Table 3.

Placebo-controlled RCTs evaluating the effect of progestogens on vasomotor symptoms

Trial	Comparison	Outcome	Difference
Loprinzi	Oral medroxyprogesterone acetate 200 mg twice daily v placebo (crossover) for 9 weeks; 97 women	50% reduction in daily hot flush frequency at 4 weeks (pre-crossover)	34/48 (71%) with medroxyprogesterone acetate v 12/49 (24%) with placebo; RR 2.9, 95% CI 1.71 to 4.89; NNT 3, 95% CI 2 to 4
Aslaksen	Oral medroxyprogesterone acetate 100 mg twice daily v placebo (crossover) for 24 weeks; 21 women	Free from hot flushes at end of study	18/21 (86%) with medroxyprogesterone acetate v 7/21 (33%) with placebo; RR for no flushes 2.60, 95% CI 1.37 to 4.83; NNT 2, 95% CI 2 to 3
		Free from sweating	18/21 (86%) with medroxyprogesterone acetate v 3/21 (14%) with placebo; RR for no sweating 6.0, 95% CI 2.1 to 17.4; NNT 2, 95% CI 1 to 2
Schiff	Oral medroxyprogesterone acetate 20 mg daily v placebo (crossover) for 24 weeks; 27 women	Percentage reduction in hot flushes at 12 week crossover to alternative treatment	74% with medroxyprogesterone acetate v 26% with placebo; P less than 0.05
Leonetti	Transdermal progesterone cream 20 mg v placebo for 1 year; 102 women	Improvement or resolution of vasomotor symptoms as determined by review of weekly symptom diaries (43 women were assigned to treatment group and 47 were assigned to placebo. Thirty women in the treatment group and 26 in the placebo group initially complained of vasomotor symptoms)	25/30 (83%) with transdermal progesterone v 5/26 (19%) with placebo; RR 1.5, 95% CI 1.1 to 2.0; NNT 4, 95% CI 2 to 9
Wren	Transdermal progesterone cream 32 mg daily v placebo for 12 weeks; 80 women	Greene Climacteric Scale and the Menopause Quality of Life Questionnaire	Median change in Greene Climacteric Scale (vasomotor symptoms) from baseline: –1.0 with progesterone v 0 with placebo; P = 0.07