Pubertal development and risk of premenstrual disorders in young adulthood.

study questionIs 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,

methodsWe 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

findingsOur 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.