Human Reproduction

Background: Literature on the role of thermal discomfort (heat- and cold-stress) on in-vitro fertilization (IVF) outcomes are scarce and inconclusive. This multi-center research examines association between heat stress and IVF treatment outcomes in Andhra Pradesh, which is prone to year around chronic heat stress. Methods: IVF data were abstracted from clinical chart review of all patients from three IVF from centers 2019 to 2023, which included time-stamped data on each IVF procedure, demographics and pre-existing comorbidities. Weather data were acquired from the National Climatic Data Center (NCDC). IVF outcomes were modelled with respect to time-lagged exposure to ambient temperature stratified by hyper- and hypo-thermic conditions using Poisson and logistic regressions depending on the scale of IVF outcomes adjusting for confounders. Results: Heat stress peaked in June, which corresponded with elevated number of spontaneous abortions/miscarriage (SAM). Under hypo- and hyper-thermic conditions a unit increase ambient temperature was associated with an 11% higher and an 8% lower number of oocytes retrieved, respectively. Adjusting for confounders, a 10 degree F increase in two-day lag heat stress was associated with a 30% higher odds of SAM (odds ratio ~ 1.03; 95% CI = 1.001 to 1.068; p-value < 0.043), and odds of PTB were 3 times higher when three day-lagged heat index (HI) was greater than 35 degree C (odds ratio 1.13 to 7.99; p < 0.05). Conclusion. Our findings warrant strategies to engage IVF patients in mitigating their exposure to thermal discomfort before and during the treatment.

Objective To examine the effects of combined oral contraceptive (OC) use on clinical markers of ovarian reserve by comparing Anti-Muellerian Hormone (AMH), antral follicle count (AFC), and ovarian volume (OV) before and after starting or stopping OC. Methods This analysis is based on data from a prospective cohort study conducted at the University Hospital Tubingen, Germany, as part of the IRTG-2804 project. A total of 54 healthy women were included and categorized into three groups based on their OC use status: OC starters (n = 12), stoppers (n = 16), and long-term OC-users (n = 26). Each participant underwent a transvaginal ultrasound (including AFC and OV) and serum sampling (including AMH) at two time points (S1 and S2), three to six months apart. OC starters were assessed first during the early follicular phase (day 1-7) and then during active OC intake (day 8-21), while stoppers were assessed in the reverse order. Long-term users were assessed twice during active OC intake. Results OC stoppers showed significant within-group increases in all ovarian reserve markers, including AMH ({Delta} = 2.57 ng/mL, p < .001), AFC ({Delta} = 3.88, p = .004), and OV, which almost doubled (1.94-fold increase; 95% CI [1.35, 2.80], p < .001). In contrast, OC starters exhibited a significant decline in AMH ({Delta} = -1.25 ng/mL, p = .013), but no changes in AFC or OV. No significant longitudinal changes were observed among long-term OC users. Conclusion AMH levels decrease after starting OC use whereas AFC and OV are not affected. In contrast, AMH, AFC, and OV recover within three to six months after stopping OC, suggesting a reversible suppression of ovarian reserve markers during OC use. These findings are clinically relevant for fertility counseling and for the interpretation of ovarian reserve markers in women using hormonal contraception.

Background The use of Assisted Reproductive Technology (ART) is increasing worldwide. These treatments involve ovarian stimulation to enable multiple follicle recruitment, hence inducing supraphysiological estrogen levels. While most long-term follow-up of women undergoing ART has concerned cancer incidence, the long-term safety regarding cardiovascular and metabolic diseases remains under-explored. This study was performed to assess the risk of acute myocardial infarction, cerebral ischemic conditions, intracranial hemorrhage, type 2 diabetes mellitus, heart failure, aortic aneurysm or dissection, and chronic kidney disease in women that conceived with ART, and to investigate the role of the underlying infertility and its risk factors. Methods and Findings Swedish national registers allowed us to follow a nationwide cohort of 380,756 women from their first birth between 1992 and 2002 until the end of 2023. The safety of ART was evaluated by comparing women with infertility who conceived with and without ART, while adjusting for baseline differences in age, body mass index, country of origin, socioeconomic factors, pre-existing comorbidity, smoking and year. The role of infertility was additionally explored by comparing all women with and without infertility adjusting for age, as well as the aforementioned baseline characteristics. Cumulative risks were plotted using inverse-probability weighted Kaplan-Meier curves. To facilitate the comparison of groups we also estimated risk differences and ratios at 10-, 20-, and 30-years of follow-up. Use of ART was not associated with cardiovascular disease except for an excess risk of cerebral ischemic conditions, with a 30 year risk ratio of 1.43 (1.09; 1.89). With the exception of cerebral ischemic conditions, intracranial hemorrhage, aortic dissection, and chronic kidney disease, women with a history of infertility exhibited consistently higher risk of all outcomes, adjustment for differences in baseline characteristics explained some but not all of these elevated risks. Conclusions With the exception of ischemic cerebral conditions, the findings provide reassurance regarding the long-term cardiometabolic safety of ART use, while adding to the growing literature suggesting that infertility can act as a marker of womens cardiovascular and metabolic disease.

Background Delineating the cellular origins of extracellular vesicles (EVs) enables the detection of clinically relevant changes in dynamic and complex tissues, such as the endometrium, which are not characterizable through single biomarker assays. Transcriptome deconvolution into cellular composition using deep learning methods provides a means to explore this complexity. However, such computational methods have not been previously applied to EV bulk transcriptomes, and their efficacy in profiling EV population changes and concordance to tissue throughout the menstrual cycle remains unknown. Methods This observational cross-sectional study utilized a deconvolutional generative deep learning algorithm, BulkTrajBlend, trained on a comprehensive human endometrial single-cell RNA sequencing (scRNA-seq) atlas. The model was applied to deconvolve paired bulk transcriptomes from endometrial tissue and uterine fluid EVs (UF-EVs) across the proliferative (P, n=4), early-secretory (ES, n=5), mid-secretory (MS, n=5), and late-secretory (LS, n=5) phases from healthy, fertile women. To validate generalizability, independent UF-EV datasets (ES, n=12; MS, n=12) obtained via different laboratory protocols were included. Deconvolved pseudo-single-cell (pSC) profiles from UF-EV data were subsequently integrated with Visium spatial transcriptomics slides of human endometrium (P, n=2; MS, n=4; ES, n=2). Results We developed a foundation model-based approach utilizing self-supervised learning to determine the cellular origin of EVs from their transcriptomic profiles. By mapping the generated pSC profiles to spatial transcriptomic data, we evaluated spatial origins of EVs. The statistical analysis demonstrated that UF-EV transcriptome deconvolution reflects the dynamic changes in the cellular composition of endometrial tissue across the menstrual cycle phases. The ability to distinguish accurately between proliferative and decidualizing menstrual cycle phases (ROC-AUC = 0.98) using cellular profile of deconvoluted UF-EVs transcriptome enables non-invasive profiling of endometrial tissue. Conclusions Our findings indicate the feasibility of determining endometrial tissue cellular composition using UF-EV transcriptomics. This methodology enables refined, non-invasive endometrial testing, avoiding invasive biopsy procedures. Based on deconvolution results, we are able to correlate UF-EV content to tissue, and distinguish between menstrual cycle phases. These results build toward a multifactorial screening method for abnormalities within the endometrium.

Study question: Does twin status and zygosity (monozygotic vs. dizygotic; same-sex vs. opposite-sex) predict fertility outcomes and intergenerational reproductive patterns compared with singletons? Summary answer: Among females, dizygotic twins had modestly higher completed fertility than singletons and monozygotic twins and were more likely to have a twin birth. Fertility did not differ meaningfully among males. These differences were restricted to the twin generation and did not persist in the next generation, indicating sex-specific and generation-specific effects rather than intergenerational transmission. What is known already: Dizygotic twinning is associated with heritable hyperovulation and higher natural fertility but less is known about whether being a twin or zygosity influences reproductive outcomes across generations. Study design, size, duration: A population-based longitudinal cohort study using part of the Finnish Twin Cohort and national population registers. Participants included monozygotic (MZ; N = 4,068), same-sex dizygotic (SSDZ; N = 8,890), opposite-sex dizygotic (OSDZ; N = 8,474) twins, and singleton controls (N = 1,193,404) born between 1945-1957 (total N =1,254,103; 49.1% female), their mothers, their children, and their grandchildren. Participants/materials, setting, methods: Fertility outcomes (number of biological children, age at first birth, childlessness, multiple births) were derived from Finnish population registers. Analyses followed a preregistered plan (https://osf.io/qbwv3) Main results and the role of chance: Differences in fertility between singletons and twins were modest and varied by sex and zygosity. Differences were observed generally in the mothers of twins and female twins themselves, with limited differences in the offspring of twins as compared to the offspring of singletons. Twins were slightly older at first birth, had fewer total biological offspring, but were more likely to have a twin birth. Dizygotic twins in particular differed from monozygotic twins and singletons. Limitations, reasons for caution: Findings are limited to individuals born in mid-20th-century Finland and thus generalizability to recent populations or non-Nordic contexts may be restricted. Further, analyses are observational, and causal inference is limited due to alternative motivation behind fertility rates like social or cultural reasons. Wider implications of the findings: These findings suggest that zygosity and sex interact to shape reproductive outcomes, offering insight into genetic and environmental contributions to fertility. They highlight the value of large twin cohorts for studying intergenerational reproductive trends and the representativeness of twins in population-based fertility research.

Abstract Purpose: Published clinical outcome data on preconception carrier screening (PCS) in Central Asia are limited. We report the first clinical implementation study from Uzbekistan of a whole-exome sequencing (WES)-based multi-platform PCS program combining exome sequencing with targeted SMA, FMR1, and DMD assays. Methods: We retrospectively analyzed anonymized data from 65 individuals (19 couples, 27 singletons) screened at IMC Genomics, Tashkent, between January 2024 and May 2026. WES covering the protein-coding regions of approximately 20,000 genes was followed by exome-wide bioinformatics filtering and clinical geneticist interpretation. Partly overlapping cohorts underwent SMA carrier screening (n=179), FMR1 CGG-repeat analysis in females (n=155), and DMD deletion/duplication testing in preconception females (n=29). Variants were classified by ACMG/AMP criteria against gnomAD v4.1. Results: Sixty-one of 65 WES-screened individuals (93.8%; 95% CI 85.2 - 97.6%) carried at least one reportable variant (152 instances across 126 genes). Four of 19 couples (21.1%; 95% CI 8.5 - 43.3%) were concordant for pathogenic or likely pathogenic variants in the same autosomal recessive gene; two were referred for preimplantation genetic testing for monogenic disease. SMA screening identified four carriers, including two 2+0 silent carriers; FMR1 analysis identified one intermediate allele; DMD MLPA identified no exonic rearrangements. Conclusion: This first reported WES-based multi-platform PCS program in Uzbekistan was feasible and clinically informative, identifying actionable couple-level reproductive risks and supporting structured implementation of reproductive genetic screening in Central Asia.

Consanguinity is a reproductive union between individuals who share a recent common ancestor. These unions are common in many regions of the world and increase the burden of rare recessive disorders by elevating autozygosity in offspring. Current reproductive genetic screening focuses on a limited set of known pathogenic variants, leaving most recessive risk unaddressed. Here we argue that embryo-level autozygosity, quantified as the fraction of the genome in long runs of homozygosity (FROH), is a potentially actionable genomic biomarker that can be integrated into routine preimplantation genetic testing as a homozygosity-informed embryo-prioritization framework (PGT-H) that can be layered onto existing embryo biopsy workflows when couples are already undergoing IVF with PGT-A or PGT-M. Using forward simulations of first-cousin and double-first-cousin couples, we show that siblings conceived by the same couple span a wide range of FROH; selecting the lowest-FROH candidate from a cohort of five embryos reduces FROH by approximately 40% on average. Combining these reductions with empirical effect-size estimates, we estimate that for first-cousin couples this strategy could reduce risk of intellectual disability by roughly 35-45% (corresponding to an absolute risk reduction of about 1.8-2.2%) and potentially reduce excess recessive disease burden, while also modestly reducing risk of common diseases such as type 2 diabetes. We outline how existing PGT-A and PGT-M workflows could potentially be extended to report embryo-level FROH and discuss ethical and counseling considerations. Autozygosity-based embryo prioritization offers a principled way to address a component of recessive risk that current variant-centric approaches miss.

Background: Placenta accreta spectrum (PAS) is an important cause of severe maternal morbidity. Although prior cesarean delivery is a well-established risk factor, PAS also occurs in women without prior cesarean section (CS), in whom risk may be underestimated. This study evaluated routinely available clinical factors associated with PAS in this population and developed a clinical-history-based prediction model. Methods: We conducted a retrospective cohort study of women without prior CS who delivered at Peking University Third Hospital, China, from January 1, 2022, to December 31, 2023. PAS was diagnosed according to the 2019 International Federation of Gynecology and Obstetrics clinical and/or histopathological criteria. Multivariable logistic regression was used to identify independent risk factors. Model performance was assessed using receiver operating characteristic curves, calibration, decision curve analysis, and stratified 5-fold cross-validation. Analyses were repeated after stratification by placenta previa status. Results: Among 11,148 women without prior CS, 236 had PAS. Independent risk factors in the overall cohort were placenta previa, operative hysteroscopy, uterine curettage, in vitro fertilization, and multifetal pregnancy. The overall clinical prediction model showed an area under the curve of 0.838 (95% confidence interval, 0.81-0.87), with stable performance in internal validation. In stratified analyses, model discrimination was lower among women without placenta previa (area under the curve, 0.734) and those with placenta previa (area under the curve, 0.647). Conclusions: In this single-center cohort, routinely available clinical history was associated with PAS risk among women without prior CS. The proposed model may help identify patients who warrant targeted PAS imaging or specialist assessment, but external validation and integration with imaging features are needed before broad clinical implementation.

Introduction: Preeclampsia (PE) is a leading cause of maternal and neonatal morbidity and mortality, and low-dose aspirin (LDA) prophylaxis is the cornerstone of evidence-based prevention. Despite guideline recommendations, LDA adherence remains poor, with 10-25% of moderate-risk patients taking aspirin. Objective personalized risk stratification using biomarkers has been shown to motivate behavior change in other disease contexts. Survey data suggest that patients are more motivated to take aspirin if informed by an objective predictive test. Here, we report real-world LDA adherence among patients who received a high-risk result from a cell-free RNA (cfRNA) PE risk prediction test. Methods: This retrospective, observational survey study included asymptomatic patients of advanced maternal age (AMA; [&ge;] 35 years at delivery) with singleton pregnancies without USPSTF-defined preexisting high-risk conditions for PE who received the cfRNA PE risk prediction test. Patients who opted in to receive text message surveys were asked about LDA use following receipt of test results. High adherence was defined as reporting LDA use on at least 6 of 7 days per week at least 85% of the time surveyed. The primary analysis included patients with a high-risk test result and at least one LDA frequency survey response following receipt of test result. The observed proportion of adherent patients was compared to a baseline estimate of 25% using an exact binomial test. Results: Of 166 patients who received a cfRNA PE risk prediction test result, 48 (28.9%) received a high-risk result. Of these, 29 (60%) opted in and responded to at least one survey, constituting the primary analysis population. Twenty-seven of the 29 (93.1%; 95% CI: 78.0-98.1%) were classified as highly adherent, significantly higher than the 25% baseline adherence estimate for moderate-risk patients (p < 0.0001). Conclusion: Among surveyed patients who received a high-risk cfRNA PE test result, the proportion classified as highly adherent to LDA (93%) substantially exceeded published estimates of adherence in a similar patient population and met the clinically meaningful threshold of [&ge;] 80% associated with reduced risk of preterm preeclampsia. These findings indicate that objective and personalized biomarker risk testing may be a powerful driver of behavior change that current guidelines have failed to produce.

Conventional semen cryopreservation involves equilibration at 4{degrees}C and optimum freezing rates. We hypothesized that a cholesterol-based semen extender obviates the need for equilibration, minimizing total processing time for semen cryopreservation. Experiments were conducted to determine the effects of semen extender (egg yolk- or cholesterol-based) and freezing method (routine or fast) on post-thaw sperm characteristics and fertility of beef and bison semen. In Experiment 1, beef semen diluted in tris-egg yolk-glycerol (TEYG) or cholesterol-cyclodextrin tris-glycerol (CCTG) extender underwent routine or fast freezing method. Cholesterol from animal and plant origins were compared. The routine method included 90-min equilibration at 4{degrees}C and routine freezing (RE-RF, total time 97 min) whereas the fast method included no equilibration and fast freezing (NE-FF, total time 14 min). Post-thaw sperm quality was assessed by CASA, and in vitro fertilization. Post-thaw sperm motility was not affected by the origin of cholesterol (animal or plant), but was lowest in the TEYG NE-FF group (24% vs 43-51%, P < 0.05). In vitro cleavage and blastocyst development rates did not differ between RE-RF and NE-FF groups. In Experiment 2, bison semen was diluted in TEYG or plant-CCTG extender and frozen as in Experiment 1. Post-thaw sperm motility was lowest in the TEYG NE-FF group (10% vs 39-51%, P < 0.05). In Experiment 3, beef semen diluted in TEYG or plant-CCTG extender underwent either a routine (RE-RF) or modified freezing (NE-RF, total time 25 min) method. Post-thaw sperm characteristics did not differ between extenders but were greater using routine freezing (RE-RF) compared to the modified method of freezing (NE-RF). Pregnancy rates were similar between extenders (TEYG vs plant-CCTG) using the modified freezing method without equilibration and insemination at 72 h after progesterone device removal. In conclusion, beef and bison semen diluted in cholesterol-based extender may be cryopreserved without equilibration.

Objectives: To evaluate if direct access to a Pregnancy Early Access Center (PEACE) improves the timeliness and efficiency of pregnancy loss care. Methods: We conducted a retrospective cohort study of patients diagnosed with EPL from January 2017 to December 2022 within a single healthcare system. We included EPL patients treated with procedural or medication management who had been assessed for a related early pregnancy complaint in the thirty days prior. The exposure was direct utilization of PEACE (yes/no) between first EPL symptom visit and EPL management. The primary outcome was "care latency" defined as days from initial presentation for concerning early pregnancy symptoms to initiation of active management. Secondary outcomes included "care continuity," the number of care teams encountered, "care efficiency," the number of patient encounters, and the type of EPL management received. Results: The evaluable cohort included 2151 individuals, with 36.5% patients of Black race and 30.3% publicly insured. A total of 885 (41.1%) received any EPL care at PEACE and 246 (11.4%) initiated their care at PEACE. Patients initiating care through PEACE experienced a 5-day reduction in care latency compared to patients who did not access PEACE. Adjusting for age, race, and insurance type, patients whose index EPL visit was with PEACE initiated their treatment twice as quickly as those who never saw PEACE (aHR 2.36 [95% CI, 2.05-2.71]). Care efficiency (median 2 [1-3] encounters) and care continuity (median 4.5 [4-7] care teams) were also improved by an index visit with PEACE when compared with controls (3 [2-4] and 6 [4-8] p<0.01), respectively). Conclusions: The Pregnancy Early Access Center (PEACE) model is associated with reduced care latency and improved efficiency and continuity when compared with routine care. PEACE reduces barriers to timely, patient-centered early pregnancy care.

Impaired seminal redox balance is a main factor that contributes to male fertility disorders and reduced sperm survival during storage. Although several methods are available to measure antioxidant and reactive oxygen species (ROS) levels, their cost and complexity limit their use in routine sperm analysis. Recently, assessment of oxidation-reduction potential (ORP) has emerged as a convenient and comprehensive method for evaluating seminal redox status. While the implications of seminal ORP in humans have been extensively explored, its use in other species is limited. In this study, we explored the relationship between boar seminal ORP and sperm quality and its dynamics during liquid preservation. We found that the ORP of the porcine ejaculate was lower than that of the seminal plasma, while both parameters were correlated with the total antioxidant capacity (TAC) of seminal plasma. Sperm concentration and seminal pH influenced the seminal ORP, with lower values observed in ejaculates with higher sperm concentration and pH. Notably, a more oxidative seminal environment (characterized by high ORP or low TAC) was correlated with high mitochondrial activity and sperm velocity in fresh samples, which might be explained by increased ROS production by sperm mitochondria. Our results also show that seminal ORP increased during three days of liquid storage, while the ORP of the extender did not change significantly during the same period. Our findings advance our understanding of the implications of redox status in porcine sperm biology and pave the way for the broader application of ORP measurement in animal andrology. HighlightsO_LIThe ejaculates oxidation-reduction potential is lower than that of seminal plasma C_LIO_LISeminal oxidation-reduction potential is correlated with total antioxidant capacity C_LIO_LISeminal redox status is influenced by sperm concentration and semen pH C_LIO_LIAn oxidative seminal environment is correlated with high sperm metabolism C_LIO_LISeminal oxidation-reduction potential increases during 3 days of liquid storage C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/726780v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@18fd914org.highwire.dtl.DTLVardef@f4f179org.highwire.dtl.DTLVardef@1195e32org.highwire.dtl.DTLVardef@7760ad_HPS_FORMAT_FIGEXP M_FIG C_FIG

Background: Intrauterine contraceptives (IUCs) are effective, but effects on genital inflammation among women living with HIV (WLHIV) by antiretroviral therapy (ART) use are unclear. We evaluated the longitudinal effects of copper IUC (C IUC) and the levonorgestrel intrauterine system (LNG IUS) on cervicovaginal cytokine profiles in a secondary analysis of a randomized trial (NCT01721798, 2013 to 2016). Methods: Cervicovaginal secretions were collected from 100 WLHIV (non ART users; ART users) randomized 1:1 to C IUC or LNG IUS. Twenty eight cytokines were measured prior to insertion and 3 and 6 months post insertion. Cytokine concentrations at each follow up visit were compared with baseline, using participant fixed effects models stratified by ART status. Results: At enrolment, non ART users had higher average concentrations of most cytokines (21/28) than women using ART. Among non-ART users, IUC use was not associated with cytokine increases; only MCP1 increased significantly at 3 months among C IUC users (log10 geometric mean ratio 0.77, 95%CI 0.38 to 1.17), while none increased with LNG IUS use. Among ART users, C IUC insertion resulted in broad and sustained cytokine increases at both 3 (16/28) and 6 months (15/28). At month 3, the largest increases in log10 geometric mean were observed for IL6 (1.04, 0.72 to 1.36), RANTES (0.97, 0.54 to 1.40), MCP1 (0.71, 0.46 to 0.96), MIP1; (0.66, 0.37 to 0.94), and GCSF (0.63, 0.36 to 0.89), which was maintained until month 6. Cytokine changes following LNG IUS insertion were minimal (IL5, month 3). Conclusions: Among ART users, C IUC is associated with increases in cervicovaginal cytokines, across functional classes. This supports LNG IUS as a less inflammatory option for WLHIV to minimize genital immune activation.

Background Planned caesarean birth (CB) is an increasingly utilised intervention, observed in almost 1 in 6 first-time mothers giving birth in the UK in 2023-24. Outcomes of planned (or actual) CB have been compared with planned (or actual) vaginal birth (VB) in a UK national guideline, but the scope of the comparison does not fully reflect the range of outcomes of interest to stakeholders. This review provides a comprehensive synthesis of outcomes of planned or actual CB with planned or actual VB to shape information resources which support informed birth planning. Methods The UK NICE Caesarean Birth Guideline NG192 evidence review of outcomes associated with planned CB (or actual CB where no planned CB data was available) was updated and expanded to incorporate additional outcomes prioritised by stakeholders. Results A total of 33 new study reports were combined with 32 reports previously included in NG192. All new reports were observational cohort studies or systematic reviews at low risk of bias. Only 3 studies reported outcomes of planned CB compared with planned VB (regardless of actual mode of birth), whereas all remaining studies reported actual VB outcomes. Planned CB was followed by more maternal infection (wound infection, mastitis, endometritis and urinary tract), venous thrombosis and lower neonatal unit admission rates than a planned VB. In the long-term, CB was linked to one or more sexual problems (insufficient lubrication and dyspareunia) being more common, future pregnancy being less common, and infertility being more frequent than after VB. For offspring, infant urinary tract infection after any CB, gastrointestinal tract infections and autism after planned CB were more common compared with VB. New findings highlight conflicting reports on childhood asthma and type 1 diabetes risk after planned CB, suggesting that prior positive associations may be explained by confounding. Existing evidence in NG192 suggests that cardiac arrest, maternal death and hysterectomy are more common after planned CB, but arise from studies at high risk of bias. NG192 also reports that placenta accreta and uterine rupture in a future pregnancy are more common after any CB. No new evidence was identified on these outcomes. Conclusion This review provides stakeholder-relevant information to populate decision-support materials on outcomes of planned (and actual) CB compared with planned (and actual) VB. The existing evidence base lacks data on long-term outcomes of planned (rather than actual) VB.

ObjectivesLow serum testosterone (T) in men with obesity suggesting T deficiency may be misinterpreted by confounding changes in serum SHBG, Ts circulating carrier protein. Measuring or calculating "free" testosterone (FT) concentrations to define a low T is problematic as cFT is not a valid analytical variable lacking certified standard, quality control or reference range. We developed a novel metric, Scaled Testosterone (ST), comparing standardized serum T (LCMS) and SHBG without invoking hypothetical serum T fractions. MethodsSerum T and SHBG in men (n=10,027) pooled from three population-based studies in Australia were expressed as standardized (Z) scores (ZT, ZSHBG) and their difference ST = ZT-ZSHBG. ST was evaluated in a clinical trial of 51 men with severe obesity undergoing 1 year of diet-induced weight loss. ResultsZT and ZSHBG displayed linear correlation (r=0.44, 10-11) with ST approximating zero (-0.33 {+/-}2.14 SD). In non-obese men with low serum T suggestive of organic hypogonadism displayed very low ST indicating ST can evaluate whether a low serum T is proportionate to a concomitant serum SHBG. In men with obesity, low pre-treatment serum T and SHBG both increased during diet-induced weight loss with no change in serum LH while ST which remained within standard limits at each time. ConclusionsThe low serum T in men with obesity may better be considered as the pseudo-hypogonadism of obesity comprising low serum T with proportionately low serum SHBG in the presence of normal serum LH {+/-} FSH serving as a tissue androgen sensor.

Endometriosis is a steroid-dependent gynecologic disease characterized by progesterone (P4) resistance, subfertility/infertility, and pelvic pain; however, the molecular mechanisms underlying impaired P4 responsiveness in endometriosis tissue are not fully understood. RE-1 silencing transcription factor (REST), a transcriptional regulator implicated in steroid hormone signaling, has emerged as a potential mediator of P4 responsiveness. Here, we investigated the role of REST in endometriosis using human tissues and a uterine-specific Rest conditional knockout mouse model. Immunohistochemical analysis of eutopic endometrium and ectopic lesions from patients with endometriosis revealed significantly reduced nuclear REST expression compared with control endometrium, suggesting loss of functional REST in disease. To assess the physiological consequences of REST deficiency, uterine-specific Rest knockout (Rest d/d) mice were generated. Rest d/d females exhibited progressive subfertility and hyper-estrogenic uterine tissue characteristics that displayed a blunted responsiveness to P4 treatment. Loss of Rest selectively altered expression of P4-responsive genes associated with endometriosis pathology, despite preserved P4 receptor expression. Following induction of experimental endometriosis, female mice that developed endometriotic-like lesions using Rest-deficient donor tissue developed significantly larger lesions that were less responsive to P4 treatment compared to lesions induced using control tissue. Mechanical sensitivity was modestly increased in mice receiving Rest-deficient tissue, whereas vaginal hyperalgesia was unaffected. These findings identify loss of nuclear REST as a feature of endometriosis and support a role of REST in subfertility, lesion progression, and blunted response to P4. REST may represent a novel molecular contributor to altered P4 responsiveness and a potential therapeutic target in endometriosis. Significance StatementEndometriosis is a common disease in women characterized by altered steroid hormone signaling, infertility, and pelvic pain. RE-1 silencing transcription factor (REST) is a candidate regulator of steroid hormone signaling in gynecologic disease but a role in endometriosis pathophysiology remains unexplored. To fill this knowledge gap, our study utilizes human endometrial and endometriotic tissues coupled with a conditional knockout mouse model for uterine Rest deficiency. We show that REST is significantly reduced in eutopic and ectopic endometrial tissue from women with endometriosis and that deletion from mouse uterine tissue recapitulates clinical characteristics in women with endometriosis including progesterone resistance, sub-fertility and pelvic pain. These findings will further guide future research to understand impaired steroid signaling in the pathophysiology of endometriosis.

Endometrial receptivity assessment currently requires invasive tissue biopsy, yet recent randomized trials have questioned the clinical utility of biopsy-based approaches. Here we present EndoTwin-W, a four-layer mechanistic computational model that simulates human endometrial remodeling from hormone inputs through receptor binding, pathway scoring, and continuous-time Markov chain cell-state transitions across 17 cell states. Transition rates were optimized against scRNA-seq and microarray data, then validated by 5-fold cross-validation on an independent bulk RNA-seq cohort (n=236 biopsies), achieving significant correlations for 16 of 17 cell states (mean Spearman r = 0.505) with benchmark dominance over three null models for 13 of 17 states. The model identifies glycodelin-A (PAEP) and CA-125 (MUC16) as mechanistically grounded candidate circulating biomarkers capturing two principal receptivity failure modes: inadequate decidualization and excessive inflammation. Hill-function prediction of serum glycodelin-A shows strong rank-order calibration (Spearman rho = 0.833, p = 0.010). Cross-condition held-out validation against 9 independent datasets (244 samples) achieves significant concordance in 5 of 9 datasets (median rho = 0.435). A cross-dataset receptivity index analysis across 18 GEO datasets (21 comparisons) demonstrates mean AUC = 0.599 with correct direction in 76% of analyses, including significant RNA-seq validation (AUC = 0.770, p = 0.003). The divergence between predicted and measured biomarker values defines a Progesterone Resistance Score quantifying decidualization deficit and inflammation burden. EndoTwin-W provides a mechanistic framework and candidate blood-based biomarkers for receptivity assessment; prospective paired serum-tissue validation is required before clinical use. Author SummaryAssessing whether the uterine lining is ready for embryo implantation usually requires an invasive biopsy that is costly and cannot be repeated every cycle. We built a computer model called EndoTwin-W that simulates how ovarian hormones reshape the endometrium through hormone receptors, intracellular signaling, and changing cell states across the menstrual cycle. When we tested the model against published gene-expression datasets from hundreds of patient samples, it matched known endometrial cell states in 16 of 17 categories. Our main finding is that two blood proteins, glycodelin-A and CA-125, may serve as non-invasive markers of receptivity. Glycodelin-A reflects decidualization; CA-125 reflects inflammation. When the models predictions disagree with measured blood levels, the mismatch defines a two-dimensional progesterone resistance score that may help explain why some patients do not respond to progesterone despite normal hormone levels. We provide an open research website (https://endotwin-w.com: mirror: https://endotwinw.com) for exploration, but prospective clinical studies are still needed before this approach could guide patient care.

Background Fertility rates in Australia have been declining over recent decades, reaching a record low total fertility rate of 1.48 births per woman in 2024. Concurrently, vasectomy remains widely accessible and increasingly normalised as a permanent contraceptive option. Despite extensive commentary on falling birth rates, no contemporary Australian study has examined vasectomy rates relative to birth rates over time. We aimed to compare population level vasectomy and birth rates across Australian jurisdictions and age groups. Study design Nationwide retrospective time-series study. Retrospective population-based study using Medicare Benefits Schedule item 37623 to identify vasectomy procedures performed between July 2015 and December 2024. Rates were calculated per 100,000 male population using quarterly Australian Bureau of Statistics (ABS) population estimates and summarised as rolling 12-month averages. Birth rates were derived using matched ABS data for women across equivalent age strata (18-24, 25-34, 35-44 years). Results: Vasectomy rates increased nationally from 32 per 100,000 in 2016 to 55 per 100,000 in 2023 before declining modestly in 2024. Birth rates declined from 5,200 to 3,800 per 100,000 over the same period. Trends were consistent across states and age groups, with the greatest vasectomy uptake in men aged 35-44 years. Conclusion: Australia is undergoing a demographic shift characterised by rising vasectomy uptake and declining fertility. While vasectomy rates remain lower than birth rates, their convergence signals changing reproductive intentions and contraceptive behaviours. Ongoing monitoring of permanent and long-acting contraception is essential to understand evolving population dynamics and inform reproductive health policy.

Background: Hypertensive disorders of pregnancy contribute substantially to maternal morbidity and mortality, and occur with increased frequency among women with uterine fibroids. Biomarkers involved in oxidative stress and endothelial function, including folate, vitamin B12, vitamin D, and homocysteine, have been studied in relation to hypertensive disorders of pregnancy, but their relationship to fibroid-associated risk has not been well characterized, particularly in racially and ethnically diverse populations. Study Design: This study was a retrospective analysis of the Boston Birth Cohort, a prospective cohort recruited at a large urban medical center. The analytic sample included 722 women with complete data on hypertensive disorder status, uterine fibroid status, and plasma biomarker measurements. Uterine fibroids and hypertensive disorders of pregnancy were ascertained through physician-assigned diagnostic codes and ultrasound report review. Plasma folate, vitamin B12, vitamin D, and homocysteine were measured in maternal or cord blood and analyzed as continuous variables and quartiles. Multivariable logistic regression models were used to estimate independent associations, evaluate interaction terms, and assess joint exposure categories. Results: Of the 722 participants, 12% (86/722) had uterine fibroids and 10% (72/722) had a hypertensive disorder of pregnancy. Plasma micronutrient concentrations did not differ significantly by fibroid status. Women with hypertensive disorders of pregnancy had higher plasma homocysteine concentrations compared with those without (p=0.028). Hypertensive disorders of pregnancy were more common in the lowest folate quartile compared with the highest quartile (p=0.018) and in the highest homocysteine quartile compared with lower quartiles (p=0.031). In joint-effects analyses, higher odds of having a hypertensive disorder of pregnancy were observed among women with both uterine fibroids and low folate compared with women without fibroids and with adequate folate (p=0.027). No significant joint associations were observed for vitamin D, vitamin B12, or homocysteine. Conclusion: In this cohort, the co-occurrence of uterine fibroids and lower folate concentrations was associated with hypertensive disorders of pregnancy. This joint exposure delineates a subgroup that may be clinically relevant for future studies aimed at refining maternal risk characterization and exploring targeted nutritional supplementation strategies.

Objective: To address the need for improved measurement of the ways contraception impacts the baseline menstrual cycle (i.e., contraceptive-induced menstrual changes; CIMCs) by assembling an interdisciplinary, global research collective to rigorously develop a person-centered measure for CIMCs in multiple languages. As the first step, this paper reports on our conceptual model development, which is the foundation for ongoing measure development. Study design: We conducted 18 focus groups with 106 people experiencing CIMCs while using hormonal or intrauterine contraception in Durban, South Africa, Santo Domingo, Dominican Republic, and Portland Oregon, United States. We used a virtual affinity mapping approach to analyze qualitative data, which was the basis of our conceptual model along with relevant theory and related models in the literature. Results: The conceptual model of experiences with CIMCs depicts the baseline menstrual cycle, including CIMCs and conceptually-linked effects and the impacts and perceptions of those CIMCs. We found key domains of changes in pain, bleeding volume, bleeding patterns, and characteristics of blood. Conclusion: Our CIMC conceptual model will inform development of a measure with evidence of validation across three language and global contexts. Adoption of a person-centered, standardized CIMC measurement across trials will improve knowledge and decision-making between methods.