Objective To compare the effects of two postmenopausal regimens on menopausal symptoms, bleeding episodes, side effects and acceptability.

Design Double-blind, randomised controlled trial.

Setting Twenty-nine sites in Denmark, nine in Norway and six in Sweden.

Participants Four hundred and thirty-seven postmenopausal women with menopausal complaints. None of these women had had a hysterectomy.

Interventions Daily treatment with tibolone 2.5 mg (n = 218) or 17β-oestradiol 2 mg plus norethisterone acetate 1 mg (E2/NETA) (n = 219).

Main outcome measures Hot flushes, sweating episodes, vaginal dryness, assessment of sexual life and bleeding patterns; at baseline and after 4,12,24 and 48 weeks.

Results Treatment with either preparation significantly reduced mean scores for hot flushes, sweating episodes and vaginal dryness. The overall discontinuation rate was 28% (tibolone 25%, E2/NETA 31%; P = 0.14), mostly during the first six months. There was a markedly lower cumulative incidence of bleeding or spotting episodes with tibolone compared with E2/NETA (P < 0.0001), mainly during the first six treatment cycles.

Conclusions Both tibolone and E2/NETA effectively alleviate menopausal symptoms. However, tibolone caused significantly fewer bleeding or spotting episodes, which were reflected by lower overall rates of bleeding, as well as lower drop-out rates due to bleeding.