Verification of delayed menarche evaluation system based on morphological differences in Korean females

Abstract

In the present study, delayed menarche in Korean females was individually verified by the interval between age at menarche and the age at the maximum peak velocity (MPV) of height derived by the wavelet interpolation method (WIM). However, an evaluation system for delayed menarche has not been established for Korean females. For this reason, the evaluation system for delayed menarche is derived from regression analysis between age at menarche and age at MPV of height. Health examination records of 400 Korean females in their second year at a high school were reviewed from the first grade of elementary school until the second year of high school (from 1997 to 2008). The longitudinal data of height were obtained from the health examination records. The ages at menarche were researched by questionnaires and interview. Finally, 391 subjects for which data were complete were used for the analysis. Least-squares approximation polynomials of age at menarche for age at MPV of height from the first to the third order were constructed for the evaluation in delayed menarche, and the regression equation of the second order was valid. So the quadratic regression evaluation of age at menarche for age at MPV of height was applied for each subject. The morphological factors of fat-thin body and tall-short height types did not affect evaluative judgements of delayed menarche. However, although no significant difference was seen in the short height type, a small significant difference (p<0.1) was seen with the χ2 test in the distribution of the average height type. In any event, constructing a system to evaluate delayed menarche in Korean girls and judging delayed menarche from morphological differences has considerable significance.