International Federation of Gynecology and Obstetrics

Female sex hormone oestrogen has the ability to protect women's health, helping reduce their risk of developing cardiovascular disease, new UK research shows.

Experts found the hormone helps keep the body's immune system in check.

Oestrogen manages to stop white blood cells from sticking to the inside walls of blood vessels, said the researchers, from Queen Mary, University of London.

When this process occurs, dangerous blockages can occur. The scientists said the results show why women tend to have lower rates of cardiovascular disease than their male counterparts.

During the study, the white blood cells from men and pre-menopausal women blood donors were compared.

In pre-menopausal women, there were found to be higher levels of the protein annexin-A1, which prevents the white blood cells from sticking to the walls of blood vessels.

Oestrogen is capable of moving annexin-A1 from the inside of the white blood cell to the surface, stopping sticking from occurring.

"Our results suggest that oestrogen helps maintain the delicate balance between fighting infections, and protecting arteries from damage that can lead to cardiovascular disease," said Dr Suchita Nadkarni from the William Harvey Research Institute at the university.

According to the British Heart Foundation, more than 180,000 people died from cardiovascular disease in the UK in 2009, making it the country's biggest killer.

Posted by Martine Ward