Reinforced pain catastrophizing during menstrual phase among women with primary dysmenorrhea is mediated by cerebral blood flow in the medial prefrontal cortex.

Pain catastrophizing is a prominent psychological factor that is strongly correlated with pain. Although the complex properties of pain catastrophizing vary across different pain phases, the contribution of chronic pain to its progression from a general trait to a higher state remains unclear. This study aimed to examine the neural mechanisms and degree to which pain catastrophizing is reinforced in the context of primary dysmenorrhea (PDM), one of the most prevalent gynaecological complaints experienced by women of reproductive age. Altogether, 29 women with moderate-to-severe PDM were included in this study. Arterial spin labelling was used to quantify the cerebral blood flow (CBF) in each participant in both the pain-free and painful phases. The pain catastrophizing scale (PCS) was completed in two phases, and the Short-Form McGill Pain Questionnaire was completed in the painful phase. Compared with pain catastrophizing in the pain-free phase (PCSpf), pain catastrophizing in the painful phase (PCSp) is higher and positively correlated with the composite factor of menstrual pain. CBF analysis indicated that the PCSp is positively associated with CBF in the frontal cortex, hippocampus and amygdala. The reinforcement of pain catastrophizing correlates with CBF in the prefrontal cortex. Specifically, the medial prefrontal cortex, which correlates with pain state, plays a crucial role in mediating the reinforcing effect of pain in the PCSp. These results promote the mechanical comprehension of pain catastrophizing management in individuals with chronic pain.

Dietary pattern and menstrual disorders among female university students.

OBJECTIVES: Assessment of the relationship between dietary patterns and menstrual disorders among female medical and paramedical students at Beni-Suef University, Egypt. METHODS: Beni-Suef University conducted a cross-sectional analytical questionnaire-based study. Three hundred fifty two female medical and paramedical students agreed to participate in the study. The collected data about demographics, physical activity, menstrual history, and dietary assessment were transferred to SPSS version 26 for statistical analysis. A p value ≤0.05 was considered statistically significant. RESULTS: The prevalence of irregular cycles, heavy blood flow, severe dysmenorrhea, and premenstrual syndrome (PMS) was found to be (21.9 %), (13.1 %), (35.5 %), and (68.9 %), respectively. Poor adherence to the Mediterranean diet (40.1 %) and physical activity (69.9 %) was present. Females with irregular cycles (p=0.472), heavy menstrual blood flow (p=0.007), and severe dysmenorrhea (p=0.029) reported lower adherence to the Mediterranean diet. Mothers' educational level (p=0.034), family income (p=0.005), and family size (p=0.009) were significantly associated with dietary adherence. CONCLUSIONS: Poor adherence to regular physical activity and the Mediterranean diet is highly prevalent in our research and is highly associated with menstruation disorders. So, it is critical to support health education programs emphasizing healthy dietary habits and regular physical activity to improve menstrual health and women's quality of life.

Validation of the Working Ability, Location, Intensity, Days of Pain and Dysmenorrhea (WaLIDD) Scale in Arabic-Speaking Young Female Adults.

Background: Dysmenorrhea, characterized by painful menstrual cramps, significantly impacts the well-being of women globally. Despite its prevalence and adverse effects, dysmenorrhea is often underdiagnosed and inadequately treated. This study aims to validate the Arabic version of the Working ability, Location, Intensity, Days of pain, and Dysmenorrhea (WaLIDD) scale among Lebanese female university students aged 18-45. Methods: This cross-sectional study, involving 729 participants, utilized a translated WaLIDD scale and the Depression, Anxiety, and Stress Scales (DASS-8). Results: Confirmatory Factor Analysis (CFA) confirmed the one-factor structure of the WaLIDD scale, demonstrating excellent fit indices, with good internal reliability. Concurrent validity analysis revealed significant associations between higher WaLIDD scores and elevated levels of depression, anxiety, and stress. The prevalence of dysmenorrhea in the study was estimated at 7.3%. Conclusion: The study underscores the importance of the WaLIDD scale as a reliable and valid tool for assessing dysmenorrhea among Arabic-speaking populations. The successful validation of the Arabic version facilitates its application in Lebanon and potentially other Arab regions, providing a universal tool to predict and assess dysmenorrhea and its impact. Further research is encouraged to explore the scale's applicability in clinical settings and tailor interventions for improved women's well-being.

Association Between Shift Work and Clean Room Environment on Self-reported Premenstrual Symptoms and Menstrual Pain in Taiwan.

Background: Limited research has delved into the effects of work characteristics on premenstrual symptoms (PMS) in women, which can influence work performance and overlook potential hazards for women in their work environments. This study aimed to investigate the impact of shift work and working in a clean room on premenstrual symptoms, menstrual status, and menstrual pain among employed females in an electronics manufacturer. Methods: A retrospective cohort study was conducted on menstruating female employees between August and December 2014, aged 18-55, who received regular employee health checks. Questionnaires were designed to collect information on demographics, personal lifestyle, menstrual status, menstrual pain scores, and self-reported premenstrual symptoms. Results: Among 7,193 participants, 18.6% reported moderate to severe menstrual pain affecting their work. Female workers who reported shift work showed an increased prevalence of moderate to severe premenstrual symptoms, including fatigue (RR = 1.20), somatic discomforts (RR = 1.04), diarrhea (RR = 1.04), and tension (RR = 1.05). Additionally, shift work was associated with an elevated risk of experiencing a moderate or significant impact of menstrual pain on work (RR = 1.03), menstrual irregularity (RR = 1.30), and high menstrual pain (RR = 1.23). Working in a clean room was associated with an increased risk of high menstrual pain (RR = 1.13). Subjects working shifts in a clean room had the highest pain scores compared to the other groups. Conclusion: This study underscores the association of work-related factors on PMS in female employees. Our findings contribute to a better understanding of premenstrual symptoms in female workers with different work characteristics, emphasizing the potential hazards of work-related factors on female employees.

Effect of Sanyinjiao (Spleen-6) Acupoint for Pain Management in Primary Dysmenorrhea: An Updated Systematic Review and Meta-Analysis.

Objectives: Available literature highlights the effectiveness of Acupuncture or Acupressure on the Spleen 6 acupoint (Sanyinjiao or SP-6) for pain management in primary dysmenorrhea (PD). The objective of the current systematic review and meta-analysis is to provide an updated assessment of available randomized and non-randomized controlled trials and to compare the effectiveness of acupressure and acupuncture stimulation of Sanyinjiao among patients with PD. Methods: We conducted a comprehensive literature search on various electronic databases including Embase, PubMed, and the Cochrane Library from January 1990 to March 2023 to identify the comparative studies (randomized and non-randomized controlled trials) that assessed the effects of acupressure or acupuncture on the Sanyinjiao acupoint in patients with PD. We assessed the studies' risk of bias in accordance with the Cochrane Handbook for Systematic Reviews of Interventions, and certainty of evidence using the Grading of Recommendations Assessment. Subsequently, a fixed-effects meta-analysis was performed using the Der-Simonian and Laird method to combine intervention effects from the included studies. The primary outcome of interest was a reduction in pain. Results: We included 19 studies (9 acupressure and 10 acupuncture) with 1171 PD patients. This meta-analysis showed a significant (Standardized Mean Difference, SMD: -0.29, 95% confidence interval -0.41 to -0.17, p < 0.001) reduction in pain, for both acupressure and acupuncture at Sanyinjiao acupoint with considerable heterogeneity. Acupressure was found to be more effective than acupuncture stimulation in reducing pain associated with PD (SMD: -0.52, 95% confidence interval -0.71 to -0.33, p < 0.001). Conclusion: The findings of this updated systematic review and meta-analysis suggest that both acupuncture and acupressure on Sanyinjiao acupoint could effectively reduce pain associated with PD. Acupressure stimulation, in particular, was found to be more effective than acupuncture stimulation of the acupoint in reducing pain associated with PD.

Benefits of core stability exercise and relaxation technique for primary dysmenorrhea in an unmarried girl: A case report.

Primary dysmenorrhea denotes the onset of recurrent lower abdominal pain and uterine contractions throughout the bleeding phase of menstruation in the absence of any underlying pelvic pathology. Core stability exercise is considered a beneficial exercise program for managing several health problems. Various relaxation techniques can be used in womanhood with primary dysmenorrhea for relief of pain and improving their quality of life (QOL). The aim of this study was to learn and understand the benefits of core stabilization exercise along with relaxation techniques for primary dysmenorrhea in an unmarried girl. This single-case study was planned to analyze the effect of core stability exercise along with relaxation techniques in the management of primary dysmenorrhea symptoms. Relaxation exercises along with core stability exercises were given to subjectswith primary dysmenorrhea for 20 sessions of 30 minutes spanned for 5 weeks, four sessions a week. Along with the demographic profile, pre- and post -intervention value of pain in the visual analog scale (VAS) and Working Ability, Location, Intensity, Days of Pain, Dysmenorrhea (WaLIDD) score was obtained, recorded, and analyzed. This single-case study results showed significant improvement in the outcome of pain in the VAS and WaLIDD score after the intervention of core stability exercise along with relaxation exercise for the primary dysmenorrhea patients. Pre- and post-intervention of core stability exercise along with Mitchell's relaxation exercises, measurements of VAS, and dysmenorrhea severity in WaLIDD scores revealed an effective reduction in pain and severity using core stability training and relaxation training in an unmarried girl diagnosed with primary dysmenorrhea.

Susceptibility to Infection and Impact of COVID-19 Vaccines on Symptoms of Women with Endometriosis: A Systematic Review and Meta-Analysis of Available Evidence.

Women with endometriosis were deemed more prone to COVID-19 infection in some reports. Considering that endometriosis-related aberrant immune response, understanding how COVID-19 vaccination influences its clinical status is crucial. The aim of this meta-analysis was the evaluate the susceptibility to COVID-19 infection and modifications of symptoms following COVID-19 vaccination in women with endometriosis. Electronic searches on EMBASE, MEDLINE, Scopus, Cochrane at CENTRAL, Scielo.br, LILACS and other databases were searched from inception to March 2024. Studies were eligible if they analyzed the incidence of infection in endometriosis women or the changes in symptoms after two doses of COVID-19 vaccine and had a control group. Four studies (2249 women) were included. No increased susceptibility to COVID-19 infection due to presence or absence of endometriosis was retrievable (risk ratio (RR) 1.42 [95% CI 0.88 to 2.27]; I2 = 33%). Patients with endometriosis did not experience an overall worsening of symptomatology relative to controls (RR 1.58 [95% CI 0.67 to 3.75]; I2 = 94%). An increase in the risk of dysmenorrhea worsening was noted (RR 1.88 [95% CI 1.11 to 3.17]; I2 = 63%). No other differences regarding menstrual flow (RR 1.25 [95% CI 0.70 to 2.23]; I2 = 78%), intermenstrual bleeding (RR 1.14 [95% CI 0.83 to 1.56]; I2 = 39%) and pelvic pain (RR 2.55 [95% CI 0.65 to 10.05]; I2 = 80%) compared to controls was retrievable. Therefore, mRNA vaccines do not seem to lead to worsening of symptomatology in endometriotic women. However, a slight temporary increase in dysmenorrhea may be present. Moreover, endometriosis does not seem to increase the risk of contracting COVID-19.

DYSMENORRHEA-RELATED IMPACT ON FUNCTIONING SCALE (DIFS): DEVELOPMENT AND MEASUREMENT PROPERTIES FOR CISGENDER WOMEN AND TRANSGENDER MEN.

OBJECTIVES: To develop the Dysmenorrhea-related Impact on Functioning Scale (DIFS) to assess the impact of dysmenorrhea on functioning in cisgender women and transgender men and to evaluate its measurement properties. METHODS: Mixed and online design study conducted with adolescents and adult cisgender women and transgender men with dysmenorrhea. We developed the DIFS based on the International Classification of Functioning, Disability and Health. Content validity was assessed with experts and people with dysmenorrhea. Item Response Theory developed the DIFS total score. Structural validity was assessed by exploratory and confirmatory factor analysis, and internal consistency by Cronbach's α and McDonald's Ω. Construct validity and test-retest reliability were assessed by correlation between DIFS and WHODAS, and intraclass correlation coefficient (ICC), respectively. Measurement error was also assessed. RESULTS: 3335 people participated in the study. The DIFS is a 15-item instrument divided into "Bodily Functions" and "Daily Activities and Social Participation" sections, and "Functioning" as a general factor. Internal consistency (α and Ω > 0.7) and test-retest reliability (ICC > 0.9) were adequate. No systematic error was found. Correlation was positive and strong between WHODAS and "Functioning" (r = 0.62, p ≤ 0.05). For the DIFS total score, higher scores indicate a greater impact of dysmenorrhea on functioning, and 44 points is the cut-off point for classifying the person with a significant impact of dysmenorrhea on functioning. CONCLUSIONS: DIFS showed excellent measurement properties for assessing the impact of dysmenorrhea on functioning for cisgender women and transgender men.

Abnormal Topological Organization of Human Brain Connectome in Primary Dysmenorrhea Patients Using Graph Theoretical Analysis.

Background: Accumulating studies have revealed altered brain function and structure in regions linked to sensory, pain and emotion in individuals with primary dysmenorrhea (PD). However, the changes in the topological properties of the brain's functional connectome in patients with PD experiencing chronic pain remain poorly understood. Purpose: Our study aimed to explore the mechanism of functional brain network impairment in individuals withPD through a graph-theoretic analysis. Material and Methods: This study was a randomized controlled trial that included individuals with PD and healthy controls (HC) from June 2021 to June 2022. The experiment took place in the magnetic resonance imaging facility at Jiangxi Provincial People's Hospital. Static MRI scans were conducted on 23 female patients with PD and 23 healthy female controls. A two-sample t-test was conducted to compare the global and nodal indices between the two groups, while the Network-Based Statistics (NBS) method was utilized to explore the functional connectivity alterations between the groups. Results: In the global index, The PD group exhibited decreased Sigma (p = 0.0432) and Gamma (p = 0.0470) compared to the HC group among the small-world network properties.(p<0.05) In the nodal index, the PD group displayed reduced betweenness centrality and increased degree centrality in the default mode network (DMN), along with decreased nodal efficiency and increased degree centrality in the visual network (VN). (P < 0.05, Bonferroni-corrected) Furthermore, in the connection analysis, PD patients showed altered functional connectivity in the basal ganglia network (BGN), VN, and DMN.(NBS corrected). Conclusion: Our results indicate that individuals with PD showed abnormal brain network efficiency and abnormal connection within DMN, VN and BGN related to pain matrix. These findings have important references for understanding the neural mechanism of pain in PD.

Submucosal cystic adenomyosis: a report of five cases and review of the literature.

AIM: To investigate the clinical characteristics, diagnosis, and clinical treatment of submucosal cystic adenomyosis. METHODS: The clinical data of five cases of patients with submucosal cystic adenomyosis in our hospital from January 2020 to June 2023 were retrospectively analyzed. RESULTS: The average age of the patients was 37.8 ± 4.5 years old, three of them experienced prolonged menstruation and heavy menstrual bleeding. All patients had a history of abnormal uterine bleeding and mild to moderate dysmenorrhea, with a VAS score of 2.8 ± 1.6. The average Carbohydrate antigen 125 (CA125) value was 29.9 ± 23.6U/ml. Two out of the five patients (40%) had CA125 values above the upper limit of normal. The nodules had a diameter of 3.2 ± 1.3 cm and a cavity size of 1.3 ± 0.7 cm. Color ultrasound revealed hypo or iso or anechoic echoic cysts, and blood flow signals were detected. The magnetic resonance imaging (MRI) findings varied among each patient. All the patients underwent hysteroscopy and resection of uterine cavity-occupying lesions, and no recurrence was observed. CONCLUSIONS: The clinical features of submucosal cystic adenomyosis include abnormal uterine bleeding and menstrual changes, and the degree of dysmenorrhea is generally not severe. The diagnostic utility of CA125 in submucosal cystic adenomyosis may be limited. The three-dimensional ultrasound and MRI are valuable preoperative examination methods currently. Hysteroscopy can not only diagnose submucosal cystic adenomyosis, but also treat it, and preserve the fertility function of the patient.

MRI for endometriosis in adolescent patients.

Endometriosis, a chronic condition that often starts in adolescence, can have a significant impact on quality of life due to symptoms of dysmenorrhea and pelvic pain. Although laparoscopy with direct visualization and pathologic correlation is the reference standard for the diagnosis of endometriosis, some authors have called for a greater emphasis on clinical diagnosis - including imaging. Magnetic resonance imaging (MRI) provides highly reproducible, large field of view, multiplanar, and multiparametric imaging of pelvic endometriosis and is well tolerated in adolescent patients. As such, pediatric radiologists need to be familiar with the manifestations of endometriosis on MRI and how these findings may differ from those seen in adult populations.

Associations between soft drinks intake and primary dysmenorrhea among Chinese undergraduate female students.

Primary dysmenorrhea (PD) is a common global health concern. However, limited studies explored the association between soft drinks intake and PD among female undergraduates in China. To determine the association between soft drinks (carbonated soft drinks, etc.) as well coffee intake and the incidence/severity of PD among female undergraduates in China. We performed a cross-sectional study among 1809 female undergraduates in China from September 29, 2020 to October 22, 2020. The demographic information and menstrual information of the participants were collected by a self-administrated questionnaire. Chi-square test, ANOVA test, and logistic regression test were used to investigate the association between soft drinks intake and the incidence/severity of PD. We also conducted stratification analysis among different locations (rural or urban). The prevalence of PD was 47.1% (n = 852). There were 221 (25.9%) participants suffered from severe pain. In the participants with PD, the OR of carbonated soft drinks intake was 1.244 (95% CI 1.010-1.533). Among the participants with PD from rural areas, the OR of carbonated soft drinks intake was 1.402 (95% CI 1.045-1.881), compared with the non-carbonated soft drink group. In the participants with moderate and severe PD, the OR of coffee intake was 0.451 (95% CI 0.228-0.892), compared with the non-coffee-drinking group. There was a significant association between carbonated soft drinks intake frequency and the severity of PD (P < 0.05). Our study showed that carbonated soft drinks intake is a risk factor for PD, especially in participants from rural areas. Coffee intake is a protective factor for the severity of PD. Periodical awareness programs about adverse effects of excessive soft drink consumption should be introduced to reduce the prevalence and exacerbation of PD. Coffee intake might be helpful to relieve the severity of PD.

Traditional Chinese medicine interventions based on meridian theory for pain relief in patients with primary dysmenorrhea: a systematic review and network meta-analysis.

Objective: To determine the comparative effects and safety of traditional Chinese medicine (TCM) interventions based on meridian theory for pain relief in patients with primary dysmenorrhea (PD). Methods: This is a systematic review with network meta-analysis. Randomized controlled trials (RCTs) comparing meridian-based TCM interventions with waitlist, placebo, western medicine, and conventional therapies for PD pain. A SUCRA was used to estimate the probability ranking for the effects of interventions. Results: 57 RCTs involving 3,903 participants and 15interventions were included. Thirty-two RCTs were rated as low risk of bias. A network diagram was drawn with 105 pairs of comparisons. Compared with NSAIDs and waitlist, significantly better effects were found in acupressure [SMD = -1.51, 95%CI (-2.91, -0.12)/SMD = -2.31, 95%CI (-4.61, -0.02)], warm needling [SMD = -1.43, 95%CI (-2.68, -0.18)/SMD = -2.23, 95%CI (-4.43, -0.03)], moxibustion [SMD = -1.21, 95%CI (-1.85, -0.57)/SMD = -2.10, 95%CI (-3.95, -0.07)], and acupuncture [SMD = -1.09, 95%CI (-1.62, -0.55)/SMD = -1.89, 95%CI (-3.67, -0.11)]. No adverse events were detected. Conclusion: For PD pain, the effects of acupressure, acupuncture, warm needling, and moxibustion were superior to those of NSAIDs and waitlist. Oral contraceptive pill, electro-acupuncture, acupressure, and warm needling demonstrated higher probabilities of being better interventions. More high-quality clinical trials are needed to provide more robust evidence of this network. Systematic review registration: PROSPERO CRD42022373312.

Integrated metabolomics and lipidomics investigation of the mechanism of Danggui Sini Decoction on improving lipid homeostasis in primary dysmenorrhea.

BACKGROUND: Danggui Sini Decoction (DGSND) is a classic prescription for treating primary dysmenorrhea (PD), while, the ameliorating effects of DGSND on PD and its mechanisms are not yet fully understood. PURPOSE: The present study is devoted to investigate the protective effect of DGSND against PD and the possible mechanism from the perspective of metabolomics as well as lipidomics. METHODS: DGSND was characterized by UPLC-Q-TOF/MS. The PD rat model was induced by estradiol benzoate and oxytocin, and traditional pharmacology, including writhing times, latency time, biochemical index, organ index, and histopathology were performed to evaluated the efficacy of DGSND on PD. Urine metabolomics strategy combined with functional analysis was adopted to delineate the therapeutic effect of DGSND on PD rats and anchor the crucial pathway, and lipidomics analysis was further performed with the uterine tissue as the research object to elucidate the protective mechanism of DGSND from the perspective of lipid homeostasis. Finally, western blot analysis was used to validate the expression of key metabolic enzymes in lipid metabolism. RESULTS: DGSND was effective in ameliorating writhing times, latency time, the value of prostaglandin F2α (PGF2α)/PGE2, uterus index, and morphological changes of PD rats. Metabolic signature of PD rats was primarily characterized by the disturbance of steroid hormone metabolism, amino acid metabolism, and lipid metabolism. Functional analysis revealed the urine biomarkers of PD were most related with lipid abnormality. Further lipidomics analysis indicated DGSND exerted anti-PD effects by remodeling lipid homeostasis, which might be due to the significant correlations between different kinds of lipids, especially the extremely high correlation of phosphatidylethanolamine, phosphatidylcholine, and fatty acids. Moreover, the key metabolic enzymes expression of CK, PLA2, LPCAT3, COX-2, and 5-LOX can be greatly downregulated by DGSND. CONCLUSION: Our findings demonstrated a novel protective mechanism of DGSND against PD by regulating lipid homeostasis.

Wenjing decoction: Mechanism in the treatment of dysmenorrhea with blood stasis syndrome through network pharmacology and experimental verification.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese Medicine (TCM) formula Wenjing Decoction (WJD) longstanding efficacy in enhancing blood circulation, resolving blood stasis, and mitigating dysmenorrhea symptoms. Despite its prevalent application, the specific mechanism underlying effect of WJD remains elusive. OBJECTIVE: The purpose of this study is to examine the material basis of Wenjing Decoction and explore the effect of WJD on rat models of dysmenorrhea with blood stasis syndrome and elucidate its mechanism. METHODS: In this study, we initially identified the chemical constituents of WJD using liquid chromatography-mass spectrometry (LC-MS). Subsequently, we employed network pharmacology to predict the mechanism of WJD in treating acute blood stasis dysmenorrhea. To further investigate the role of WJD, we established a rat model of acute blood stasis. We monitored changes in blood coagulation indexes, IL-6, TNF-α, NO, and COX-2 in rats before and after administration to confirm the successful establishment of the rat model and evaluate the therapeutic effect of WJD on dysmenorrhea and acute blood stasis. Finally, real-time fluorescence quantitative PCR (qPCR) and Western blot (WB) were utilized to investigate its mechanism. RESULTS: Through LC-MS analysis, 69 chemical substances were identified in WJD. Network pharmacology study revealed that the mechanism of WJD in treating BSS may be associated with the PI3K/AKT/NF-κB pathway. Following administration, the WJD group showed gradual recovery of physical signs and coagulation index to a healthy level. Additionally, the levels of IL-6, TNF-α, and COX-2 decreased in a dose-dependent manner, whereas NO levels increased. Results from QPCR and WB detection indicated increased expression levels of p-PI3K, p-AKT, Bcl-2, and eNOS, and decreased expression levels of Bax, NFκBp65, ICAM1, and VCAM1. CONCLUSION: The results show that WJD significantly improves the characterization, dysmenorrhea index, and coagulation-related factors in BSS rats. Through network pharmacological prediction, real-time fluorescence quantitative PCR, and Western blot analysis, it is postulated that the beneficial effects of WJD on dysmenorrhea may be linked to the PI3K/AKT/NF-κB signaling pathway. These findings offer a theoretical foundation for the advancement and utilization of WJD.

Reward system neurodynamics during menstrual pain modulated by COMT Val158Met polymorphisms.

Introduction: Primary dysmenorrhea (PDM), characterized by cyclic pain, may involve pain modulation within the reward system (RS). The Catechol-O-methyltransferase (COMT) Val158Met polymorphism, which significantly influences dopamine activity, is linked to the regulation of both acute and chronic pain. This study examines the differential neurodynamic modulation in the RS associated with COMT Val158Met polymorphisms during menstrual pain among PDM subjects. Method: Ninety-one PDM subjects underwent resting-state fMRI during menstruation and were genotyped for COMT Val158Met polymorphisms. The amplitude of low-frequency fluctuation (ALFF) and functional connectivity (FC) analyses were used to assess the RS response. Psychological evaluations included the McGill Pain Questionnaire, Pain Catastrophizing Scale, Beck Anxiety Inventory, and Beck Depression Inventory. Result: Val/Val homozygotes (n = 50) and Met carriers (n = 41) showed no significant differences in McGill Pain Questionnaire, Beck Anxiety Inventory, and Beck Depression Inventory. However, Met carriers exhibited lower scores on the Pain Catastrophizing Scale. Distinct FC patterns was observed between Val/Val homozygotes and Met carriers, specifically between the nucleus accumbens (NAc) and prefrontal cortex, NAc and inferior parietal lobe, ventral tegmental area (VTA) and prefrontal cortex, VTA and precentral gyrus, and VTA and superior parietal lobe. Only Met carriers showed significant correlations between ALFF and FC values of the NAc and VTA with pain-related metrics (McGill Pain Questionnaire and Pain Catastrophizing Scale scores). NAc ALFF and NAc-prefrontal cortex FC values positively correlated with pain-related metrics, while VTA ALFF and VTA-prefrontal cortex and VTA-superior parietal lobe FC values negatively correlated with pain-related metrics. Discussion: This study reveals that the COMT Val158Met polymorphism results in genotype-specific functional changes in the brain's RS during menstrual pain. In Met carriers, engagement of these regions is potentially linked to motivational reward-seeking and top-down modulation. This polymorphism likely influences the RS's responses, significantly contributing to individual differences in pain regulation.

Associations between plasma metals and hemoglobin in female college students with dysmenorrhea.

Background: Hemoglobin (HGB) was the most important factors which could cause dysmenorrhea in women. Metals exposure and hemoglobin level in dysmenorrhea female was unclear. We aimed to explore the associations of multi-metal exposure and HGB level in female college students with dysmenorrhea. Methods: 253 female students who had dysmenorrhea was included in our study. The Last Absolute Shrinkage and Selection Operator (LASSO) regression, generalized linear model (GLM), and Bayesian Kernel Machine Regression (BKMR) models were used to explore the associations of multi-metal exposure and HGB levels in female college students with dysmenorrhea. Results: GLM results showed that plasma Fe, Ni and Rb was positively associated with HGB and plasma Co was negatively associated with HGB. In menarche age ≤13 years old group, plasma Co and Rb only was negatively and positively associated with HGB level, respectively, and plasma Ni had positive association with HGB level in menarche age >13 years old group. BKMR results showed the reverse U-shaped relationship between the five metals mixture (Co, Fe, Ni, Cu and Rb) and HGB levels in overall and menarche age ≤13 years old group. However, there were positive association between the five metals mixture and HGB levels in menarche age >13 years old group. Conclusion: Our present study revealed that metals (Fe, Ni, Co, Rb, Cu) mixture exposure could effect HGB levels in female college students with dysmenorrhea. And the relationships were different during different menarche age in female college students.

Transcutaneous Tibial Nerve Stimulation for Pain Management in Women with Primary Dysmenorrhea: A Randomized Clinical Trial.

Primary dysmenorrhea is considered one of the main causes of pelvic pain during a woman's childbearing years, resulting in poor quality of life. The objective was to evaluate the effectiveness of transcutaneous tibial nerve stimulation (TTNS) in painful symptomatology improvement and non-steroidal anti-inflammatory drug (NSAID) intake reduction in women with primary dysmenorrhea (PD) compared with a control group in the short, medium, and long terms. A single-blind, controlled clinical trial was developed. Participants were randomized to the experimental (TTNS) and control group (sham TTNS). Both groups received 12-weekly 30-min sessions with a NeuroTracTM PelviTone electrostimulation device. The intensity and severity of pain and non-steroidal anti-inflammatory drug (NSAID) intake were evaluated in the short-term (after treatment), medium-term (1-3 months), and long-term (6 months). A total of 61 participants were randomized, with a split of 31 (experimental group) and 30 (control group), but 55 participants completed the study and were analyzed. Statistically significant differences between both groups in the maximum pain intensity decrease (F = 4.88, p = 0.0043) measured with the visual analogue scale, as well as NSAID intake decrease (F = 4.68, p = 0.011) and days of their ingestion (F = 4.57, p = 0.012) occurred in the short term. Furthermore, significant decreases in the total number of NSAIDs ingested during the cycle (F = 3.82, p = 0.011) and the number of days on which patients ingested NSAIDs (F = 3.59, p = 0.015) in the medium-long term occurred. TTNS could be an effective and safe strategy to reduce pain caused by PD, which could reduce or complement the use of pharmacological techniques and other more invasive methods.

Neural adaptation of the reward system in primary dysmenorrhea.

Introduction: The brain's reward system (RS) reacts differently to pain and its alleviation. This study examined the correlation between RS activity and behavior during both painful and pain-free periods in individuals with primary dysmenorrhea (PDM) to elucidate their varying responses throughout the menstrual cycle. Methods: Ninety-two individuals with PDM and 90 control participants underwent resting-state functional magnetic resonance imaging (rsfMRI) scans during their menstrual and peri-ovulatory phases. Regional homogeneity (ReHo) and amplitude of low-frequency fluctuation (ALFF) analyses were used to evaluate RS responses. Psychological evaluations were conducted using the McGill Pain Questionnaire and the Pain Catastrophizing Scale. Results: ReHo analysis showed higher values in the left putamen and right amygdala of the PDM group during the peri-ovulatory phase compared to the menstrual phase. ALFF analysis revealed lower values in the putamen of the PDM group compared to controls, regardless of phase. ReHo and ALFF values in the putamen, amygdala, and nucleus accumbens were positively correlated with pain scales during menstruation, while ALFF values in the ventral tegmental area inversely correlated with pain intensity. Those with severe PDM (pain intensity ≥7) displayed distinct amygdala ALFF patterns between pain and pain-free phases. PDM participants also had lower ReHo values in the left insula during menstruation, with no direct correlation to pain compared to controls. Discussion: Our study highlights the pivotal role of the RS in dysmenorrhea management, exhibiting varied responses between menstrual discomfort and non-painful periods among individuals with PDM. During menstruation, the RS triggers mechanisms for pain avoidance and cognitive coping strategies, while it transitions to processing rewards during the peri-ovulatory phase. This demonstrates the flexibility of the RS in adapting to the recurring pain experienced by those with PDM.

The effect of dysmenorrhea severity and interference on reactions to experimentally-induced pain.

Introduction: Dysmenorrhea is associated with increased risk of chronic pain and hyperalgesia. Menstruating individuals with dysmenorrhea are more likely to have elevated pain reactivity when experiencing experimental pain, than those without. However, no study has examined intragroup differences in reactions to experimentally induced pain for individuals with dysmenorrhea. The main aim of this study was to examine the relative roles of dysmenorrhea severity and interference in the experience of experimentally-induced pain. Methods: Participants were 120 menstruating individuals involved in a larger research study examining the influence of expectations on experimentally-induced pain. As part of the study, participants completed an online questionnaire regarding demographic and menstrual information and participated in a cold pressor task. Participants were randomized into four groups based on the manipulation of two independent variables: (1) high vs. low expectations about pain severity (pain-expectations); (2) and high vs. low expectations about one's pain tolerance (self-expectations). Participants verbally rated their pain severity throughout the cold pressor task using a 0-10 scale. Regression analyses were conducted examining the relationships between dysmenorrhea experience (i.e., average severity and interference) and cold pressor data [pain severity ratings and pain tolerance (i.e., total time in the cold pressor)], controlling for the manipulated expectations and age. Then, moderation analyses were conducted examining expectation group differences. Results: When controlling for manipulated expectations and age, dysmenorrhea severity significantly predicted initial pain severity rating (p = 0.022) but did not predict final pain severity rating (p = 0.263) or pain tolerance (p = 0.120). Dysmenorrhea interference did not predict initial pain severity rating (p = 0.106), final pain severity rating (p = 0.134), or pain tolerance (p = 0.360). A moderation analysis indicated that the relationship between dysmenorrhea severity and initial pain severity rating was not moderated by pain-expectations, χ 2(1) = 0.412, p = 0.521. Discussion: During an experimentally-induced pain task, dysmenorrhea severity but not interference predicted initial pain severity rating, such that higher levels of dysmenorrhea severity predicted greater initial pain severity rating. This suggests individuals with more severe dysmenorrhea pain may experience greater initial sensitivity to pain and be at risk for increased sensitivity to acute pain and potentially the development of chronic pain.