Natural versus GnRHa-HRT cycle for FET in tubal infertility with prior failed natural cycles: a propensity score-matched retrospective cohort study.

The optimal endometrial preparation protocol for frozen embryo transfer (FET) remains a subject of ongoing investigation. HRT is the most commonly used approach, but natural cycle (NC) FET has regained attention due to potential improvements in maternal and perinatal outcomes. Despite growing observational evidence supporting NC FET, its adoption is limited by logistical challenges in cycle monitoring and scheduling. Recently, the natural proliferative phase (NPP) FET protocol has been introduced, combining the physiological benefits of a functional corpus luteum with greater scheduling flexibility. Previous systematic reviews have largely focused on luteal phase support (LPS) or have provided narrative summaries susceptible to selection bias. This systematic review aimed to evaluate the impact of different execution strategies on reproductive outcomes across true-NC and modified-NC and to compare NPP FET with other protocols. A comprehensive search of MEDLINE, Embase, Global Health, and Cochrane Library was conducted from database inception to 10 November 2024. The search included keywords such as 'frozen embryo transfer', 'natural cycle', 'pregnancy', 'live birth', and 'delivery' with no language or filter restrictions. Reference lists of included studies were screened to identify additional relevant studies. A total of 70 studies were included: 8 randomized controlled trials (1 with low risk of bias and 7 with some concerns), 16 non-randomized interventional studies (with risk of bias being moderate for 4, serious for 6, and critical for another 6), and 46 observational studies (80.4% of which were good quality) assessing prognostic factors. In true-NC FET, prolonged follicular phases did not adversely affect outcomes. Ovulatory cycles were associated with significantly higher live birth rates (LBRs) than cycles with luteinized unruptured follicle (risk ratio (RR): 1.16, 95% CI: 1.04-1.29, I2 = 0%, three studies, 2907 cycles, very low-certainty evidence). Despite variability in ovulation timing methods, performing FET on serum LH surge +6 to +7 days yielded comparable reproductive outcomes. In modified-NC FET, two observational studies reported similar LBRs when triggering ovulation at follicle diameters between 13 and 22 mm, provided the endometrial thickness was >7 mm and serum progesterone was below 1.5 ng/ml. LPS with vaginal progesterone improved LBRs in true-NC compared to no LPS (RR: 1.43, 95% CI: 1.16-1.78, I2 = 0%, 923 cycles, two studies, moderate-certainty evidence), but showed no benefit in modified-NC FET (RR: 1.04, 95% CI: 0.82-1.32, I2 = 0%, 667 cycles, two studies, moderate-certainty evidence). In NPP FET, a meta-analysis showed higher LBRs compared to HRT FET (RR: 1.25, 95% CI: 1.13-1.38, I2 = 5.36%, 3397 cycles, three studies, very low-certainty evidence). NC FET protocols are associated with operational constraints. Modified-NC and NPP strategies may balance physiological benefits with scheduling convenience, though high-quality evidence remains limited. Routine LPS improves LBRs in true-NC FET but not in modified-NC. The apparent equivalence of outcomes when hCG is administered across a follicle size range of 13-22 mm suggests a potential 7-day window of scheduling flexibility for modified-NC FET; however, this finding warrants further validation. NPP FET may offer enhanced scheduling convenience without compromising reproductive outcomes, but warrants additional investigation through high-quality trials. PROSPERO: CRD42023385304.

Sex - and its associated gonadal hormones - matters for binge eating (BE). On average, females report higher BE than males. Estradiol generally suppresses appetite, whereas progesterone opposes estradiol's action such that their combined presence represents a high-risk hormonal milieu for BE. Testosterone is thought to be associated with increased BE in females but appears protective in males. Hormonal contraceptives (HCs) provide a naturalistic means to study the relation between gonadal hormones and BE, as HCs vary in formulations and delivery. Oral contraceptive (OC) use has been linked to greater BE-related appetitive processes (e.g., food intake); however, the association with BE itself has not been studied, and research has overlooked hormonal variation across OCs. No study has systematically examined BE and hormonal intrauterine devices (IUDs), which differ in formulation and delivery from other HCs. We explored hormone-BE links in 401 human females (181 naturally cycling (NC); 152 OC users; 53 IUD users) and 159 males aged 18-44 years. ANCOVA tested differences in Binge Eating Scale (BES) summary scores across sex and HC groups (NC, OC, and IUD). Hierarchical linear regressions examined relations between OC hormone activities and BES summary scores. Analyses controlled for BMI and age. In this sample, females reported higher BE than males, but BE did not differ across HC groups or vary with OC hormonal activities. Null results may reflect true group-level similarities in BE or individual differences in vulnerability to hormonal exposures. Further research should replicate and extend these findings to other samples and using other methodologies.

Emerging evidence suggests that G-protein-coupled receptor family C group 6 member A (GPRC6A) and Dual oxidase 1 (Duox1) mediate a non-classical testosterone signaling pathway. However, the molecular mechanism in which testosterone mediates the GPRC6A-Duox1 cascade in the hair cycle was unclear. Therefore, this study aimed to elucidate the molecular role of the testosterone-GPRC6A-Duox1 signaling axis in regulating hair cycle progression and testosterone-mediated hair loss. GPRC6A-deficient and Duox1-deficient keratinocytes were prepared and stimulated with testosterone to assess hydrogen peroxide (H2O2) generation. Apoptosis was evaluated in primary keratinocytes from GPRC6A knockout (KO), Duox1 KO, and wild-type (WT) mice. Hair growth cycle progression was examined by measuring anagen phase duration and hair length. Ki-67 expression was analyzed as a marker of the anagen phase. To validate the testosterone-GPRC6A-Duox1 signaling network in androgenetic alopecia, testosterone was topically applied for one week to the back skin of WT, Duox1 KO, and GPRC6A KO mice on postnatal day 31 (P31). GPRC6A-deficient and Duox1-deficient keratinocytes failed to induce H2O2 generation in response to testosterone. Testosterone-dependent apoptosis in primary keratinocytes from GPRC6A KO and Duox1 KO mice was suppressed compared to keratinocytes from WT. The anagen phase of the hair growth cycle and hair lengths in GPRC6A KO and Duox1 KO mice were longer than WT consistent with the GPRC6A-Duox1 axis stimulating the anagen-to-catagen transition. The expression of Ki-67, a hallmark of the anagen phase, in GPRC6A KO and Duox1 KO mice was higher than that in WT. Duox1 KO and GPRC6A KO mice were resistant to testosterone-mediated hair loss, unlike WT. Taken together, these results suggest that the GPRC6A-Duox1 axis regulates natural hair cycles and testosterone-mediated hair loss.

Plant-inspired sustainable hydrokinetic electricity generation through natural evapotranspiration cycle

Light pollution by coastal streetlights affects intertidal grazers and biofilm differentially in natural rocky habitats and breakwaters.

Arboviruses represent a persistent and escalating threat to global public health, with mosquitoes serving as the principal vectors in their natural transmission cycles and geographic dissemination. Yunnan Province, southwestern China, is a recognized hotspot for arboviral diversity, yet the full spectrum of mosquito-borne viruses circulating in this region remains incompletely characterized. A total of 3,300 female mosquitoes of four species across four genera were collected from rural areas of Honghe County, Yunnan Province in 2024, and subjected to viral metatranscriptomic sequencing. A previously undescribed bunya-like virus, designated Honghe Bunya-like virus, was identified in two locally dominant hematophagous mosquito species, with minimum infection rates of 0.2% and 0.3%, respectively. The viral genome comprises three single-stranded negative-sense RNA segments (L, M, and S) encoding the RdRp, glycoprotein, and nucleoprotein, respectively, consistent with the canonical architecture of the genus Orthobunyavirus. Phylogenetic analyses placed the virus within Orthobunyavirus across all three segments, though inter-segment topological incongruence was observed; amino acid identities to known orthobunyaviruses (49.7%-71.6%) fell below conspecific thresholds, suggesting a novel species. This study expands the known genetic diversity of mosquito-associated virus in southwestern China and, given the phylogenetic affinity to pathogenic orthobunyaviruses and the hematophagous nature of the vector species, raises the possibility of vertebrate infection potential warranting further investigation.

Water evaporation, a physical process effectively driving natural hydrological cycles, has long suffered from rate limitations in industrial applications. Particularly in scenarios such as solar steam generation and evaporation cooling, the evaporation rate of conventional evaporators struggles to meet the practical request, due to the unresolved boundary layer resistance at the liquid-air interface. Here, we reinvent Nikola Tesla's fluidic diode into a reverse Tesla valve modulated bulk-effect evaporation system (BEES). By leveraging structure-induced vortex airflow to disrupt thermal and mass transfer boundary layers, BEES unlocks previously unattainable evaporation dynamics at the inner liquid-air interface and achieves an evaporation rate of 21.29 kg m-2 h-1, with a total energy/solar efficiency of 627%. Our BEES enables all-day freshwater harvesting and efficient evaporative cooling, achieving energy savings of 414 GJ m-3 month-1. This work establishes a bulk-effect evaporation framework complementary to traditional interfacial engineering for addressing the water-energy nexus.

Placental pathology and weight following Intrauterine Insemination (IUI) with or without ovarian stimulation (OS).

In modern society, due to rapid urbanization and industry growth, different types of pollutants are accumulating in the environment and making it polluted. The excessive discharge of organic toxins into water bodies is a major contributor to environmental pollution and poses significant health risks to society and the environment. Organic toxins from various chemical and textile industries pollute our water resources, forming breeding centers for different disease pathogens and adversely affecting the natural water cycle. Therefore, to protect and sustain life on the planet, it should be our prime mandate to preserve, manage, and remediate our limited available water resources. Organic pollutant decomposition is a difficult task due to their complex nature; therefore, it is important to understand the structures of different pollutants to decompose them perfectly. This review highlights the classification of various pollutants, their structural properties, and their possible detoxification processes through the advanced photocatalytic processes. In addition, the elaboration for the decomposition mechanism of the different toxins, ranging from azo dyes, phenols, pesticides, and nitrogen-based compounds to halo-compounds, has been explained. This review also briefly explains the underlying charge transfer mechanism used by different photocatalysts, such as metal oxide semiconductors and 2D-layered nanostructures. A brief description of this mechanism is mentioned in the review, along with the fundamental principle, the role of active redox radicals, such as superoxides and hydroxyl ions, in facilitating the photocatalytic degradation process. Lastly, the creation of robust and scalable photocatalytic systems for practical environmental applications is discussed along with the knowledge gaps and future research goals. This review provides invaluable insight into developing the advanced photocatalyst materials for the targeted pollutants.

In vitro fertilization (IVF) culminates in embryo transfer into a hormonally primed endometrium, often via a programmed cycle (PC) regimen postulated to influence hypertensive disorders of pregnancy (HDP) risk. We thus generated a single-cell atlas of PC endometrium to define cell type-specific differences relative to natural cycle (NC) endometrium, and evaluated whether PC-associated modulation of the window of implantation (WOI) endometrium influences angiogenic balance in pregnancy. Single-nucleus RNA-seq of prospectively collected PC and NC WOI endometrium. An independent prospective cohort of 548 singleton pregnancies was separately analyzed for maternal serum angiogenic markers (soluble fms-like tyrosine kinase-1; placental growth factor) and HDP incidence in PC- versus NC-conceived pregnancies, adjusting for clinical confounders and IVF use. Prominent transcriptomic differences were observed between PC (n = 7; 48,843 nuclei) and NC (n = 9; 44,230 nuclei) WOI endometrium, particularly in glandular epithelium (682 up- and 979 down-regulated genes; adjusted P < 0.05) and stromal fibroblasts (108 up- and 168 down-regulated). PC endometrium showed reduced uterine natural killer cell abundance, potentially from CXCL14 downregulation. Functional enrichment revealed downregulation of embryo implantation, angiogenesis, and extracellular matrix remodeling pathways in PC. Altered cell-cell signaling in decidualization, angiogenesis, and inflammatory response was also observed. Despite these WOI perturbations, PC-conceived pregnancies were not associated with early gestational angiogenic imbalance or increased HDP risk. PC endometrial preparation induced distinct cellular and signaling alterations in the WOI, but was not associated with subsequent development of angiogenic imbalance or HDP, thereby underscoring the resilience and adaptability of the early maternal-fetal interface. gov NCT03799107. ABOG/AAOGF; NICHD-R01-HD084380; NCTRI-P50-HD055764; NIAMS-P30-AR070155.

Does a natural cycle result in higher clinical pregnancy rates (CPR) with foetal heartbeat compared to an artificial cycle for frozen-thawed embryo transfer (FET) preparation in ovulatory women? The CPR with foetal heartbeat did not differ between natural and artificial cycles in ovulatory women undergoing FET. Several protocols for endometrial preparation have been developed for the increasing number of FET cycles in reproductive medicine. In natural cycle FET (NC-FET), spontaneous ovulation is used to time the embryo thawing and transfer, while in artificial cycle FET (AC-FET), endometrial preparation involves sequential oestrogen and progesterone administration. Current evidence on pregnancy rates does not favour one regimen over the other in women with regular ovulatory cycles. We conducted a multicentre, open-label, randomised trial comparing NC-FET with AC-FET across five Belgian fertility centres. Between October 2018 and October 2024, 561 women were randomised (1:1) using a computer-generated allocation after written informed consent. The primary outcome was CPR with foetal heartbeat per cycle analysed on an intention-to-treat basis. Secondary outcomes included endometrial thickness, number of clinic visits for FET cycle monitoring and the rates of (biochemical) pregnancy, ongoing pregnancy, live birth, miscarriage, ectopic pregnancy, multiple pregnancy and cycle cancellation. Obstetric outcomes were recorded for all ongoing pregnancies. Women aged 18-45 with regular ovulatory cycles and normal uterine cavities undergoing FET after vitrification and warming of one or two day-3 embryos or blastocysts were included. In NC-FET, spontaneous ovulation was detected by serial ultrasounds and serum LH and oestradiol measurements. In AC-FET, oestradiol valerate (6 mg/day) was administered from cycle day 2 (increased to 8 mg/day after 1 week if endometrial thickness was <7 mm) and micronized progesterone (600 mg/day) was initiated once endometrial thickness reached ≥7 mm. Clinical pregnancy rates with foetal heartbeat were similar between NC-FET and AC-FET in both intention-to-treat (33.1% [94/284] vs 28.9% [80/277]; RR 1.15, 95% CI 0.89, 1.47) and as-treated analyses (34.3% [97/283] vs 31.8% [77/242]; RR 1.08, 95% CI 0.85, 1.38). Cycle cancellations were less frequent in NC-FET (3.9% vs 9.4%; RR 0.41, 95% CI 0.21, 0.82), but NC-FET required more monitoring visits (mean 3.0 vs 2.4; P = 0.0002). Caesarean section was more common after AC-FET (42.7% vs 20.2%; P = 0.003). Other reproductive, obstetric, and perinatal outcomes did not differ significantly between groups. The sample size was powered to detect a difference in CPR with foetal heartbeat, not for comparing live birth rates or obstetric outcomes. The study was performed in ovulatory women undergoing FET, and therefore, results may not be applicable to other populations. This RCT demonstrates no significant difference in CPR with foetal heartbeat in NC-FET and AC-FET in ovulatory women. Given recent data suggesting higher obstetric risks with AC-FET, NC-FET may be preferred in women with normal ovulatory cycles. The study was an investigator-initiated study supported by internal KU Leuven funding (Project number C14/18/106 and C14/24/152) and funding from the Research Foundation Flanders (G.084515N and G.0B1819N to J.V.). K.P. has received grants from Ferring. C.B. has received speaker fees from Gedeon Richter, paid to her institution; travel support from Gedeon Richter, Ferring Pharmaceuticals, and Intuitive; and holds a leadership role as Senior Deputy of the ESHRE SIG Endometriosis and Endometrial Disorders. C.T. has received grants from Merck SA, paid to her institution; consulting fees and speaker fees from Gedeon Richter; travel support from Ferring and Gedeon Richter; and holds leadership roles as Deputy Editor of JNIG and as a board member. A.V. has received speaker fees from Gedeon Richter, paid to his institution, and holds a leadership role as Senior Deputy of the ESHRE SIG Endometriosis and Endometrial Disorders. The other authors declare that there is no conflict of interest to disclose with respect to the content of this article. This trial has been registered at ClinicalTrials.gov (NCT03642665). 17 July 2018. 27 October 2018.

Redox homeostasis in human follicular fluid: A comparison of modified natural cycle and controlled ovarian stimulation in idiopathic infertility.

To evaluate whether the timing of luteal phase support (LPS) initiation affects pregnancy outcomes in natural cycle vitrified-warmed blastocyst transfer (NC-FET) cycles. This retrospective cohort study included NC-FET cycles performed between January 2022 and December 2024 at a tertiary university fertility center. Only true natural cycles with blastocyst transfer were analyzed. Patients were divided into two groups according to the initiation of LPS: two days before embryo transfer (Group 1) or on the day of embryo transfer (Group 2). All patients received vaginal and subcutaneous progesterone for LPS. Baseline characteristics, embryo features, serum progesterone levels on transfer day, and reproductive outcomes were compared. Multivariate logistic regression and receiver operating characteristic (ROC) analyses were performed to identify factors associated with clinical pregnancy. A total of 246 NC-FET cycles were analyzed (Group 1: n = 172; Group 2: n = 74). Baseline characteristics, embryo quality, and transfer parameters were comparable between groups. Serum progesterone levels on the day of transfer were significantly higher in Group 1 (32.1 ± 13.0 ng/mL) compared with Group 2 (10.3 ± 3.8 ng/mL; p = 0.001). However, total pregnancy rate (66.2% vs. 47.1%, p = 0.006), clinical pregnancy rate (56.8% vs. 40.7%, p = 0.020), and live birth rate (52.7% vs. 37.2%, p = 0.024) were significantly higher in Group 2. Logistic regression analysis showed that initiation of LPS on the day of transfer was independently associated with increased clinical pregnancy (OR 2.37, 95% CI 1.17-4.81). Serum progesterone level did not predict pregnancy outcomes. In NC-FET cycles, initiating luteal phase support on the day of embryo transfer is associated with improved pregnancy and live birth rates compared with earlier initiation, despite lower serum progesterone levels.

Purpose To inform contraceptive decisions, we aimed to compare the pregnancy and continuation rates of a digital contraceptive, when paired with temperature data from wearable devices versus from oral thermometers. Materials and methods We employed prospectively collected data from women who registered to Natural Cycles for contraception between the 1st of August 2022 and the 1st of September 2024. Using Kaplan-Meier curves, we calculated 13-cycle pregnancy rates in typical and perfect use as well as one-year continuation rates. We estimated the association of known demographic characteristics with pregnancy rates using a multivariate Cox proportional hazards model. Results Among the 195 027 presumed fertile women whom we analysed, the unadjusted 13-cycle pregnancy rate for wearable device users was significantly lower than for oral thermometer users both in typical use (4.7% vs 7.3%; p < 0.001) and in perfect use (2.0% vs 2.9%; p < 0.001). However, when adjusting for demographics, measuring with a wearable device rather than a thermometer was not independently associated with pregnancy. We observed one-year continuation rates of 75.8% for wearable device users and 56.4% for thermometer users. Conclusions Findings from this study suggest that combining a contraceptive app with a wearable device rather than an oral thermometer does not affect pregnancy rates when adjusting for socio-demographic variables. However, the substantial increase in continuation implies greater user convenience.

Despite notable differences in cancer incidence and outcomes, fewer American Indians have participated in cancer research and genomic testing relative to their population size. Contributing factors include historical scientific mistrust, lack of culturally appropriate research methodologies, and limited access. With the launch of a cancer genomic sequencing trial in American Indians from the Southwestern United States (US), clinicians and staff encountered challenges engaging patients, recognizing the complexity of research in this population. We describe a novel approach to educate study team members regarding genomic cancer testing and research in American Indian populations. Clinical faculty and staff investigators participated in (1) hands-on experiential workshops related to core beliefs and healthcare in American Indians and (2) the development of provider-facing educational materials. After participation in the workshops, investigators, including American Indian researchers, created two sets of provider-facing materials and implemented them in clinic. The first provided a summary detailing trial eligibility, procedures, and privacy safeguards. The second outlined topics fostering respectful engagement of American Indians in research, outlining core beliefs including the importance of family and community in decisions, a framework of inherent cycles in human life and nature, the importance of visual aids, and the complementary nature of traditional healing. An approach incorporating cultural training for clinicians and staff is feasible when engaging American Indians of the Southwestern US in genomic research. This methodology may serve as a model for future initiatives to engage with American Indians in cancer research and in both clinical and research related genomic testing.

To compare live-birth rates between natural cycle and artificial cycle endometrial preparation protocols in women undergoing frozen embryo transfer. A comprehensive literature search was conducted through July 2025 across PubMed, EMBASE, Cochrane Library, ClinicalKey, ProQuest, Cumulative Index to Nursing and Allied Health Literature Plus, ClinicalTrials.gov, and World Health Organization International Clinical Trials Registry Platform. Search terms combined "frozen embryo transfer," "endometrial preparation," "natural cycle," and "artificial cycle" with no language restrictions during search phase. Only randomized controlled trials comparing natural cycle with artificial cycle preparation in women aged 18-45 years undergoing frozen embryo transfer were included. Studies were required to report live-birth rate or clinical pregnancy rate. Of 824 records identified, 45 full-text articles were assessed, and 11 randomized controlled trials (9,955 women) met inclusion criteria. Review Manager 5.4 was used for meta-analyses. Data were extracted independently by two reviewers using standardized forms. Risk of bias was assessed with the Cochrane Risk of Bias Tool 2.0. Natural cycle preparation demonstrated significantly higher live-birth rates (41.5% vs 39.2%; risk ratio [RR] 1.11, 95% CI, 1.03-1.19, P=.007; moderate-quality evidence), corresponding to 43 more live births per 1,000 women and a number needed to treat of 23. Modified natural cycle showed significant benefit (RR 1.11, 95% CI, 1.01-1.23, P=.03), whereas true natural cycle showed no significant difference (RR 1.08, 95% CI, 0.95-1.23, P=.21). Natural cycle was associated with lower miscarriage rates (13.4% vs 17.5%; RR 0.76, 95% CI, 0.67-0.87, P<.001; moderate-quality evidence). Natural cycle endometrial preparation, particularly modified natural cycle with human chorionic gonadotropin trigger, is associated with higher live-birth rates compared with artificial cycle preparation, although true natural cycle showed no significant difference. PROSPERO, CRD420251090016.

Environmental pollution resulting from the rapid increase in human population, urbanization, intensive use of chemicals in agriculture, and industrial development has reached a level that threatens natural life today. Trace elements are one of the most important factors causing significant levels of pollution in the environment and are added to marine ecosystems in high concentrations because of both natural cycles and non-cycle factors. While essential metals show functional properties by entering the structural composition of living organisms at low concentrations, it is known that non-essential metals do not have any biological function. Deficiency or high concentrations of metals, which are required in trace amounts by living organisms for vital events, and the effect of toxic metals at low concentrations cause disturbances in metabolic and physiological events, accumulation in tissues and organs, and are transported to higher trophic levels at increasing values through the food chain, ultimately causing significant environmental and health problems. The aim of this study was to determine the concentrations of Al, Cr, Mn, Fe Co, Ni, Cu, Zn, As, Cd, Hg, and Pb in the muscle tissues of Squalus acanthias, Raja clavata, and Dasyatis pastinaca from the southern Black Sea. By focusing on these non-commercial but ecologically important top predators, the study contributes to the assessment of ecological risks and management strategies for the region.

Views and Reviews: Therapeutic Donor Insemination.

Satellites reveal contrasting seasonal buffering patterns of global lakes and reservoirs.