[The menstrual cycle in adolescents].

Data concerning onset and development of menstrual function were received by questionnaire from 740 girls attending the 10th classes of all schools in the city and the county of Jena. Menarche occurred at a mean age of 13 years and 3 months. with a standard deviation of 9.6 months. 6 girls (0,8%) had not yet observed their first bleeding at the time of the investigation. In the group of pupils studied the cycle function became regular at a mean age of 13.7 years including a standard range of 1.2 years. 396 girls observed regular bleeding intervals from the beginning of their menstrual function. 185 after a one year period of irregularity. The normal length of the menstrual bleeding ranging from 3 to 7 days was observed by 89.4% of the girls within the last 12 months prior to the investigation, a regular strength of the bleeding was reported by 82.4% of the adolescents. 39.4% of the girls affirmed the occurrence of primary dysmenorrhoea. For this reason 10 pupils regularly missed the school lessons, while 124 adolescents felt unable to take part on their lessons occasionally. Among the indications leading to gynecological examination or treatment hormonal contraception in 17 cases and artificial abortion in 4 cases are particularly worth mentioning.