Pharmacokinetics of ethynyloestradiol in women for different populations.

The pharmacokinetics of a dose of 50 microgram ethynyloestradiol administered orally was studied in fourteen centres. Absorption was rapid and the highest serum concentrations of total ethynyloestradiol were found in most subjects at 1 h and by 24 h concentrations were less than 250 pg/ml. Calculation of the half-lives for absorption, distribution and elimination showed wide variations between subjects, the half-life of elimination varying from 2.

A comparative study of the effect of the Progestasert TM and Gravigard IUDs on dysmenorrhoea.

Data obtained from questionnaires on the occurrence of dysmenorrhoea in women using IUDs inserted randomly (146 of them Progestasert and 149 Copper 7) are analyzed. In both groups a reduction in the intensity of menstrual cramps was observed over 12 months of use. Although these reductions are significant in each group, they are slightly higher in Progestasert users.

Rate of metabolism of norethisterone in women from different populations.

The rate of metabolism of orally administered norethisterone was compared in fourteen centres by measuring plasma levels of the steroid by radioimmunoassay at varying times after oral administration of a 1 mg dose. The inter-centre differences were of the same order as the intra-centre differences. Variations in metabolism appeared not to be due to variations in body size.