Dennerstein L, Burrows G D, Hyman G, Wood C
Br J Obstet Gynaecol. 1978 Nov;85(11):852-6. doi: 10.1111/j.1471-0528.1978.tb15842.x.
A double blind crossover study was planned in order to compare the effects of oestrogen, progestogen and placebo on hot flushes. The 49 women studied had previously undergone hysterectomy and bilateral oophorectomy. The drug regimen consisted of three months each of ethinyl oestradiol 50 microgram/day, d norgestrel 250 microgram/day, a combination of these two substance ("Nordiol") and a placebo. The predominant reason for requesting a change of medication was intolerable hot flushes associated with placebo use. All hormonal preparations were found to be significantly more effective than placebo in reducing hot flush frequency and intensity. Oestrogen containing medications were more effective than the progestogen (norgestrel).