Girls as young as 12 can receive the contraceptive pill from chemists without their parents' knowledge, new figures show.
The Family Education Trust obtained data under the Freedom of Information Act showing 128 primary care trusts (PCTs) in England allow the morning after pill to be given in pharmacies to girls under the age of 16.
Of these trusts, 70% said they are prepared, under some circumstances, to insist on the drug being available to under-age girls as a condition of granting a pharmacy licence.
The lower age limit requirement ranged from 15 to 12 years old, with some PCTs having no limit at all.
Norman Wells, director of the Family Education Trust, said: "The confidential provision of the morning after pill to teenage girls is a key strand in the government's teenage pregnancy strategy and extravagant claims have been made about its ability to reduce unwanted pregnancy and abortion rates.
"However, the fact that not a single PCT was able to point to any research evidence linking easy access to the emergency pill with a reduction in teenage pregnancy rates suggests that their policies are being pursued out of sheer desperation or blind ideology."
But Juliet Hillier, of Brook, the sexual health charity for young people, said: "Pharmacy provision is essential to improving access to emergency contraception and must continue to be available to all who need it."