Abstract. Different aspects of the menstrual pattern including dysmenorrhea, premenstrual tension and working performance during menstruation was studied in three different investigations.

The first study includes 5458 adolescent girls aged 10 to 20. The incidence of invariably painful menstruation was 7.2 per cent during the first gynecological year and 26 per cent five years later. A correlation was found between mothers and daughters for dysmenorrhea as well as for premenstrual tension.

In a second study including 331 girls aged 13 to 20 years the overall absence from school due to pain was 23.4 per cent. The frequency of dysmenorrhea increased from 36 per cent to 56.5 per cent between 13-14 years and 17-20 years.

Socio-medical aspects of menstrual pattern were studied in 865 adult women. Approximately 88 per cent had premenstrual tension and almost 45 per cent had menstrual pain. Thus the treatment of menstrual distress during adolescence is of great importance and the use of modern prostaglandin synthetase inhibitors may be very useful.