PubMed1984
In Belgium, as in most industrialized countries, studies about menarcheal age have shown an earlier physical and sexual maturation. In this paper we will consider the secular trend in menarcheal age over the last twenty years in Brussels. The results concerning menstruation have been obtained in 1980-1982 from 1048 Belgian girls aged between 9 and 17. These girls have very varied socio-economic backgrounds, representative of the diversity of social origin in the Belgian population of Brussels (city and suburbs). Our data were collected using the status quo-method and compared with Jeurissen's (menarcheal age in Belgium between 1915 and 1959). Percentiles and probits were used. The lower limit, where 10% of the girls have had their menarches remains more or less constant. Between 1915 and 1959, Jeurissen noted the tendency of the median menarcheal age toward earlier sexual maturation from 14 years 4 months to 13.0. But, for the first time in Belgium, it seems that the median age is stabilized at 13.0 years. However, the higher limit (age, where 90% have had their menarches) is attained at a lower age: 15.0 for girls born between 1950-1954 and 14.0 in our sample. In conclusion, it seems that better conditions of life cause an evolution in the cases of late menarches but have no more repercussions on the median menarcheal age in this Belgian group.