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Menstrual pattern and self-reported abnormal uterine bleeding in Brazilian adolescents: A multicenter cross-sectional
Renan Massao Nakamura1, Gabriela Pravatta Rezende2, Daniela Angerame Yela1
1School of Medicine, University of Campinas (UNICAMP), Campinas, Brazil.
Objective:
This study describes the menstrual patterns and prevalence of heavy menstrual bleeding among Brazilian adolescents, compared to adult women, and assesses the impact of heavy menstrual bleeding on their quality of life.
Methodology:
This multicentric cross-sectional study was conducted over 2021 and 2022 and included 1761 women, of whom 195 were adolescents of reproductive age (≤19 years old). Sociodemographic data, menstrual cycle characteristics, and self-perception of the effects on quality of life of menstrual bleeding were collected through questionnaires.
Results:
The mean age of adolescents was 16.70 ± 1.99 years; 18.5% of participants were classified as overweight or obese. The mean age of menarche was 11.88 ± 1.16 years old. Heavy menstrual bleeding was reported by 20.51% of the adolescents, compared to 32.76% of the adults (P < 0.001), and 38.53% had been diagnosed with anemia. A significant percentage of adolescents (61%) reported an impact of menstrual cycles on their quality of life, with 74.9% experiencing dysmenorrhea. Among adolescents with heavy menstrual bleeding, 57.5% reported menstrual cycle irregularity; among adolescents without heavy menstrual bleeding, 16.1% reported menstrual cycle irregularity.
Conclusion:
The prevalence of heavy menstrual bleeding was 20.5% among Brazilian adolescents. Most of them had irregular cycles, with periods of amenorrhea in 38%. A large percentage of them reported worsening in their quality of life during menstrual bleeding, and 38.5% had already experienced anemia throughout their life.
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