['Estriol is an estrogen with considerably weaker stimulatory effects on endometrial proliferation than estradiol. A study was conducted to determine the effects of oral estriol on vaginal flora and endometrial thickness.', 'Fifty-nine postmenopausal women (50-75 years of age), complaining of pruritus or vaginal discharge, participated in the study. Vaginal flora and endometrial thickness were evaluated before treatment and after receiving oral estriol (2 mg/day) for 14 days.', 'Prior to treatment, lactobacilli were found in vaginal cultures from only six of the 59 study participants, whereas after treatment, the vaginal flora of 27 women showed a presence of lactobacilli (P<0.0001). Endometrial thickness exceeded 5 mm in only five cases. No side effects were reported.'] Does short term oral estriol treatment restore normal premenopausal vaginal flora to elderly women?