Prevalence and clinical picture of premenstrual syndrome in females from Bulgaria

Global burden and trends in female premenstrual syndrome study during 1990-2019

PURPOSE

Premenstrual syndrome (PMS) is prevalent worldwide and considered a crucial issue regarding women's health. In the present study, the Global Burden of Disease (GBD) Study 2019 dataset was utilized to assess the distributional trends in PMS burden and prevalence in regional, national, and sociodemographic index (SDI) categories.

METHODS

The analytical methods and approaches used in the 2019 GBD study were adopted to investigate the incidence rates and disability-adjusted life years (DALY) related to PMS in 204 countries or regions. Age-standardized incidence rates (ASIR), 95% uncertainty intervals (95% UI), and annual percentage changes (EAPC) were calculated from the data.

RESULTS

The global incidence and disability-adjusted life years of PMS exhibited a declining trend in the year 2019. Regions with medium-low SDI had the greatest burden of PMS, with the regions of South Asia (ASR = 7337.9 per 10,000) exhibiting the greatest Age-standardized incidence rates, while the high-income North American states presented the fastest upward trends in Age-standardized disability-adjusted life year rates. At the national level, 107 nations exhibited a decreasing trend in PMS incidence ASR, while 97 nations exhibited an increasing trend, with the United States presenting the greatest increase.

CONCLUSIONS

The present study highlighted that even though the global PMS incidence and disability-adjusted life years have decreased from the year 1990 to 2019, PMS remains a prevalent health concern for women worldwide. While addressing preventive measures and treatment, it is also important to consider the regional and national differences in PMS to develop further effective and targeted health policies.

Prevalence and correlates of premenstrual syndrome and premenstrual dysphoric disorder among women aged 18-25 in Turkey

OBJECTIVE

Premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD) are experienced in the luteal phase among women of reproductive age and are known to affect quality of life. This study sought to determine the prevalence and correlates of PMS and PMDD in women aged 18-25 in Turkey.

METHOD

A cross-sectional study was conducted between December 2022 and May 2023, which recruited 1125 female college students. A personal information form, the International Physical Activity Questionnaire, and the Premenstrual Syndrome Scale (PMSS) were administered. Participants who met criteria for PMS during three consecutive menstrual cycles based on the ACOG and PMSS scores were diagnosed as having PMS. Participants who met the criteria for PMDD during three consecutive menstrual cycles based on the DSM-V were diagnosed as having PMDD. Logistic regression analysis was used to determine correlates of PMS and PMDD.

FINDINGS

PMS was found in 49.2% and PMDD in 48.0% of the participants. Women having a blood group type B compared to those with blood group type A were more likely to have PMS (OR = 151.8, 95% CI = 54.5-422.6). In addition, women with PMS were less likely to be physically active based on the metabolic equivalent of task score (OR = 0.99, 95% CI= 0.98-0.99). Menstrual cycle duration was also longer among those with PMDD (OR = 1.47, 95% CI= 1.25-1.72), as was daily caffeine intake (OR = 1.01, 95% CI= 1.00-1.01). PMDD score was also found to be associated with major depressive disorder (OR = 1.06,95% = 1.05-1.07).

CONCLUSIONS

PMS and PMDD among young women in Turkey were associated with blood groups, MET scores, and other clinical characteristics that may help clinicians to identify these conditions.

Development and validation of risk prediction model for premenstrual syndrome in nurses: results from the nurses-based the TARGET cohort study

Objective

Premenstrual syndrome (PMS) stands as a significant concern within the realm gynecological disorders, profoundly impacting women of childbearing age in China. However, the elusive nature of its risk factors necessitates investigation. This study, therefore, is dedicated to unraveling the intricacies of PMS by focusing on nurses, a cohort with unique occupational stressors, to develop and validate a predictive model for assessing the risk of PMS.

Methods

This investigation employed a multi-center cross-sectional analysis drawing upon data from the TARGET Nurses' health cohort. Utilizing online survey versions of the Premenstrual Syndrome Scale (PMSS), a comprehensive dataset encompassing physiological, social, psychological, occupational, and behavioral variables was collected from 18,645 participants. A stepwise multivariate logistic regression analysis was conducted to identify independent risk factors for PMS. Furthermore, a refined variable selection process was executed, combining the Least Absolute Shrinkage and Selection Operator (LASSO) method with 10-fold cross-validation. The visualization of the risk prediction model was achieved through a nomogram, and its performance was evaluated using the C index, receiver operating characteristic (ROC) curves, and the calibration curves.

Results

Among the diverse variables explored, this study identified several noteworthy predictors of PMS in nurses, including tea or coffee consumption, sleep quality, menstrual cycle regularity, intermenstrual bleeding episodes, dysmenorrhea severity, experiences of workplace bullying, trait coping style, anxiety, depression and perceived stress levels. The prediction model exhibited robust discriminatory power, with an area under the curve of 0.765 for the training set and 0.769 for the test set. Furthermore, the calibration curve underscored the model's high degree of alignment with observed outcomes.

Conclusion

The developed model showcases exceptional accuracy in identifying nurses at risk of PMS. This early alert system holds potential to significantly enhance nurses' well-being and underscore the importance of professional support.

The prevalence, risk factors and lifestyle patterns of Jordanian females with premenstrual syndrome: a cross-sectional study

Aim

The study aims to assess factors associated with premenstrual syndrome (PMS) and the frequency of using painkillers to relieve premenstrual pain.

Methods

This is a cross-sectional study of 1580 premenopausal women. An online self-administered questionnaire consists of sociodemographics, and the diagnostic criteria using the Arabic Premenstrual Syndrome Scale (A-PMS).

Results

The prevalence of PMS among Jordanian females was 94%. Moreover, a significant correlation was found between several factors, including BMI, family history of PMS, smoking, and herbal tea consumption and the psychological, physical and behavioral symptoms of PMS. Furthermore, analgesic use for pain relief and food cravings were significantly associated with psychological, physical and behavioral PMS symptoms.

Conclusion

PMS is highly prevalent and affects women in different life aspects.

The Effect of a Mindfulness-Based Stress Reduction Program on Premenstrual Symptoms: A Randomized Controlled Trial

INTRODUCTION

Premenstrual syndrome (PMS) is an important health problem that affects women of childbearing age. Mindfulness, a meditation practice that cultivates the acceptance of events as they occur in the moment without judgment, is a promising strategy to help women cope with PMS. This study aimed to test the efficacy of a mindfulness-based stress reduction (MBSR) program in decreasing premenstrual symptoms compared with a control group.

METHODS

This study was a prospective, single-masked randomized controlled trial conducted between February and April 2022 with 90 university students. Participants were women between 20 and 30 years of age, scored at least 45 on the Premenstrual Syndrome Scale (PMSS), and were not receiving other treatments for PMS. Participants were randomized into experimental (MBSR) and control groups in a 1:1 allocation. MBSR was provided in 8 weekly sessions lasting 2.5 hours and a 6-hour silence retreat during week 6. Symptoms of PMS were evaluated with the PMSS at baseline and postintervention. Differences between groups were compared postintervention using analysis of covariance to correct for baseline scores. The study was registered at www.

CLINICALTRIALS

gov before the data collection process was initiated (NCT05191108).

RESULTS

Of the 90 enrolled participants, 74 participants completed the study and postintervention assessment (37 in each group). Immediately postintervention, the women in the experimental group had significantly lower PMS symptoms than women in the control group (PMSS total score, 96.35 vs 123.02; P < .001). The effect size for the change in premenstrual symptoms was large (partial η2 , 0.510). Specific symptoms measured by the PMSS subscales all showed significant reductions in scores in the MBSR group compared with the control group.

DISCUSSION

A mindfulness stress reduction program was effective in reducing premenstrual symptoms. MBSR programs may be used as a therapy for PMS. Future studies should test MBSR in larger and more diverse groups of women with PMS.

Association of inflammation biomarkers with food cravings and appetite changes across the menstrual cycle

IMPORTANCE

Premenstrual symptoms, including food cravings, are often a regular complaint among menstruating women. However, existing evidence regarding the biological mechanisms by which these food cravings occur remains unclear. Inflammation may play an essential role in the occurrence of these food cravings before menstruation.

OBJECTIVE

The purpose of the present study was to examine the associations between inflammatory markers and the risk of moderate/severe food cravings while accounting for changes in hormone levels and stress across the menstrual cycle.

DESIGN, SETTING, AND PARTICIPANTS

The BioCycle Study followed women (n = 259) aged 18-44 for two menstrual cycles. Food cravings (via questionnaire) were assessed up to four times per cycle. Each assessment corresponded to menses and mid-follicular, ovulation, and luteal phases of the menstrual cycle. A wide range of cytokine and chemokine levels (hsCRP, GCSF, GMCSF, IL-4, IL-6, RANTES, MIP1B, etc.) were assessed in blood samples collected at up to 8 visits per cycle, with visits timed using fertility monitors.

MAIN OUTCOMES AND MEASURES

Cravings for chocolate, sweets, salty, and other foods, and changes in appetite were determined to estimate the odds of moderate or severe cravings. Associations between inflammatory markers and risk of reporting a moderate/severe craving symptom at each cycle visit was determined using weighted generalized linear models (e.g., marginal structural models). Models were adjusted for age, BMI, and race, as well as time-varying covariates such as estradiol, stress, leptin, and total energy intake, and accounted for repeated measures (i.e., multiple cycles per woman). Both inflammatory markers and reports of cravings were modeled to account for variation at each visit.

RESULTS

An association between higher inflammatory biomarkers such as hsCRP, GCSF, GMCSF, IL-4, IL-6, RANTES, MIP, and increased risk of moderate/severe cravings were identified across the menstrual cycle all risk ratio>1, all CIs range 0.71-2.38. hsCRP retained statistical significance after false discovery rate correction with chocolate, sweet, and salty cravings, while GCSF, GMCSF, IL-6, and RANTES retained significance with chocolate and sweet cravings only.

CONCLUSION

and Relevance: The results suggest a potential role of inflammation in food cravings and appetite changes across the menstrual cycle.

Investigation of coping behaviors and premenstrual syndrome among university students

This study aims to examine premenstrual syndrome (PMS) in university students and their coping behaviors. 452 female students were included in this descriptive and correlational study. The data were collected using a descriptive information form, the Premenstrual Syndrome Scale (PMSS), and the Premenstrual Change Coping Inventory (PMS-Cope). PMS symptoms were found in 80.5% of students. Seeking positive affect-inducing activities to cope with PMS was found to be a significant predictor of reducing the severity of PMS (β =-0.265, p < .001). In coping with PMS, it is necessary to consider the perceptions of taking medication, seeking social support, or seeking positive affect-inducing activities as a coping method to determine the social and cultural beliefs of university students and control PMS. PMS is a significant health problem and raising awareness of the issue alone may not be enough. It should also be noted that the severity of PMS can vary markedly between ethnic groups, and women's strategies for coping with symptoms and their effectiveness may differ between cultures. It is pivotal to develop strategies for university students to cope with PMS and provide personalized care.

Association of Inflammation Biomarkers with Food Cravings and Appetite Changes Across the Menstrual Cycle

Background

Premenstrual symptoms, including food cravings, are often a regular complaint among menstruating women. However, existing evidence regarding the biological mechanisms by which these food cravings occur remains unclear. Inflammation may play an essential role in the occurence of these food cravings before menstruation.

Purpose

The purpose of the present study was to examine the associations between inflammatory markers and the risk of moderate/severe food cravings while accounting for changes in hormone levels and stress across the menstrual cycle.

Methods

The BioCycle Study followed women (n=259) aged 18-44 for two menstrual cycles. Food cravings (via questionnaire) were assessed up to four times per cycle. Each assessment corresponded to menses and mid-follicular, ovulation, and luteal phases of the menstrual cycle. A wide range of cytokine and chemokine levels (hsCRP, GCSF, GMCSF, IL-4, IL-6, RANTES, MIP1B, etc.) were assessed in blood samples collected at up to 8 visits per cycle, with visits timed using fertility monitors. Cravings for chocolate, sweets, salty, and other foods, and changes in appetite were determined to estimate the odds of moderate or severe cravings. Associations between inflammatory markers and risk of reporting a moderate/severe craving symptom at each cycle visit was determined using weighted generalized linear models (e.g., marginal structural models). Models were adjusted for age, BMI, and race, as well as time-varying covariates such as estradiol, stress, leptin, and total energy intake, and accounted for repeated measures (i.e., multiple cycles per woman). Both inflammatory markers and reports of cravings were modeled to account for variation at each visit.

Results

An association between higher inflammatory biomarkers such as hsCRP, GCSF, GMCSF, IL-4, IL-6, RANTES, MIP1B, and increased risk of moderate/severe cravings were identified across the menstrual cycle |all risk ratio>0.8, all CIs range>0.7-0.9|. hsCRP retained statistical significance after false discovery rate correction with chocolate, sweet, and salty cravings, while GCSF, GMCSF, IL-6, and RANTES retained significance with chocolate and sweet cravings only.

Conclusion

The results suggest a potential role of inflammation in food cravings and appetite changes across the menstrual cycle.

Relationship of premenstrual syndrome with postpartum depression and mother-infant bonding

PURPOSE

This study was conducted to investigate the relationship between pre-pregnancy premenstrual syndrome (PMS) history with postpartum depression and mother-infant bonding.

DESIGN AND METHODS

The sample of this descriptive and cross-sectional study included 322 mothers. Data were collected using the Premenstrual Syndrome Scale (PMSS), Edinburgh Postnatal Depression Scale (EPDS), and Brockington Postpartum Bonding Questionnaire (BPBQ).

FINDINGS

There were positive statistically significant correlations between PMSS total and subscale scores and EPDS scores and BPBQ. In addition, there were statistically significant positive correlations between EPDS score scores and BPBQ.

IMPLICATIONS FOR NURSING PRACTICE

Especially by achieving success in PMS management in the pre-pregnancy period, the risk of postpartum depression development can be prevented, and healthy development of mother-infant bonding can be achieved.

Global and regional prevalence and burden for premenstrual syndrome and premenstrual dysphoric disorder: A study protocol for systematic review and meta-analysis

INTRODUCTION

Premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD) are becoming common mental diseases in women impairing daily functioning. Estimation of the epidemiological burden of PMS/PMDD can serve as scientific basis for prevention and management of premenstrual disorders. Herein, we firstly provide a protocol to perform estimation on the prevalence and risk factors for PMS/PMDD in the general population globally and regionally.

METHODS/DESIGN

The PubMed, Web of Science, Chinese National Knowledge Infrastructure, the Cochrane Central Register of Controlled Trials (Cochrane Library), Chinese VIP Information, EMBASE, Wanfang Database, as well as the Chinese Biomedical Literature Database will be queried to find related studies containing information on the prevalence of PMDD (2011-2021). Two independent reviewers will comb the literature and abstract the data characteristics. Disparities will be reconciled via consents. The primary outcome will be the global prevalence. The random-effect model will be employed to pool the assessments. The standard χ2 tests, as well as the I2 statistic will be used to determine heterogeneity. Furthermore, the meta-regression analysis will be employed to estimate the differences in study-level characteristics. All the statistical analyses will be carried out in the software Stata v 15.0 (Stata Corporation, College Station, TX), as well as the R (v R 3.5.1, R Foundation for Statistical Computing, Vienna, Austria) software.

DISCUSSION

Based on existing evidence, our study will offer a high-quality synthesis for global and regional prevalence, burden, and risk factors of PMS/PMDD. Effective strategies will be made for prevention and management of epidemiological burden on the PMS/PMDD, even premenstrual disorders.

ETHICS AND DISSEMINATION

This study does not involve the specific patients, and all research data comes from publicly available professional literature, so an ethics committee is not required to conduct an ethical review and approval of the study.

INPLASY REGISTRATION NUMBER

INPLASY2021120065.

Melatonin for premenstrual syndrome: A potential remedy but not ready

Premenstrual syndrome (PMS), a recurrent and moderate disorder that occurs during the luteal phase of the menstrual cycle and quickly resolves after menstruation, is characterized by somatic and emotional discomfort that can be severe enough to impair daily activities. Current therapeutic drugs for PMS such as selective serotonin reuptake inhibitors are not very satisfying. As a critical pineal hormone, melatonin has increasingly been suggested to modulate PMS symptoms. In this review, we update the latest progress on PMS-induced sleep disturbance, mood changes, and cognitive impairment and provide possible pathways by which melatonin attenuates these symptoms. Moreover, we focus on the role of melatonin in PMS molecular mechanisms. Herein, we show that melatonin can regulate ovarian estrogen and progesterone, of which cyclic fluctuations contribute to PMS pathogenesis. Melatonin also modulates gamma-aminobutyric acid and the brain-derived neurotrophic factor system in PMS. Interpreting the role of melatonin in PMS is not only informative to clarify PMS etiology but also instructive to melatonin and its receptor agonist application to promote female health. As a safe interaction, melatonin treatment can be effective in alleviating symptoms of PMS. However, symptoms such as sleep disturbance, depressive mood, cognitive impairment are not specific and can be easily misdiagnosed. Connections between melatonin receptor, ovarian steroid dysfunction, and PMS are not consistent among past studies. Before final conclusions are drawn, more well-organized and rigorous studies are recommended.

Pubertal development and risk of premenstrual disorders in young adulthood

STUDY QUESTION

Is pubertal timing associated with risk of premenstrual disorders (PMDs) in young adulthood?

SUMMARY ANSWER

Late pubertal development is associated with decreased premenstrual symptom burden and risk of PMDs in young adulthood.

WHAT IS KNOWN ALREADY

PMDs, including premenstrual syndrome and premenstrual dysphoric disorder, may begin during the teenage years. Few risk factors in early life have been identified for PMD development.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study of 6495 female participants during 1996–2013.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We included participants from the Growing Up Today Study (GUTS). Pubertal development was indicated by the timing of menarche, breast and pubic hair growth. Self-reported age at menarche was longitudinally assessed at enrollment (in 1996/2004 for GUTS I/II) and onwards, and classified as early (age ≤ mean − SD, 11.64 years), normative and late menarche (age ≥ mean + SD, 13.95 years). Timing of pubic hair and breast growth were assessed multiple times during follow-up via Tanner scales, and classified into early, normative and late development according to mean ± SD. Using a validated questionnaire based on the Calendar of Premenstrual Experiences, we assessed premenstrual symptoms and identified probable cases of PMDs in 2013. We examined the associations of timing of pubertal development with premenstrual symptom score and disorders using multivariable linear and logistic regressions, respectively.

MAIN RESULTS AND THE ROLE OF CHANCE

In 2013 (mean age = 26), 1001 (15.4%) individuals met criteria for a PMD. An inverse association was found between age at menarche and premenstrual symptom z-score (β −0.05 per year, 95% CI −0.07 to −0.03) and risk of PMDs (odds ratio (OR) 0.93 per year, 95% CI 0.88 to 0.99). Compared to individuals with normative menarche, individuals with late menarche had a lower risk of PMDs (OR 0.73, 95% CI 0.59 to 0.91), while individuals with early menarche had comparable odds (OR 0.98, 95% CI 0.81 to 1.18). Moreover, early growth of pubic hair was associated with increased premenstrual symptoms (z-score β 0.09 per year, 95% CI 0.02 to 0.17) and PMD risk (OR 1.28, 95% CI 1.04 to 1.56), independent of age at menarche. No associations were noted for breast development.

LIMITATIONS, REASONS FOR CAUTION

One major limitation is some misclassification of menarche due to recall. We, however, showed robust association among participants who were premenarcheal at baseline.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings suggest that pubertal timing, particularly timing of menarche, is inversely associated with the risk of developing premenstrual symptoms in young adulthood, and that women with later menarche have significantly lower risk of PMDs. Information on PMDs should be provided to teenage girls and their parents. If these findings are confirmed in independent populations, prevention strategies and early detection programs may be considered for women with early pubertal development.

STUDY FUNDING/COMPETING INTEREST(S)

The work is supported by the National Institutes of Health and Swedish Research Council.

TRIAL REGISTRATION NUMBER

N/A

Association of socio-demographic, dietary and lifestyle factors with Premenstrual Syndrome (PMS) among undergraduate medical students of a tertiary care institute in Ahmedabad, Gujarat

Introduction:

The frequency, as well as the severity of the PMS (Pre-Menstrual Syndrome), varies from female to female based on various socio-demographic, dietary, and lifestyle factors. Nevertheless, the PMS is known to affect day-to-day functioning including interference with school/work productivity, relationships with friends, family, and colleagues. This is especially important for medical students where academic performance is much skillful and demanding.

Methodology:

The inclusion criteria for this cross-sectional survey were female medical students studying in one of the medical colleges of the city, having regular menstrual cycle (in the last three consecutive months) and willing to participate in the research. Students were assigned from each of the four professional years (First, Second, Third, and Final) through random sampling so that the desires sample size was achieved. The study used a pre-designed questionnaire, the “Premenstrual Symptoms Screening Tool (PSST)” (through Google form), that included 14 items assessing premenstrual symptoms of appetite, mood, sleep, anxiety and physical symptoms. It includes functional impairment items in five different domains as well.

Results:

The common symptoms seen in the respondents were anger/irritability (Mild n = 76, 46.3%; Moderate to severe n = 68, 41.4%) followed by physical symptoms which included headaches, joint or muscle pain, breast tenderness, gain in weight and bloating. The commonest functional impairment was college/work efficiency or productivity (n = 79, 48.2%). Alcohol and tobacco consumption had a significant association with PMDD. The type of diet did not have significant statistical association with PMS or PMDD.

Conclusion:

The most common symptoms seen were anger/irritability as well as physical symptoms like headache, breast tenderness etc., Factors like sleep, diet, exercise, yoga, alcohol and smoking were assessed.

Prevalence of premenstrual syndrome and its psychological effects among university students who participate and do not participate in resistance training

ABSTRACT The study aimed to investigate the prevalence and effects of premenstrual syndrome (PMS) on the psychological factors of university students who do and do not participate in resistance training. The initial sample consisted of 81 participants, and the prevalence of PMS was 64.2%. Forty women diagnosed with PMS were divided into two groups: women who participated in (GP) and did not participate in (GNP) resistance training. The intergroup comparison showed significant differences (with higher scores in the GNP) in the items: difficulty concentrating, lack of energy, and feeling under pressure, and they reported a greater influence of the symptoms on their family relationships. It is concluded that women who participate in resistance training have reduced indicators of some psychological symptoms of PMS.

The effects of acupressure and yoga for coping with premenstrual syndromes on premenstrual symptoms and quality of life

OBJECTIVE

This study aims to identify the effects of acupressure and yoga for coping with premenstrual syndromes (PMS) on the premenstrual symptoms and quality of life.

METHODS

This study adopted a randomized intervention design with a pretest-posttest control group. The sample consisted of 155 students with PMS complaints (50 in yoga, 51 in acupressure, and 54 in control group). The students in the intervention groups did yoga and received acupressure throughout 12 weeks.

RESULTS

It was found that the Premenstrual Syndrome Scale posttest mean score of the students was lower, and the physical health, psychological health, and environment sub-scale mean scores of the World Health Organization Quality of Life Questionnaire were higher in the yoga group in comparison to the other groups (p < 0.05).

CONCLUSION

Yoga was found to be a more effective non-pharmacological method for coping with premenstrual symptoms.

Are premenstrual syndrome and dysmenorrhea related to the personality structure of women? A descriptive relation-seeker type study

PURPOSE

This study was conducted to define the relationship of experiencing premenstrual syndrome (PMS) and dysmenorrhea with the personality structure of women.

DESIGN AND METHODS

The sample of this descriptive relation-seeker-type study comprised 353 women. Data were collected using the PMS Scale, Quick Big Five Personality Test, and The Questionnaire Form between 1 April and 31 August 2019 in a city in the Mediterranean region in Turkey.

FINDINGS

There was a weak negative-biased correlation between PMS and extraversion, a very weak negative-biased correlation between PMS and conscientiousness, a moderate negative-biased correlation between PMS and neuroticism, and a very weak positive-biased significant correlation between PMS and openness (P < .05).

PRACTICE IMPLICATIONS

These data suggest that women who are introverted, have weak self-confidence, tend to have negative feelings such as anxiety, depression, and anger, and have weak coping skills are at risk for experiencing PMS.

Effect of exercise on symptoms of premenstrual syndrome in low and middle-income countries: a protocol for systematic review and meta-analysis

INTRODUCTION

Premenstrual syndrome (PMS) has the potential to affect the quality of life adversely. Published guidelines recommend the use of exercise as part of the first-line management interventions for PMS. However, the published evidence related to the effectiveness of physical activity and PMS is inconclusive. This review will assess the effectiveness of exercise-based interventions in reducing PMS in women screened or diagnosed with PMS in low and middle-income countries, where the prevalence of PMS is high.

METHODS AND ANALYSIS

Electronic databases will be researched, including Embase, Cochrane Central Register of Controlled Trials, MEDLINE, PsycINFO, Web of Science, ClinicalTrials.gov and Google Scholar. All the studies published until March 2020 will be included. A standardised data extraction form will be used adapted from the Cochrane Handbook of Systematic Reviews of Interventions. Included articles will be assessed using the risk of bias tools based on study design. Data will be analysed using Review Manager V.5.3. The inverse-variance random-effects method will be used to report the standardised mean difference. A meta-analysis will be used only if studies are sufficiently homogenous. A narrative synthesis will be undertaken when studies are heterogeneous. Methodological heterogeneity between studies will be evaluated by considering the study types. Statistical heterogeneity will be tested using the I² test. Subgroup analyses may be performed only for the primary outcome in case of sufficient studies. Sensitivity analysis will be conducted to assess the impact of intervention excluding studies without randomisation and studies with a high risk of bias. Funnel plots will be used to assess the potential reporting bias and small-study effects only when there are more than 10 studies included in the meta-analysis.

ETHICS AND DISSEMINATION

This study does not require ethical approval, as the review is entirely based on published studies. The results will be published and/or will be presented at a pertinent conference.

PROSPERO REGISTRATION NUMBER

CRD42020163377.