Relationship between age at menarche and adult body mass index (BMI)

The aim of the present study was to investigate the relationship of age at menarche with adult the BMI during 2001-2005 among 863 females in the age from 18 to 65 and 66+ years in Latvia.The data from this study included some anthropometrical measurements (body height. (cm) and body weight (kg)). The age at menarche was obtained by a questionnaire. The body mass index (BMI) was calculated, and it was categorized as underweight, normal, overweight and obesity. All the women were divided into four categories by age at menarche (I (early) - before 11.99 years; II - 12.0-12.99 years, III - 13.0-13.99 years; IV (late) - older than 14 years) and into seven age groups (18-20, 21-25, 26-35, 36-45, 46-55,56-65,66+).The mean age at menarche was 13.39 +/- 1.35 years. 40.7% of all the measured women matured at the age older than 14 years and 31.6% - at the age 13.0-13.99 years. Menarcheal age was inversely related to the adult levels of the BMI among adults in some age groups. Menarcheal age was not significantly related to adult height, but early maturers were shorter than late maturers. The mean BMI was 23.29 +/- 4.58 kg/m(2). About 66.5% of women had normal body weight and 17.8% of women were overweight. The women with ages at menarche before 11.99 years and during 12.0-12.99 years showed higher mean BMI values compared with the BMI values of women matured after the age 13.0-13.99 years and older than the age 14. The mean ages of menarche of women with underweight and obesity showed a tendency that these women matured later than the women with a normal body weight and overweight.