There's a large genetic predisposition, which may be inherited from the father or mother.

Androgenetic alopecia affects roughly 50 per cent of men (seen as typical balding in men). Research has suggested that that over the age of 65 as many as 75 per cent of women are affected.

Women's pattern of hair loss is different to the typical receding hairline and crown loss in men. Instead, androgenetic alopecia causes a general thinning of women's hair, with loss predominantly over the top and sides of the head.