Menopausal hormone therapy for vasomotor symptoms: balancing the risks and benefits with ultra-low doses of estrogen.

Estrogen therapy is the most consistently effective treatment and the only therapy approved by the FDA for menopausal vasomotor symptoms. Following the safety issues reported in the primary Women's Health Initiative publications and with continued patient requests for treatment, a challenge to clinicians has been to identify the lowest effective dose of estrogen for alleviating menopausal symptoms. A number of low-dose estrogen preparations are now available, and transdermal preparations containing an ultra-low dose (25% of the previous conventional or standard dose) of estrogen have recently been approved by the FDA. These preparations effectively relieve menopausal symptoms such as vasomotor symptoms and vaginal atrophy, and potentially protect against bone loss. Compared with standard-dose estrogen therapy, these ultra-low-dose products have an improved tolerability profile and may require reduced amounts or a lower frequency of progestogen administration, potentially mitigating the apparent long-term adverse effects of estrogen-progestogen combinations, as noted in the Women's Health Initiative.