Aim: The aim of the present work was to assess the influence of estradiol administration mode on the plasma IGF-I, IGFBP-1, IGFBP-3 levels in postmenopausal women treated with norethisterone acetate.
Material and methods: 39 women were enrolled into the study Group A--14 women received transdermal 17beta-estradiol (Oesclim 50--Fournier-Solvay) combined with oral norethisterone 2.5 mg daily (Primolut-Nor--Schering), Group B--10 women on oral 2 mg 17beta-estradiol combined with oral 1 mg daily norethisterone (Kliogest--Novo-Nordisk). Control group (group C) consisted of 15 postmenopausal women who received no treatment. Basic plasma FSH, estradiol and total IGF-I, IGFBP-1 as well as IGFBP-3 levels were measured initially and at the 52nd week of the study.
Results: The mean plasma FSH level was reduced and mean plasma estradiol level was increased in groups A and B during hormone therapy. Mean plasma levels of total IGF-I, IGFBP-1, IGFBP-3 as well as IGFBP-3/IGF-I ratio did not changed significantly during 52 weeks of observation in groups A, B and C. The comparison of plasma IGF-I, IGFBP-1, IGFBP-3 between groups at the initial visit and after 52 weeks showed the lowest concentration f IGBP-3 in group B. Other parameters showed no differences among the three groups.
Conclusion: Mode of administration of estradiol did not influenced the plasma levels of IGF-I, IGFBP-1, IGFBP-3 in postmenopausal women treated with norethisterone acetate.