Lack of effect of isoflavonoids on the vagina and endometrium in postmenopausal women.
OBJECTIVE
To determine the effects of soy-derived isoflavones on vaginal epithelium and the endometrium.


METHODS
Double-blind, randomized, placebo-controlled crossover trial.


METHODS
Outpatient clinic of a university hospital.


METHODS
Sixty-four postmenopausal women with a history of breast cancer.


METHODS
The women took (in a randomized order) 114 mg of isolated isoflavonoids or placebo in tablets daily for 3 months; the treatment regimens were crossed over after a 2-month washout period. The subjects were studied before and on the last day of each treatment period.


METHODS
Vaginal dryness, maturation index (MI) of vaginal epithelium, endometrial thickness, histology, and expression of estrogen (E) and progesterone (P) receptors and the proliferation marker Ki-67 in the endometrium.


RESULTS
Isolated isoflavones did not relieve vaginal dryness. Maturation index values remained unchanged during the isoflavone regimen, but decreased during the placebo regimen. No changes were found in any of the variables measured in the endometrium.


CONCLUSIONS
Daily administration of 114 mg of isolated isoflavones for 3 months had no effect on the subjective perception of vaginal dryness or on objective findings in the vagina or endometrium. This implies safety with regard to the endometrium.
Nikander
Eini
E
Department of Obstetrics and Gynecology, Helsinki University Central Hospital, Helsinki, Finland. eini.nikander@pp.fimnet.fi
Rutanen
Eeva-Marja
EM
Nieminen
Pekka
P
Wahlström
Torsten
T
Ylikorkala
Olavi
O
Tiitinen
Aila
A
D000328:Adult; D000368:Aged; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004717:Endometrium / Q000187:drug effects* / Q000473:pathology; D005260:Female; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology*; D019394:Ki-67 Antigen / Q000032:analysis; D008875:Middle Aged; D017698:Postmenopause; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D014621:Vagina / Q000187:drug effects*
D007529:Isoflavones; D019394:Ki-67 Antigen; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone