Detection of ovulation, a review of currently available methods

Young adult's views on using a poster to learn about fertility: redesigning the fertility education poster

Fertility awareness should be taught to everyone. The International Reproductive Health Education Collaboration (IRHEC) designed a fertility poster in 2019 but did not have a specific target group in mind. Studies have been conducted in Denmark and Sweden to determine how the poster can be redesigned. In this study, we carried out focus groups with young adults in the UK to ask their views of the poster, with the aim of redesigning it. Six focus groups were undertaken with twenty seven, 18-25 year olds. Five questions were asked: 1. What are your thoughts, feelings, and reactions to the poster? 2. Did you learn anything from the poster? 3. How has reading the poster impacted your opinions or thoughts about having children? 4. What are your opinions about using a poster format to inform and start reflections regarding family building? 5. Reading through each point are there any changes to be made? Content analysis was performed. Themes identified revealed the information on the poster gave the participants some anxiety and apprehension, especially regarding the effect of age on fertility, perceptions of IVF, and gaps in knowledge. The fertility education poster is a good resource for education, but other resources should be developed.

Using Wearable Skin Temperature Data to Advance Tracking and Characterization of the Menstrual Cycle in a Real-World Setting

The menstrual cycle is a loop involving the interplay of different organs and hormones, with the capacity to impact numerous physiological processes, including body temperature and heart rate, which in turn display menstrual rhythms. The advent of wearable devices that can continuously track physiological data opens the possibility of using these prolonged time series of skin temperature data to noninvasively detect the temperature variations that occur in ovulatory menstrual cycles. Here, we show that the menstrual skin temperature variation is better represented by a model of oscillation, the cosinor, than by a biphasic square wave model. We describe how applying a cosinor model to a menstrual cycle of distal skin temperature data can be used to assess whether the data oscillate or not, and in cases of oscillation, rhythm metrics for the cycle, including mesor, amplitude, and acrophase, can be obtained. We apply the method to wearable temperature data collected at a minute resolution each day from 120 female individuals over a menstrual cycle to illustrate how the method can be used to derive and present menstrual cycle characteristics, which can be used in other analyses examining indicators of female health. The cosinor method, frequently used in circadian rhythms studies, can be employed in research to facilitate the assessment of menstrual cycle effects on physiological parameters, and in clinical settings to use the characteristics of the menstrual cycles as health markers or to facilitate menstrual chronotherapy.

Vaginal Sensors

The development and market emergence of vaginal sensors have begun to demonstrate their impact on women's healthcare. Until recently, in limited cases, these sensors have exhibited their capabilities in diagnosing and monitoring disorders of the vaginal tract during different stages of women's lives. This Perspective is a compilation of what has been accomplished so far in the landscape of vaginal sensors. The text explores the diverse types of vaginal sensor technologies, their applications, and their potential impact on women's healthcare. The review introduces the anatomy of the vagina and cervix and categorizes vaginal sensors that have been developed, highlighting the technologies and potential applications. The paper covers biomarkers of the vaginal tract and discusses their importance in maintaining the overall characteristics of the vaginal system. The text also explores the clinical implications of vaginal sensors in pregnancy monitoring, disease detection, and sexual health management. In the final step, the manuscript provides future perspectives and possibilities that can be incorporated in the emerging field of vaginal sensors.

Quantitative detection of pre-ovulatory luteinizing hormone surges in urine using the microfluidic vertical agitation approach

Identifying the time of ovulation is an important process for women seeking and avoiding pregnancy. Luteinizing hormone (LH) plays an important role in ovulation, which is very important in the reproductive mechanism. Therefore, detecting the LH level is of great importance in monitoring ovulation. In this study, sensitive, rapid and selective electrochemical biosensors were developed to detect LH quantitatively from human urine samples and to monitor the ovulation period. Isopotential region and current density optimization studies revealed that sensors with an electrode width and spacing of 1 mm had the optimum performance. Electrochemical impedance spectra evidenced immobilization of DSP self-assembled monolayers and anti-LH-beta antibody on the surface. While the mobile phone vibrator led to a 3.5-fold enhancement in response signals, the agitation system developed resulted in a 10-fold improvement. The sensors displayed detection limits of 1.02 and 1.53 mIU/ml in the range of 0-40 mIU/ml LH concentration obtained using two statistical approaches. Additionally, the sensors showed no cross-reactivity to hCG, which is very similar in structure and is widely reported to have high cross-reactivity.

Novel Methodology for Identifying the Occurrence of Ovulation by Estimating Core Body Temperature During Sleeping: Validity and Effectiveness Study

BACKGROUND

Body temperature is the most-used noninvasive biomarker to determine menstrual cycle and ovulation. However, issues related to its low accuracy are still under discussion.

OBJECTIVE

This study aimed to improve the accuracy of identifying the presence or absence of ovulation within a menstrual cycle. We investigated whether core body temperature (CBT) estimation can improve the accuracy of temperature biphasic shift discrimination in the menstrual cycle. The study consisted of 2 parts: experiment 1 assessed the validity of the CBT estimation method, while experiment 2 focused on the effectiveness of the method in discriminating biphasic temperature shifts.

METHODS

In experiment 1, healthy women aged between 18 and 40 years had their true CBT measured using an ingestible thermometer and their CBT estimated from skin temperature and ambient temperature measured during sleep in both the follicular and luteal phases of their menstrual cycles. This study analyzed the differences between these 2 measurements, the variations in temperature between the 2 phases, and the repeated measures correlation between the true and estimated CBT. Experiment 2 followed a similar methodology, but focused on evaluating the diagnostic accuracy of these 2 temperature measurement approaches (estimated CBT and traditional oral basal body temperature [BBT]) for identifying ovulatory cycles. This was performed using urine luteinizing hormone (LH) as the reference standard. Menstrual cycles were categorized based on the results of the LH tests, and a temperature shift was identified using a specific criterion called the "three-over-six rule." This rule and the nested design of the study facilitated the assessment of diagnostic measures, such as sensitivity and specificity.

RESULTS

The main findings showed that CBT estimated from skin temperature and ambient temperature during sleep was consistently lower than directly measured CBT in both the follicular and luteal phases of the menstrual cycle. Despite this, the pattern of temperature variation between these phases was comparable for both the estimated and true CBT measurements, suggesting that the estimated CBT accurately reflected the cyclical variations in the true CBT. Significantly, the CBT estimation method showed higher sensitivity and specificity for detecting the occurrence of ovulation than traditional oral BBT measurements, highlighting its potential as an effective tool for reproductive health monitoring. The current method for estimating the CBT provides a practical and noninvasive method for monitoring CBT, which is essential for identifying biphasic shifts in the BBT throughout the menstrual cycle.

CONCLUSIONS

This study demonstrated that the estimated CBT derived from skin temperature and ambient temperature during sleep accurately captures variations in true CBT and is more accurate in determining the presence or absence of ovulation than traditional oral BBT measurements. This method holds promise for improving reproductive health monitoring and understanding of menstrual cycle dynamics.

Comparative efficacy of exercise, diet and/or pharmacological interventions on BMI, ovulation, and hormonal profile in reproductive-aged women with overweight or obesity: a systematic review and network meta-analysis

BACKGROUND

The increasing prevalence of obesity worldwide poses a significant threat to reproductive function owing, in part, to hormonal disturbances caused by negative feedback between excess adiposity and the hypothalamic-pituitary-ovarian axis. Consequently, finding the most appropriate strategies to lose weight and improve ovulation in women with overweight or obesity is a clinically relevant matter that needs to be investigated. A comprehensive comparison of the independent and combined efficacy of lifestyle and/or pharmacological interventions on BMI, ovulation, and hormonal profile in women with overweight or obesity at risk of anovulatory infertility would facilitate improving fertility strategies in this population.

OBJECTIVE AND RATIONALE

This study aimed to evaluate the comparative efficacy of exercise, diet, and pharmacological interventions on BMI, ovulation, and hormonal profile in reproductive-aged women with overweight or obesity.

SEARCH METHODS

A systematic review was performed by searching PubMed, Scopus, Web of Science, PsycINFO, and Cochrane Library up to 14 December 2023, for randomized controlled trials assessing the effects of exercise, diet and/or pharmacological interventions (i.e. weight-lowering drugs or ovulation inducers) on BMI, ovulation, and/or hormonal profile in reproductive-aged women with overweight or obesity. We performed frequentist random-effect network meta-analyses and rated the certainty of the evidence. The primary outcomes were BMI and ovulation rate, and the secondary outcomes were serum reproductive hormone levels (gonadotrophins, androgens, or oestrogens). We performed sensitivity analyses, including the studies that only involved women with PCOS.

OUTCOMES

Among 1190 records screened, 148 full texts were assessed for eligibility resulting in 95 trials (9910 women), of which 53% presented a high or unclear risk of bias. The network meta-analyses revealed that, compared to control: diet combined with weight-lowering drugs (mean difference (MD) -2.61 kg/m2; 95% CI -3.04 to -2.19; τ2 = 0.22) and adding exercise (MD -2.35 kg/m2; 95% CI -2.81 to -1.89; τ2 = 0.22) led to the greatest decrease in BMI; exercise combined with diet and ovulation inducers (risk ratio (RR) 7.15; 95% CI 1.94-26.40; τ2 = 0.07) and exercise combined with diet and weight-lowering drugs (RR 4.80; 95% CI 1.67-13.84; τ2 = 0.07) produced the highest increase in ovulation rate; and exercise combined with diet and weight-lowering drugs was the most effective strategy in reducing testosterone levels (standardized mean difference (SMD) -2.91; 95% CI -4.07 to -1.74; τ2 = 2.25), the third most effective strategy in increasing sex hormone-binding globulin levels (SMD 2.37; 95% CI 0.99-3.76; τ2 = 2.48), and it was coupled with being ranked first in terms of free androgen index reduction (SMD -1.59; 95% CI -3.18 to 0.01; τ2 = 1.91). The surface under the cumulative ranking curve scores suggested that: diet combined with weight-lowering drugs is the strategy most likely (94%) to produce the highest BMI reduction; and exercise combined with diet and ovulation inducers is the strategy most likely (89%) to produce the highest ovulation rate improvement. The sensitivity analyses, which exclusively included studies involving women diagnosed with PCOS, were consistent with the results presented above.

WIDER IMPLICATIONS

Overall, the findings of this network meta-analysis indicate that the combination of exercise, diet, and pharmacological interventions is effective for weight loss, improving ovulation, and normalizing the androgen levels of women with overweight or obesity. Although higher quality studies are needed, these results support that the optimal treatment strategy for women with overweight or obesity wishing to conceive must consider exercise, diet, and pharmacological interventions during the shared decision-making process.

Infrared Thermal Imaging during the Estrous Cycle in Adult Wistar Rats

The collection and examination method of vaginal smears is the standard for the determination of ovulation or phases of the estrous cycle of rodents used in research. However, this method is time consuming and may not be amenable to continual monitoring of a large number of animals. Infrared thermography has recently emerged as a noninvasive technique that requires relatively little handling of animals. The body temperature of rodents has been shown to correlate with the ocular surface temperature. This study aimed to evaluate the use of thermographic monitoring of the ocular surface for the identification of estrus in rats. Vaginal smears were collected from female Wistar rats (n = 22) for 14 consecutive days. Core body temperature was estimated by measuring ocular surface temperature using a thermal camera; vaginal temperature was measured using a digital thermometer. Average temperatures were calculated for each rat for each phase of the estrous cycle. The highest core body and vaginal temperature were measured during the estrus phase (37.2 ± 0.6 °C and 37.7 ± 0.6 °C, respectively). The temperatures then fell as the rat entered the diestrus phase (36.8 ± 0.5 °C and 37 ± 0.5 °C). The core body temperature was positively correlated with vaginal temperature (r = 0.697, P < 0.001). In conclusion, thermography is a less invasive method of determining estrus in rats as compared with vaginal smear collection. However, thermography is less accurate and requires at least a 12-d period of measurement.

The Menstrual Health Manager (MHM): A Resource to Reduce Discrepancies Between Science and Practice in Sport and Exercise

Inadequate research on female health and performance; the complexity of the research; low menstrual health literacy of athletes, coaches, and support staff; and ethical and cultural sensitivities are all recognized as barriers to effective health monitoring for females in sports. Frameworks have been developed for academics to follow to help improve the quality of female-specific research. However, a similar resource that enables correct terminology, and use of health monitoring techniques has not been provided for sporting organizations, coaches, support staff or athletes. Therefore, this critical commentary presents a new resource, the Menstrual Health Manager. This resource may be used to determine the level of menstrual health monitoring detail that may be used by organisations, coaches or athletes, and specifies what reproductive health details the data will provide. This resource aims to provide organizations and coaches with a means of understanding the data that inform their decisions for female athletes. Utilization of this resource may aid in the consistent use of terminology and methods for female-specific health monitoring in both sports and research.

Usefulness of the Sympto-Thermal Method with Standardized Cervical Mucus Assessment (InVivo Method) for Evaluating the Monthly Cycle in Women with Polycystic Ovary Syndrome (PCOS)

(1) Background: FABMs (fertility awareness-based methods) are methods that rely on the observation of clinical signs related to fertility found in women, the so-called fertility bioindicators. They can be a valuable tool for diagnosing monthly cycle disorders and infertility, for example, among patients with PCOS (polycystic ovary syndrome). Until now, it has been difficult for women with PCOS to use FABM, due to the difficulty of describing fertility bioindicators and their disorders due to the biology of the syndrome. The new InVivo sympto-thermal method with standardized cervical mucus assessment may provide a valuable diagnostic and therapeutic tool for observing the monthly cycle in this group of women. (2) Methods: The monthly cycle was evaluated in a group of 32 women of reproductive age. A total of 108 monthly cycle observation cards were analyzed: 35 monthly cycle cards were collected from 18 women with PCOS, and 73 monthly cycle cards collected from 14 healthy women. In addition, 32 pairs of macroscopic and microscopic images were evaluated: 17 pairs from the study group (four subjects) and 15 pairs from women in the control group (six subjects). (3) Results: We showed that in the group of patients with PCOS, menstruation was longer (p = 0.000814), the number of mucus peaks was statistically higher (p = 0.040747), and the interquartile range (IQR) of the duration of the follicular phase (calculated according to the BBT) was significantly higher (8 days) compared to women in the control group. We also observed that among all the women studied, the microscopic image of cervical mucus correlated with the cycle phase described in the observation card, as determined by reference to the BBT chart, provided that it showed the correct features. (4) Conclusions: Systematic maintenance of monthly cycle observation charts using the InVivo method can be an important supplement to the medical history, as it allows for a thorough assessment of, among others, the timing of monthly bleeding, cervical mucus symptoms, BBT changes, and the duration of the follicular and luteal phases among both healthy and PCOS women.

Consumer wearables and personal devices for tracking the fertile window

The market for technology that tracks ovulation to promote conception is rapidly expanding in the United States, targeting the growing audience of technologically proficient, reproductive-age female consumers. In this narrative review, 23 different, nonprescription wearables and devices designed to help women track their fertile window were identified as currently, commercially available in the United States. The majority of these utilize measurements of basal body temperature or combinations of various urinary hormones. This clinical opinion characterizes the scant available research validating the accuracy of these technologies. It further examines research oversight, discusses the utility of these wearables and devices to consumers, and considers these technologies through an equity lens. The discussion concludes with a call for innovation, describing promising new technologies that not only harness unique physiologic parameters to predict ovulation, but also focus on cost-effectiveness with the hope of increasing access to these currently costly devices and wearables.

Impact of Physiological Fluctuations of Sex Hormones During the Menstrual Cycle on Glucose Metabolism and the Gut Microbiota

Diabetes mellitus is one of the most prevalent chronic diseases. Previous studies have shown differences in glucose metabolism between males and females. Moreover, difficulties in medication adherence have been reported in females with type 2 diabetes. These observations are believed to be caused by fluctuations in sex hormone concentrations during the menstrual cycle. Furthermore, gut microbiota is linked to female host metabolism and sex hormone production. Understanding the interactions between fluctuating hormone concentrations during the menstrual cycle, gut microbiota, and glucose metabolism in humans is significant because of the increasing prevalence of diabetes and the consequent need to expand preventive efforts. A literature search was performed to determine and summarize the existing evidence, deduce future research needs to maintain female health, and investigate the relationship between the physiological menstrual cycle and glucose metabolism. Studies from 1967 to 2020 have already examined the relationship between variations during the menstrual cycle and glucose metabolism in healthy female subjects using an oral-glucose tolerance test or intravenous glucose tolerance test. However, the overall number of studies is rather small and the results are contradictory, as some studies detected differences in glucose concentrations depending on the different cycle phases, whereas others did not. Some studies reported lower glucose levels in the follicular phase than in the luteal phase, whereas another study detected the opposite. Data on gut microbiota in relation to the menstrual cycle are limited. Conflicting results exist when examining the effect of hormonal contraceptives on the gut microbiota and changes in the course of the menstrual cycle. The results indicate that the menstrual cycle, especially fluctuating sex hormones, might impact the gut microbiota composition.The menstrual cycle may affect the gut microbiota composition and glucose metabolism. These results indicate that glucose tolerance may be the greatest in the follicular phase; however, further well-conducted studies are needed to support this assumption.

Letrozole cotreatment progestin-primed ovarian stimulation in women undergoing controlled ovarian stimulation for in vitro fertilization

AIM

To investigate the impact of letrozole cotreatment progestin-primed ovarian stimulation (PPOS) (Le PPOS) in controlled ovarian stimulation (COS) and the pregnancy outcomes in frozen-thawed embryo transfer cycles.

METHODS

This retrospective cohort study included women who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI). A total of 2575 cycles were included (1675 in the Le PPOS group and 900 in the PPOS group). The primary outcome was the clinical pregnancy rates. The secondary outcome was the live birth rates.

RESULTS

In this study, propensity score matching (PSM) was performed to create a perfect match of 379 patients in each group. After matching, the numbers of oocytes retrieved, mature oocytes, fertilization, and clinical pregnancy rates were more favorable in the Le PPOS group than in the PPOS group (all p < 0.05). The multivariable analysis showed that the clinical pregnancy rate was higher in the Le PPOS than in the PPOS group (odds ratio = 1.46, 95% confidence interval: 1.05-2.04, p = 0.024) after adjusting for potentially confounding factors (age, anti-Müllerian hormone levels, antral follicular count, the type of embryo transferred, number of transferred embryos, body mass index, and follicular stimulating hormone and estradiol levels on starting day).

CONCLUSIONS

This retrospective study with a limited sample size suggests that the Le PPOS protocol might be an alternative to the PPOS protocol in women undergoing COS and could lead to better pregnancy outcomes. The results should be confirmed using a formal randomized controlled trial.

Assessing geographical variation in ovulatory cycle knowledge among women of reproductive age in Sierra Leone: Analysis of the 2019 Demographic and Health Survey

BACKGROUND

Sierra Leone has poor indicators of reproductive health and a high prevalence of unintended pregnancies. To date, no study has explored determinants of ovulatory cycle knowledge in Sierra Leone. We investigated geographic region to determine where the needs for improved ovulatory cycle knowledge are greatest in Sierra Leone.

METHODS

This is a cross-sectional study of women of reproductive age (n = 15,574) based on the 2019 Sierra Leone Demographic and Health Survey. Geographic region and sociodemographic covariates were included in a multivariate logistic regression model predicting the odds that participants possessed accurate knowledge of when in the ovulatory cycle pregnancy initiation is most likely.

RESULTS

In Sierra Leone, 39.8% (CI = 37.4-40.9) of 15-49-year-old women had accurate knowledge of the ovulatory cycle. Women in the Northern and Southern regions possessed the highest prevalence of correct knowledge (46.7%, CI = 43.1-50.3 and 45.1%, CI = 41.9-48.2, respectively). Women from the Northwestern (AOR = 0.29, CI = 0.22-0.38), Eastern (AOR = 0.55, CI = 0.41-0.72), and Western regions (AOR = 0.63, CI = 0.50-0.80) had significantly lower odds of accurate ovulatory cycle knowledge compared to others. Women aged 15-19, those with a primary school education, and participants with a parity of none all had the lowest odds of correct ovulatory cycle knowledge as well.

CONCLUSION

Less than four in ten women in Sierra Leone had accurate knowledge of when in the ovulatory cycle pregnancy is most likely to occur. This suggests that family planning outreach programs should include education on the ovulatory cycle and the importance of understanding the implications of its timing. This can reduce the risk of unintended pregnancies throughout Sierra Leone, and can have an especially positive impact in the Northwestern, Eastern, and Western regions, where ovulatory cycle knowledge was significantly lower.

Experiences of users of period tracking apps: which app, frequency of use, data input and output and attitudes

RESEARCH QUESTION

What are the experiences of users of period tracking apps in relation to which apps they use, their frequency of use, the type of data and their attitudes to period tracking apps?

DESIGN

This was an observational mixed-methods study using an online survey designed using Qualtrics XM. The survey included 50 open-ended and multiple choice questions, but only specific questions were analysed in this study. The survey was promoted via social media for 22 days between 30 June and 21 July 2021.

RESULTS

Of the 375 total participants, 326 responses were complete and included in analysis. In the results section further down, this is explained as 330 complete responses, with 4 additional responses excluded due to data inconsistencies. The participants' age range was 14-54 years, with a mean of 26.0 (±7.81) years. Most participants (61.9%) had been using a period tracking app for 2 years or longer. Of these 85.6% entered more data when on their period, 31% at a frequency of once a day. There were approximately equivalent proportions of participants who felt that entering data into their app was either 'part of their normal routine' (43.3%) or 'not a priority' (38.0%). Thematic analysis of the participants' experiences of using period-tracking apps revealed five main themes: symptom tracking and understanding general health; concerns with period start date predictions; the problems with fertility tracking; concerns about cost; and concerns about data privacy.

CONCLUSIONS

The infrequency of data inputting and the wide range of symptoms tracked reflects the differing needs of participants from their period-tracking apps. This highlights the need for increased education and research into understanding the realities of variations in using apps.

Point-of-care impedimetric aptasensor to detect the luteinizing hormone

Luteinizing hormone (LH) is a useful biomarker for identifying ovulation events in the cows to predict the time of ovulation to achieve a high success rate of conception following artificial insemination. Although antibody-based radioimmunoassay and enzyme-linked immunosorbent assay are being used for LH measurement, these techniques are expensive, time-consuming, and require expertise and sophisticated laboratory facilities. So, there is a need for a field-applicable, affordable, easy-to-use method for LH detection. For developing such a specific, quantitative, and inexpensive system, an aptamer-based smartphone-enabled aptasensor has been investigated. The aptamer was used instead of the antibody as a biorecognition element due to its comparative stability at ambient temperature, ease of synthesis, and cost-effectiveness. Electrochemical impedance spectroscopy has been used to obtain label-free detection of LH within 20 min in ~ 20 μL sample volume. The screen-printed gold electrode is compatible with a smartphone-enabled miniaturized device (Sensit Smart; Palmsens BV, The Netherlands) and was fabricated with the aptamer to detect LH in biological fluids (limit of detection 0.80 and 0.61 ng/mL in buffer and undiluted/unprocessed serum, respectively, with the dynamic range of detection of 0.01 to 50 ng/mL). All the data were obtained in the 10 kHz to 0.10 Hz frequency range at a bias potential of 0.30 V with an alternating potential of 10 mV. The clinical relevance of the sensor was evaluated in 10 serum samples collected from dairy animals which established a high correlation with standard LH-ELISA (κ > 0.87). The aptasensor can be stored at room temperature for 30 days without any significant loss in electrochemical sensing ability.

Reversible female contraceptives: historical, current, and future perspectives†

Contraception is a practice with extensive and complicated social and scientific histories. From cycle tracking, to the very first prescription contraceptive pill, to now having over-the-counter contraceptives on demand, family planning is an aspect of healthcare that has undergone and will continue to undergo several transformations through time. This review provides a comprehensive overview of current reversible hormonal and non-hormonal birth control methods as well as their mechanism of action, safety, and effectiveness specifically for individuals who can become pregnant. Additionally, we discuss the latest Food and Drug Administration (FDA)-approved hormonal method containing estetrol and drospirenone that has not yet been used worldwide as well as the first FDA-approved hormonal over-the-counter progestin-only pills. We also review available data on novel hormonal delivery through microchip, microneedle, and the latest FDA-approved non-hormonal methods such as vaginal pH regulators. Finally, this review will assist in advancing female contraceptive method development by underlining constructive directions for future pursuits. Information was gathered from the NCBI and Google Scholars databases using English and included publications from 1900 to present. Search terms included contraceptive names as well as efficacy, safety, and mechanism of action. In summary, we suggest that investigators consider the side effects and acceptability together with the efficacy of contraceptive candidate towards their development.

Changes in Exhaled Carbon Dioxide during the Menstrual Cycle and Menopause

Introduction

The menstrual cycle (MC) reflects multifaceted hormonal changes influencing women's metabolism, making it a key aspect of women's health. Changes in hormonal levels throughout the MC have been demonstrated to influence various physiological parameters, including exhaled carbon dioxide (CO2). Lumen is a small handheld device that measures metabolic fuel usage via exhaled CO2. This study leverages exhaled CO2 patterns measured by the Lumen device to elucidate metabolic variations during the MC, which may hold significance for fertility management. Additionally, CO2 changes are explored in menopausal women with and without hormonal replacement therapy (HRT).

Methods

This retrospective cohort study analyzed exhaled CO2 data from 3,981 Lumen users, including eumenorrheal women and menopausal women with and without HRT. Linear mixed models assessed both CO2 changes of eumenorrheal women during the MC phases and compared between menopausal women with or without HRT.

Results

Eumenorrheic women displayed cyclical CO2 patterns during the MC, characterized by elevated levels during the menstrual, estrogenic and ovulation phases and decreased levels during post-ovulation and pre-menstrual phases. Notably, despite variations in cycle length affecting the timing of maximum and minimum CO2 levels within a cycle, the overall pattern remained consistent. Furthermore, CO2 levels in menopausal women without HRT differed significantly from those with HRT, which showed lower levels.

Conclusion

This study reveals distinct CO2 patterns across MC phases, providing insights into hormonal influences on metabolic activity. Menopausal women exhibit altered CO2 profiles in relation to the use or absence of HRT. CO2 monitoring emerges as a potential tool for tracking the MC and understanding metabolic changes during menopause.

Can Wrist-Worn Medical Devices Correctly Identify Ovulation?

(1) Background: Hormonal fluctuations across the menstrual cycle lead to multiple changes in physiological parameters such as body temperature, cardiovascular function, respiratory rate and perfusion. Electronic wearables analyzing those parameters might present a convenient alternative to urinary ovulation tests for predicting the fertile window. (2) Methods: We conducted a prospective observational study including women aged 18-45 years without current hormonal therapy who used a wrist-worn medical device and urinary ovulation tests for a minimum of three cycles. We analyzed the accuracy of both the retrospective and prospective algorithms using a generalized linear mixed-effects model. The findings were compared to real-world data from bracelet users who also reported urinary ovulation tests. (3) Results: A total of 61 study participants contributing 205 cycles and 6081 real-life cycles from 3268 bracelet users were included in the analysis. The mean error in identifying ovulation with the wrist-worn medical device retrospective algorithm in the clinical study was 0.31 days (95% CI -0.13 to 0.75). The retrospective algorithm identified 75.4% of fertile days, and the prospective algorithm identified 73.8% of fertile days correctly within the pre-specified equivalence limits (±2 days). The quality of the retrospective algorithm in the clinical study could be confirmed by real-world data. (4) Conclusion: Our data indicate that wearable sensors may be used to accurately detect the periovulatory period.

The definition of unexplained infertility: A systematic review

BACKGROUND

There is no consensus on tests required to either diagnose unexplained infertility or use for research inclusion criteria. This leads to heterogeneity and bias affecting meta-analysis and best practice advice.

OBJECTIVES

This systematic review analyses the variability of inclusion criteria applied to couples with unexplained infertility. We propose standardised criteria for use both in future research studies and clinical diagnosis.

SEARCH STRATEGY

CINAHL and MEDLINE online databases were searched up to November 2022 for all published studies recruiting couples with unexplained infertility, available in full text in the English language.

DATA COLLECTION AND ANALYSIS

Data were collected in an Excel spreadsheet. Results were analysed per category and methodology or reference range.

MAIN RESULTS

Of 375 relevant studies, only 258 defined their inclusion criteria. The most commonly applied inclusion criteria were semen analysis, tubal patency and assessment of ovulation in 220 (85%), 232 (90%), 205 (79.5%) respectively. Only 87/220 (39.5%) studies reporting semen analysis used the World Health Organization (WHO) limits. Tubal patency was accepted if bilateral in 145/232 (62.5%) and if unilateral in 24/232 (10.3%). Ovulation was assessed using mid-luteal serum progesterone in 115/205 (56.1%) and by a history of regular cycles in 87/205 (42.4%). Other criteria, including uterine cavity assessment and hormone profile, were applied in less than 50% of included studies.

CONCLUSIONS

This review highlights the heterogeneity among studied populations with unexplained infertility. Development and application of internationally accepted criteria will improve the quality of research and future clinical care.

Changes in body weight and body composition during the menstrual cycle

OBJECTIVES

The general perception is that menstrual cycle is a factor related to body weight and body composition fluctuations in women. The lack of a standardized methodology of the so far conducted studies has led to controversial results. The aim of the current study is to identify if there are any changes in body weight and body composition during the menstrual cycle.

METHODS

In the current study measurements of body weight, circumferences, skinfolds and body composition with bioelectrical impedance analysis were conducted twice per week in 42 women during their menstrual cycle.

RESULTS

Body weight was found to be statistically significantly higher during menstruation compared to the first week of the menstrual cycle by 0.450 kg, which could be attributed to a statistically significant increase of 0.474 kg observed in extracellular water. No other statistically significant changes were observed regarding body composition.

CONCLUSIONS

An increase of approximately 0.5 kg was observed during women's menstrual cycle, mostly due to extracellular fluid retention at menstruation days. These findings could be taken into account to interpret body weight and composition periodic fluctuations in women of reproductive age.

Analyzing physiological signals recorded with a wearable sensor across the menstrual cycle using circular statistics

This study aims to identify the most significant features in physiological signals representing a biphasic pattern in the menstrual cycle using circular statistics which is an appropriate analytic method for the interpretation of data with a periodic nature. The results can be used empirically to determine menstrual phases. A non-uniform pattern was observed in ovulating subjects, with a significant periodicity (p< 0.05) in mean temperature, heart rate (HR), Inter-beat Interval (IBI), mean tonic component of Electrodermal Activity (EDA), and signal magnitude area (SMA) of the EDA phasic component in the frequency domain. In contrast, non-ovulating cycles displayed a more uniform distribution (p> 0.05). There was a significant difference between ovulating and non-ovulating cycles (p< 0.05) in temperature, IBI, and EDA but not in mean HR. Selected features were used in training an Autoregressive Integrated Moving Average (ARIMA) model, using data from at least one cycle of a subject, to predict the behavior of the signal in the last cycle. By iteratively retraining the algorithm on a per-day basis, the mean temperature, HR, IBI and EDA tonic values of the next day were predicted with root mean square error (RMSE) of 0.13 ± 0.07 (C°), 1.31 ± 0.34 (bpm), 0.016 ± 0.005 (s) and 0.17 ± 0.17 (μS), respectively.

Timed intercourse for couples trying to conceive

BACKGROUND

Many factors influence fertility, one being the timing of intercourse. The 'fertile window' describes a stage in the cycle when conception can occur and is approximately five days before to several hours after ovulation. 'Timed intercourse' is the practice of prospectively identifying ovulation and, thus, the fertile window to increase the likelihood of conception. Methods of predicting ovulation include urinary hormone measurement (luteinising hormone (LH) and oestrogen), fertility awareness-based methods (FABM) (including tracking basal body temperatures, cervical mucus monitoring, calendar charting/tracking apps), and ultrasonography. However, there are potentially negative aspects associated with ovulation prediction, including stress, time consumption, and cost implications of purchasing ovulation kits and app subscriptions. This review considered the evidence from randomised controlled trials (RCTs) evaluating the use of timed intercourse (using ovulation prediction) on pregnancy outcomes.

OBJECTIVES

To evaluate the benefits and risks of ovulation prediction methods for timing intercourse on conception in couples trying to conceive.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility (CGF) Group Specialised Register, CENTRAL, MEDLINE, and Embase in January 2023. We also checked the reference lists of relevant studies and searched trial registries for any additional trials.

SELECTION CRITERIA

We included RCTs that compared methods of timed intercourse using ovulation prediction to other forms of ovulation prediction or intercourse without ovulation prediction in couples trying to conceive.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane to select and analyse studies in this review. The primary review outcomes were live birth and adverse events (such as depression and stress). Secondary outcomes were clinical pregnancy, pregnancy (clinical or positive urinary pregnancy test not yet confirmed by ultrasound), time to pregnancy, and quality of life. We assessed the overall quality of the evidence for the main comparisons using GRADE methods.

MAIN RESULTS

This review update included seven RCTs involving 2464 women or couples. Four of the five studies from the previous review were included in this update, and three new studies were added. We assessed the quality of the evidence as moderate to very low, the main limitations being imprecision, indirectness, and risk of bias. Urinary ovulation tests versus intercourse without ovulation prediction Compared to intercourse without ovulation prediction, urinary ovulation detection probably increases the chance of live birth in couples trying to conceive (risk ratio (RR) 1.36, 95% confidence interval (CI) 1.02 to 1.81, 1 RCT, n = 844, moderate-quality evidence). This suggests that if the chance of a live birth without urine ovulation prediction is 16%, the chance of a live birth with urine ovulation prediction is 16% to 28%. However, we are uncertain whether timed intercourse using urinary ovulation detection resulted in a difference in stress (mean difference (MD) 1.98, 95% CI -0.87 to 4.83, I² = 0%, P = 0.17, 1 RCT, n = 77, very low-quality evidence) or clinical pregnancy (RR 1.09, 95% CI 0.51 to 2.31, I² = 0%, 1 RCT, n = 148, low-quality evidence). Similar to the live birth result, timed intercourse using urinary ovulation detection probably increases the chances of clinical pregnancy or positive urine pregnancy test (RR 1.28, 95% CI 1.09 to 1.50, I² = 0, 4 RCTs, n = 2202, moderate-quality evidence). This suggests that if the chance of a clinical pregnancy or positive urine pregnancy test without ovulation prediction is assumed to be 18%, the chance following timed intercourse with urinary ovulation detection would be 20% to 28%. Evidence was insufficient to determine the effect of urine ovulation tests on time to pregnancy or quality of life. Fertility awareness-based methods (FABM) versus intercourse without ovulation prediction Due to insufficient evidence, we are uncertain whether timed intercourse using FABM resulted in a difference in live birth rate compared to intercourse without ovulation prediction (RR 0.95, 95% CI 0.76 to 1.20, I² = 0%, 2 RCTs, n = 157, low-quality evidence). We are also uncertain whether FABM affects stress (MD -1.10, 95% CI -3.88 to 1.68, 1 RCT, n = 183, very low-quality evidence). Similarly, we are uncertain of the effect of timed intercourse using FABM on anxiety (MD 0.5, 95% CI -0.52 to 1.52, P = 0.33, 1 RCT, n = 183, very low-quality evidence); depression (MD 0.4, 95% CI -0.28 to 1.08, P = 0.25, 1 RCT, n = 183, very low-quality evidence); or erectile dysfunction (MD 1.2, 95% CI -0.38 to 2.78, P = 0.14, 1 RCT, n = 183, very low-quality evidence). Evidence was insufficient to detect a benefit of timed intercourse using FABM on clinical pregnancy (RR 1.13, 95% CI 0.31 to 4.07, 1 RCT, n = 17, very low-quality evidence) or clinical or positive pregnancy test rates (RR 1.08, 95% CI 0.89 to 1.30, 3 RCTs, n = 262, very low-quality evidence). Finally, we are uncertain whether timed intercourse using FABM affects the time to pregnancy (hazard ratio 0.86, 95% CI 0.53 to 1.38, 1 RCT, n = 140, low-quality evidence) or quality of life. No studies assessed the use of timed intercourse with pelvic ultrasonography.

AUTHORS' CONCLUSIONS

The new evidence presented in this review update shows that timed intercourse using urine ovulation tests probably improves live birth and pregnancy rates (clinical or positive urine pregnancy tests but not yet confirmed by ultrasound) in women under 40, trying to conceive for less than 12 months, compared to intercourse without ovulation prediction. However, there are insufficient data to determine the effects of urine ovulation tests on adverse events, clinical pregnancy, time to pregnancy, and quality of life. Similarly, due to limited data, we are uncertain of the effect of FABM on pregnancy outcomes, adverse effects, and quality of life. Further research is therefore required to fully understand the safety and effectiveness of timed intercourse for couples trying to conceive. This research should include studies reporting clinically relevant outcomes such as live birth and adverse effects in fertile and infertile couples and utilise various methods to determine ovulation. Only with a comprehensive understanding of the risks and benefits of timed intercourse can recommendations be made for all couples trying to conceive.

Endocrine factors associated with infertility in women: an updated review

INTRODUCTION

Infertility is defined as the inability to conceive after unprotected sexual intercourse for at least 12 consecutive months. Our objective is to present an updated narrative review on the endocrine causes of infertility in women.

AREAS COVERED

A comprehensive review was conducted using Scielo, Scopus, and EMBASE databases, comprising 245 articles. The pathophysiology of infertility in women was described, including endocrinopathies such as hypothalamic amenorrhea, hyperprolactinemia, polycystic ovary syndrome, primary ovarian insufficiency, obesity, thyroid dysfunction, and adrenal disorders. The diagnostic approach was outlined, emphasizing the necessity of hormonal studies and ovarian response assessments. Additionally, the treatment plan was presented, commencing with non-pharmacological interventions, encompassing the adoption of a Mediterranean diet, vitamin supplementation, moderate exercise, and maintaining a healthy weight. Subsequently, pharmacological treatment was discussed, focusing on the management of associated endocrine disorders and ovulatory dysfunction.

EXPERT OPINION

This comprehensive review highlights the impact of endocrine disorders on fertility in women, providing diagnostic and therapeutic algorithms. Despite remaining knowledge gaps that hinder more effective treatments, ongoing research and advancements show promise for improved fertility success rates within the next five years. Enhanced comprehension of the pathophysiology behind endocrine causes and the progress in genetic research will facilitate the delivery of personalized treatments, thus enhancing fertility rates.

Finding of the optimal preparation and timing of endometrium in frozen-thawed embryo transfer: a literature review of clinical evidence

Frozen-thawed embryo transfer (FET) has been a viable alternative to fresh embryo transfer in recent years because of the improvement in vitrification methods. Laboratory-based studies indicate that complex molecular and morphological changes in endometrium during the window of implantation after exogenous hormones with controlled ovarian stimulation may alter the interaction between the embryo and endometrium, leading to a decreased implantation potential. Based on the results obtained from randomized controlled studies, increased pregnancy rates and better perinatal outcomes have been reported following FET. Compared to fresh embryo transfer, fewer preterm deliveries, and reduced incidence of ovarian hyperstimulation syndrome were found after FETs, yet there is a trend of increased pregnancy-related hypertensive diseases in women receiving FET. Despite the increased application of FET, the search for the most optimal priming protocol for the endometrium is still undergoing. Three available FET protocols have been proposed to prepare the endometrium: i) natural cycle (true natural cycle and modified natural cycle) ii) artificial cycle (AC) or hormone replacement treatment cycle iii) mild ovarian stimulation (mild-OS) cycle. Emerging evidence suggests that the optimal timing for FET using warmed blastocyst transfer is the LH surge+6 day, hCG administration+7 day, and the progesterone administration+6 day in the true natural cycle, modified natural cycle, and AC protocol, respectively. Although still controversial, better clinical pregnancy rates and live birth rates have been reported using the natural cycle (true natural cycle/modified natural cycle) compared with the AC protocol. Additionally, a higher early pregnancy loss rate and an increased incidence of gestational hypertension have been found in FETs using the AC protocol because of the lack of a corpus luteum. Although the common clinical practice is to employ luteal phase support (LPS) in natural cycles and mild-OS cycles for FET, the requirement for LPS in these protocols remains equivocal. Recent findings obtained from RCTs do not support the routine application of endometrial receptivity testing to optimize the timing of FET. More RCTs with rigorous methodology are needed to compare different protocols to prime the endometrium for FET, focusing not only on live birth rate, but also on maternal, obstetrical, and neonatal outcomes.

Using Hormone Data and Age to Pinpoint Cycle Day within the Menstrual Cycle

Background and Objectives: Menstrual cycle tracking is essential for reproductive health and overall well-being. However, there is still an over-reliance on estimations that standard cycles are 28 days long, divided evenly between the follicular and luteal phases. Due to the variability of cycle length and cycle phase lengths, common methods of identifying where an individual is in their cycle are often inaccurate. This study used daily hormone monitoring obtained through a remote hormone-monitoring platform to evaluate hormone levels across a menstrual cycle to identify nuances in the follicular and luteal phases in individuals of different age groups. Materials and Methods: This study used a remote fertility testing system that quantitatively tracks luteinizing hormone (LH) and pregnanediol-3-glucuronide (PdG) through urine tests read by an AI-powered smartphone app. The study analyzed cycle data from 1233 users with a total of 4123 evaluated cycles. Daily levels for LH and PdG were monitored across multiple cycles. Results: This study determined that calculated cycle lengths tended to be shorter than user-reported cycle lengths. Significant differences were observed in cycle phase lengths between age groups, indicating that follicular phase length declines with age while luteal phase length increases. Finally, the study found that if an individual's age, first cycle day, and current hormone levels are known, population-level hormone data can be used to pinpoint which cycle phase and cycle day they are in with 95% confidence. Conclusions: At-home hormone monitoring technologies can allow patients and clinicians to track their cycles with greater precision than when relying on textbook estimations. The study's findings have implications for fertility planning, clinical management, and general health monitoring. Prior to this study, no standard existed for pinpointing where a person was in their cycle through only one measure of LH and PdG. These findings have the potential to fill significant gaps within reproductive healthcare and beyond.

Determinants of knowledge of the highest conception probability period among reproductive age women in Low-Income African countries: A multilevel analysis based on the recent Demographic and Health Survey

BACKGROUND

Adequate knowledge about the highest conception probability period in the reproductive cycle allows individuals and couples to attain or avoid their fertility probabilities. Poor knowledge of conception probability period leads to undesirable outcomes like unwanted pregnancy, miscarriage, and abortion. Determinants of knowledge of highest conception probability period were not well studied on economically disadvantaged countries. Therefore, our study aimed to identify individual and community level factors of knowledge of the highest conception probability period among women of reproductive age in low income African countries.

METHODS

The appended and latest Demographic and Health Survey datasets of 15 low-income African countries was used for analysis. Model fitness was done using the Intraclass correlation coefficient, median odds ratio, and deviance. A model with the lowest deviance (model-III) was selected as the best model. Multilevel logistic regression model was used to identify determinant factors of knowledge of the highest conception probability period. In the final model, adjusted odds ratio with 95% confidence interval was reported and variables with p<0.05 were considered as statistically significant with knowledge of the highest conception probability period.

RESULTS

Total weighted sample of 235,574 reproductive aged women with a median age of 27 years were included. The correct knowledge of the highest conception probability period among the study participants was 24.04% (95%CI = 23.87-24.22%). Maternal age groups ((20-24 (AOR = 1.49; 95%CI = 1.44-1.55), 25-29 (AOR = 1.62; 1.56-1.68), 35-39 (AOR = 1.76; 1.68-1.84), 40-44 (AOR = 1.75; 1.67-1.83), and 45-49 (AOR = 1.83; 1.74-1.93)), marital status((currently in union (AOR = 1.75; 1.16; 1.13-1.20), formerly in union (AOR = 1.75; 1.11; 1.06-1.16)), better educational status ((secondary (AOR = 2.08; 2.01-2.14) and higher(AOR = 3.36; 3.18-3.55)), higher wealth index ((middle (AOR = 1.08; 1.04-1.12), richer (AOR = 1.24; 1.20-1.28), and richest (AOR = 1.51; 1.45-1.57)), knowledge of contraceptive methods (AOR = 2.63; 2.49-2.77), current contraceptive use (AOR = 1.14; 1.11-1.16), and urban residency (AOR = 1.26; 1.21-1.29) were statistically significant with knowledge of the highest conception probability period.

CONCLUSION

In this study, knowledge of the highest conception probability period among women of reproductive age in low-income African countries was low. Therefore, improving the fertility awareness through comprehensive reproductive education or counseling could be one of the operational ways to control unintended pregnancy.

Intrauterine Insemination After Human Chorionic Gonadotropin Trigger or Luteinizing Hormone Surge: A Meta-analysis

OBJECTIVE

To assess the odds of pregnancy after intrauterine insemination (IUI) timed by ultrasound monitoring and human chorionic gonadotropin (hCG) administration compared with monitoring luteinizing hormone (LH) levels.

DATA SOURCES

We searched PubMed (MEDLINE), EMBASE (Elsevier), Scopus (Elsevier), Web of Science (Clarivate Analytics), ClinicalTrials.gov (National Institutes of Health), and the Cochrane Library (Wiley) from the inception until October 1, 2022. No language limitations were applied.

METHODS OF STUDY SELECTION

After deduplication, 3,607 unique citations were subjected to blinded independent review by three investigators. Thirteen studies (five retrospective cohort, four cross-sectional, two randomized controlled trials, and two randomized crossover studies) that enrolled women undergoing natural cycle, oral medication (clomid or letrozole), or both for IUI were included in the final random-effects model meta-analysis. Methodologic quality of included studies was assessed with the Downs and Black checklist.

TABULATION, INTEGRATION, AND RESULTS

Data extraction was compiled by two authors, including publication information, hCG and LH monitoring guidelines, and pregnancy outcomes. No significant difference in odds of pregnancy between hCG administration and endogenous LH monitoring was observed (odds ratio [OR] 0.92, 95% CI 0.69-1.22, P=.53). Subgroup analysis of the five studies that included natural cycle IUI outcomes also showed no significant difference in odds of pregnancy between the two methods (OR 0.88, 95% CI 0.46-1.69, P=.61). Finally, a subgroup analysis of 10 studies that included women who underwent ovarian stimulation with oral medications (clomid or letrozole) did not demonstrate a difference in odds of pregnancy between ultrasonography with hCG trigger and LH-timed IUI (OR 0.88, 95% CI 0.66-1.16, P=.32). Statistically significant heterogeneity was noted between studies.

CONCLUSION

This meta-analysis showed no difference between pregnancy outcomes between at-home LH monitoring and timed IUI.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42021230520.

A multi-site study of the relationship between photoperiod and ovulation rate using Natural Cycles data

Many species exhibit seasonal patterns of breeding. Although humans can shield themselves from many season-related stressors, they appear to exhibit seasonal patterns of investment in reproductive function nonetheless, with levels of sex steroid hormones being highest during the spring and summer months. The current research builds on this work, examining the relationship between day length and ovarian function in two large samples of women using data from the Natural Cycles birth control application in each Sweden and the United States. We hypothesized that longer days would predict higher ovulation rates and sexual motivation. Results revealed that increasing day length duration predicts increased ovulation rate and sexual behavior, even while controlling for other relevant factors. Results suggest that day length may contribute to observed variance in women's ovarian function and sexual desire.

Increase of body temperature immediately after ovulation in mares

To successfully inseminate mares, precise detection of ovulation time is crucial, especially when using frozen-thawed semen. Monitoring body temperature, as has been described in women, could be a non-invasive way to detect ovulation. The objective of this study was to investigate the relationship between the time of ovulation and the variation of body temperature in mares based on automatic continuous measurements during estrus. The experimental group included 21 mares for 70 analyzed estrous cycles. When the mares showed estrous behavior, they were administered intramuscular deslorelin acetate (2.25 mg) in the evening. At the same time, monitoring of body temperature using a sensor device fixed at the left lateral thorax was started and continued for over 60 h. In 2-hour intervals, transrectal ultrasonography was performed to detect ovulation. Estimated body temperature in the 6 h following ovulation detection was on average 0.06°C +/- 0.05°C (mean +/- SD) significantly higher when compared with body temperature at the same time on the preceding day (p=0.01). In addition, a significant effect of PGF_2α administration for estrus induction on the body temperature was found, being significantly higher until 6 h before ovulation compared to that of uninduced cycles (p=0.005). In conclusion, changes in body temperature during estrus in mares were related to ovulation. The increase in body temperature immediately after ovulation might be used in the future to establish automatized and non-invasive systems to detect ovulation. However, the identified temperature rise is relatively small on average and hardly identifiable in the individual mares.

Menstrual Dysfunction in Adolescents with Chronic Illness: A Systematic Review

STUDY OBJECTIVE

Menstrual dysfunction can impact both the physical and emotional health of young people¹. Multiple chronic disease have been associated with menstrual dysfunction in adults², however there is little research in adolescents, despite non adherence and sub-optimal illness control in this group. We aimed to identify the impact chronic illness has on the age of menarche (AAM) and the menstrual cycle in adolescents.

METHODS

Studies were extracted of female adolescents aged 10-19 who had a chronic physical illness. Data included outcomes on age of menarche and/or menstrual cycle quality. Exclusion criteria aimed to exclude diseases where menstrual dysfunction was a known part of the disease pathophysiology i.e. polycystic ovarian syndrome³, or in which medications were used that directly impacted gonadal function⁴. A literature search (to January 2022) was performed on EMBASE, PubMed and Cochrane library databases. Two widely used modified quality analysis tools were used.

RESULTS

Our initial search netted 1451 articles, of which 95 full texts were examined and 43 met inclusion criteria. 27 papers focussed on Type 1 Diabetes (T1D), with 8 papers examining adolescents with cystic fibrosis (CF) and the remaining studying inflammatory bowel disease (IBD), juvenile idiopathic arthritis (JIA), coeliac disease and chronic renal disease. Metanalysis of 933 patients with T1D versus 5244 controls demonstrated a significantly later AAM in T1D (by 0.42 years; p=<0.00001). There was also a significant association between higher HbA1c and insulin dose (IU/kg) and later age of menarche. Eighteen papers reviewed other aspects of menstruation, including dysmenorrhoea, oligomenorrhoea, amenorrhoea and ovulatory function, with variable findings.

CONCLUSION

The majority of studies were small and in single populations. Despite this, there was evidence of delayed menarche and some evidence of irregular menses in those with CF and T1D. Further structured studies are needed to evaluate menstrual dysfunction in adolescents and how it relates to their chronic illness.

A report of two cases with successful oocyte retrieval after wrongly earlier injection of ovulation induction trigger: Case report

Oocyte maturation is induced by trigger administration and is acritical step in the success of assisted reproductive technology (ART)treatment. The ideal time interval between trigger administration and oocyte retrieval varies in the literature. Extremely short or long time intervals are both knownto cause unfavorable outcomes in oocyte collection. Accurate control over theinterval between trigger injection and oocyte retrieval is very important forwomen undergoing in vitro fertilization (IVF), to avoid unexpected premature ovulation. In this report, we present two infertile women who mistakenly injected the triggering dose of gonadotropin releasing hormone agonist (GnRHa) 12 h earlier. Case 1 and case 2 were 23 and 30 years old, respectively. Therewas no intervention to prevent pre-operative ovulation, and oocyte retrievalhas been done 48-50 h after trigger injection. oocytes and embryos quality wereacceptable. In conclusion, in patients who have the wrong trigger injection, oocyte retrieval is recommended after consulting the patient about theadvantages and disadvantages of the oocyte retrieval operation.

The molecular consequences of androgen activity in the human breast

Estrogen and progesterone have been extensively studied in the mammary gland, but the molecular effects of androgen remain largely unexplored. Transgender men are recorded as female at birth but identify as male and may undergo gender-affirming androgen therapy to align their physical characteristics and gender identity. Here we perform single-cell-resolution transcriptome, chromatin, and spatial profiling of breast tissues from transgender men following androgen therapy. We find canonical androgen receptor gene targets are upregulated in cells expressing the androgen receptor and that paracrine signaling likely drives sex-relevant androgenic effects in other cell types. We also observe involution of the epithelium and a spatial reconfiguration of immune, fibroblast, and vascular cells, and identify a gene regulatory network associated with androgen-induced fat loss. This work elucidates the molecular consequences of androgen activity in the human breast at single-cell resolution.

Current evidence shows no influence of women's menstrual cycle phase on acute strength performance or adaptations to resistance exercise training

Introduction

The bias towards excluding women from exercise science research is often due to the assumption that cyclical fluctuations in reproductive hormones influence resistance exercise performance and exercise-induced adaptations.

Methods

Hence, the purpose of this umbrella review was to examine and critically evaluate the evidence from meta-analyses and systematic reviews on the influence of menstrual cycle phase on acute performance and chronic adaptations to resistance exercise training (RET).

Results

We observed highly variable findings among the published reviews on the ostensible effects of female sex hormones on relevant RET-induced outcomes, including strength, exercise performance, and hypertrophy.

Discussion

We highlight the importance of comprehensive menstrual cycle verification methods, as we noted a pattern of poor and inconsistent methodological practices in the literature. In our opinion, it is premature to conclude that short-term fluctuations in reproductive hormones appreciably influence acute exercise performance or longer-term strength or hypertrophic adaptations to RET.

The effect of progesterone supplementation for luteal phase support in natural cycle frozen embryo transfer: a systematic review and meta-analysis based on randomized controlled trials

IMPORTANCE

The necessity of progesterone supplementation for luteal phase support (LPS) in natural cycle frozen embryo transfer (NC-FET) cycles warrants further confirmation.

OBJECTIVE

To investigate the effect of progesterone supplementation for LPS on the reproductive outcomes of patients undergoing NC-FET cycles.

DATA SOURCES

The PubMed, Ovid-Embase, Cochrane Library, Web of Science, CNKI, Wanfang, VIP, and CBM were electronically searched. The search time frame was from inception up to September 2022.

STUDY SELECTION AND SYNTHESIS

Randomized controlled trials (RCTs) that used progesterone for LPS in NC-FET cycles, including true NC-FET cycles (tNC-FET) and modified NC-FET cycles (mNC-FET), were included. The counted data were analyzed using relative risk (RR) as the effect-size statistic, and each effect size was assigned its 95% confidence interval (CI).

MAIN OUTCOME MEASURES

The primary outcomes were the live birth rate (LBR) and the clinical pregnancy rate (CPR), and the secondary outcome was the miscarriage rate.

RESULTS

Four RCTs were included, which involved 1116 participants. The results of the meta-analysis showed that progesterone supplementation was associated with increased LBR (RR, 1.42; 95% CI, 1.15-1.75; I² = 0%, moderate-quality evidence) and CPR (RR, 1.30, 95% CI, 1.07-1.57; I² = 0%, moderate-quality evidence) in patients undergoing NC-FET cycles. Subgroup analysis showed that progesterone supplementation was associated with higher LBR and CPR in tNC-FET cycles. However, no association was found between increased LBR and CPR in mNC-FET cycles. In addition, only one RCT reported that oral dydrogesterone had similar CPR and miscarriage rate compared with vaginal progesterone in mNC-FET cycles.

CONCLUSION(S)

Overall, moderate-quality evidence suggested that progesterone supplementation for LPS was associated with increased LBR and CPR in NC-FET cycles. Progesterone supplementation was associated with a higher LBR and CPR in tNC-FET cycles. However, the effectiveness of progesterone supplementation in mNC-FET cycles should be further verified by larger RCTs. Low to very low-quality evidence indicated that oral dydrogesterone and vaginal progesterone have similar reproductive outcomes in mNC-FET cycles, which requires further study, especially in tNC-FET cycles.

REGISTRATION NUMBER

PROSPERO CRD42022355550 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=355550) was registered on September 3, 2022.

Predicting serum hormone concentration by estimation of urinary hormones through a home-use device

STUDY QUESTION

Can a home-use device be used to predict serum hormone levels?

SUMMARY ANSWER

A home-use device can predict urinary hormone values which are well-correlated to serum concentrations of respective hormones and hence can be used as a proxy for serum measurements.

WHAT IS KNOWN ALREADY

Home-use devices that predict ovulation are calibrated against the actual day of ovulation. However, the correlation of any quantitative system to serum hormone concentrations has not been established.

STUDY DESIGN SIZE DURATION

A total of 73 data points obtained from 20 participants across different phases of the menstrual cycle, i.e. bleeding days, follicular phase and luteal phase were used to establish the correlation between serum hormones and urinary metabolite values. Single data points from 20 random users were used to assess the correlation established.

PARTICIPANTS/MATERIALS SETTING METHODS

Participants were women in the fertile age groups and only current users of the home-use device. Selection was done based on inclusion and exclusion criteria. Blood hormones were tested using chemiluminescent immunoassays and urinary measurements were taken on the home-use device at home.

MAIN RESULTS AND THE ROLE OF CHANCE

Serum estradiol (E2), progesterone (P4) and LH were correlated with urinary estrone-3-glucuronide (E3G), pregnanediol glucuronide (PdG) and LH with an R ² of 0.96, 0.95 and 0.98, respectively. Repredicted serum concentration obtained by using the correlation equation had a correlation of 0.92, 0.94 and 0.93 in unknown samples.

LIMITATIONS REASONS FOR CAUTION

The study was designed to include women who have normal cycle lengths regularly; therefore, the values obtained were in the normal range. Certain infertility conditions may cause the values to be higher and correlation in such cases needs to be established.

WIDER IMPLICATIONS OF THE FINDINGS

The results of this study imply a new tool that can be used by fertility specialists as a proxy for blood tests whenever required. Extended study on this system can enable its use in assisted reproductive techniques as well.

STUDY FUNDING/COMPETING INTERESTS

No funding was received for this study. S.P. and D.D. are employees of the research and development division of Samplytics Technologies Pvt. Ltd. which is a forwarder for Inito Inc., USA. A.R. and V.A.V. are co-founders of Inito Inc., USA.

TRIAL REGISTRATION NUMBER

The trial was registered at the International Standard Randomised Controlled Trial Number (ISRCTN) registry (Identifier: ISRCTN15534557).

Multifunctional 4D-Printed Sperm-Hybrid Microcarriers for Assisted Reproduction

Remotely controllable microrobots are appealing for various biomedical in vivo applications. In particular, in recent years, our group has focused on developing sperm-microcarriers to assist sperm cells with motion deficiencies or low sperm count (two of the most prominent male infertility problems) to reach the oocyte toward in-vivo-assisted fertilization. Different sperm carriers, considering their motion in realistic media and confined environments, have been optimized. However, the already-reported sperm carriers have been mainly designed to transport single sperm cell, with limited functionality. Thus, to take a step forward, here, the development of a 4D-printed multifunctional microcarrier containing soft and smart materials is reported. These microcarriers can not only transport and deliver multiple motile sperm cells, but also release heparin and mediate local enzymatic reactions by hyaluronidase-loaded polymersomes (HYAL-Psomes). These multifunctional facets enable in situ sperm capacitation/hyperactivation, and the local degradation of the cumulus complex that surrounds the oocyte, both to facilitate the sperm-oocyte interaction for the ultimate goal of in vivo assisted fertilization.

Confirmation of human ovulation in assisted reproduction using an adhesive axillary thermometer (femSense®)

Objective

Timing for sexual intercourse is important in achieving pregnancy in natural menstrual cycles. Different methods of detecting the fertile window have been invented, among them luteinization hormone (LH) to predict ovulation and biphasic body basal temperature (BBT) to confirm ovulation retrospectively. The gold standard to detect ovulation in gynecology practice remains transvaginal ultrasonography in combination with serum progesterone. In this study we evaluated a wearable temperature sensing patch (femSense®) using continuous body temperature measurement to confirm ovulation and determine the end of the fertile window.

Methods

96 participants received the femSense® system consisting of an adhesive axillary thermometer patch and a smartphone application, where patients were asked to document information about their previous 3 cycles. Based on the participants data, the app predicted the cycle length and the estimated day of ovulation. From these predictions, the most probable fertile window and the day for applying the patch were derived. Participants applied and activated the femSense® patch on the calculated date, from which the patch continuously recorded their body temperature throughout a period of up to 7 days to confirm ovulation. Patients documented their daily urinary LH test positivity, and a transvaginal ultrasound was performed on day cycle day 7, 10, 12 and 14/15 to investigate the growth of one dominant follicle. If a follicle reached 15 mm in diameter, an ultrasound examination was carried out every day consecutively until ovulation. On the day ovulation was detected, serum progesterone was measured to confirm the results of the ultrasound. The performance of femSense® was evaluated by comparing the day of ovulation confirmation with the results of ovulation prediction (LH test) and detection (transvaginal ultrasound).

Results

The femSense® system confirmed ovulation occurrence in 60 cases (81.1%) compared to 48 predicted cases (64.9%) with the LH test (p = 0.041). Subgroup analysis revealed a positive trend for the femSense® system of specific ovulation confirmation within the fertile window of 24 h after ovulation in 42 of 74 cases (56.8%). Cycle length, therapy method or infertility reason of the patient did not influence accuracy of the femSense® system.

Conclusions

The femSense® system poses a promising alternative to the traditional BBT method and is a valuable surrogate marker to transvaginal ultrasound for confirmation of ovulation.

AACC Guidance Document on the Use of Point-of-Care Testing in Fertility and Reproduction

Background

The AACC Academy revised the reproductive testing section of the Laboratory Medicine Practice Guidelines: Evidence-Based Practice for Point-of-Care Testing (POCT) published in 2007.

Methods

A panel of Academy members with expertise in POCT and laboratory medicine was formed to develop guidance for the use of POCT in reproductive health, specifically ovulation, pregnancy, premature rupture of membranes (PROM), and high-risk deliveries. The committee was supplemented with clinicians having Emergency Medicine and Obstetrics/Gynecology training.

Results

Key recommendations include the following. First, urine luteinizing hormone (LH) tests are accurate and reliable predictors of ovulation. Studies have shown that the use of ovulation predicting kits may improve the likelihood of conception among healthy fertile women seeking pregnancy. Urinary LH point-of-care testing demonstrates a comparable performance among other ovulation monitoring methods for timing intrauterine insemination and confirming sufficient ovulation induction before oocyte retrieval during in vitro fertilization. Second, pregnancy POCT should be considered in clinical situations where rapid diagnosis of pregnancy is needed for treatment decisions, and laboratory analysis cannot meet the required turnaround time. Third, PROM testing using commercial kits alone is not recommended without clinical signs of rupture of membranes, such as leakage of amniotic fluid from the cervical opening. Finally, fetal scalp lactate is used more than fetal scalp pH for fetal acidosis due to higher success rate and low volume of sample required.

Conclusions

This revision of the AACC Academy POCT guidelines provides recommendations for best practice use of POCT in fertility and reproduction.

Tracking of menstrual cycles and prediction of the fertile window via measurements of basal body temperature and heart rate as well as machine-learning algorithms

BACKGROUND

Fertility awareness and menses prediction are important for improving fecundability and health management. Previous studies have used physiological parameters, such as basal body temperature (BBT) and heart rate (HR), to predict the fertile window and menses. However, their accuracy is far from satisfactory. Additionally, few researchers have examined irregular menstruators. Thus, we aimed to develop fertile window and menstruation prediction algorithms for both regular and irregular menstruators.

METHODS

This was a prospective observational cohort study conducted at the International Peace Maternity and Child Health Hospital in Shanghai, China. Participants were recruited from August 2020 to November 2020 and followed up for at least four menstrual cycles. Participants used an ear thermometer to assess BBT and wore the Huawei Band 5 to record HR. Ovarian ultrasound and serum hormone levels were used to determine the ovulation day. Menstruation was self-reported by women. We used linear mixed models to assess changes in physiological parameters and developed probability function estimation models to predict the fertile window and menses with machine learning.

RESULTS

We included data from 305 and 77 qualified cycles with confirmed ovulations from 89 regular menstruators and 25 irregular menstruators, respectively. For regular menstruators, BBT and HR were significantly higher during fertile phase than follicular phase and peaked in the luteal phase (all P < 0.001). The physiological parameters of irregular menstruators followed a similar trend. Based on BBT and HR, we developed algorithms that predicted the fertile window with an accuracy of 87.46%, sensitivity of 69.30%, specificity of 92.00%, and AUC of 0.8993 and menses with an accuracy of 89.60%, sensitivity of 70.70%, and specificity of 94.30%, and AUC of 0.7849 among regular menstruators. For irregular menstruators, the accuracy, sensitivity, specificity and AUC were 72.51%, 21.00%, 82.90%, and 0.5808 respectively, for fertile window prediction and 75.90%, 36.30%, 84.40%, and 0.6759 for menses prediction.

CONCLUSIONS

By combining BBT and HR recorded by the Huawei Band 5, our algorithms achieved relatively ideal performance for predicting the fertile window and menses among regular menstruators. For irregular menstruators, the algorithms showed potential feasibility but still need further investigation.

TRIAL REGISTRATION

ChiCTR2000036556. Registered 24 August 2020.

Impact of Body Mass Index on Muscle Strength, Thicknesses, and Fiber Composition in Young Women

High body mass index (BMI) may influence muscle strength, muscle thickness (Mtk), and fiber composition. We evaluated these parameters in 31 and 27 women grouped in non-oral contraceptive (non-OC) groups and OC groups, respectively, and further divided them into groups based on BMI: BMI_low, BMI_norm, and BMI_high. Maximum isometric force (F_max), Mtk, and the relative percentage of muscle fiber composition (%) were examined in both groups. F_max and Mtk values were significantly greater in the BMI_high than the BMI_low within the OC group. However, there was no significant difference in the non-OC group. BMI_low and BMI_norm groups showed a difference in the distribution of muscle fiber types 1 and 2 with almost the same proportions in both non-OC and OC groups. However, the BMI_high group showed a difference in the distribution of muscle fiber types 1 and 2, with type 1 about 18.76% higher in the non-OC group. Contrastively, type 2 was about 34.35% higher in the OC group. In this study, we found that there was a significant difference in F_max and Mtk according to the BMI level in the OC group, but no significant difference was found in the non-OC group. Moreover, the distribution of type 2 muscle fibers tended to be higher in the OC group of BMI_high, although the sample size was small. Therefore, although no significant difference of F_max and Mtk was found according to BMI level in the non-OC group in this study, the increase in BMI level appeared to be more associative of muscle strength in the OC group. Based on the present results, future studies are needed that consider the BMI level as well as the presence or absence of OC in future research about women's muscle strength.

A Comparison of App-Defined Fertile Days from Two Fertility Tracking Apps using Identical Cycle Data

OBJECTIVE

The Natural Cycles app employs daily basal body temperature to define the fertile window via a proprietary algorithm and is clinically established effective in preventing pregnancy. We sought to i) compare the app-defined fertile window of Natural Cycles to that of CycleProGo™, an app that uses BBT and cervical mucus to define the fertile window and ii) compare the app-defined fertile windows to the estimated physiologic fertile window.

STUDY DESIGN

Daily BBT were entered into Natural Cycles from 20 randomly selected regularly cycling women with at least 12 complete cycles from the CycleProGo database. The proportion of cycles with equivalent (+/-1 cycle day) fertile-window starts and fertile-window ends was determined. The app -defined fertile windows were then compared to the estimated physiologic fertile window using Peak mucus to estimate ovulation.

RESULTS

Fifty seven percent of cycles (136/238) had equivalent fertile-window starts and 36% (72/181) had equivalent fertile-window end days. The mean overall fertile-window length from Natural Cycles was 12.8 days compared to 15.1 days for CycleProGo (p<0.001). The Natural Cycles algorithm declared 12%-30% of cycles with a fertile-window start and 13%-38% of cycles with a fertile-window end within the estimated physiologic fertile window. The CycleProGo algorithm declared 4%-14% of cycles with a fertile-window start and no cycles with a fertile-window end within the estimated physiologic fertile window.

CONCLUSIONS

Natural Cycles designated a higher proportion of cycles days as infertile within the estimated physiologic fertile window than CycleProGo.

IMPLICATIONS

Use of cervical mucus in addition to BBT may improve the accuracy of identifying the fertile window. Additional studies with other markers of ovulation and the fertile window would give additional insight into the clinical implications of app-defined fertile window differences.

The impact of a group based, remotely delivered weight loss intervention in women with polycystic ovary syndrome on ovulation, quality of life and body composition

Background

Obesity and visceral adiposity are associated with anovulation. The most common cause of anovulatory infertility in women of reproductive age is polycystic ovary syndrome (PCOS). We conducted this formative study to examine the effects of a remotely delivered, group-based lifestyle program for women with overweight/obesity and PCOS on ovulation, PCOS related quality of life (PCOSQ) and body composition.

Methods

Women with anovulatory infertility caused by PCOS (N = 12) were enrolled in a 6-month high-intensity weight management intervention. Participants were asked to attend 45 min., group behavioral lifestyle sessions, delivered remotely by a registered dietitian weekly across the 6-mo. study and comply with a reduced energy diet, increased physical activity (225 min/wk.), and self-monitoring of weight, physical activity and diet. Diets consisted of five portion-controlled meals (three shakes + two entrees), at least five servings of fruits/vegetables, and ad libitum non-caloric beverages daily. Wilcoxon signed-rank tests were used to assess changes in outcomes across the intervention.

Results

Twelve women received the weight loss intervention (mean age = 32.7 ± 4.2 yrs., BMI = 36.8 ± 4.5 kg/m², 92% college educated), and 8 completed the intervention. Eight (67%) women reported ovulating during the intervention with an average time to ovulation of 57 ± 45 days. Women lost an average of 3.85 ± 5.94 kg (p = 0.02), decreased their BMI (−1.61 ± 1.09 kg/m²; p = 0.04), and waist circumference (−4.54 ± 3.03 cm; p = 0.04) over the 6-mo. intervention. Additionally, self-reported menstrual problems measured by PCOSQ significantly improved over the study (p = 0.03).

Conclusion

A multicomponent group-based, remotely delivered, lifestyle intervention delivered remotely is a feasible and potentially scalable option to achieve clinically relevant (>3%) weight loss in women with PCOS.

Clinical trial registration

www.clinicaltrials.gov, identifier: NCT03677362.

Basal and dynamic relationships between serum anti-Müllerian hormone and gonadotropins in patients with functional hypothalamic amenorrhea, with or without polycystic ovarian morphology

BACKGROUND

To evaluate in women with functional hypothalamic amenorrhea (FHA), whether there is a difference between patients with and without polycystic ovarian morphology (PCOM) concerning the response to a gonadotropin releasing hormone (GnRH) stimulation test and to pulsatile GnRH treatment.

METHODS

In a retrospective observational study, 64 women with FHA who underwent a GnRH stimulation test and 32 age-matched controls without PCOM were included. Pulsatile GnRH treatment was provided to 31 FHA patients and three-month follow-up data were available for 19 of these.

RESULTS

Serum levels of gonadotropins and estradiol were lower in FHA women than in controls (p < 0.05). FHA patients revealed PCOM in 27/64 cases (42.2%). FHA patients without PCOM revealed lower anti-Müllerian hormone (AMH) levels than controls (median 2.03 ng/mL, IQR 1.40-2.50, versus 3.08 ng/mL, IQR 2.24-4.10, respectively, p < 0.001). Comparing FHA patients with and without PCOM, the latter revealed lower AMH levels, a lower median LH increase after the GnRH stimulation test (240.0%, IQR 186.4-370.0, versus 604.9%, IQR 360.0-1122.0; p < 0.001) as well as, contrary to patients with PCOM, a significant increase in AMH after three months of successful pulsatile GnRH treatment (median 1.69 ng/mL at baseline versus 2.02 ng/mL after three months of treatment; p = 0.002).

CONCLUSIONS

In women with FHA without PCOM, the phenomenon of low AMH levels seems to be based on relative gonadotropin deficiency rather than diminished ovarian reserve. AMH tended to rise after three months of pulsatile GnRH treatment. The differences found between patients with and without PCOM suggest the former the existence of some PCOS-specific systemic and/or intra-ovarian abnormalities.

Luteinizing Hormone Dynamics in Menstruation

Menstruation is a finely-controlled cycle that responds to the prevailing endocrine and paracrine environment. However, social stigma has led to inadequate menstrual literacy, both among academics and the larger public. The poorly understood mechanisms of menstruation ultimately lead to suboptimal healthcare treatment and services for biological females, culminating in a physical, financial, and emotional burden. Various hormones signal the beginning and end of each stage of menstruation. In particular, luteinizing hormone (LH) is a major player in ovulation, corpus luteum function, and the stimulation of other key hormones. A LH model could be used to understand the larger control system of menstruation if analyzed in conjunction with models for other major hormones (e.g., FSH, progesterone, and GnRH). Thus, exploring a smaller subsection of LH dynamics within the larger control system of menstruation can lead to a greater understanding of menstruation, contributing towards therapeutics and research for women's health. Using parameters and kinetic equations in the existing body of literature, a transfer function was derived to model LH dynamics. Analysis of system stability reveals overdamped dynamics in LH sensitization at baseline, and underdamped mildly resonant dynamics at the peak of the menstrual cycle, the strength of which depends on the values of the rate constants of LH receptor formation, binding, and desensitization.

General infertility workup in times of high assisted reproductive technology efficacy

The assessments of oocyte quality and quantity and endocrine profile have traditionally been the cornerstone of the general workup of couples with infertility. Over the years, several clinical, hormonal, and functional biomarkers have been adopted to assess ovarian function and identify endocrine disorders before assisted reproductive technology. Furthermore, the genetic workup of patients has drastically changed, introducing novel markers. This not only allowed the prediction of response to ovarian stimulation but also contributed toward the development of a safer and more efficient management of women undergoing assisted reproductive technology. The scope of this review is to provide an overview of the current and novel strategies adopted for the assessment of ovarian function and ovulatory and endocrine disorders in women planning to conceive. Furthermore, it aims to provide an insight in the role of novel genetic biomarkers and use of expanded carrier screening as part of preliminary workup of women with infertility.

Enhanced Originality of Ideas in Women During Ovulation: A Within-Subject Design Study

The signaling theory suggests that creativity may have evolved as a signal for mates. Indeed, its aesthetic value might not have been necessary for survival, but it could have helped to attract a mate, fostering childbearing. If we consider creativity as such a signal, we should expect it will be enhanced in the context related to sexual selection. This hypothesis was tested mainly for men. However, both men and women display physical and mental traits that can attract a mate. Previous studies showed that women can be more creative during their peak fertility. We advanced these findings in the present study, applying reliable measures of menstrual cycle phases (examining saliva and urine samples) and the highly recommended within-subject design. We also introduced and tested possible mediators of the effect. We found women’s ideas to be more original during ovulation compared to non-fertile phases of the ovulatory cycle. The results are discussed in the context of signaling theory and alternative explanations are considered.

What We Have Learned from Animal Models to Understand the Etiology and Pathology of Endometrioma-Related Infertility

Endometrioma (OMA) is the most common subtype of endometriosis, in which the endometriotic lesions are implanted in the ovary. Women with OMA are usually associated with infertility, presenting with reduced ovarian reserve, low oocyte quantity and quality, and poor fertility outcomes. However, the underlying pathological mechanisms in OMA-related infertility are still unclear. Due to the limitations and ethical issues of human studies in reproduction, animal models that recapitulate OMA characteristics and its related infertility are critical for mechanistic studies and subsequent drug development, preclinical testing, and clinical trials. This review summarized the investigations of OMA-related infertility based on previous and latest endometrioma models, providing the possible pathogenesis and potential therapeutic targets for further studies.

Effects of oral contraceptive use on muscle strength, muscle thickness, and fiber size and composition in young women undergoing 12 weeks of strength training: a cohort study

Background

It is suspected that hormonal fluctuations during menstruation may cause different responses to strength training in women who use oral contraceptives (OC) versus those who do not. However, previous studies that investigated the existence of such differences produced conflicting results. In this study, we hypothesized that OC use has no effect on muscle strength and hypertrophy among women undergoing strength training. Thus, we compared the differences in muscle strength and thickness among women who used OCs and those who did not.

Methods

We investigated the influence of OC use on muscle strength (F_max), muscle thickness (Mtk), type 1-to-type 2 muscle fiber (NO) ratio, muscle fiber thickness (MFT), and nuclear-to-fiber (N/F) ratio. Seventy-four healthy young women (including 34 who used OCs and 40 who did not) underwent 12 weeks of submaximal strength training, after which F_max was evaluated using a leg-press machine with a combined force and load cell, while Mtk was measured using real-time ultrasonography. Moreover, the NO ratio, MFT, and N/F ratio were evaluated using muscle needle biopsies.

Results

Participants in the non-OC and OC groups experienced increases in F_max (+ 23.30 ± 10.82 kg and + 28.02 ± 11.50 kg respectively, p = 0.073), Mtk (+ 0.48 ± 0.47 cm² and + 0.50 ± 0.44 cm² respectively, p = 0.888), F_max/Mtk (+ 2.78 ± 1.93 kg/cm² and + 3.32 ± 2.37 kg/cm² respectively, p = 0.285), NO ratio (type 2 fibers: + 1.86 ± 6.49% and − 4.17 ± 9.48% respectively, p = 0.169), MFT (type 2 fibers: + 7.15 ± 7.50 µm and + 4.07 ± 9.30 µm respectively, p = 0.435), and N/F ratio (+ 0.61 ± 1.02 and + 0.15 ± 0.97 respectively, p = 0.866) after training. There were no significant differences between the non-OC and OC groups in any of these parameters (p > 0.05).

Conclusions

The effects of 12 weeks of strength training on F_max, muscle thickness, muscle fiber size, and composition were similar in young women irrespective of their OC use.