The secular trend in age at menarche in the Netherlands.
The mean age at menarche of girls in Utrecht city, the Netherlands, in 1971 and 1972 was estimated by probit analysis as 13-37 years with a standard deviation of 1-17 years. This result is compared with similar data obtained in the Netherlands in 1955 and 1965.
D000367:Age Factors; D005260:Female; D006801:Humans; D008572:Menarche; D009426:Netherlands