Cyclical pain in women: the influence of hormonal fluctuations and pain modulation mechanisms

• Published in: PAIN RESEARCH Vol. 40; no. 1; pp. 22 - 30
• Main Authors: Dokita, Ayaka, Matsubara, Takako, Hattori, Takafumi, Ohga, Satoshi, Shimo, Kazuhiro
• Format: Journal Article
• Language: English
• Published: JAPANESE ASSOCIATION FOR STUDY OF PAIN 13.02.2025; 一般社団法人 日本疼痛学会
• Subjects: Affect; Autonomic reactions; Cyclical pain; Hormonal fluctuations; Neural pain modulation
• ISSN: 0915-8588; 2187-4697
• DOI: 10.11154/pain.40.22

Introduction: Women often experience cyclical pain outside their menstrual phase, suggesting that hormonal fluctuations influence pain perception. Additionally, the pain modulation system, assessed using pressure pain thresholds (PPT) and conditioned pain modulation (CPM), may contribute to cyclical pain. This study investigated the characteristics of cyclical pain in young women during hormonal fluctuations, excluding menstrual pain, and explored whether pain was more closely associated with menstrual–related symptoms (e.g., autonomic dysregulation, water retention, emotional distress) or dysfunction in pain modulation.Methods: This cross–sectional study included 40 healthy women with regular menstrual cycles (mean age: 21.3 ± 4.8; range: 18–30). Participants completed three sessions during the early follicular (EF [E/P–]), the late follicular (LF [E+]), and the mid–luteal (ML [E/P+]) phases, when estrogen and progesterone levels significantly fluctuated. Pain– and menstruation–related symptoms were assessed using the menstrual distress questionnaire (MDQ). Pain modulation was evaluated using the PPT and CPM measurements.Results: The MDQ total pain scores were significantly higher during the E/P+ phase compared to the E/P– and the E+ phases. The subcategory analysis revealed significant positive correlations between pain symptoms and autonomic reactions, water retention, impaired concentration, and negative affect during the E/P+ phase. No significant correlations were found between pain symptoms and the PPT or CPM across all phases.Discussion: Cyclical pain intensified during the E/P+ phase, when estrogen and progesterone levels fluctuated. The relationship between pain symptoms and menstruation–related factors suggests that hormonal fluctuations, rather than dysfunction in pain modulation, predominantly drive cyclical pain.