Is hemophilia happening more or less frequently?

No, it remains SAME: Hemophilia a and b, most common types of hemophilia are hereditary conditions. The gene is usually passed on from a mother who is a carrier of the gene to her son. Although women and girls could suffer from hemohpilia, it is very rare. Hemophilia is thus usually a disese only present in males. A spontaneous mutation of a normal gene to hemophilia gene ocasionally occurs.