Post-Menarcheal Growth Patterns in a Contemporary Cohort of Latino Girls

Introduction: Menarche is the last stage of pubertal development, which coincides with the completion of longitudinal growth. As a consequence of the lack of national and up-to-date data related to post-menarcheal (PM) growth, the aim of our work was to evaluate PM growth in a group of contemporary healthy Chilean girls followed, prospectively, until 4 years PM. Methods: This study was nested within the GOCS cohort, in a prospective fashion. The girls were followed yearly after menarche for at least for 4 years. We modeled each girl's growth using a SuperImposition by Translation and Rotation (SITAR) model. Results: A total of 534 girls were evaluated prospectively; 399 girls had height measured 2 years after menarche, 421 after 3 years, and 364 of 534 had height measured at 4 years PM. Expected height gained PM in the complete study group was 6.6 +/- 2.5 cm. We observed that the largest gain in height occurred after the first year PM (3.8 +/- 1.5 cm). According to the age of menarche, the group with earlier menarche (<11 years old) had a greater height gain in cm after 4 years PM (8.2 +/- 3.2 cm) and the smallest gain was among girls with menarche at an age older than 13 years (4.4 +/- 1.6) (p < 0.001). Age at menarche was significantly associated with all PM growth patterns (size, timing, and intensity), indicating that girls with older age at menarche grew taller, later, and slower than girls with younger age at menarche. Adjusting the PM growth pattern by BMI maintained all these associations. Applying the SITAR model specifically, girls experiencing menarche after the age of 13 years exhibited slower growth, occurring slightly earlier and with less intensity when adjusted by BMI at menarche. Conclusion: In a national and updated dataset, we observed that girls grew until 4 years PM an average of 6.6 +/- 2.5 cm, with greatest gain occurring in the first year PM (3.8 +/- 1.5 cm). Age at menarche was associated with menarche growth patterns.