By Pooja Toshniwal PahariaJun 5 2024Reviewed by Danielle Ellis, B.Sc. In a recent study published in JAMA Network Open, researchers examined the temporal trends and inequalities in menstruation onset, time to regularity, and the role of early-life body mass index as a mediator.
About the study In the present study, researchers assessed temporal changes in menstruation onset and time taken for regular menstrual cycles in a racially and ethnically diverse sample group born between 1950 and 2005. They examined general temporal patterns and whether they differed by sociodemographic characteristics. They also investigated whether BMI at menarche would explain the observed temporal patterns.
The BMI z-scores were derived using the Centers for Disease Control and Prevention's growth charts. They also performed an exploratory causal mediation analysis to determine the proportions of temporal trends in menarche regularity mediated by BMI z-scores at menarche. They used extended linear regressions and multinomial logistic regressions to conduct their investigation. Covariates in the study were race, ethnicity, subjective socioeconomic position , and geographic location.
Among 61,932 individuals with time to regular menstrual cycles, the number attaining regularity within two years fell from 3,463 to 4,075 , while the number with not yet attained menstrual regularity rose from 153 to 1,375 .