This 64-week prospective cohort trial evaluated the effects of 20-mg oestradiol implants, replaced every 4 months, in healthy postmenopausal women aged 45-65 years. Of 20 implant and 14 control subjects who remained in the trial at 32 weeks, 13 implant and seven controls continued to 64 weeks, with no baseline differences between completing and dropout subjects. At 64 weeks, implant subjects displayed increases of 5.4-7.6% in spine and hip bone mineral density ( p<0.05 versus controls). The abdominal fat-to-lean soft tissue ratio decreased by 18% in implant subjects ( p<0.001), but did not change in controls ( p<0.05 implants versus controls). Neither group displayed significant changes in weight, %fat or appendicular skeletal muscle mass. The 32-week data were consistent with these results. Hence, oestradiol implant therapy can reduce abdominal adiposity and could lower the risk of obesity-related metabolic disorders.