Subgroup analysesSubgroup analyses by dose of BHT suggested that higher doses of BHT may be associated with more effectiveness but also higher risk of adverse effects .
There was low to moderate quality evidence that BHT in various forms and doses is more effective than placebo for treating moderate to severe menopausal hot flushes .
There was some evidence to suggest that higher doses of BHT are associated with greater effectiveness but also with higher risk of adverse effects .
No data are yet available about the safety of BHT with regard to long-term outcomes such as heart attack , stroke and breast cancer .
BACKGROUND Various hormone therapies ( HT ) are available to treat  menopausal vasomotor symptoms .
Bioidentical hormones are chemically identical to those produced by the human body , and several types are well-tested and available on prescription .
Many women have opted for bioidentical hormone therapy ( BHT ) on the assumption that it is safer than other forms of HT .
We evaluated the evidence .
OBJECTIVES To determine the effectiveness and safety of bioidentical hormones compared to placebo or non-bioidentical hormones for the relief of vasomotor symptoms .
Early effects of continuous low-dosage all-norgestrel administered alone or with estrogen.
Twenty-six postmenopausal women participated in a double-blind trial involving treatment according to a Latin square design with either ( i ) dl-norgestrel alone ( 0.075 mg/day ) continuously for two cycles , ( ii ) estradiol-17 beta alone ( 1 mg on 25 of 28 days ) for two cycles , or ( iii ) the combined hormones for six cycles . A placebo control cycle followed each hormonal treatment . Plasma triglycerides decreased by an average 22 % during treatment with either dl-norgestrel alone ( 123 + /- 11 vs. 160 + /- 10 mg/dl , n = 25 , P < 0.005 ) or combination therapy ( 126 + /- 11 vs. 162 + /- 11 , n = 25 , P < 0.005 ) as compared with control . Plasma total cholesterol fell by 5 % during two cycles of treatment with either dl-norgestrel alone ( 229 + /- 11 vs. 242 + /- 10 mg/dl , n = 25 , P < 0.02 ) or combination therapy ( 233 + /- 11 vs. 246 + /- 10 , n = 25 , P < 0.05 ) versus placebo . During the fifth and sixth cycles of combination therapy 94 % of cycles were free of flushing ( vs. 31 % for control , P < 0.01 ) , 64 % of cycles were free of spotting not requiring protection ( control 75 % ) , 96 % of cycles were free of vaginal bleeding ( control 100 % ) , endometrial biopsy showed inactive endometrium in nine of the 10 subjects re-biopsied , fasting blood pyruvate decreased by 20 % ( P < 0.05 ) and diastolic blood pressure fell by 4 % compared with control ( P < 0.05 ) , whereas glucose tolerance was unchanged . There was a significant reduction in vasomotor flushing beginning with the third to fourth cycles of combination therapy
Subgroup analysesSubgroup analyses by dose of BHT suggested that higher doses of BHT may be associated with more effectiveness but also higher risk of adverse effects .
There was low to moderate quality evidence that BHT in various forms and doses is more effective than placebo for treating moderate to severe menopausal hot flushes .
There was some evidence to suggest that higher doses of BHT are associated with greater effectiveness but also with higher risk of adverse effects .
No data are yet available about the safety of BHT with regard to long-term outcomes such as heart attack , stroke and breast cancer .
BACKGROUND Various hormone therapies ( HT ) are available to treat  menopausal vasomotor symptoms .
Bioidentical hormones are chemically identical to those produced by the human body , and several types are well-tested and available on prescription .
Many women have opted for bioidentical hormone therapy ( BHT ) on the assumption that it is safer than other forms of HT .
We evaluated the evidence .
OBJECTIVES To determine the effectiveness and safety of bioidentical hormones compared to placebo or non-bioidentical hormones for the relief of vasomotor symptoms .