Natural History of Menstrual Pain and Associated Risk Factors in Early Adolescence.

Study objective: To determine the natural history of menstrual pain without pelvic pathology, the role of progesterone in its pathophysiology, and associated risk factors in a longitudinal study of early postmenarchal girls in North Carolina.

Methods: Participants contributed daily urine samples for up to 3.5 years to measure pregnanediol-3-glucuronide (PdG) (mean 589 urines/participant), completed menstrual diaries, and reported menstrual pain using the Menstrual Symptom Questionnaire (MSQ) biannually. MSQ scores were log-transformed and generalized estimating equations assessed associations with gynecologic age, cycle peak PdG, presumed ovulation, physical activity, anxiety, and depression. Models were adjusted for age at menarche, baseline body mass index, race/ethnicity, parental education and employment, and gynecologic age.

Results: Forty-three girls, aged 12.6 ± 1.1 years (mean ± SD) at enrollment with a gynecologic age 0.3 ± 0.2 years, participated. Total MSQ scores were higher for every 1-year increase in gynecologic age (MSQ score ratio: 1.12; 95% CI: 1.08, 1.17; P < .0001). Overall MSQ (ratio: 1.04; 95% CI: 1.02, 1.06; P = .0002) and abdominal pain-specific (ratio: 1.04; 95% CI: 1.01, 10.7; P = .004) scores were higher for every 1000 ng/mg creatinine increase in peak PdG in the preceding cycle. Overall MSQ scores were higher (ratio 1.26; 95% CI: 1.11, 1.44; P = .0005) if the preceding cycle was presumed ovulatory. Menstrual pain was not associated with physical activity, anxiety, or depression.

Conclusions: In early postmenarchal girls, gynecologic age and PdG were associated with menstrual pain, suggesting a pathophysiologic role for progesterone and other unknown factors in the development of menstrual pain.