UNASSIGNED: Studies on the effect of vaccine type and two other vaccines other than inactivated vaccines approved in China on in vitro fertilization (IVF) pregnancy outcomes are rare. To complement and confirm the existing findings, this research aimed to investigate whether there are adverse effects of different vaccine types in females and males on reproductive function and clinical pregnancy.
UNASSIGNED: This retrospective study enrolled 6,455 fresh embryo transfer cycles at the First Affiliated Hospital of Zhengzhou University between May 1, 2021, and October 31, 2022. The primary outcome is the clinical pregnancy rate (CPR). At the same time, the secondary results are the number of oocytes retrieved, two pronuclei (2PN) rate, blastocyst formation rate, high-quality blastocyst rate, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DNA fragment index (DFI) rate).
UNASSIGNED: In the comparison of ovarian stimulation indicators, no statistically significant differences (P > 0.05) were found in Gn days, endometrial thickness, 2PN rate, metaphase 2 (MII) rate, high-quality embryo rate, and blastocyst formation rate. No significant differences (P>0.05) were found in age, body mass index (BMI), education level, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DFI rate) in these four groups. The multivariate regression model showed that neither the types of vaccines nor the vaccination status of both infertile couples significantly affected clinical pregnancy.
UNASSIGNED: The type of vaccine does not appear to have an unfavorable effect on ovarian stimulation, embryo development, semen parameters, and clinical pregnancy.

OBJECTIVE: Can pregnancy outcomes following fresh elective single embryo transfer (eSET) in gonadotropin-releasing hormone (GnRH) antagonist protocols increase using a gonadotropin (Gn) step-down approach with cessation of GnRH antagonist on the day of hCG administration (hCG day) in patients with normal ovarian response?
CONCLUSIONS: The modified GnRH antagonist protocol using the Gn step-down approach and cessation of GnRH antagonist on the hCG day is effective in improving live birth rates (LBRs) per fresh eSET cycle.
BACKGROUND: Currently, there is no consensus on optimal GnRH antagonist regimens. Studies have shown that fresh GnRH antagonist cycles result in poorer pregnancy outcomes than the long GnRH agonist (GnRHa) protocol. Endometrial receptivity is a key factor that contributes to this phenomenon.
METHODS: An open label randomized controlled trial (RCT) was performed between November 2021 and August 2022. There were 546 patients allocated to either the modified GnRH antagonist or the conventional antagonist protocol at a 1:1 ratio.
METHODS: Both IVF and ICSI cycles were included, and the sperm samples used were either fresh or frozen from the partner, or from frozen donor ejaculates. The primary outcome was the LBRs per fresh SET cycle. Secondary outcomes included rates of implantation, clinical and ongoing pregnancy, miscarriage, and ovarian hyperstimulation syndrome (OHSS), as well as clinical outcomes of ovarian stimulation.
RESULTS: Baseline demographic features were not significantly different between the two ovarian stimulation groups. However, in the intention-to-treat (ITT) population, the LBRs in the modified antagonist group were significantly higher than in the conventional group (38.1% [104/273] vs. 27.5% [75/273], relative risk 1.39 [95% CI, 1.09-1.77], P = 0.008). Using a per-protocol (PP) analysis which included all the patients who received an embryo transfer, the LBRs in the modified antagonist group were also significantly higher than in the conventional group (48.6% [103/212] vs. 36.8% [74/201], relative risk 1.32 [95% CI, 1.05-1.66], P = 0.016). The modified antagonist group achieved significantly higher implantation rates, and clinical and ongoing pregnancy rates than the conventional group in both the ITT and PP analyses (P < 0.05). The two groups did not show significant differences between the number of oocytes retrieved or mature oocytes, two-pronuclear zygote (2PN) rates, the number of embryos obtained, blastocyst progression and good-quality embryo rates, early miscarriage rates, or OHSS incidence rates (P > 0.05).
CONCLUSIONS: A limitation of our study was that the subjects were not blinded to the treatment allocation in the RCT trial. Only women under 40 years of age who had a good prognosis were included in the analysis. Therefore, use of the modified antagonist protocol in older patients with a low ovarian reserve remains to be investigated. In addition, the sample size for Day 5 elective SET was small, so larger trials will be required to strengthen these findings.
CONCLUSIONS: The modified GnRH antagonist protocol using the Gn step-down approach and cessation of GnRH antagonist on hCG day improved the LBRs per fresh eSET cycle in normal responders.
BACKGROUND: This project was funded by grant 2022YFC2702503 from the National Key Research & Development Program of China and grant 2021140 from the Beijing Health Promotion Association. The authors declare no conflicts of interest.
BACKGROUND: The RCT was registered in the Chinese Clinical Trial Registry; Study Number: ChiCTR2100053453.
UNASSIGNED: 21 November 2021.
UNASSIGNED: 23 November 2021.

UNASSIGNED: The utilization of frozen embryo transfer not only enhances reproductive outcomes by elevating the likelihood of live birth and clinical pregnancy but also improves safety by mitigating the risks associated with ovarian hyperstimulation syndrome (OHSS) and multiple pregnancies. There has been an increasing debate in recent years regarding the advisability of making elective frozen embryo transfer the standard practice. Our study aims to determine the optimal choice between fresh and frozen embryo transfer, as well as whether the transfer should occur at the cleavage or blastocyst stage.
UNASSIGNED: In this retrospective cohort study conducted in Taiwan, data from the national assisted reproductive technology (ART) database spanning from January 1st, 2013, to December 31st, 2017, were analyzed. The study included 51,762 eligible female participants who underwent ART and embryo transfer. Pregnancy outcomes, maternal complications, and singleton neonatal outcomes were evaluated using the National Health Insurance Database from January 1st, 2013, to December 31st, 2018. Cases were categorized into groups based on whether they underwent fresh or frozen embryo transfers, with further subdivision into cleavage stage and blastocyst stage transfers. Exposure variables encompassed clinical pregnancy rate, live birth rate, OHSS, pregnancy-induced hypertension, gestational diabetes mellitus (DM), placenta previa, placental abruption, preterm premature rupture of membranes (PPROM), gestational age, newborn body weight, and route of delivery.
UNASSIGNED: Frozen blastocyst transfers showed higher rates of clinical pregnancy (CPR) and live births (LBR) compared to fresh blastocyst transfers. Conversely, frozen cleavage stage transfers demonstrated lower rates of clinical pregnancy and live birth compared to fresh cleavage stage transfers. Frozen embryo transfers were associated with reduced risks of OHSS but were linked to a higher risk of pregnancy-induced hypertension compared to fresh embryo transfers. Additionally, frozen embryo transfers were associated with a higher incidence of large for gestational age infants and a lower incidence of small for gestational age infants.
UNASSIGNED: The freeze-all strategy may not be suitable for universal application. When embryos can develop to the blastocyst stage, FET is a favorable choice, but embryos can only develop to the cleavage stage, fresh embryo transfer becomes a more reasonable option.

The number of surplus frozen human embryos in storage in the United Kingdom (UK) is at its highest level since records began in 1991 and the formation of the UK Human Fertilisation and Embryology Authority (HFEA). This study features a quantitative analysis of data from 1991 to 2019 provided by the HFEA as well as a commentary on observed trends within this data. We also discuss trends relating to the final destiny of surplus embryos. Data analysis show that at least 130,000 stored embryos have been discarded in the UK since 1991, while another 500,000 embryos are currently being stored in a frozen state, of which a significant proportion is likely to be discarded in the future. However, this creates a moral dilemma since UK legislation relating to human embryos is based on the 1984 Warnock Report which recognizes that they have a special moral status.

Objectives: In vitro fertilization (IVF) has the potential to give babies to millions more people globally, yet it continues to be underutilized. We established a globally applicable and locally adaptable IVF prognostics report and framework to support patient-provider counseling and enable validated, data-driven treatment decisions. This study investigates the IVF utilization rates associated with the usage of machine learning, center-specific (MLCS) prognostic reports (the Univfy® report) in provider-patient pre-treatment and IVF counseling. Methods: We used a retrospective cohort comprising 24,238 patients with new patient visits (NPV) from 2016 to 2022 across seven fertility centers in 17 locations in seven US states and Ontario, Canada. We tested the association of Univfy report usage and first intra-uterine insemination (IUI) and/or first IVF usage (a.k.a. conversion) within 180 days, 360 days, and \"Ever\" of NPV as primary outcomes. Results: Univfy report usage was associated with higher direct IVF conversion (without prior IUI), with odds ratios (OR) 3.13 (95% CI 2.83, 3.46), 2.89 (95% CI 2.63, 3.17), and 2.04 (95% CI 1.90, 2.20) and total IVF conversion (with or without prior IUI), OR 3.41 (95% CI 3.09, 3.75), 3.81 (95% CI 3.49, 4.16), and 2.78 (95% CI 2.59, 2.98) in 180-day, 360-day, and Ever analyses, respectively; p < 0.05. Among patients with Univfy report usage, after accounting for center as a factor, older age was a small yet independent predictor of IVF conversion. Conclusions: Usage of a patient-centric, MLCS-based prognostics report was associated with increased IVF conversion among new fertility patients. Further research to study factors influencing treatment decision making and real-world optimization of patient-centric workflows utilizing the MLCS reports is warranted.

BACKGROUND: Perfluorinated alkyl acids (PFAAs) are persistent organic pollutants affected by BMI and ethnicity, with contradictory reports of association with vitamin D deficiency.
METHODS: Twenty-nine Caucasian women with non-obese polycystic ovary syndrome (PCOS) and age- and BMI-matched Caucasian control women (n = 30) were recruited. Paired serum samples were analyzed for PFAAs (n = 13) using high-performance liquid chromatography-tandem mass spectrometry. Tandem mass spectrometry determined levels of 25(OH)D3 and the active 1,25(OH)2D3.
RESULTS: Women with and without PCOS did not differ in age, weight, insulin resistance, or systemic inflammation (C-reactive protein did not differ), but the free androgen index was increased. Four PFAAs were detected in all serum samples: perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS). Serum PFOS was higher in PCOS versus controls (geometric mean [GM] 3.9 vs. 3.1 ng/mL, p < 0.05). Linear regression modeling showed that elevated PFHxS had higher odds of a lower 25(OH)D3 (OR: 2.919, 95% CI 0.82-5.75, p = 0.04). Vitamin D did not differ between cohorts and did not correlate with any PFAAs, either alone or when the groups were combined. When vitamin D was stratified into sufficiency (>20 ng/mL) and deficiency (<20 ng/mL), no correlation with any PFAAs was seen.
CONCLUSIONS: While the analyses and findings here are exploratory in light of relatively small recruitment numbers, when age, BMI, and insulin resistance are accounted for, the PFAAs do not appear to be related to 25(OH)D3 or the active 1,25(OH)2D3 in this Caucasian population, nor do they appear to be associated with vitamin D deficiency, suggesting that future studies must account for these factors in the analysis.

The sperm-specific phospholipase C zeta (PLCζ) protein is widely considered as the predominant physiological stimulus for initiating the Ca2+ release responsible for oocyte activation during mammalian fertilization. The increasing number of genetic and clinical reports that directly link PLCζ defects and/or deficiencies with oocyte activation failure (OAF) necessitates the use of a powerful therapeutic intervention to overcome such cases of male factor infertility. Currently, in vitro fertilization (IVF) clinics treat OAF cases after intracytoplasmic sperm injection (ICSI) with Ca2+ ionophores. Despite their successful use, such chemical agents are unable to trigger the physiological pattern of Ca2+ oscillations. Moreover, the safety of these ionophores is not yet fully established. We have previously demonstrated that recombinant PLCζ protein can be successfully used to rescue failed oocyte activation, resulting in efficient blastocyst formation. Herein, we produced a maltose binding protein (MBP)-tagged recombinant human PLCζ protein capable of inducing Ca2+ oscillations in mouse oocytes similar to those observed at fertilization. Circular dichroism (CD) experiments revealed a stable, well-folded protein with a high helical content. Moreover, the recombinant protein could retain its enzymatic properties for at least up to 90 days after storage at -80 °C. Finally, a chick embryo model was employed and revealed that exposure of fertilized chicken eggs to MBP-PLCζ did not alter the embryonic viability when compared to the control, giving a first indication of its safety. Our data support the potential use of the MBP-PLCζ recombinant protein as an effective therapeutic tool but further studies are required prior to its use in a clinical setting.

BACKGROUND: In vitro fertilization is the most used assisted reproductive technology in the United States that is increasing in efficiency and in demand. Certain states have mandated coverage that enable individuals with low income to undergo in vitro fertilization treatment.
OBJECTIVE: This study aimed to evaluate if socioeconomic status has an impact on the perinatal outcomes in in vitro fertilization pregnancies. We hypothesized that with greater coverage there may be an alleviation of the financial burden of in vitro fertilization that can facilitate the application of evidence-based practices.
METHODS: This was a retrospective, population-based, observational study that was conducted in accordance with the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample database over the 6-year period from 2008 to 2014 during which period 10,000 in vitro fertilization deliveries were examined. Maternal outcomes of interest included preterm prelabor rupture of membranes, preterm birth (ie, before 37 weeks of gestation), placental abruption, cesarean delivery, operative vaginal delivery, spontaneous vaginal delivery, maternal infection, chorioamnionitis, hysterectomy, and postpartum hemorrhage. Neonatal outcomes included small for gestational age neonates, defined as birthweight <10th percentile, intrauterine fetal death, and congenital anomalies.
RESULTS: Our study found that the socioeconomic status did not have a statistically relevant effect on the perinatal outcomes among women who underwent in vitro fertilization to conceive after adjusting for the potential confounding effects of maternal demographic, preexisting clinical characteristics, and comorbidities.
CONCLUSIONS: The literature suggests that in states with mandated in vitro fertilization coverage, there are better perinatal outcomes because, in part, of the increased use of best in vitro fertilization practices, such as single-embryo transfers. Moreover, the quality of medical care in states with coverage is in the highest quartile in the country. Therefore, our findings of equivalent perinatal outcomes in in vitro fertilization care irrespective of socioeconomic status possibly suggests that a lack of access to quality medical care may be a factor in the health disparities usually seen among individuals with lower socioeconomic status.

OBJECTIVE: Investigate patient preferences in embryo selection for transfer regarding quality versus sex in IVF/ICSI cycles with PGT-A and assess associated clinical implications.
METHODS: Retrospective cohort study at a university fertility practice from January 2012 to December 2021. Included were patients undergoing single frozen euploid transfers with at least one embryo of each sex available. Primary outcomes were preference for embryo selection (quality vs. sex) and sex preference (male vs. female). Trends over 10 years were evaluated and clinical outcomes, including clinical pregnancy rate (CPR), sustained implantation rate (SIR), and live birth rate (LBR), were compared.
RESULTS: A total of 5,145 embryo transfer cycles were included; 54.5% chose the best-quality embryo, while 45.5% selected based on sex. Among those choosing based on sex, 56.5% chose male embryos and 43.5% chose female. Preference for quality remained consistent over the decade (p = 0.30), while male embryos were consistently favored (p = 0.64). Best-quality embryos had higher grades (p < 0.001). Clinical outcomes were similar between groups (CPR: 74.4% vs. 71.9%, p = 0.05; SIR: 64.9% vs. 63.4%, p = 0.26; LBR: 58.8% vs. 56.7%, p = 0.13), and between male and female embryo selections.
CONCLUSIONS: Sex selection remains common, with 45.5% selecting embryos based on sex, predominantly favoring males. This trend persisted over 10 years, with comparable clinical outcomes regardless of selection criteria.

OBJECTIVE: This study estimates the need of IVF/ICSI in Australia as compared to its actual uptake.
METHODS: We created a model estimating for the annual demand for IVF/ICSI in a hypothetical infertile population, using demographic data from medical literature and Australian government databases. For each category of infertility (tubal, severe male, endometriosis, anovulation and unexplained), our estimated need for IVF/ICSI was compared to the actual IVF/ICSI uptake (ANZARD 2019). The model consisted of three categories depending on couples\' cause of infertility, i.e. couples with absolute indications for IVF/ICSI (couples with severe male factor infertility and tubal obstruction); couples with anovulatory infertility (couples with ovulation disorders) and couples with ovulatory infertility (couples suffering from unexplained infertility and endometriosis). The model was applied to each of these categories to determine the number of couples that would require IVF/ICSI treatment after failing to conceive naturally or after following alternative treatment plans. The main outcomes of this study were the estimate of IVF/ICSI cycles and the difference between the estimate and the reported number of IVF/ICSI cycles (2019 ANZARD report).
RESULTS: We estimated that approximately 35,300 couples required IVF/ICSI treatment in Australia in 2019, while in 2019 according to ANZARD, 46,000 couples underwent IVF/ICSI. A higher uptake of IVF/ICSI cycles than expected was specifically reported in couples with unexplained infertility, ovulation disorders and endometriosis, while for tubal and severe male infertility uptake seemed adequate.
CONCLUSIONS: In Australia, there seems to be overservicing of IVF/ICSI, specifically for unexplained, ovulatory and endometriosis-related infertility.