Please read Dr. Sabu’s article in PLOS ONE titled, “Small for gestational age and age at menarche in a contemporary population-based U.S. sample.“
Menarche is a significant developmental milestone experienced by girls, and its timing influences biological, social, and psychological development. Over the last century, many developed countries saw a rapid decrease in the average age of menarche. In some countries, the decline has recently stabilized. For example, the National Center for Health Statistics reports that the average age at menarche in the United States has been about 12.5 years since 1995. However, the prevalence of early menarche continues to increase in other countries; e.g., a 2020 study found that the prevalence of early menarche (defined as occurring before 10.5 years of age in this study) increased from 1.8% in 2006 to 3.2% in 2015 in Korea.
Early menarche is usually defined using standard deviation, percentile, or age cutoffs, and has been variably defined as menarche at a time before the age of 10 through 12 years. Early menarche should be distinguished from premature menarche, which is defined as the onset of vaginal bleeding in girls less than 7 years of age and suggests a pathologic process. Early menarche is a concerning phenomenon due to its significant ramifications for the timing of menopause and its relation to obesity. To read the full article.
Small for gestational age and age at menarche in a contemporary population-based U.S. sample. Sabu S, Corman H, Noonan K, Reichman NE, Kuhn KB, Radovick S. PLoS One. 2024 Sep 6;19(9):e0309363. PMID: 39240976 PMCID: PMC11379201 DOI: 1371/journal.pone.0309363