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 .
Efficacy and Local Tolerance of a Low‐Dose, 7‐Day Matrix Estradiol Transdermal System in the Treatment of Menopausal Vasomotor Symptoms
Objective To determine the efficacy and local tolerance of a new matrix transdermal drug-delivery system that delivers 0.02 mg of 17β-estradiol ( E2 ) daily for 7 days for the relief of vasomotor symptoms . Methods A total of 324 surgically or naturally menopausal women , all with prior hysterectomy and moderate to severe vasomotor symptoms ( 56 - 140 hot flushes per week , with episodes of sweating , during a baseline observation period ) , participated in two independent , 12-week , r and omized , double-blind , placebo-controlled studies . After a 4-week , treatment-free period , each woman received a continuous regimen of either one E2 transdermal system , two E2 transdermal systems , or placebo transdermal system(s ) applied every week for 12 weeks . Efficacy was measured as reduction in hot flush frequency , determined from subject diaries . To measure local tolerance , skin irritation ( erythema and edema ) was objective ly and systematic ally evaluated under blue light after removal of the transdermal system(s ) . Serum E2 and estrone concentrations were determined in one of the studies during baseline and on days 1 , 9 , 30 , 58 , 79 , and 84 . Results Mean hot flush frequency decreased from 80 hot flushes per week at baseline to approximately 13 hot flushes per week ( 84 % decrease ) after 12 weeks of transdermal E2 treatment . Compared with placebo , the decrease in hot flush frequency was significant as early as weeks 2 and 3 , and was maintained through the end of the study . Few clinical ly significant skin reactions occurred , and only nine ( 3 % ) of the subjects withdrew because of a skin effect . After initial increase , serum E2 concentrations remained stable throughout the study , achieving values of approximately 20 and 40 pg/mL above baseline for one and two E2 transdermal systems , respectively . Conclusion The E2 transdermal system effectively reduced the frequency of moderate to severe vasomotor symptoms as early as the second week of therpy and was very well tolerated . The decrease in hot flush frequency was similar to that reported for oral and other transdermal estrogens , but at lower serum E2 concentrations . This result may be due to the stable E2 blood level achieved with this transdermal system
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 .