A review of the research evidence suggests that hormone replacement therapy increases the risk of a stroke.

Some studies have suggested that hormone replacement therapy (HRT) can increase the risk of stroke, while others have pointed to a protective effect. In a review of 28 trials, researchers at the University of Nottingham find that HRT is associated with a 29 per cent increase in stroke risk. This is especially true for ischemic stroke, caused by a blood clot in the brain. And the severity of the stroke was increased by HRT. Further work is needed, however, to work out why HRT should make women more vulnerable to stroke - especially as some research has suggested the opposite. In the meantime, HRT certainly cannot be recommended for stroke prevention, the researchers say.