Postmenopausal women without previous or current vasomotor symptoms do notflush after abruptly abandoning estrogen replacement therapy

Background: Most but not all women suffer from vasomotor symptoms around me nopause. The exact mechanisms behind these symptoms are unknown, but the ra te of decline in estrogen concentrations has been suggested to affect the r isk of hot flushes. Objective: The objective was to assess whether vasomoto r symptoms were induced in women without previous such symptoms, when the w omen were given combined estradiol and progestagen therapy for 3 months, wh ereafter therapy was abruptly withdrawn. Materials and, Methods: After rand omization, 40 postmenopausal women without previous or current vasomotor sy mptoms were treated transdermally with either 50 mu g/day 17 beta-estradiol or placebo during 14 weeks. During the 13th and 14th weeks, treatment was combined with oral medroxyprogesterone acetate 10 mg/day. Serum estradiol a nd follicle-stimulating hormone (FSH) concentrations were analysed before a nd after 12 weeks of therapy. Climacteric symptoms were assessed at the sam e intervals as well as 8 weeks after the end of therapy. Results: All women had low pretreatment levels of estradiol and high FSH concentrations. Duri ng estradiol therapy estradiol levels increased significantly, whereas FSH only decreased slightly. No woman developed vasomotor symptoms after withdr awal of therapy. Conclusion: Postmenopausal women without previous or curre nt vasomotor symptoms did not develop such symptoms when estrogen replaceme nt therapy was first instituted and then abruptly stopped. Probably other f actors than the rate with which estrogen concentrations decrease determine whether or not a woman will develop vasomotor symptoms. Evidently, estrogen s can be prescribed to a woman who has no vasomotor symptoms, without much risk of inducing such symptoms if she decides to abandon therapy, even afte r 3 months of treatment, (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.