Girls are starting sex at ever younger ages – but boys, it seems, are not.

The trend, revealed in the annual Health Survey for England 2010, published yesterday, triggered claims about the "pornification" of British culture.

The survey found more than one in four women (27 per cent) aged 16 to 24 said they'd had sex before the age of 16 – the legal age for consent – compared with just over one in five men (22 per cent).

The proportion of women who say they had under-age sex has increased over the generations but the trend is "less clear" in men, the report says. One in 10 men and women aged 16 to 24 said they had had 10 or more sexual partners.

Diane Abbott, Labour's shadow Health Minister, said: "The underlying cause must be the 'pornification' of British culture and the increasing sexualisation of pre-adolescent girls.

"Too many young girls are absorbing from popular culture that they only have value as sex objects."

The authors warned that surveys of sexual behaviour are hard to interpret as responses are subject to exaggeration and concealment.