Estrogen-progestogen replacement therapy in postmenopausal women--is 1 mg estradiolvalerate sufficient to maintain...

An oral estrogen-progestogen replacement therapy consisting of 1 mg estradiolvalerate +2 mg estriol/day for 21 days in combination with 0.25 mg levonorgestrel/day for the last 10 days sequentially may be sufficient to maintain lumbar trabecular bone density in climacteric pre- and postmenopausal women as demonstrated by serial bone density measurements (single-energy quantitative computed tomography of the lumbar spine) in 7 individuals with longitudinal follow-up for up to 5 years. At present, only postmenopausal women with induced estradiol levels of at least > or = 220 pmol/l (> or = 60 pg/ml) provided by estrogen replacement therapies containing higher daily estradiol doses as the above described preparation have been shown to be protective against loss of trabecular bone at the lumbar spine. Preliminary pharmacokinetic results obtained from 14 postmenopausal women being treated with the low-dose estrogen-progestogen replacement demonstrated peak estradiol concentration of 120-160 pmol/l (32-43 pg/ml) 10 hours after oral ingestion, suggesting bone preserving properties by these considerably lower estradiol concentrations.