The age at menarche in Carabobo, Venezuela with a note on the secular trend

A study of the age at menarche was conducted in the state of Carabobo as part of Project Venezuela, a National Human Growth, Nutrition and Family Survey. The study was performed during 1978 on a cross-sectional random stratified sample which included 955 girls between the ages of 9 and 20 years. Data were collected using the status quo method. The median age at menarche was estimated by logits at 12.68 0.08 for all socio-economic groups. Sexual maturation occurred earlier in girls from stratum III and later in those from strata IV and V; 12.34 0.11, 12.59 0.11, and 12.86 0.12, respectively. Small sample size did not permit comparisons with strata I and II girls. The results indicate a secular trend in the age of menarche when compared with previous Venezuelan studies. Median age for all Carabobo girls is comparable and often slightly lower than recent data from European and American studies.