Treatment of Vasomotor Symptoms of Menopause with Black Cohosh, Multibotanicals, Soy, Hormone Therapy, or Placebo

Randomized placebo-controlled trial in women aged 45 to 55 years in the menopausal transition or postmenopause who had two or more vasomotor symptoms per day. Participants were recruited from Group Health in Washington State and were predominantly white and well educated. Active intervention arms included black cohosh, multibotanical, multibotanical plus soy counseling, and hormone therapy, with follow-up through 12 months.

Black cohosh was given as Actaea racemosa or Cimicifuga racemosa 160 mg daily as a 70% ethanol extract standardized to 2.5% triterpene glycosides. The multibotanical arm received a daily ProGyne formula containing black cohosh 200 mg, alfalfa 400 mg, boron 4 mg, chaste tree 200 mg, dong quai 400 mg, false unicorn 200 mg, licorice 200 mg, oats 400 mg, pomegranate 400 mg, and Siberian ginseng 400 mg. A third herbal arm received the same multibotanical formula plus soy diet counseling, and the hormone therapy arm received conjugated equine estrogen 0.625 mg daily with medroxyprogesterone acetate 2.5 mg for women with a uterus or estrogen alone for women without a uterus.

Black cohosh and the multibotanical regimens did not provide clinically meaningful relief of vasomotor symptoms versus placebo, while hormone therapy clearly did. For vasomotor symptoms per day over all follow-up, the adjusted treatment effects were -0.54 for black cohosh, 0.43 for multibotanical, 0.09 for multibotanical plus soy counseling, and -4.06 for hormone therapy; hormone therapy was significant at P < 0.001. Symptom intensity and Wiklund vasomotor scores were likewise not meaningfully improved by the herbal arms, and the multibotanical plus soy counseling arm showed a higher intensity score at 12 months, 0.15 (0.03 to 0.27). Short-term tolerability was generally acceptable, although hormone therapy had more menstrual disorders and breast discomfort, and the herbal arms had mostly mild gastrointestinal upset, headache, and fatigue.

Generalizability is limited because participants were largely white, relatively well educated, and recruited from a single integrated health plan in Washington State. The active supplement comparisons were modest in size, and the soy counseling arm combined an herbal product with dietary counseling, which makes the specific supplement effect harder to isolate. Outcomes were symptom-based and the trial was not designed to establish long-term safety.