematic bias. RIFCB has potential effects on precise time transfer, ionospheric monitoring, and fractional cycle bias estimation. Experimental results show that the long-term frequency stability of time transfer can be improved by correcting RIFCB. The joint use of all BDS-3 six-frequency signals can significantly shorten the convergence time, and the positioning accuracy can also be slightly improved.

The reproductive potential of vitrified-warmed euploid embryos declines following repeated uterine transfers

BackgroundRecurrent implantation failure (RIF) represents a vague clinical condition with an unclear diagnostic challenge that lacks solid scientific underpinning. Although euploid embryos have demonstrated consistent implantation capabilities across various age groups, a unanimous agreement regarding the advantages of preimplantation genetic testing for aneuploidy (PGT-A) in managing RIF is absent. The ongoing discussion about whether chromosomal aneuploidy in embryos significantly contributes to recurrent implantation failure remains unsettled. Despite active discussions in recent times, a universally accepted characterization of recurrent implantation failure remains elusive. We aimed in this study to measure the reproductive performance of vitrified-warmed euploid embryos transferred to the uterus in successive cycles.MethodsThis observational cohort study included women (n = 387) with an anatomically normal uterus who underwent oocyte retrieval for PGT-A treatment with at least one biopsied blastocyst, between January 2017 and December 2021 at a university-affiliated public fertility center. The procedures involved in this study included ICSI, blastocyst culture, trophectoderm biopsy and comprehensive 24-chromosome analysis of preimplantation embryos using Next Generation Sequencing (NGS). Women, who failed a vitrified-warmed euploid embryo transfer, had successive blastocyst transfer cycles (FET) for a total of three using remaining cryopreserved euploid blastocysts from the same oocyte retrieval cycle. The primary endpoints were sustained implantation rate (SIR) and live birth rate (LBR) per vitrified-warmed single euploid embryo. The secondary endpoints were mean euploidy rate (m-ER) per cohort of biopsied blastocysts from each patient, as well as pregnancy and miscarriage rates.ResultsThe mean age of the patient population was 33.4 years (95% CI 32.8–33.9). A total of 1,641 embryos derived from the first oocyte retrieval cycle were biopsied and screened. We found no associations between the m-ER and the number of previous failed IVF cycles among different ranges of maternal age at oocyte retrieval (P = 0.45). Pairwise comparisons showed a significant decrease in the sustained implantation rate (44.7% vs. 30%; P = 0.01) and the livebirth rate per single euploid blastocyst (37.1% vs. 25%; P = 0.02) between the 1st and 3rd FET. The cumulative SIR and LBR after up to three successive single embryo transfers were 77.1% and 68.8%, respectively. We found that the live birth rate of the first vitrified-warmed euploid blastocyst transferred decreased significantly with the increasing number of previously failed IVF attempts by categories (45.3% vs. 35.8% vs. 27.6%; P = 0.04). A comparable decrease in sustained implantation rate was also observed but did not reach statistical significance (50% vs. 44.2 vs. 37.9%; P = NS). Using a logistic regression model, we confirmed the presence of a negative association between the number of previous IVF failed attempts and the live birth rate per embryo transfer cycle (OR = 0.76; 95% CI 0.62–0.94; P = 0.01).ConclusionsThese findings are vital for enhancing patient counseling and refining management strategies for individuals facing recurrent implantation failure. By tailoring interventions based on age and ovarian reserve, healthcare professionals can offer more personalized guidance, potentially improving the overall success rates and patient experiences in fertility treatments.Trial registration numberN/A.

Single Euploid Embryo Transfer Outcomes After Uterine Septum Resection

ObjectiveTo study pregnancy outcomes after single euploid embryo transfer (SEET) in patients who underwent prior uterine septum resection to those with uteri of normal contour, without Müllerian anomalies or uterine abnormalities including polyps or fibroids, and without a history of prior uterine surgeries. DesignRetrospective cohort study SettingSingle academic affiliated center Patients60 cycles of patients with prior hysteroscopic uterine septum resection who underwent an autologous SEET between 2012-2020 were used as the investigational cohort. A 3:1 ratio propensity score matched control cohort of 180 single euploid embryo transfer cycles from patients without a history of uterine septa were used as the control group. Intervention(s)No interventions administered. Measurements and Main ResultsPregnancy, clinical pregnancy loss, ongoing clinical pregnancy, and live birth rates in patients with history of uterine septum resection compared to matched patients without Müllerian anomalies or uterine surgeries. Patients with a prior uterine septum had significantly lower rates of chemical pregnancy (58.33% vs 77.2%, p=0.004), implantation (41.67% vs 65.6%, p=0.001), and live birth (33.33% vs 57.8%, p=0.001) per transfer. No statistical difference in clinical pregnancy loss rates was found when comparing septum patients with controls (8.33% vs 7.8%, p=0.89). ConclusionPatients with history of hysteroscopic resection who undergo in vitro fertilization are more susceptible to suboptimal clinical outcomes compared to patients with normal uteri. Early pregnancy loss rates in patients with a uterine septum are higher than in those without, however, after resection, the rates are comparable. Patients born with septate uteri require assessment of surgical intervention prior to SEET and to optimize their reproductive outcomes.

Effect of male HBV infection on the outcomes of IVF/ICSI cycles: a retrospective cohort study based on propensity score matching.

This study aimed to investigate the effects of male hepatitis B virus (HBV) infection on male fertility, embryonic development, and in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes. We performed a retrospective cohort study that included 3965 infertile couples who received fresh embryo transfer cycles for the first time at the Fujian Maternity and Child Health Hospital (Fuzhou, China) from January 2018 to January 2021. Infertile couples were categorized based on their HBV infection status into the HBV group (HBV-positive men and HBV-negative women) and the control group (HBV-negative couples). A 1:1 propensity score matching was performed with relatively balanced covariates. Baseline characteristics, semen parameters, laboratory outcomes, clinical outcomes, and obstetric and neonatal outcomes were compared between groups. After propensity score matching, 821 couples were included in each group. Both groups had similar semen parameters and obstetric and neonatal outcomes. The HBV group showed a significantly lower live birth rate than the control group ( P < 0.05). The HBV group had a significantly higher abortion rate than the control group ( P < 0.05). The rates of high-quality embryos and blastocyst formation were significantly lower in the HBV group than those in the control group (both P < 0.05). In conclusion, in couples who undergo IVF/ICSI, male HBV infection reduces the live birth rate and increases the risk of miscarriage. However, the incidence of low birth weight in women with IVF/ICSI does not increase with male HBV infection.

Progesterone concentrations on blastocyst transfer day in modified natural cycle frozen embryo transfer cycles

Research questionAre serum progesterone concentrations on the day of modified natural cycle (mNC) frozen blastocyst transfer (FET) without luteal phase support (LPS) associated with clinical pregnancy rate (CPR)? DesignData were collected between January 2019 and October 2022 as a sub-study of an ongoing randomized controlled trial assessing pregnancy outcomes in mNC-FET. The sub-study included all women (n = 209) randomized to mNC-FET without LPS at the time of data extraction. Participants were aged 18–41 years, had regular menstrual cycles and underwent mNC-FET treatment with single-blastocyst transfer. Associations between the serum progesterone concentration on the day of blastocyst transfer and CPR, pregnancy rate and pregnancy loss rate (PLR) were examined between groups with low and higher progesterone concentrations using the 25th and 10th percentiles as cut-offs. Multivariate logistic regression analyses were performed to adjust for potential confounding factors. ResultsProgesterone concentrations on the day of blastocyst transfer in mNC-FET without LPS ranged from 4.9 to 91.8 nmol/l, with the 25th and 10th percentiles at 29.0 nmol/l and 22.5 nmol/l, respectively. Serum progesterone concentrations did not differ between women with or without a clinical pregnancy (mean [SD] 38.5 [14.0] versus 36.8 [12.4] nmol/l; P = 0.350). Furthermore, the CPR, pregancy rate and PLR were similar in women with low or high progesterone concentrations when using the 25th or the 10th progesterone percentile as cut-off. Multivariate regression analyses showed no association between progesterone concentrations and CPR. ConclusionsNo association was found between progesterone concentration on the day of blastocyst transfer and pregnancy outcome in women undergoing mNC-FET without progesterone LPS.

Prioritized single vitrified blastocyst to be warmed between grades 3 or 4 blastocyst on day 5 transfer cycles.

Selecting the optimal blastocyst to implant during cryopreservation and warming is critial for in vitro fertilization success. Therefore, the aim of this study was to explore which blastocyst should be prioritized to be thawed when facing a single vitrified blastocyst on day 5 transfer. A retrospective study including 1,976 single vitrified-warmed blastocyst transfer cycles was conducted from January 2016 to December 2020. We found that grade 4 vitrified blastocyst had a higher clinical pregnancy (60.64% vs. 49.48%, P < 0.001) and live birth rates (50.12% vs 39.59%, P < 0.001) than the grade 3 vitrified blastocyst. However, no statistical difference was found between groups in miscarriage rate, birth weight, or gestational age. Besides, the grade 4 vitrified-thawed blastocyst had significant potential to develop into grade 6 blastocyst after further culturing for 16 h (73.68% vs. 48.60%, P < 0.001). The grade 6 transferred blastocyst was markedly higher in both clinical pregnancy rate (61.88% vs. 51.53%, P < 0.001) and live birth rate (50.91% vs. 40.46%, P < 0.001) compared to grade 5 transferred blastocyst. Grade 4 vitrified blastocyst is recommended when facing single vitrified blastocyst on day 5 transfer. More importantly, the "embryonic escape hypothesis" was firstly proposed to reveal the findings.

Ultrafast spin dynamics in magnetic trimer and tetramer clusters: a step towards prototypic spin-SHIFT registers

Ultrafast magnetic dynamics is a necessary ingredient for magnetic recording and ultrafast information processing. The shift functionality, although not mandatory for Boolean logic, is always implemented in CMOS CPUs and therefore must be also present in magnetic logic. In this respect, using ab initio calculations we show ultrafast spin dynamics in molecular clusters such as Co3 +CO and Ni4. In this work, we establish that clusters with magnetic atoms can provide a theoretical toolbox for efficient spin charge dynamics whose operation time can range up to a few picoseconds. The prime underlying mechanism for all spin manipulation scenarios in the above mentioned clusters are laser-induced Λ processes where the laser parameters are fully optimized using a genetic algorithm. In general, a structural asymmetry enforces substantial spin localization on the active centers of both magnetic clusters. Keeping in mind the shift functionality, we theoretically suggest a series of spin-transfer scenarios between the Co and Ni atoms in each of these two clusters independently to construct a 3-bit and a 4-bit cyclic spin-SHIFT register, respectively. The maximum operational time for both logic devices is 2 ps, which is much faster than the response time of conventional spintronic devices. Additionally, for a better understanding of the transfer cycles, their feasibility and reversibility are also investigated through the analysis of the optical spectra of the related states. Our results provide important theoretical guidance for ultrafast spin manipulation in molecular structures as well as their potential spin functionality, and thus step closer to the realization of future spin-based logic devices and quantum computation. This effectively motivates the investigation and precise establishment of the shift functionality in magnetic trimers and tetramers.

Does The Culture of Post-Thawed Cleavage-Stage Embryos to Blastocysts Improve Infertility Treatment Outcomes of Frozen-Thawed Embryo Transfer Cycles? A Randomised Clinical Trial.

There is a definite shift in assisted reproductive centres from cleavage-stage embryo transfer (ET) to blastocyst transfer that is attributed to improvements in laboratory environments and advances in the development of embryo culture media. The aim of the study was to investigate the reproductive outcomes of thawed cleavage-stage ET versus blastocysts derived from an extended culture of these embryos. This open-label, randomised, parallel group clinical trial study enrolled 182 women aged ≤37 years who underwent frozen-thawed ET from November 2015 to June 2020 at Royan Institute Research Centre, Tehran, Iran. The women were randomly assigned to either the thawed cleavage ET group (n=110) or the post-thaw extended culture blastocysts group (n=72). The primary outcome measure was the clinical pregnancy rate. Secondary outcome measures were implantation rate, live birth rate (LBR), and miscarriage rate. A P<0.05 indicated statistical significance. There were no significant differences between the two groups in terms of demographic characteristics. Both the mean numbers of embryos transferred and good quality embryos transferred were significantly lower in the postthaw extended culture blastocysts group compared to thawed cleavage-stage ET cycles. However, the post-thaw extended culture blastocysts group had higher clinical pregnancy (56.94 vs. 40.91%, P=0.034), implantation (34.43 vs. 19.84%, P=0.001) and live birth (49.3 vs. 33.63%, P=0.036) rates compared to the thawed cleavage-stage ET group. Miscarriage and multiple gestations rates were comparable between the groups. These results allow us to take a position in favour of post-thaw extended culture blastocysts; thus, it is important to improve the post-thawing extended culture technique (registration number: NCT02681029).

Fertilization, pregnancy, and neonatal outcomes after IVF, rescue ICSI, and ICSI in unexplained infertility: A retrospective study

AbstractConventional intracytoplasmic sperm injection (ICSI) is not recommended for nonmale infertile patients to avoid fertilization failure (FF) in view of controversies regarding safety issues. Among the strategies that may help to promote the use of in vitro fertilization (IVF) for women with a high risk of FF, rescue ICSI (R‐ICSI) has attracted attention. This study aimed to evaluate the efficacy of short‐term insemination combined with early R‐ICSI in the treatment of unexplained infertility. A total of 952 controlled ovarian stimulation (COS) cycles for unexplained infertility were divided into short‐term IVF (short‐term insemination without R‐ICSI, n = 500), R‐ICSI (short‐term insemination with R‐ICSI, n = 141), and ICSI (conventional ICSI, n = 311) groups. Patients underwent consecutive transfer cycles until live birth, or until all embryos from the first COS cycle were used. Laboratory data and clinical outcomes from short‐term IVF, R‐ICSI, and ICSI groups were compared. Short‐term IVF and ICSI groups were superior to R‐ICSI group in polyspermy rate, available embryo rate, and top‐quality embryos rate. Short‐term IVF, R‐ICSI, and ICSI groups underwent 705 (500 fresh and 205 frozen‐thawed cycles), 190 (141 fresh and 49 frozen‐thawed cycles), and 445 (311 fresh and 134 frozen‐thawed cycles) transfer cycles, resulting in 294, 76, and 190 live birth cycles, respectively. Comparison of pregnancy outcomes among these three groups demonstrated similar clinical pregnancy rates and live birth rates in fresh and frozen‐thawed embryo transfer cycles. There was no significant difference in the cumulative live birth rate among these three groups. R‐ICSI group showed similar neonatal outcomes compared with short‐term IVF and ICSI groups, including the rates of low birth weight, fetal macrosomia, small for gestational age and large for gestational age. Short‐term insemination combined with early R‐ICSI achieved satisfactory pregnancy and neonatal outcomes, albeit with a high polyspermy rate, which was an effective alternative to avoid excessive use of ICSI in unexplained infertility.

Dissecting host-microbiome interaction effects on phytoplankton microbiome composition and diversity.

Phytoplankton and their associated microbiomes of heterotrophic bacteria are foundational to primary production, energy transfer, and biogeochemical cycling in aquatic systems. While it is known that these microbiomes are shaped by host-released dissolved organic matter (DOM), the extent to which dynamic phytoplankton-bacteria interactions shape bacterial community assembly remains to be examined. Here, we investigated the effects of two mechanisms in host-microbiome interactions on phytoplankton bacterial microbiome formation: (i) innate host selection and (ii) host-microbiome feedback. For the former, phytoplankton-produced DOM composition is based solely on the host's properties (species or physiological state); for the latter, the presence of the microbiome modifies host DOM production. The microbiome of Chlorella sorokiniana was extracted and exposed to six ratios of the two effects. We found that microbiome composition changed along with the six host-microbiome feedback versus innate host selection ratios, with the highest compositional distance between communities under the strongest and the weakest ratio of the two effects. This indicates that each mechanism selects for different bacterial species. In addition, our findings showed that when both selective forces were applied, it led to a higher community richness, while host-microbiome feedback alone reduces community evenness due to its strong species-specific selection.

Heterotopic pregnancy after a single embryo transfer with successful perinatal outcome: case report and literature review

A heterotopic pregnancy is a rare and serious pathological pregnancy. In this paper, we report a rare case of heterotopic pregnancy and perform a literature review. A 30-year-old patient with a history of left adnexectomy presented with persistent lower abdominal pain and hemorrhagic shock after single embryo transfer. Emergency laparoscopic exploration revealed a ruptured mass in the right isthmus of the fallopian tube, for which right salpingectomy was performed. After anti-inflammatory treatment and fetal preservation, the intrauterine pregnancy progressed smoothly, and a healthy baby was delivered at 39 weeks gestation. In this case, the patient’s heterotopic pregnancy was possibly due to a natural pregnancy caused by sexual intercourse during treatment, so we recommend that sexual intercourse be avoided during transfer cycles.

Effect of Low-Quality Embryo on Adverse Obstetric and Perinatal Outcomes

Background: This retrospective study focused on whether low-quality embryos have the risk on perinatal and obstetric outcomes. Methods: This study enrolled 600 women undergoing fresh embryos transfer (ET) cycles between June 2019 and December 2022. The patients were stratified into two groups, high-quality embryo group and low-quality embryo group. In both groups, the perinatal and obstetric outcomes were the primary outcomes. Moreover, we conducted a multi-variable logistic regression analysis, where additional possible confounding factors were controlled, to determine how diverse embryo qualities affected the primary outcomes. Results: The results showed that compared with the low-quality group, the high-quality group showed increased clinical pregnancy (63.33% vs 26.33%) as well as a higher number of live birth rates (52.67% vs 18.33%) (P＜0.001). There were no statistically significant differences in unfavorable perinatal and obstetric outcomes between high- and low-quality groups (p＞0.05). Similarly, the transfer of blastocysts developing from high-quality embryos led to increased clinical pregnancy rates (84.50% vs 48.05%, p&lt;0.001) and live birth rates (74.64% vs 38.96%, p&lt;0.001). Transfer of blastocysts developing from low-quality embryos did not impact the unfavorable perinatal or obstetric outcomes. The logistic regression analysis showed that low-quality could not increase the unfavorable perinatal or obstetric outcomes. Conclusion: In summary, low-quality ET does not increase the risk of unfavorable perinatal or obstetric outcomes. Overall, compared to low-quality embryos, the transfer of high-quality embryos increases the clinical pregnancy and live birth rates.

Does embryo biopsy, independent of vitrification, impact perinatal outcomes? An analysis of perinatal outcomes following preimplantation genetic testing biopsy in fresh and frozen embryo transfer cycles

Does embryo biopsy, independent of vitrification, impact perinatal outcomes? An analysis of perinatal outcomes following preimplantation genetic testing biopsy in fresh and frozen embryo transfer cycles

Survey on the implementation status and reproductive outcomes of oocyte and ovarian tissue cryopreservation in Japan: Historical comparison with nationwide surveys.

To clarify the reproductive outcomes of fertility preservation (FP) treatment. We conducted a mailed-in questionnaire survey at institutions certified by the Japan Society of Obstetrics and Gynecology to investigate the number of oocyte cryopreservations (OC) and ovarian tissue cryopreservations (OTC) performed from December 2016 to the end of 2020. And, we conducted a detailed investigation of cases in which frozen specimens were used during the investigation period, and made historical comparisons with previous nationwide studies. Responses were received from 114 out of 150 facilities (response rate: 76.0%) for OC and 43 out of 51 for OTC (response rate: 84.3%). Breast cancer was the most common disease among patients whose FP specimens were used. During the study period, 1237 OCs and 198 OTCs were performed. In addition, 57 cycles of embryo transfer (ET) using cryopreserved oocytes and 12 cases of ovarian tissue transplantation (OTT) were performed. The mean age of patients who underwent ET using cryopreserved oocytes was 34.8 (±5.8) years, with a median age of 36 years. The pregnancy rate per ET using cryopreserved oocytes was 26.3% and the live birth rate (LBR) was 17.5%. Further, the LBR per patient was 43.3%, and the pregnancy rate following OTTs was 33.3%. Also, controlled ovarian stimulation using the random start method or the combination of aromatase inhibitors had no effect on pregnancy outcome. Implementation of both OCs and OTCs have markedly increased over time in Japan, with comparable reproductive outcomes as other reports.