Uterine effects of 3-year raloxifene therapy in postmenopausal women younger than age 60.
OBJECTIVE
To assess the uterine effects of 3 years of therapy with raloxifene in healthy, postmenopausal women under age 60.


METHODS
Integrated data from two identically designed, randomized, double-masked, placebo-controlled clinical trials were analyzed. Nine hundred sixty-nine healthy women with uteri (ages 45 through 60, 2 to 8 years postmenopausal) were assigned randomly to raloxifene 30, 60, or 150 mg per day, or an identical placebo for 3 years. Endometrial thickness was evaluated with transvaginal ultrasonography every 6 months for 2 years and again after 3 years. Further uterine evaluation, including endometrial sampling if necessary, was initiated for vaginal bleeding or findings of endometrial thickness greater than 5 mm.


RESULTS
Endometrial thickness was unchanged by raloxifene and not significantly different from placebo at any time. One hundred seventy-two women had at least one episode of endometrial thickness greater than 5 mm or vaginal bleeding distributed equally among all groups. A total of 102 (10.5%) women underwent endometrial sampling at least once: 15 (1.5%) for vaginal bleeding, 78 (8.0%) for endometrial thickness greater than 5 mm, and nine (0.9%) for other reasons. There were no significant treatment differences in the proportion of women sampled, in the clinical findings, or in the histologic diagnoses.


CONCLUSIONS
Raloxifene given to healthy postmenopausal women at doses from 30 to 150 mg per day does not stimulate uterine growth and does not cause vaginal bleeding, spotting, or discharge through 3 years of therapy. Thus, any bleeding during therapy should be deemed unexpected and prompt a clinical evaluation.
Cohen
F J
FJ
Lilly Research Laboratories, Eli Lilly and Co., Lilly Corporate Center, Indianapolis, Indiana 46285, USA.
Watts
S
S
Shah
A
A
Akers
R
R
Plouffe
L
L
D004717:Endometrium / Q000187:drug effects; D005260:Female; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause; D020849:Raloxifene Hydrochloride / Q000494:pharmacology* / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D020845:Selective Estrogen Receptor Modulators / Q000494:pharmacology* / Q000627:therapeutic use; D014599:Uterus / Q000187:drug effects*
D020845:Selective Estrogen Receptor Modulators; D020849:Raloxifene Hydrochloride