Author(s): MITSUHASHI, R., MACHIDA, S., Institution: JUNTENDO UNIVERSITY, Country: JAPAN, Abstract-ID: 1186

INTRODUCTION:
Menstrual-related symptoms are commonly attributed to female hormones. However, it remains unclear whether symptom severity is more strongly associated with absolute hormone levels or dynamic fluctuation patterns across the menstrual cycle. This study examined the association between oestradiol (E2) and progesterone (P4) secretion dynamics and the severity of menstrual-related symptoms.
METHODS:
Thirty-four women with regular menstrual cycles (age: 23.75±5.16 years, age at menarche: 12.97±2.28 years) were monitored for 1–3 consecutive cycles. Urinary E2 and P4 concentrations were measured every morning using a self-administered female hormone-testing kit. Hormone secretion dynamics were quantified as the peak concentration, rise angle from the first day of menstruation to the peak, fall angle from the peak to the day before the next menstruation, and maximum change angle, representing the largest absolute hormone fluctuations over 1-, 3-, 5-, and 7-day intervals. Menstrual-related symptoms before and during menstruation, including physical, mental, and behavioural changes, were retrospectively assessed using a four-point ordinal scale (0–3). Associations were analysed using generalised linear mixed models with participants as random effects adjusted for age and cycle length.
RESULTS:
For E2, neither the rise nor the fall angle was significantly associated with symptom severity. In contrast, larger maximum change angles of E2 were associated with a lower severity of physical symptoms before menstruation (1-day: p=0.007; 3-day: p=0.005; 5-day: p=0.002; 7-day: p=0.009) and during menstruation (1-day: p=0.006; 3 days: p=0.013; 5 days: p<0.001; 7 days: p=0.002). Larger maximum change angles of E2 were also associated with a lower severity of behavioural changes before menstruation (3-day: p=0.039; 5-day: p=0.010; 7-day: p=0.022) and during menstruation (1-day: p=0.002; 3-day: p<0.001; 7-day: p<0.001). In addition, the maximum change angle of E2 over a 7-day interval was negatively associated with premenstrual mental symptoms (p=0.047).
For P4, steeper rise angles were positively associated with premenstrual mental symptoms (p<0.001), menstrual mental symptoms (p=0.011), and premenstrual behavioural changes (p=0.035). Steeper fall angles were positively associated with premenstrual physical symptoms (p=0.027), menstrual physical symptoms (p=0.027), premenstrual mental symptoms (p=0.031), and changes in premenstrual behaviour (p=0.042). In addition, larger maximum change angles in P4 were positively associated with mental symptoms before menstruation (1-day: p=0.013; 3-day: p=0.020; 5-day: p=0.018; 7-day: p=0.013)
CONCLUSION:
It is possible that the severity of menstrual-related symptoms is more strongly associated with hormone-specific fluctuation dynamics than with absolute hormone concentrations. These findings may suggest that the dynamic changes in E2 and P4 levels during the menstrual cycle are differentially associated with symptom manifestation.