Menstrual Cycle

The increased growth, popularity, and media interest in women's sport has led to calls for greater prioritisation of female-specific research and innovation. In response, science and medicine researchers have increased the volume of sport-related studies investigating female-specific matters, such as the menstrual cycle. Whilst the accelerated rate of published studies with female participants is welcome, the emerging trend of using assumed or estimated menstrual cycle phases to characterise ovarian hormone profiles is a significant concern. Replacing direct measurements of key characteristics of the menstrual cycle (e.g. the surge in luteinising hormone prior to ovulation via urine detection and sufficient luteal phase progesterone via blood or saliva sampling) with assumptions or estimates (i.e. no measurements) is proposed to be a pragmatic and convenient way of generating data, particularly in field-based research (i.e. elite athlete environments), where time, resources, and athlete availability are sometimes constrained. Using assumed or estimated phases, however, amounts to guessing the occurrence and timing of ovarian hormone fluctuations and risks potentially significant implications for female athlete health, training, performance, injury, etc., as well as resource deployment. The positive intentions of researchers and scientific journals in this space are not in question. The aim of this Current Opinion is to explain why using assumed or estimated menstrual cycle phases is an approach that has little scientific basis and lacks the rigour and appropriate methodological quality to produce valid and reliable data. In doing so, we provide evidence-based responses to common speculation points and offer recommendations for future research.

BackgroundMenstrual health is a recognised important public health issue and is essential for the realisation of gender equality and the achievement of Sustainable Development Goals. This study aimed to explore the menstrual health experiences of young people in Sweden and how the menstrual cycle affects their health and lives. The study also aimed to identify the facilitators and barriers to achieving menstrual health.MethodsWe conducted a qualitative study in Sweden. Sixteen young people aged 18-28 who have experienced the menstrual cycle participated in individual interviews. Purposeful sampling combined with snowball sampling was applied to recruit the participants. The data were analysed using reflexive thematic analysis.ResultsParticipants viewed menstruation as a sign of having a healthy and functioning body. Menstruation was linked to becoming a woman and fostered a sense of community and sisterhood, which was viewed as positive among cis women. Further, the results showed that physical and emotional symptoms related to the menstrual cycle limited the participants' everyday lives and social relationships and had a negative effect on their sexual and mental health. While managing their emotional discomfort and other menstrual complaints, they also had to deal with the public stigma and norms about menstruation contributing to shame and worries. Barriers to menstrual health included stigma and norms related to menstruation, which led to the adoption of expected behaviours, such as avoiding participation in social activities. The normalisation of menstrual complaints also contributed to delays in seeking healthcare, despite having symptoms that had a negative effect on their health. An important factor promoting menstrual health and quality of life is access to prompt treatment to mitigate and decrease symptoms that limit everyday life.ConclusionsThe results indicate that menstrual stigma and related norms create challenging situations limiting menstruating people's everyday lives and reluctance to seek healthcare despite needing to. To promote the menstrual health of menstruating young people in Sweden, organised and systematic screening of menstrual cycle-related symptoms should be provided within student health services at schools and universities, and primary healthcare. Policymakers should consider integrating stigma-reducing efforts into public health interventions to improve general awareness and promote gender equality.

ObjectiveADHD is a neurodevelopmental condition associated with elevated symptoms of inattention and hyperactivity/impulsivity. Symptoms of ADHD typically persist into adulthood and can impair functioning and overall quality of life. In females (including women and people assigned female at birth), ADHD is under-recognized, and knowledge about the relationship between ADHD symptoms and sex hormones is lacking. This systematic review aimed to synthesize the current evidence investigating the relationship between ADHD symptoms (including medication effects) and sex hormones in females.MethodSearches were conducted within Ovid MEDLINE, Embase, and PsycINFO from 1980 to January 2025. Included studies investigated ADHD symptoms in the context of hormonal changes in females, including studies specifically exploring ADHD and sex hormones, as well as hormonal life stages (puberty, menstrual cycle, and pregnancy). Narrative synthesis was utilized for data extraction, grouping studies by hormonal phase.ResultsA total of 11 studies were included in this review. Evidence was largely suggestive of a relationship between ADHD symptoms and sex hormones in females, specifically in puberty and across the menstrual cycle. Findings were limited by the small number of studies reviewed, often with small sample sizes and considerable diversity in participant populations and outcome measures.ConclusionSex hormones and phases related to hormonal changes (such as puberty and the menstrual cycle) may be associated with ADHD symptom changes in females. Further research is needed to understand the relationship between sex hormones and ADHD symptoms and requires investigation of a wider range of hormonal milestones in females, including menopause.

BackgroundScreening premenstrual disorders (PMDs) is time-consuming and challenging, resulting in delays in detection and treatment. To characterize the temporal dynamics of portable digital-marker across the menstrual cycle and its biological basis in PMDs, we investigated the menstrual fluctuation of wearable device-based real-time heart rate variability (HRV) through menstrual cycles and its associations with premenstrual disorders (PMDs) symptoms.MethodsA prospective study of female participants nested from the Care of Premenstrual Emotion Cohort was conducted. Daily HRV metrics were collected by the Huawei Fitness Tracker over 1-2 menstrual cycles. PMDs symptoms were assessed with the Daily Record of Severity of Problems on a daily basis. HRV variability across cycles was described using descriptive statistics and splines, while associations between HRV metrics and PMDs symptoms were estimated using a mixed-effect model.ResultsIn total, 193 participants (with 68 prospectively confirmed PMDs) were included, with measures from 293 menstrual cycles. In both women with and without PMDs, SDNN, rMSSD, and HF decreased before menses and increased afterwards; the increase trends were more pronounced in women without PMDs. During the week before or after menses, levels of these HRV metrics were inversely associated with PMDs symptoms among women with PMDs (e.g., rMSSD, postmenstrual week, β = -0·036 per SD, 95% CI: -0·065 to -0·048), whereas null association was noted for those without PMDs (β = -0·001, 95% CI -0·011 to 0·009; P-for-difference ConclusionsWearable device-estimated HRV fluctuate across menstrual cycles, with varying strengths of association with PMDs symptoms between individuals with and without PMDs, which may facilitate the development of digital biomarkers for future PMDs diagnostics.