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17,215 result(s) for "Fertility - physiology"
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Wearable Sensors Reveal Menses-Driven Changes in Physiology and Enable Prediction of the Fertile Window: Observational Study
Previous research examining physiological changes across the menstrual cycle has considered biological responses to shifting hormones in isolation. Clinical studies, for example, have shown that women's nightly basal body temperature increases from 0.28 to 0.56 ˚C following postovulation progesterone production. Women's resting pulse rate, respiratory rate, and heart rate variability (HRV) are similarly elevated in the luteal phase, whereas skin perfusion decreases significantly following the fertile window's closing. Past research probed only 1 or 2 of these physiological features in a given study, requiring participants to come to a laboratory or hospital clinic multiple times throughout their cycle. Although initially designed for recreational purposes, wearable technology could enable more ambulatory studies of physiological changes across the menstrual cycle. Early research suggests that wearables can detect phase-based shifts in pulse rate and wrist skin temperature (WST). To date, previous work has studied these features separately, with the ability of wearables to accurately pinpoint the fertile window using multiple physiological parameters simultaneously yet unknown. In this study, we probed what phase-based differences a wearable bracelet could detect in users' WST, heart rate, HRV, respiratory rate, and skin perfusion. Drawing on insight from artificial intelligence and machine learning, we then sought to develop an algorithm that could identify the fertile window in real time. We conducted a prospective longitudinal study, recruiting 237 conception-seeking Swiss women. Participants wore the Ava bracelet (Ava AG) nightly while sleeping for up to a year or until they became pregnant. In addition to syncing the device to the corresponding smartphone app daily, women also completed an electronic diary about their activities in the past 24 hours. Finally, women took a urinary luteinizing hormone test at several points in a given cycle to determine the close of the fertile window. We assessed phase-based changes in physiological parameters using cross-classified mixed-effects models with random intercepts and random slopes. We then trained a machine learning algorithm to recognize the fertile window. We have demonstrated that wearable technology can detect significant, concurrent phase-based shifts in WST, heart rate, and respiratory rate (all P<.001). HRV and skin perfusion similarly varied across the menstrual cycle (all P<.05), although these effects only trended toward significance following a Bonferroni correction to maintain a family-wise alpha level. Our findings were robust to daily, individual, and cycle-level covariates. Furthermore, we developed a machine learning algorithm that can detect the fertile window with 90% accuracy (95% CI 0.89 to 0.92). Our contributions highlight the impact of artificial intelligence and machine learning's integration into health care. By monitoring numerous physiological parameters simultaneously, wearable technology uniquely improves upon retrospective methods for fertility awareness and enables the first real-time predictive model of ovulation.
Ovarian reserve in patients with ankylosing spondylitis
Purpose The aim of this study was to determine the autoimmune effects of ankylosing spondylitis (AS) on the fertility potential of women by evaluating ovarian reserves of AS patients. Methods A total of 104 patients, 52 in the AS group (study group) and 52 in the control group were included in the study. Ovarian reserve was evaluated by serum anti-Müllerian hormone (AMH) levels, antral follicle count (AFC) and baseline serum follicle-stimulating hormone (FSH) levels. Results The mean serum AMH levels were significantly lower in the study group when compared to the controls (2.203 ± 1.110 vs. 1.188 ± 0.891, p  < 0.001). In addition, the mean AFC was also significantly lower in the study group. (10.67 ± 1.81 vs. 9.54 ± 2.50, p  = 0.009). Mean FSH levels were calculated to be 6.72 ± 1.14 in the study group and 7.21 ± 1.22 in the control group. The difference was not statistically significant ( p  = 0.781). Conclusion This study shows that AS like several other autoimmune conditions has an adverse effect on the female fertility potential. Therefore, an early start and long-term management of AS patients who have fertility desire is recommended. Serum AMH levels can be used in monitoring ovarian reserve and in early detection of reproductive decline of AS patients. ClinicalTrial Number NCT04209881.
An intervention in contraceptive counseling increased the knowledge about fertility and awareness of preconception health-a randomized controlled trial
Background: Reproductive life plan counseling (RLPC) is a tool to encourage women and men to reflect upon their reproduction, to avoid unintended pregnancies and negative health behavior that can threaten reproduction. The aim was to evaluate the effect of RLPC among women attending contraceptive counseling. Outcomes were knowledge about fertility and awareness of preconception health, use of contraception, and women's experience of RLPC. Material and methods: Swedish-speaking women, aged 20-40 years, were randomized to intervention group (IG) or control group (CG). Participants (n = 1,946) answered a questionnaire before and two months after (n = 1,198, 62%) the consultation. All women received standard contraceptive counseling, and the IG also received the RLPC, i.e. questions on reproductive intentions, information about fertility, and preconception health. Results: Women in the IG increased their knowledge about fertility: age and fertility, chances of getting pregnant, fecundity of an ovum, and chances of having a child with help of IVF. They also increased their awareness of factors affecting preconception health, such as to stop using tobacco, to refrain from alcohol, to be of normal weight, and to start with folic acid before a pregnancy. The most commonly used contraceptive method was combined oral contraceptives, followed by long-acting reversible contraception. Three out of four women (76%) in the IG stated that the RLPC should be part of the routine in contraceptive counseling. Conclusions: Knowledge about fertility and awareness of preconception health increased after the intervention. The RLPC can be recommended as a tool in contraceptive counseling.
Comparing the Effectiveness of Dietary Vitamin C and Exercise Interventions on Fertility Parameters in Normal Obese Men
Comparing the effectiveness of dietary vitamin C and weight loss exercises interventions for weight loss on semen characteristics in normal obese man. A total number of 200 men were randomly allocated into two groups based on body mass index, exercise and vitamin C groups. Also, 50 men with normal spermogram were placed in a control group. In exercise group, a 6 months intensive exercise program was designed under a coach's supervision to reduce the body weight. In vitamin C group, 1,000 mg of vitamin C were given every other day as supplement. Weight loss increased the volume of semen in participants with 25-30 (P = .02) and more than 30 body mass index (P = .001). The increased concentration of sperm per mL of semen in body mass index (BMI) 25-30 group (P = .01) and more than 30 (P = .003) BMI was significant. Improving sperm motility after two hours in participants with more than 30 (P = .01) BMI was significant. In vitamin C group, the improvement of sperm concentration in participants who had less than 25 (P = .01), between 25 and 30 (P = .01), more than 30 (P = .02) BMI was significant. Sperm motility improved in all three groups (P = .001, P = .02 and P = .003, respectively). Weight loss can significantly increase semen volume, its concentration, its mobility and percentage of normal morphology. Consuming vitamin C significantly improves sperm concentration and mobility, but the semen volume and the percentage of normal morphology will not change significantly.
Anti-Müllerian Hormone and Ovarian Reserve: Update on Assessing Ovarian Function
Abstract Context Anti-müllerian hormone (AMH) is produced by granulosa cells of small, growing follicles in the ovary. Serum AMH levels strongly correlate with the number of growing follicles, and therefore AMH has received increasing attention as a marker for ovarian reserve. This review summarizes recent findings and limitations in the application of serum AMH in ovarian reserve assessment. Evidence Acquisition A PubMed search was conducted to find recent literature on the measurements and use of serum AMH as a marker for ovarian reserve. Evidence Synthesis Serum AMH levels are measured to assess the “functional ovarian reserve,” a term that is preferred over “ovarian reserve,” since AMH levels reflect the pool of growing follicles that potentially can ovulate. Serum AMH levels are used in individualized follicle-stimulating hormone dosing protocols and may predict the risk of poor response or ovarian hyperstimulation syndrome but has limited value in predicting ongoing pregnancy. Serum AMH levels are studied to predict natural or disease-related age of menopause. Studies show that the age-dependent decline rates of AMH vary among women. The generalized implementation of serum AMH measurement has also led to an increase in diagnostic assays, including automated assays. However, direct comparison of results remains problematic. Conclusion Serum AMH remains the preferred ovarian reserve marker. However, the lack of an international standard for AMH limits comparison between AMH assays. Furthermore, little is known about endogenous and exogenous factors that influence serum AMH levels, which limits proper interpretation of AMH values in a clinical setting.
Role for Selenium in Metabolic Homeostasis and Human Reproduction
Selenium (Se) is a micronutrient essential for life. Dietary intake of Se within the physiological range is critical for human health and reproductive functions. Selenium levels outside the recommended range have been implicated in infertility and variety of other human diseases. However, presently it is not clear how different dietary Se sources are processed in our bodies, and in which form or how much dietary Se is optimum to maintain metabolic homeostasis and boost reproductive health. This uncertainty leads to imprecision in published dietary guidelines and advice for human daily intake of Se and in some cases generating controversies and even adverse outcomes including mortality. The chief aim for this review is to describe the sources of organic and inorganic Se, the metabolic pathways of selenoproteins synthesis, and the critical role of selenprotenis in the thyroid gland homeostasis and reproductive/fertility functions. Controversies on the use of Se in clinical practice and future directions to address these challenges are also described and discussed herein.
Diversity of ageing across the tree of life
Evolution drives, and is driven by, demography. A genotype moulds its phenotype’s age patterns of mortality and fertility in an environment; these two patterns in turn determine the genotype’s fitness in that environment. Hence, to understand the evolution of ageing, age patterns of mortality and reproduction need to be compared for species across the tree of life. However, few studies have done so and only for a limited range of taxa. Here we contrast standardized patterns over age for 11 mammals, 12 other vertebrates, 10 invertebrates, 12 vascular plants and a green alga. Although it has been predicted that evolution should inevitably lead to increasing mortality and declining fertility with age after maturity, there is great variation among these species, including increasing, constant, decreasing, humped and bowed trajectories for both long- and short-lived species. This diversity challenges theoreticians to develop broader perspectives on the evolution of ageing and empiricists to study the demography of more species. Examination of demographic age trajectories for species from a wide range of taxonomic groups shows that these species have very diverse life-history patterns; mortality and reproduction vary greatly with age for both long- and short-lived species, and the relationships between ageing, mortality and reproduction are clearly complex. Multiple approaches to growing old It is usually assumed that ageing is accompanied by decreasing reproductive potential and increasing mortality. But such assumptions might be parochial, as Owen Jones et al . show in this wide-ranging survey of life-history patterns in a variety of animals and plants. It turns out that mortality and fertility rates vary enormously with age, in short- and long-lived species alike. No single pattern fits all. The relationships between ageing, mortality and reproduction are clearly complex, and more work is required to achieve a more general understanding. Theoreticians need to develop models that can more adequately capture the diversity of ageing, and experiments could usefully be carried out on a more diverse set of species.
Male fertility thermal limits predict vulnerability to climate warming
Forecasting which species/ecosystems are most vulnerable to climate warming is essential to guide conservation strategies to minimize extinction. Tropical/mid-latitude species are predicted to be most at risk as they live close to their upper critical thermal limits (CTLs). However, these assessments assume that upper CTL estimates, such as CTmax, are accurate predictors of vulnerability and ignore the potential for evolution to ameliorate temperature increases. Here, we use experimental evolution to assess extinction risk and adaptation in tropical and widespread Drosophila species. We find tropical species succumb to extinction before widespread species. Male fertility thermal limits, which are much lower than CTmax, are better predictors of species’ current distributions and extinction in the laboratory. We find little evidence of adaptive responses to warming in any species. These results suggest that species are living closer to their upper thermal limits than currently presumed and evolution/plasticity are unlikely to rescue populations from extinction. Trait-based approaches assume upper critical thermal limits (CTLs) are good predictors of climate change vulnerability. Here, the authors show that male fertility thermal limits, which are lower than CTLs, are better at predicting Drosophila extinction in the lab, suggesting species may be living close to their thermal limits.
Male reproductive aging arises via multifaceted mating-dependent sperm and seminal proteome declines, but is postponable in Drosophila
Declining ejaculate performance with male age is taxonomically widespread and has broad fitness consequences. Ejaculate success requires fully functional germline (sperm) and soma (seminal fluid) components. However, some aging theories predict that resources should be preferentially diverted to the germline at the expense of the soma, suggesting differential impacts of aging on sperm and seminal fluid and trade-offs between them or, more broadly, between reproduction and lifespan. While harmful effects of male age on sperm are well known, we do not know how much seminal fluid deteriorates in comparison. Moreover, given the predicted tradeoffs, it remains unclear whether systemic lifespan-extending interventions could ameliorate the declining performance of the ejaculate as a whole. Here, we address these problems using Drosophila melanogaster. We demonstrate that seminal fluid deterioration contributes to male reproductive decline via mating-dependent mechanisms that include posttranslational modifications to seminal proteins and altered seminal proteome composition and transfer. Additionally, we find that spermproduction declines chronologically with age, invariant tomating activity such that oldermultiplymated males become infertile principally via reduced sperm transfer and viability. Our data, therefore, support the idea that both germline and soma components of the ejaculate contribute to male reproductive aging but reveal a mismatch in their aging patterns. Our data do not generally support the idea that the germline is prioritized over soma, at least, within the ejaculate. Moreover, we find that lifespan-extending systemic down-regulation of insulin signaling results in improved late-life ejaculate performance, indicating simultaneous amelioration of both somatic and reproductive aging.
The Role of Zinc in Male Fertility
Several studies proposed the importance of zinc ion in male fertility. Here, we describe the properties, roles and cellular mechanisms of action of Zn2+ in spermatozoa, focusing on its involvement in sperm motility, capacitation and acrosomal exocytosis, three functions that are crucial for successful fertilization. The impact of zinc supplementation on assisted fertilization techniques is also described. The impact of zinc on sperm motility has been investigated in many vertebrate and invertebrate species. It has been reported that Zn2+ in human seminal plasma decreases sperm motility and that Zn2+ removal enhances motility. Reduction in the intracellular concentration of Zn2+ during epididymal transit allows the development of progressive motility and the subsequent hyper activated motility during sperm capacitation. Extracellular Zn2+ affects intracellular signaling pathways through its interaction with the Zn2+ sensing receptor (ZnR), also named GPR39. This receptor was found in the sperm tail and the acrosome, suggesting the possible involvement of Zn2+ in sperm motility and acrosomal exocytosis. Our studies showed that Zn2+ stimulates bovine sperm acrosomal exocytosis, as well as human sperm hyper-activated motility, were both mediated by GPR39. Zn2+ binds and activates GPR39, which activates the trans-membrane-adenylyl-cyclase (tmAC) to catalyze cAMP production. The NHE (Na+/H+-exchanger) is activated by cAMP, leading in increased pHi and activation of the sperm-specific Ca2+ channel CatSper, resulting in an increase in [Ca2+]i, which, together with HCO3−, activates the soluble adenylyl-cyclase (sAC). The increase in [cAMP]i activates protein kinase A (PKA), followed by activation of the Src-epidermal growth factor receptor-Pphospholipase C (Src-EGFR-PLC) cascade, resulting in inositol-triphosphate (IP3) production, which mobilizes Ca2+ from the acrosome, causing a further increase in [Ca2+]i and the development of hyper-activated motility. PKA also activates phospholipase D1 (PLD1), leading to F-actin formation during capacitation. Prior to the acrosomal exocytosis, PLC induces phosphadidylinositol-4,5-bisphosphate (PIP2) hydrolysis, leading to the release of the actin-severing protein gelsolin to the cytosol, which is activated by Ca2+, resulting in F-actin breakdown and the occurrence of acrosomal exocytosis.