Oocyte aging is a key constraint on oocyte quality, leading to fertilization failure and abnormal embryonic development. In addition, it is likely to generate unfavorable assisted reproductive technology (ART) outcomes. SCM-198, a synthetic form of leonurine, was found to rescue the rate of oocyte fragmentation caused by postovulatory aging. Therefore, the aim of this study was to conduct a more in-depth investigation of SCM-198 by exploring its relationship with aged oocytes after ovulation or maternal aging and clarifying whether it affects cell quality. The results indicate that, compared to the postovulatory aged group, the 50 µM SCM-198 group significantly improved sperm-egg binding and increased fertilization of aged oocytes, restoring the spindle apparatus/chromosome structure, cortical granule distribution, and ovastacin and Juno protein distribution. The 50 µM SCM-198 group showed significantly normal mitochondrial distribution, low levels of reactive oxygen species (ROS), and a small quantity of early oocyte apoptosis compared to the postovulatory aged group. Above all, in vivo supplementation with SCM-198 effectively eliminated excess ROS and reduced the spindle/chromosome structural defects in aged mouse oocytes. In summary, these findings indicate that SCM-198 inhibits excessive oxidative stress in oocytes and alters oocyte quality both in vitro and in vivo.

Background and Objectives: Polycystic ovarian syndrome (PCOS) is a widespread endocrine disorder affecting 5-18% of females in their childbearing age. The aim of this study is to assess the efficacy of combining a low dosage of human chorionic gonadotropin (HCG) along with clomiphene citrate (CC) for stimulating ovulation in infertile women diagnosed with CC-resistant PCOS. Materials and Methods: A randomized controlled trial was carried out on 300 infertile CC-resistant PCOS women. All participants were assigned to two groups: the CC-HCG group and the CC-Placebo group. Subjects in the CC-HCG group were given CC (150 mg/day for 5 days starting on the 2nd day of the cycle) and HCG (200 IU/day SC starting on the 7th day of the cycle). Subjects in the CC-Placebo group were given CC and a placebo. The number of ovarian follicles > 18 mm, cycle cancellation rate, endometrial thickness, ovulation rate, clinical pregnancy rate, and occurrence of early ovarian hyper-stimulation syndrome were all outcome variables in the primary research. Results: Data from 138 individuals in the CC-HCG group and 131 participants in the CC-Placebo group were subjected to final analysis. In comparison to the CC-Placebo group, the cycle cancellation rate in the CC-HCG group was considerably lower. The CC-HCG group exhibited a substantial increase in ovarian follicles reaching > 18 mm, endometrial thickness, and ovulation rate. The clinical pregnancy rate was higher in the CC-HCG group (7.2% vs. 2.3%; CC-HCG vs. CC-Placebo). Upon adjusting for BMI and age, the findings of our study revealed that individuals in the CC-HCG group who had serum prolactin levels below 20 (ng/mL), secondary infertility, infertility duration less than 4 years, baseline LH/FSH ratios below 1.5, and serum AMH levels more than 4 (ng/mL) had a higher likelihood of achieving pregnancy. In the CC-Placebo group, there was a greater prediction of clinical pregnancy for those with serum AMH (<4), primary infertility, serum prolactin ≤ 20 (ng/mL), baseline LH/FSH < 1.5, and infertility duration < 4 years. Conclusions: The use of a small dose of HCG along with CC appeared to be an effective treatment in reducing cycle cancelation, improving the clinical pregnancy rate and ovulation rate in CC-resistant PCOS patients. The trial was registered with Clinical Trials.gov, identifier NCT02436226.

Background and Objectives: Fertility tracking apps and devices are now currently available, but urinary hormone levels lack accuracy and sensitivity in timing the start of the 6-day fertile window and the precise 24 h interval of transition from ovulation to the luteal phase. We hypothesized the serum hormones estradiol (E2) and progesterone (P) might be better biomarkers for these major ovulatory cycle events, using appropriate mathematical tools. Materials and Methods: Four women provided daily blood samples for serum E2, P, and LH (luteinizing hormone) levels throughout their entire ovulatory cycles, which were indexed to the first day of dominant follicle (DF) collapse (defined as Day 0) determined by transvaginal sonography; therefore, ovulation occurred in the 24 h interval of Day -1 (last day of maximum diameter DF) to Day 0. For comparison, a MiraTM fertility monitor was used to measure daily morning urinary LH (ULH), estrone-3-glucuronide (E3G), and pregnanediol-3-glucuronide (PDG) levels in three of these cycles. Results: There were more fluctuations in the MiraTM hormone levels compared to the serum levels. Previously described methods, the Fertility Indicator Equation (FIE) and Area Under the Curve (AUC) algorithm, were tested for identifying the start of the fertile window and the ovulation/luteal transition point using the day-specific hormone levels. The FIE with E2 levels predicted the start of the 6-day fertile window on Day -7 (two cycles) and Day -5 (two cycles), whereas no identifying signal was found with E3G. However, both pairs of (E2, P) and (E3G, PDG) levels with the AUC algorithm signaled the Day -1 to Day 0 ovulation/luteal transition interval in all cycles. Conclusions: serum E2 and (E2, P) were better biomarkers for signaling the start of the 6-day fertile window, but both MiraTM and serum hormone levels were successful in timing the [Day -1, Day 0] ovulatory/luteal transition interval. These results can presently be applied to urinary hormone monitors for fertility tracking and have implications for the direction of future fertility tracking technology.

Chronic stress has become a major problem that endangers people\'s physical and mental health. Studies have shown that chronic stress impairs female reproduction. However, the related mechanism is not fully understood. P2X7 receptor (P2X7R) is involved in a variety of pathological changes induced by chronic stress. Whether P2X7R is involved in the effect of chronic stress on female reproduction has not been studied. In this study, we established a chronic restraint stress mouse model and chronic cold stress mouse model. We found that the number of corpora lutea was significantly reduced in the two chronic stress models. The number of corpora lutea indirectly reflects the ovulation, suggesting that chronic stress influences ovulation. P2X7R expression was significantly increased in ovaries of the two chronic stress models. A superovulation experiment showed that P2X7R inhibitor A-438079 HCL partially rescued the ovulation rate of the two chronic stress models. Further studies showed that activation of P2X7R signaling inhibited the cumulus expansion and promoted the expression of NPPC in granulosa cells, one key negative factor of cumulus expansion. Moreover, sirius red staining showed that the ovarian fibrosis was increased in the two chronic stress models. For the fibrosis-related factors, TGF-β1 was increased and MMP2 was decreased. In vitro studies also showed that activation of P2X7R signaling upregulated the expression of TGF-β1 and downregulated the expression of MMP2 in granulosa cells. In conclusion, P2X7R expression was increased in the ovaries of the chronic restraint-stress and chronic cold-stress mouse models. Activation of P2X7R signaling promoted NPPC expression and cumulus expansion disorder, which contributed to the abnormal ovulation of the chronic stress model. Activation of P2X7R signaling is also associated with the ovarian fibrosis changes in the chronic stress model.

BACKGROUND: Study objectives included the development of a practical nomogram for predicting live birth following frozen-thawed embryo transfers in ovulatory women.
METHODS: Totally, 2884 patients with regular menstrual cycles in our center were retrospectively enrolled. In an 8:2 ratio, we randomly assigned patients to training and validation cohorts. Then we identified risk factors by multivariate logistic regression and constructed nomogram. Finally, receiver operating characteristic curve analysis, calibration curve and decision curve analysis were performed to assess the calibration and discriminative ability of the nomogram.
RESULTS: We identified five variables which were related to live birth, including age, anti-Müllerian hormone (AMH), protocol of frozen-thawed embryo transfer (FET), stage of embryos and amount of high-quality embryos. We then constructed nomograms that predict the probabilities of live birth by using those five parameters. Receiver operating characteristic curve analysis (ROC) showed that the area under the curve (AUC) for live birth was 0.666 (95% CI: 0.644-0.688) in the training cohort. The AUC in the subsequent validation cohorts was 0.669 (95% CI, 0.625-0.713). The clinical practicability of this nomogram was demonstrated through calibration curve analysis and decision curve analysis.
CONCLUSIONS: Our nomogram provides a visual and simple tool in predicting live birth in ovulatory women who received FET. It could also provide advice and guidance for physicians and patients on decision-making during the FET procedure.

The reproductive efficiency of the herd is correlated with higher productivity in livestock. Reproduction biotechniques, such as ovulation synchronization protocols, are important to optimize production and accelerate genetic profit in beef and dairy herds. The objective of this review is to describe the evolution over the last 40 years of the artificial insemination (AI) and the timed-AI (TAI) protocols in cattle from a Brazilian perspective. TAI protocols are based on synchronizing emergence of the wave of follicular growth, controlling circulating progesterone (P4) concentrations, stimulating the final growth of the follicle and inducing a synchronized ovulation. Hormonal alternatives that optimize the response at the end of the protocol and strategies to induce final follicle growth and ovulation in categories of females with low expression of estrus are described. Furthermore, the potential positive effect of previous exposure to injectable P4 on fertility of Bos indicus and Bos taurus cows is also discussed.

BACKGROUND: Accurately predicting ovulation timing is critical for women undergoing natural cycle-frozen embryo transfer. However, the precise predicting of the ovulation timing remains challenging due to the lack of consensus among different clinics regarding the definition of this significant event.
OBJECTIVE: To compare the effectiveness of preovulatory serum progesterone levels (P4) versus luteinizing hormone levels (LH) in predicting ovulation time using two machine learning models.
METHODS: 771 patients who underwent autologous natural cycle-frozen embryo transfer between January 2015 and February 2022 were recruited. Utilizing variables including follicle diameters, preovulatory serum levels of LH, E2, and P4, two machine learning models were constructed to predict the ovulation time, the importance of the variables in predicting ovulation timing was further ranked.
RESULTS: Two machine learning models have the capability to accurately predict the timing of ovulation, specifically within 72, 48, or 24 h. The overall accuracy rates of the validation dataset, as determined by the classification trees and random forest models, were found to be 78.83% and 85.28% respectively. Notably, when predicting ovulation within 24 h, the accuracy rate of P4 ≥ 0.65ng/ml exceeded 92%. Furthermore, it was important to consider LH or E2 levels in conjunction with P4 when assessing ovulation timing in cases where P4<0.65ng/ml.
CONCLUSIONS: Preovulatory serum P4 levels are better predictors of ovulation timing than LH levels and could be used as an alternative in clinical settings, and the model we developed can be used to pinpoint the day of ovulation. Ongoing research and advancements in technology are anticipated to enhance and refine the ovulation method.

UNASSIGNED: Endometriosis is a chronic inflammatory disease of women during their reproductive years. The relationship between the severity and location of endometriosis and menstruation, ovulation, reproductive function, and mode of delivery remains unclear.
UNASSIGNED: We explored the association between the various phenotypes of endometriosis and menstruation, ovulation, reproductive function, and mode of delivery, using two-sample Mendelian randomization (MR) and summary data on endometriosis stages and locations from the FinnGen consortium and women\'s menstruation, ovulation, reproductive function, and mode of delivery from OpenGWAS and ReproGen. Inverse-variance weighting was used for the primary MR analysis. In addition, a series of sensitivity analyses, confounding analyses, co-localization analyses, and multivariate MR analyses were performed.
UNASSIGNED: MR analysis showed a negative effect of moderate to severe endometriosis on age at last live birth (OR = 0.973, 95% CI: 0.960-0.986) and normal delivery (OR = 0.999, 95% CI: 0.998-1.000; values for endpoint were excluded), ovarian endometriosis on age at last live birth (OR = 0.976, 95% CI: 0.965-0.988) and normal delivery (OR = 0.999, 95% CI: 0.998-1.000; values for endpoint were excluded), and fallopian tubal endometriosis on excessive irregular menstruation (OR = 0.966, 95% CI: 0.942-0.990). Bidirectional MR analysis showed that age at menarche had a negative causal effect on intestinal endometriosis (OR = 0.417, 95% CI: 0.216-0.804). All MR analyses were confirmed by sensitivity analyses, and only the genetic effects of moderate to severe endometriosis on normal delivery and age at last live birth were supported by co-localization evidence.
UNASSIGNED: Our findings deepen the understanding of the relationship between various types of endometriosis and menstruation, ovulation, reproductive function, and mode of delivery and clarify the important role of moderate to severe endometriosis.

Aminergic nuclei in mammals are generally composed of relatively small numbers of cells with broad projection patterns. Despite the gross similarity of many individual neurons, recent transcriptomic, anatomic and behavioral studies suggest previously unsuspected diversity. Smaller clusters of aminergic neurons in the model organism Drosophila melanogaster provide an opportunity to explore the ramifications of neuronal diversity at the level of individual cells. A group of approximately 10 tyraminergic/octopaminergic neurons innervates the female reproductive tract in flies and has been proposed to regulate multiple activities required for fertility. The projection patterns of individual neurons within the cluster are not known and it remains unclear whether they are functionally heterogenous. Using a single cell labeling technique, we show that each region of the reproductive tract is innervated by a distinct subset of tyraminergic/octopaminergic cells. Optogenetic activation of one subset stimulates oviduct contractions, indicating that the cluster as a whole is not required for this activity, and underscoring the potential for functional diversity across individual cells. Using whole cell patch clamp, we show that two adjacent and morphologically similar cells are tonically inhibited, but each responds differently to injection of current or activation of the inhibitory GluCl receptor. GluCl appears to be expressed at relatively low levels in tyraminergic/octopaminergic neurons within the cluster, suggesting that it may regulate their excitability via indirect pathways. Together, our data indicate that specific tyraminergic/octopaminergic cells within a relatively homogenous cluster have heterogenous properties and provide a platform for further studies to determine the function of each cell.

The mechanisms behind the selection and initial recruitment of primordial follicles (PmFs) from the non-growing PmF pool during each estrous cycle in females remain largely unknown. This study demonstrates that PmFs closest to the ovulatory follicle are preferentially activated in mouse ovaries under physiological conditions. PmFs located within 40 μm of the ovulatory follicles were more likely to be activated compared to those situated further away during the peri-ovulation period. Repeated superovulation treatments accelerated the depletion of the PmF reserve, whereas continuous suppression of ovulation delayed PmF reserve consumption. Spatial transcriptome sequencing of peri-ovulatory follicles revealed that ovulation primarily induces the degradation and remodeling of the extracellular matrix (ECM). This ECM degradation reduces mechanical stress around PmFs, thereby triggering their activation. Specifically, Cathepsin L (CTSL), a cysteine proteinase and lysosomal enzyme involved in ECM degradation, initiates the activation of PmFs adjacent to ovulatory follicles in a distance-dependent manner. These findings highlight the link between ovulation and selective PmF activation, and underscore the role of CTSL in this process under physiological conditions.