[Menarche in healthy and sick girls with special reference to mongolism]

The age of menarche in various groups of females was studied. In healthy girls, the average age of menarche was 12 years 2 months regardless of their birthweights. Twin girls had a significantly retarded menarche (approx. 12 years 8 months). In a group of 102 blind patients, it was not significantly different from healthy controls. In a series of 42 girls with mongolism, the mean age of menarche was significantly retarded (13 years 3 months).