The study in the British Medical Journal showed that those who used estrogen patches to control symptoms of menopause did not have any higher risk of stroke than women who did not use hormone replacement therapy (HRT).
This study adds to a very slow growing body of evidence that could rehabilitate the use of HRT.
The use of HRT plummeted in 2002 after a large study found an increased risk of ovarian cancer, breast cancer, strokes and other health problems.
Authors of the study say delivering low doses of hormones through the skin bypasses the liver and may reduce the whole body effects.
