Ministers are to step up efforts to reduce teenage pregnancy rates after a report found the government was set to miss a target to halve them by 2010.
Teenage pregnancy rates in the UK are the highest in Western Europe
The Department of Health said teenage pregnancy rates had been cut by just 11.4% since 1998 in England.
But ministers have said rates are at their lowest for 20 years and efforts are being "redoubled" to hit targets.
The Family Education Trust charity told the Sunday Telegraph the report showed the government's strategy was failing.
While rates of pregnancy among under-18s are at their lowest for two decades, the total number is up because of a rising teenage population.
Figures are the highest in Western Europe - twice as high as in Germany, three times as high as in France and six times as high as in the Netherlands.
Norman Wells, of the Family Education Trust, told the Sunday Telegraph that the government had allowed the "systematic removal of every restraint that used to act as a disincentive to under-age sex".
"The problems associated with teenage pregnancy will never be solved so long as the government persists with its reliance on yet more contraception and sex education," he said.
Viv Crouch, a former advisor to the government on the issue, said better sex education in schools was needed.
"We are frightened of teaching it," she said.
"I think that until the government decides that personal and social and health education, where sexual relationships education fits in [is made] a mandatory subject, I think we won't progress any further."
The Department for Children, Schools and Families - jointly responsible for the target with the Department of Health - said efforts would be "redoubled" in a bid to meet the "stretching" target.
"We made a commitment to reduce the teenage conception rates and to improve the quality of life for all young people, and we are already delivering on that," it said in a statement.
"However, we make no apology for setting stretching targets and will be redoubling our efforts to continue to reduce the rate of teenage pregnancy by 2010."
It added that its strategy was being supported by two national media campaigns which advise young people to resist peer pressure to have sex and to use condoms if they are already sexually active.