Human reproduction最新文献

{"title":"L26/P-861 Twin pregnancies conceived by assisted reproductive treatments and the risk of long-term offspring pediatric neurological morbidity","authors":"N. Leybovitz Haleluya, N. Steiner, T. Wainstock, E. Sheiner","doi":"10.1093/humrep/deag083.1186","DOIUrl":"https://doi.org/10.1093/humrep/deag083.1186","url":null,"abstract":"Study question We studied the association between ART leading to twin pregnancy and long- term neurological morbidity of offspring. Summary answer Twins conceived by IVF are at increased risk for long-term pediatric neurological morbidity. What is known already Evidence is conflicting whether twins conceived by assisted reproductive treatment (ART( have higher rate of adverse outcomes than twins conceived spontaneously. Specifically, scarce data exist regarding the long-term neurological implications. Study design, size, duration A retrospective cohort study including twins born between the years 1991-2021 at a tertiary medical center was conducted. Participants/materials, setting, methods Total and subtypes of neurological morbidity among twins born following in vitro fertilization (IVF) versus ovulation induction (OI) and no ART were compared. A Kaplan-Meier survival curve was used to compare cumulative neurological morbidity incidence, and a Cox proportional hazards models were constructed to adjust for confounders. Main results and the role of chance The study population included 7790 twins; 1380 (17.7%) were conceived by IVF, 696 (8.9%) by OI and 5741 (73.7%) were conceived spontaneously. An independent significant association was found between IVF and preterm delivery<37 weeks and cesarean delivery (CD). Higher rates of total neurological morbidity were noted in ART groups (30.1% in IVF, 34.4% in OI and 20.5% in spontaneous group, p < 0.001). Cumulative rates of long-term total neurological morbidity were significantly higher among offspring in ART groups. Using a Cox proportional hazards model, controlling for potential confounders, the association between IVF and the risk for neurological pediatric morbidity remained significant (Adjusted HR = 1.16, 95% CI 1.02-1.33, p=0.029). However, no independent association was found between OI and neurological morbidity. Limitations, reasons for caution The main advantage relates to the large cohort size, loss to follow up and selection bias minimal. In addition, in Israel, fertility treatments are fully covered by Health Insurance Law, making our cohort representative of the general population and thus allowing stronger generalizability.The main limitation lies within its retrospective design. Wider implications of the findings We demonstrates an increased risk for preterm delivery<37 weeks and CD in the short-term, as well as higher risk of long-term pediatric neurological morbidity among twins conceived by IVF. Future research is needed to differentiate the impact of IVF alone regardless of parental confounding factors. Trial registration number No","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"225 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/O-279 Assessment of uterine peristaltic patterns of women with adenomyosis by means of intracavitary electrohysterography: preliminary results","authors":"P. Alama, J. Llácer, A. Diaz, J.M. Mira-Tomas, G. Castillón, S. Caballero, J. Garcia-Casado, J. Alberola-Rubio, J. Imaz-Higuera","doi":"10.1093/humrep/deag083.277","DOIUrl":"https://doi.org/10.1093/humrep/deag083.277","url":null,"abstract":"Study question Do uterine electrophysiological contractile parameters across the menstrual cycle differ between women with adenomyosis and healthy controls? Summary answer Women with adenomyosis show altered cycle-dependent uterine electrophysiological patterns, with higher contraction frequency and contraction time, and reduced amplitude across all menstrual phases. What is known already Adenomyosis is a pathological condition where endometrial invasion into the myometrium disrupts the junctional zone, causing altered uterine peristalsis. These disturbances can severely impair directed sperm transport and may negatively affect embryo implantation or preservation Despite the recognised contribution of such mechanical dysfunctions to subfertility and increased miscarriage rates, uterine peristalsis in women with this condition has not been evaluated in detail and objectively due to the limitations of image-based monitoring techniques. IC-EHG is an innovative technique which has been demonstrated to facilitate a thorough and objective evaluation of uterine peristalsis in healthy women. (Alberola-Rubio, 2025; Imaz-Higuera, 2025). Study design, size, duration This prospective cohort study included 40 healthy women and 20 women diagnosed with adenomyosis who underwent IC-EHG recordings during three menstrual phases: mid-follicular (MF), early luteal (EL), and late luteal (LL). The study was conducted as a prospective multicentre cohort across five fertility clinics in Spain (IVI Madrid, IVI Valencia, IVI Barcelona, IVI Bilbao, and GineFiv Madrid). Participants/materials, setting, methods Participants underwent 30-minute IC-EHG recordings using a multipolar catheter positioned under ultrasound guidance. Only the signal from the uterine fundus was studied. Uterine contractions were identified automatically and three electrophysiological parameters were computed: contraction frequency, amplitude, and time percentage (Alberola-Rubio et al., 2025). Between-group comparisons (adenomyosis vs healthy) were performed using the Wilcoxon rank-sum test for each phase. In order to perform between-phase comparisons, the Wilcoxon signed-rank test was utilised for each group.. Main results and the role of chance Women with adenomyosis exhibited distinct uterine electrophysiological patterns compared with healthy controls. Between-group analyses revealed higher contraction frequency in adenomyosis, reaching statistical significance during the EL phase (p = 0.022). Contraction amplitude was consistently lower in adenomyosis across the menstrual cycle, reaching statistical significance in the MF and EL phases (p = 0.019 and p = 0.018, respectively). Furthermore, contraction time percentage tended to be higher throughout the cycle in adenomyosis group, with significant differences observed in LL phase (p = 0.020). Cycle-related trends were similar for healthy and adenomyosis groups in the frequency of contractions s. However, statistically significant differences between","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"25 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/P-705 Serum omega-3 and omega-6 polyunsaturated fatty acids and ovarian stimulation outcomes in assisted reproductive technologies: A prospective cohort study","authors":"X. Shen, X. Zhang, Y. Allan, A. Salas-Huetos, Y. Wu, I. Souter, D. Zhang, Q. Sun, L. Mínguez-Alarcón, J. Chavarro","doi":"10.1093/humrep/deag083.1034","DOIUrl":"https://doi.org/10.1093/humrep/deag083.1034","url":null,"abstract":"Study question Are serum polyunsaturated fatty acids (PUFAs) levels, a biomarker of intake, associated with ovarian stimulation outcomes in assisted reproductive technology (ART) treatment cycles? Summary answer: Summary answer Serum ω-6 PUFAs levels were positively associated with peak estradiol levels, and this association depended on serum ω-3 PUFAs levels. What is known already ω-3 and ω-6 PUFAs are considered essential fatty acids as they cannot be synthesized de novo by humans and must be obtained from diet. PUFAs are involved in important biological processes in the female reproductive system, acting as energy substrates during oocyte maturation and early embryo development, and serving as precursors of prostaglandin and steroid hormones. Epidemiological evidence suggests higher intakes of ω-3 PUFAs and their food sources are associated with favorable fertility-related outcomes, including lower risk of anovulation and higher live birth rates in ART. However, literature on their relationship with ovarian stimulation outcomes during infertility treatment remains limited. Study design, size, duration We analyzed ovarian stimulation outcomes of 456 fresh cycles from 353 women aged 18 to 45 years old, who participated in the Environment and Reproductive Health (EARTH) Study, a prospective cohort study that enrolled couples seeking infertility treatment at the Massachusetts General Hospital Fertility Center (Boston, MA, USA) (2004-2019). Examined exposures were serum fatty acids and fatty acid ratios. Outcomes were peak estradiol levels, total and metaphase II (MII) oocytes counts, and fertilization rate. Participants/materials, setting, methods Fatty acid levels were quantified by capillary gas chromatography in non-fasting blood samples collected during or shortly before their first in-study ART cycle. Generalized estimating equations (GEE) were used to account for repeated treatment cycles, with adjustments for age, body mass index, smoking status, education level and physical activity hours. When testing the associations of ω-3:ω-6 ratios, the models were additionally adjusted for both of the ω-3 and ω-6 PUFAs. Main results and the role of chance The participants had a median age of 35 years and BMI of 23.1 kg/m2. Most participants were white, highly educated, and had never smoked. Participants had a median (interquartile range, IQR) serum total ω3 and ω6-PUFAs of 4.31 (3.63, 5.87) % and 39.54 (36.70, 42.45) % of total fatty acids, respectively. Serum ω3-PUFAs were not associated with any outcomes examined. Instead, serum linoleic acid (LA) and total ω6-PUFAs exhibited significant positive associations with peak estradiol, but not with oocyte counts or fertilization rate. An IQR increase in serum LA and total ω6-PUFAs was associated with an increase in peak estradiol of 105.35 (0.90, 209.81) and 134.92 (37.92, 231.92) pmol/L, respectively. The ω6:ω3-PUFA and LA: a-linoleic acid (ALA) ratios were significantly related to peak estradiol and to","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"37 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/P-725 Follicular flushing does not increase oocyte yield compared with single aspiration in patients classified as poseidon groups 3 and 4: a randomized intra-patient controlled tria","authors":"P. Cirillo, A. Fuentes, B. Alcaraz, J.A. Ortiz, J.C. Castillo, A. Bernabeu","doi":"10.1093/humrep/deag083.1052","DOIUrl":"https://doi.org/10.1093/humrep/deag083.1052","url":null,"abstract":"Study question Does follicular flushing increase the number of cumulus–oocyte complexes (COCs) retrieved compared to single aspiration in patients classified as POSEIDON groups 3 and 4? Summary answer Follicular flushing does not increase the number of COCs retrieved compared to single aspiration in poor responder women. What is known already The number of cumulus–oocyte complexes (COCs) retrieved during oocyte pickup is a key determinant of IVF success. Follicular flushing has been proposed to increase oocyte recovery. Randomized studies show no oocyte yield benefit in normo-responders, while results in low responders are heterogeneous. Furthermore, most previous trials randomized patients to single aspiration or follicular flushing, potentially introducing heterogeneity between groups. A randomized trial minimized this bias by allocating each ovary to a different technique and reported a number of retrieved oocytes. However, patients in that study were not classified by low ovarian response criteria, which may identify those who could benefit. Study design, size, duration A prospective, randomized, controlled trial including 58 low responder patients (POSEIDON groups 3 and 4) was conducted between November 2025 and January 2026. Participants/materials, setting, methods After inclusion, ovarian stimulation followed an antagonist protocol. At oocyte retrieval, one ovary per patient was randomized to single aspiration (control) and the contralateral ovary to follicular flushing (study). Three operators performed all procedures. Follicles were aspirated with a 17G needle (Cook®) at 190 mmHg. In the flushing group, if no COC was obtained initially, flushing was performed up to three times using an technique. The embryologist reported COC recovery; time was measured per ovary. Main results and the role of chance A total of 58 women were included. Median age was 38 years (34–41), BMI 22.4 kg/m² (21.0–24.8), AMH 0.65 ng/mL (0.30–1.08), and antral follicle count 5 (4–8). The number of COCs retrieved was similar between flushing and control groups (1.58 ± 0.90 vs. 1.72 ± 1.19, p = 0.59). The oocyte retrieval rate at first aspiration was significantly higher in the control group compared to the flushing group (93.1% ± 25.7% vs. 15% ± 20.1%, p = <0.001). The overall oocyte retrieval rate was higher in the control group (93.1% ± 25.7% vs. 70.1% ± 41.7%, p = 0.04). When comparing the three flushing attempts, the oocyte recovery rate showed a progressive increase (11.5% ± 24 vs. 14.6% ± 27.4 vs 29.2% ± 25.7), with the highest rate observed at the third flushing, although this difference did not reach statistical significance. The duration of the intervention was significantly longer in the flushing group (223.3 sec ± 105.1 vs. 58.3 sec ± 32.7, p = <0.001). Limitations, reasons for caution The study was powered and designed to evaluate the true effect of follicular flushing on the number of COCs retrieved. However, it was not designed to assess i","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"226 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/P-394 Alleviating cryopreservation-induced damage with a mitochondria-targeted therapy to improve ovarian tissue survival and transplantation outcomes","authors":"J. Yang, H. Li, P. Zhao, K. Ma, Y. Li, R. Hua, Y. Huang, J.W.K. Ho, Y. Wang, W.S.B. Yeung, K. Liu, T. Wang","doi":"10.1093/humrep/deag083.728","DOIUrl":"https://doi.org/10.1093/humrep/deag083.728","url":null,"abstract":"Study question To investigate the key injuries during ovarian cryopreservation, and assess if M1 (mitochondria targeted compound) can mitigate cryoinjury and improve follicular survival after transplantation. Summary answer Mitochondrial dysfunction is a major cause of ovarian cryoinjury. M1 may enhance mitochondrial function, stromal integrity and cellular proliferation, thereby improving follicular survival after transplantation. What is known already Ovarian tissue cryopreservation and transplantation (OTCTP) offers a promising fertility preservation technique for prepubescent patients or those requiring urgent oncological treatment. However, the cryopreservation process causes cryoinjury through multiple mechanisms, including oxidative stress and cold stress, and eventually results in significant follicular loss after transplantation. Various strategies have been explored to mitigate cryopreservation-induced injury. M1, a sulfur-containing histidine derivative, acts as a natural mitochondrial-targeted product with antioxidant and anti-inflammatory properties. It can be transported into mitochondria to reduce ROS production. However, further investigation is needed to demonstrate the role of M1 during OTCTP. Study design, size, duration High-resolution spatial transcriptomics (Stereo-Seq) was used in 3 samples of human ovarian tissue (obtained from patients undergoing gynecological surgery, with informed consent and ethical approval), comparing fresh and slow-freezing samples. Ovarian tissue from 3-week-old female C57 mice was used. After in vitro culture for 2 days, mitochondrial function, stromal integrity and cellular proliferation were assessed in each group (M1 or control, n = 3). In vivo, the follicle survival was evaluated one week after transplantation. Participants/materials, setting, methods Stereo-Seq was employed to profile the molecular impacts of slow-freezing on human ovarian tissue. In mouse models, ovarian tissue from 3-week-old female C57 mice was slow-frozen with either 50 μM M1 or control added to cryoprotectant, thawing, and culture media. In vitro, tissues were analyzed for mitochondrial function (COX8A), stromal integrity (ACTA2) and proliferation (PCNA) with immunofluorescence (IF). In vivo, tissues were transplanted under the renal capsule and collected one week later for follicular analysis. Main results and the role of chance Spatial transcriptomics revealed significant downregulation of mitochondrial respiratory chain complex assembly genes (NDUFB4, NDUFS4) and cellular respiration markers (COX4I1, COX8A, COX7C) in slow-thawed human ovarian tissue. The trend was also confirmed by IF staining and quantitative reverse transcription polymerase chain reaction (qRT-PCR). In mouse ovarian tissue, M1 treatment significantly elevated the expression of markers associated with mitochondrial function (COX8A, ∼2.3-fold, P < 0.05), stromal integrity (ACTA2, ∼4.4-fold, P < 0.001) and proliferation (PCNA, ∼2.4-fold, ","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"25 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/P-329 The role of endometrial microbiota in the pathogenesis of chronic endometritis – A systematic review and meta-analysis","authors":"A.Y. Kilian Grote, A. Vidal, V. Vinayahalingam, B. Zagrapan, J. Pape, T. Karrer, M. Von Wolff","doi":"10.1093/humrep/deag083.665","DOIUrl":"https://doi.org/10.1093/humrep/deag083.665","url":null,"abstract":"Study question In women with infertility, does chronic endometritis associate with endometrial microbiome alterations and adverse reproductive outcomes compared to women without CE? Summary answer Chronic endometritis is linked to endometrial microbiome dysbiosis, with reduced Lactobacillus and increased pathogenic bacteria, contributing to impaired reproductive outcomes. What is known already Chronic endometritis (CE) is a subtle, often asymptomatic endometrial inflammation defined by CD138+ plasma cell infiltration. CE is increasingly recognized as a contributor to infertility, recurrent implantation failure (RIF), and recurrent pregnancy loss (RPL). Evidence suggests that CE associates with reduced Lactobacillus dominance and increased potentially pathogenic bacteria such as Streptococcus spp., Enterococcus spp., E. coli, and Ureaplasma spp., which may disrupt immune homeostasis and impair endometrial receptivity. Study design, size, duration This systematic review and meta-analysis included 22 studies comprising 4,022 women published between 2000 and 2025. CE was diagnosed via CD138 immunostaining and microbiome assessed using molecular methods. Observational designs included cross-sectional and longitudinal cohorts with sample collection from single to multiple menstrual cycles. Data were pooled to evaluate associations between CE, microbial alterations, and reproductive outcomes such as infertility, RIF, and RPL. Participants/materials, setting, methods We searched MEDLINE, Embase, Cochrane CENTRAL, Scopus, and clinicaltrials.gov (2000–2025) for studies including women of reproductive age undergoing fertility evaluation. Endometrial samples were obtained via biopsy or curettage and analyzed for CD138+ plasma cells. Microbiome profiling was performed using molecular techniques, including 16S rRNA sequencing and PCR. Data extraction, risk-of-bias assessment, and statistical analyses followed standardized protocols. Outcomes included microbial composition, prevalence of pathogenic taxa, and reproductive endpoints such as implantation success and pregnancy outcomes. Main results and the role of chance Twenty-two studies including 4,022 women were analyzed. CE was associated with reduced prevalence of Lactobacillus-dominated microbiota and increased detection of non-Lactobacillus species, particularly Streptococcus spp., Enterococcus spp., Escherichia coli, Staphylococcus spp., Ureaplasma spp., and Gardnerella vaginalis. In the meta-analysis (2,947 women), Enterococcus spp. and Ureaplasma spp. were significantly more prevalent in women with CE, whereas Streptococcus spp., E. coli, Staphylococcus spp. and G. vaginalis showed non-significant trends with substantial between-study heterogeneity. Limitations, reasons for caution Evidence is limited by heterogeneity in CE diagnostic criteria, microbiome assessment methods, and study designs. Most studies were observational with variable sample sizes and populations. Substantial heterogeneity reduces p","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"19 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/O-070 Intraovarian platelet-rich plasma in poor ovarian reserve: does route of administration influence ovarian responsiveness and feasibility?","authors":"H. Dj, D.R. Gedela, K. Chaitanya, N. Balkawade, S. Vellanki, P.K. Nayak","doi":"10.1093/humrep/deag083.070","DOIUrl":"https://doi.org/10.1093/humrep/deag083.070","url":null,"abstract":"Study question In women with poor ovarian reserve, does the route of intraovarian platelet-rich plasma (PRP) administration influence post-treatment ovarian responsiveness and reproductive feasibility? Summary answer Intraovarian PRP was associated with improved ovarian responsiveness in POSEIDON 3–4 women, with comparable downstream reproductive outcomes following laparoscopic and transvaginal administration. What is known already Poor ovarian reserve is characterised by diminished follicular activity and poor response to stimulation. Autologous platelet-rich plasma (PRP) has been proposed as a biological modulator of the ovarian microenvironment, but evidence remains limited and heterogeneous. While intraovarian PRP has been delivered via laparoscopic and transvaginal routes, comparative data evaluating whether route of administration influences ovarian or reproductive outcomes are scarce. Clarifying feasibility and comparability of delivery routes is essential before wider evaluation of efficacy. Study design, size, duration This prospective interventional cohort study was conducted between 2023 and 2025 at a tertiary fertility centre following ethics approval and trial registration. A total of 129 women with poor ovarian reserve (POSEIDON Groups 3–4) underwent intraovarian autologous PRP administration, delivered laparoscopically (n = 26) or via transvaginal ultrasound guidance (n = 103), and were followed through subsequent ovarian stimulation and reproductive outcomes. Participants/materials, setting, methods Autologous PRP was prepared from peripheral blood using a standardised double-spin protocol and injected into the ovarian cortex. Ovarian stimulation was initiated 1–3 months post-PRP. Primary outcomes focused on ovarian responsiveness, including antral follicle count (AFC), oocyte yield, number of mature (MII) oocytes, and embryo formation. Secondary outcomes included fertilisation, implantation, clinical pregnancy, live birth, and spontaneous conception. Outcomes were analysed descriptively and by route of administration. Main results and the role of chance Following PRP administration, 93% of women demonstrated an increase in AFC. The proportion of women with no detectable AFC declined from 6.9% to 0% (p = 0.003). Cycles with no oocyte retrieval decreased from 13.5% to 1.8% (p = 0.001), absence of mature oocytes from 12.5% to 2.7% (p = 0.007), and failure of embryo formation from 72.6% to 22.1% (p < 0.001). Among women proceeding to frozen embryo transfer (n = 45), implantation, clinical pregnancy, and live birth rates were 31.3%, 53.3%, and 46.6%, respectively. No statistically significant differences were observed between laparoscopic and transvaginal PRP administration across ovarian or reproductive outcomes, indicating comparable feasibility of both routes. Limitations, reasons for caution The study lacked a non-PRP control group, was non-randomised with unequal subgroup sizes, and was not designed to establish efficacy. ","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"41 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/O-304 Past","authors":"P. Thompson","doi":"10.1093/humrep/deag083.302","DOIUrl":"https://doi.org/10.1093/humrep/deag083.302","url":null,"abstract":"not submitted by author","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"29 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148400985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/P-149 Impact of extended in vitro maturation on oocyte developmental potential: a matched-pair analysis of 65,167 oocytes","authors":"A. Alarcón, E. Padilla, P. González, J. García, C. Aceituno, C. Pérez, L. Medrano","doi":"10.1093/humrep/deag083.485","DOIUrl":"https://doi.org/10.1093/humrep/deag083.485","url":null,"abstract":"Study question Does in vitro completion of nuclear maturation in MI-derived oocytes prior to ICSI affect fertilization and blastocyst development compared with in vivo–matured MII oocytes? Summary answer MI-derived oocytes maturing in vitro show significantly poorer fertilization and blastocyst development, although their use may still increase cumulative blastocyst yield in selected patients. What is known already Oocytes retrieved at metaphase I (MI) can complete nuclear maturation in vitro and reach metaphase II (MII) before ICSI, but their true developmental competence remains controversial. In clinical practice, these oocytes are frequently discarded at denudation due to uncertainty regarding their fertilization and developmental potential and concerns that delayed nuclear maturation may not be accompanied by adequate cytoplasmic maturation. Previous studies have reported inconsistent outcomes, often limited by small sample sizes, heterogeneous laboratory protocols, and inadequate control of key confounders such as female age, oocyte origin, and center-related variability. Consequently, large, well-controlled multicenter studies focusing on MI-derived oocytes are scarce. Study design, size, duration Retrospective multicenter matched-pair cohort study including 65,167 oocytes from IVF/ICSI cycles performed between 2019 and 2026. Propensity score matching generated 1,689 balanced pairs comparing in vivo–matured MII oocytes with MI-derived oocytes completing maturation in vitro prior to ICSI. Participants/materials, setting, methods After retrieval, oocytes were incubated with cumulus cells, then denuded and cultured until ICSI. MI oocytes were classified as in vitro–matured MII only if first polar body extrusion was observed immediately before ICSI. Matching accounted for female age, oocyte origin (own or donor), oocyte type (fresh or vitrified), and center. Fertilization, degeneration, and blastocyst development were analyzed using McNemar, paired Wilcoxon, and Cochran’s Q tests, with odds ratios calculated from discordant pairs. Main results and the role of chance After matching, groups were identical across all covariates. MI-derived oocytes maturing in vitro showed significantly higher non-fertilization rates compared with in vivo–matured MII oocytes (27.8% vs. 13.4%; adjusted OR [aOR]=2.5, 95% CI 2.0–3.0) and increased abnormal fertilization (9.8% vs. 8.8%; aOR=1.4, 95% CI 1.1–1.9). Normal fertilization was significantly reduced (53.6% vs. 67.9%). Post-ICSI degeneration rates did not differ significantly between groups (9.8% vs. 8.9%; aOR=1.2, 95% CI 0.9–1.6). Blastocyst formation was markedly lower in in vitro–matured oocytes (19.8% vs. 36.3%), with a higher risk of failure to reach the blastocyst stage (aOR=2.4, 95% CI 2.0–2.8). All global tests were statistically significant (p < 0.001), except degeneration. The consistency between crude and adjusted estimates and the narrow confidence intervals indicate robust findings unlikely","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"37 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L26/O-286 Impact of IVF versus ICSI on the likelihood of obtaining at least one usable blastocyst in patients who previously failed to form a blastocyst","authors":"G. Majumdar, A. Sarkar, S. Mittal Gupta, A. Majumdar","doi":"10.1093/humrep/deag083.284","DOIUrl":"https://doi.org/10.1093/humrep/deag083.284","url":null,"abstract":"Study question Does changing the fertilization method in a subsequent IVF cycle increase the likelihood of obtaining at least one usable blastocyst in patients who previously failed to form any usable blastocysts Summary answer Changing from IVF to ICSI or vice versa did not improve the likelihood of obtaining at least one usable blastocyst after a prior blastocyst failure. What is known already The ability to reach the blastocyst stage is influenced by several factors including maternal age, oocyte and sperm quality, and laboratory culture conditions. The mode of fertilization - IVF versus ICSI - may also affect embryo development. In patients without male factor infertility, conventional IVF has been shown to be superior to ICSI, generally yielding higher numbers of usable blastocysts due to natural sperm selection and greater oocyte utilization. However, it is unclear whether changing the fertilization approach can improve outcomes for patients with a prior failure to form blastocysts. Study design, size, duration This was a retrospective cohort study evaluating patients undergoing IVF/ICSI at a single tertiary fertility center between January 2023 and July 2025. Patients undergoing a second treatment cycle following a previous cycle with no usable blastocysts were included in the study. Participants/materials, setting, methods Of 157 eligible patients, those with split insemination in the first cycle (n = 5) and those requiring ICSI due to sub-optimal semen parameters in the second cycle (n = 47), were excluded. The final analysis included 105 patients eligible for either IVF or ICSI. Patients were categorized into two groups: 1. Change in fertilization method (IVF→ICSI or ICSI→IVF) 2. Same method repeated The primary outcome measure was the proportion of patients with at least one usable blastocyst in the second cycle. Main results and the role of chance Overall, 60% (63/105) of patients who failed to produce a blastocyst in their previous cycle yielded at least one usable blastocyst in their subsequent cycle. Among patients with a prior IVF cycle, switching to ICSI resulted in significantly lower fertilization rates compared with repeating IVF (53.5% vs. 79.6%; p = 0.0003). However, no significant differences were observed thereafter in top quality day 3 embryo rate and usable blastocyst formation rate in both the groups. Although a higher proportion of patients achieved at least one usable blastocyst in the IVF→ICSI arm compared to the IVF→IVF arm (66.7% vs. 52.6%), this difference was not statistically significant. In patients with a prior ICSI cycle, changing to IVF did not improve fertilization (58.9% vs. 56.7%), day-3 embryo quality (42.8% vs. 56.1%; p = 0.11), usable blastocyst formation rate (24.2% vs. 25.8%), or the probability of obtaining at least one usable blastocyst (63.2% vs. 63.3%). Limitations, reasons for caution This study is limited by its retrospective design, small subgroup sample sizes, and lack of randomization, which","PeriodicalId":13003,"journal":{"name":"Human reproduction","volume":"35 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148401056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}