A halt in the secular trend towards earlier menarche in Denmark

Background. A halt in the decrease of menarcheal age has been reported in some countries but has not been documented in Denmark. Methods. The entire population of schoolgirls, attending grades 5 through 10 (n=979), in a particular region of Denmark was investigated by the status quo method in 1996. Similar investigations had been made in the same region and by the same method in 1966 and 1983. Mean age and standard deviation were estimated by probit analysis. Result. Mean age was 13.00 years (s.e. =0.080; s.d. = 1.15) and almost identical with the mean age in 1983 (13.03 years), but significantly different from the mean age in 1966 (13.40 years). Conclusion. The results indicate a halt in the secular trend towards earlier menarche in the region at some time between 1966 and 1983.