Rett syndrome is an almost entirely female based disorder which affects girls.

It affects boys and girls with similar frequency.

It is one of the few mental health problems to affect boys and girls in equal rates.

It affected school-age girls and young women working in factories.

Biliary atresia seems to affect girls slightly more often than boys.

More boys than girls play with action figures, but the lack of a blockbuster movie also affects girls, although in different ways.

In Western nations menstruation begins to affect girls at 13 and menopause starts around 51.

I refer to a disease which affects an estimated 14 million women and girls across the EU.

The disease typically affects boys, but it can also affect girls.