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: Hydrosalpinx impairs the success of in vitro fertilization (IVF) embryo transfer. Various surgical approaches, such as fluid aspiration or isolation of the affected fallopian tubes, have been used to enhance the outcome. This study was conducted to evaluate and compare the efficacy of laparoscopic tubal disconnection (LTD) and hydroscopic tubal electrocoagulation (HTE) for hydrosalpinx before IVF.
UNASSIGNED: After obtaining ethical committee approval, we assessed 112 women who were subfertile due to hydrosalpinx to check their adherence to our selection criteria. Eligible patients were allocated into two groups (LTD vs. HTE). Both groups underwent extensive assessment before the operative procedure. IVF and subsequent embryo transfers were performed in both groups. Live birth and pregnancy rates were evaluated.
UNASSIGNED: Patients who underwent LTD prior to IVF embryo transfer had significantly higher live birth (41%), clinical pregnancy (57%), and chemical pregnancy (61%) rates in the LTD group than in the HTE group (12%, 35%, 41%, respectively). However, we could not find a significant difference between the two groups regarding the miscarriage (17% vs. 28%, p=0.33) and multiple pregnancy (14% vs. 12%, p=0.79) rates. No major complications with HTE were observed, except for a case of uterine perforation, whereas two cases of surgical complications occurred in the LTD group. Additionally, we found a significantly shorter operative time and hospital stay (0.5±0.7 days, p=0.012) in the HTE group.
UNASSIGNED: LTD may be a more effective approach compared with hysteroscopic tubal electrocoagulation for improving birth and pregnancy rates in patients with IVF and hydrosalpinx.

OBJECTIVE: Is the mode of conception (natural, subfertility and non-IVF, and IVF) associated with the risk of Type 1 diabetes mellitus among offspring?
CONCLUSIONS: The risk of Type 1 diabetes in offspring does not differ among natural, subfertility and non-IVF, and IVF conceptions.
BACKGROUND: Evidence has shown that children born through IVF have an increased risk of impaired metabolic function.
METHODS: A population-based, nested case-control study was carried out, including 769 children with and 3110 children without Type 1 diabetes mellitus within the prospective cohort of 2 228 073 eligible parent-child triads between 1 January 2004 and 31 December 2017.
METHODS: Using registry data from Taiwan, the mode of conception was divided into three categories: natural conception, subfertility, and non-IVF (indicating infertility diagnosis but no IVF-facilitated conception), and IVF conception. The diagnosis of Type 1 diabetes mellitus was determined according to the International Classification of Diseases, 9th or 10th Revision, Clinical Modification. Each case was matched to four controls randomly selected after matching for child age and sex, residential township, and calendar date of Type 1 diabetes mellitus occurrence.
RESULTS: Based on 14.3 million person-years of follow-up (median, 10 years), the incidence rates of Type 1 diabetes were 5.33, 5.61, and 4.74 per 100 000 person-years for natural, subfertility and non-IVF, and IVF conceptions, respectively. Compared with natural conception, no significant differences in the risk of Type 1 diabetes were observed for subfertility and non-IVF conception (adjusted odds ratio, 1.04 [95% CI, 0.85-1.27]) and IVF conception (adjusted odds ratio, 1.00 [95% CI, 0.50-2.03]). In addition, there were no significant differences in the risk of Type 1 diabetes according to infertility source (male/female/both) and embryo type (fresh/frozen).
CONCLUSIONS: Although the population-level data from Taiwanese registries was used, a limited number of exposed cases was included. We showed risk of Type 1 diabetes was not associated with infertility source or embryo type; however, caution with interpretation is required owing to the limited number of exposed events after the stratification. The exclusion criterion regarding parents\' history of diabetes mellitus was only applicable after 1997, and this might have caused residual confounding.
CONCLUSIONS: It has been reported that children born to parents who conceived through IVF had worse metabolic profiles than those who conceived naturally. Considering the findings of the present and previous studies, poor metabolic profiles may not be sufficient to develop Type 1 diabetes mellitus during childhood.
BACKGROUND: This study was supported by grants from Shin Kong Wu Ho-Su Memorial Hospital (No. 109GB006-1). The funders had no role in considering the study design or in the collection, analysis, interpretation of data, writing of the report, or decision to submit the article for publication. The authors have no competing interests to disclose.
BACKGROUND: N/A.

OBJECTIVE: Does artificial shrinkage before fresh blastocyst transfer improve clinical pregnancy rates in IVF?
METHODS: In this monocentric prospective, randomized, double-blind, controlled pilot study, 150 couples undergoing fresh single-blastocyst transfer were randomized between 20 May 2018 and 22 February 2022. In the artificial shrinkage group (AS group), a single laser pulse was directed to the cellular junction of the trophectoderm on the opposite side of the inner cell mass in each blastocyst. IVF outcomes were clinical pregnancy, multiple pregnancy and live birth rates. Cell-free DNA (cfDNA) concentration was also measured by quantitative real-time PCR in the blastocyst culture medium.
RESULTS: In total, 142 couples underwent fresh single-blastocyst transfer: control group, no artificial shrinkage, n = 47; and AS group, artificial shrinkage, n = 95; An intention-to-treat (ITT) analysis was employed. After a reassessment and the exclusion of patients with major protocol deviations, 139 couples underwent fresh single-blastocyst transfer under optimal conditions: control group, n = 47; and AS group, n = 92; a per-protocol analysis was used here. The clinical and laboratory characteristics were not significantly different between the groups. The clinical pregnancy rate was similar in the control and AS groups (ITT: 48.9% versus 49.5%, P = 0.97; per protocol: 48.94% versus 51.1%, P = 0.89). The multiple pregnancy rate and the live birth rate were also similar between the groups. No significant differences in gestational age, birthweight or proportion of male/female newborns were observed. The concentration of cfDNA in the blastocyst culture medium was not associated with IVF outcome.
CONCLUSIONS: Large-scale randomized controlled trials are required to confirm these preliminary results.

OBJECTIVE: What are the metabolic characteristics of follicular fluid in patients with ovarian endometriosis undergoing IVF?
METHODS: This was an exploratory cohort study on endometriosis. In total, 19 infertile patients with ovarian endometriosis diagnosed by laparoscopy, and 23 controls matched in terms of age and body mass index (women with infertility due to male or tubal factors) were enrolled in this study. All patients underwent IVF treatment with a gonadotrophin-releasing hormone antagonist protocol, and follicular fluid was collected at oocyte retrieval. The metabolomics of follicular fluid samples was analysed using an ultra-high-performance liquid chromatography Orbitrap Exploris mass spectrometer (UHPLC-OE-MS). The best combination of biomarkers was selected by performing stepwise logistic regression analysis with backward elimination.
RESULTS: Fifteen metabolites were identified as biomarkers associated with endometriosis. A final model containing 8-hydroxy-2-deoxyguanosine, biotin, n-acetyl-L-methionine and n-methylnicotinamide was constructed. Receiver operating characteristic analysis confirmed the value of these parameters in diagnosing endometriosis, with sensitivity of 94.7% and specificity of 95.7%. Enrichment analysis via the Kyoto Encyclopedia of Genes and Genome showed that 15 metabolites were enriched in eight metabolic pathways.
CONCLUSIONS: Metabolomics based on UHPLC-OE-MS effectively characterized the metabolomics analysis of follicular fluid in patients with ovarian endometriosis. These findings may provide a new basis for better understanding of how diseases progress, and for the discovery of new biomarkers.

OBJECTIVE: What differences exist in the phenotypes of pre-eclampsia, perinatal outcomes and neonatal echocardiography between pregnancies conceived naturally and through IVF?
METHODS: Six hundred and ten women diagnosed with pre-eclampsia between January 2002 and December 2022 were included in this study. This research was conducted within the IVF and Maternal-Fetal Medicine Department of Kaohsiung Chang Gung Memorial Hospital, Taiwan. Participants were divided into two groups: those who achieved pregnancy through IVF, and those who conceived naturally. The phenotypes of pre-eclampsia and perinatal outcomes were assessed using a propensity-matched sample (n = 218), along with neonatal echocardiography.
RESULTS: After conducting propensity score matching, the natural conception group had a higher prevalence of early-onset pre-eclampsia (53.9% versus 37.7%, P = 0.04) and exhibited more severe features of pre-eclampsia (89.1% versus 69.8%, P = 0.01) compared with the IVF group. Regarding perinatal outcomes, neonates in the IVF group had higher placental weights compared with the natural conception group (580 versus 480 g, P = 0.031). The prevalence of abnormal findings on neonatal echocardiography was similar between the groups. Multivariate analysis showed that greater gestational age at delivery reduced the likelihood of abnormal findings on echocardiography [adjusted risk ratio (aRR) 0.950, P = 0.001], while pregestational diabetes mellitus increased the likelihood of abnormal findings (aRR 1.451, P = 0.044). Septal defects were the most common type of defect, occurring in 16.1% of infants.
CONCLUSIONS: The impact of IVF conception on the severity of pre-eclampsia is not as expected. Neonatal echocardiography revealed a higher prevalence of abnormalities in offspring of women with pre-eclampsia compared with the general population. However, these issues were not linked to the method of conception, suggesting the existence of undisclosed factors that could influence the clinical features and perinatal outcomes of pre-eclampsia.

OBJECTIVE: Comparison of naturally conceived pregnancy with IVFET pregnancy for feto-maternal outcome and morphology and histopathology of placenta & umbilical cord.
METHODS: 100 pregnant women were divided into 2 subsets of spontaneous pregnancy group (n = 50) and the IVFET pregnancy group (n = 50).The two groups were compared for Maternal age, parity, maternal weight gain, prepregnancy maternal BMI, gestational age, birth weight of baby, placental weight, placenta and umbilical cord cross sections, insertion site of the umbilical cord, and length of the umbilical cord.
METHODS: Patients registered at ANC OPD/ART centre of our institute and subsequently reporting to maternity ward/ labor room for delivery at our centre.
METHODS: The pregnancies conceived after ART outside our institute, multifetal pregnancies. Study duration: 01 year Results: Our study revealed that spontaneous pregnancy group had less antenatal co-morbidities with more number of term vaginal deliveries and less intrapartum and neonatal complications compared to IVFET pregnancy women (p < 0.05).
CONCLUSIONS: Assisted reproductive technologies have an impact on placental growth and function in pregnancy. The occurrence of placental abnormalities were the most significant and pertinent finding in the IVF-ET placentas. On histopathological examination maternal vascular malperfusion and concomitant anomalies of the umbilical cord were most noticeable findings.

OBJECTIVE: Is SARS-CoV-2 infection in IVF-conceived early pregnancy associated with a higher risk of miscarriage?
CONCLUSIONS: Infection with SARS-CoV-2 during early pregnancy in women conceiving by IVF may not be associated with an increased rate of miscarriage.
BACKGROUND: In naturally conceived pregnancies, most findings have shown that SARS-CoV-2 infection does not increase the risk of miscarriage, while some studies have shown that SARS-CoV-2 infection is associated with a higher risk of miscarriage.
UNASSIGNED: A matched retrospective cohort study was conducted in a tertiary hospital-based reproductive medicine center. The infection group included women who contracted coronavirus disease 2019 (COVID-19) before 20 weeks gestation from 6 December 2022 to 10 January 2023. Each infected woman was matched with three historical control subjects from 1 January 2018 to 31 May 2022.
METHODS: The infection group was matched with historical control subjects based on female age (±1 year), number of gestational sacs, number of previous miscarriages, BMI (±2 kg/cm2), main causes of infertility, gestational week, and fresh versus frozen embryo transfer.
RESULTS: A total of 150 pregnant women infected with COVID-19 before 20 weeks of gestation were included in the infection group, which was matched at a 3:1 ratio with 450 historically pregnant controls. There were no significant differences in age, BMI, and endometrial thickness between the two groups. The overall incidence of miscarriage was not significantly different between the infection group and the control group (4.7% versus 5.8%, P = 0.68). When the infection group was stratified into three subgroups based on the gestational age at the onset of infection (0-7 + 6, 8-11 + 6, and 12-19 + 6 weeks), no significant differences were observed in the incidence of miscarriage between the infection group and the matched control group in any of the subgroups (9.8% versus 13.8%, P = 0.60; 5.4% versus 4.5%, P = 1.00; and 1.4% versus 1.9%, P = 1.00, respectively).
CONCLUSIONS: The major limitation of this study is the relatively small sample size; therefore, caution is suggested when drawing any definitive conclusions. Nonetheless, our study is the largest sample study of the influence of COVID-19 infection on the miscarriage rate in early pregnancy after IVF.
CONCLUSIONS: Our findings may provide important insights for reproductive physicians and obstetricians during preconception and early pregnancy counseling.
BACKGROUND: This study was supported by the Natural Science Foundation of Guangdong Province (No. 2023A1515010250). The authors report no conflicts of interest.
BACKGROUND: N/A.

UNASSIGNED: Low-dose aspirin is one of the widely used adjuvants in assisted reproductive technologies with the hope of improving the live birth rate. However, the studies regarding its effects are conflicting. The study aimed to investigate the association between aspirin administration and live birth following frozen-thawed embryo transfer (FET) in patients with different body mass index (BMI).
UNASSIGNED: A retrospective cohort study was performed on 11,993 patients receiving FET treatments. 644 of which received a low-dose aspirin (100 mg/day) during endometrial preparation until 10 weeks after transfer. Propensity score matching was performed to avoid selection biases and potential confounders.
UNASSIGNED: The clinical pregnancy rate and live birth rate were similar before matching (54.4% versus 55.4%, RR: 1.02, 95%CI: 0.95-1.09, and 46.3 versus 47.8, RR: 1.03, 95%CI: 0.95-1.12 respectively). A weak association in favor of aspirin administration was found in the matched cohort (49.5% versus 55.4%, RR: 1.12, 95%CI: 1.01-1.24, and 41.9% versus 47.8%, RR: 1.14, 95%CI: 1.01-1.29 respectively). However, when stratified the patients with WHO BMI criteria, a significant increase in live birth rate associated with aspirin treatment was found only in patients with low BMI (<18.5 kg/m2) in either unmatched (46.4% versus 59.8%, RR:1.29, 95%CI:1.07-1.55) or matched cohort (44% versus 59.8%, RR: 1.36, 95%CI: 1.01-1.83) but not in patients with higher BMI categories. With the interaction analysis, less association between aspirin and live birth appeared in patients with normal BMI (Ratio of OR:0.49, 95%CI: 0.29-0.81) and high BMI (Ratio of OR:0.57, 95%CI: 0.27-1.2) compared with patients with low BMI.
UNASSIGNED: BMI may be considered when evaluating aspirin\'s effect in FET cycles.

UNASSIGNED: Polycystic ovarian syndrome (PCOS) is one of the significant causes of infertility. Impaired glucose metabolism and insulin resistance add chiefly to the pathogenesis of PCOS. This study aimed to evaluate the efficacy of metformin and pioglitazone (insulin sensitizers) on the quality of the ovum and pregnancy rate in the IVF cycle.
UNASSIGNED: In this randomized clinical trial study, 172 infertile women with PCO were enrolled and randomly assigned to receive either 15 mg pioglitazone (case group) or 1000 mg metformin (control group) twice a day for 6 weeks before IVF, and the pregnancy rate was compared across the groups. The number of ovum and embryos were also accessed and compared between the two groups.
UNASSIGNED: In the study, 172 patients participated. The mean age in the control and case groups was 32.09±3.9 years and 32.12±3.9 years, respectively, with no significant age difference. In both groups, the mean number of IVF eggs retrieved was 11.76±3.7 (control) and 11.86±3.7 (case), and the number of embryos formed was 7.43±2.8 (control) and 7.87±3.5 (case), with no significant disparities (P<0.05). Regarding positive pregnancies, 28 out of 86 (32.6%) occurred in the control group, while 42 out of 86 (48.8%) happened in the case group, demonstrating a significant difference (P=0.03).
UNASSIGNED: According to the results obtained in this study, it may be concluded that pioglitazone is superior to metformin in IVF cycles in PCOS-associated infertile women leading to a higher pregnancy rate.