Britain's House of Lords may ban over-the-counter sales of the "morning after" birth control pill, only weeks after being the first country to make it available without a prescription.

"(It says) to girls and boys that unprotected sex is alright," says Conservative member Baroness Young, who put forward the motion Monday.

The House of Lords is the upper house of Parliament.

Regular birth control pills

The new law had just come into place Jan. 1. It is aimed at reducing the country's high rate of unwanted births and abortions.

The law allows women aged 16 and over to have access to the pill – which can be used up to 72 hours after sex. The decision to allow over the counter sales came after seven years of studies and discussions.

But Young says it is impossible to enforce the rule.

"It will be impossible for the chemist to know whether the girl before him is over or under 16," says Young.

Morning after pills don't terminate pregnancies

The pills are low-dose birth control pills which prevent either ovulation, fertilization or implantation of a fertilized egg in the uterus. This is not an "abortion" pill, it is unable to terminate a pregnancy if it has already begun.

The pills are available for $29 after the woman completes a questionaire.

Doctors say the law would have helped reduce abortion rates and family planning organizations applauded the move.

Young says there's no evidence to suggest that the rate of teenage pregnancy in Britain would be reduced through this method.

Instead, Young says the government should look at programs around the world, such as the U.S., where the rate of teenage pregnancies have decreased.

In Canada, B.C. is the only province to allow pharmacists to distribute the pills without prescription.

Health Canada has approved prescription of the pills in 1999.

Abortion pill under study in Canada

The pills should not be confused with RU-486, better known as the abortion pill.

In the U.S., RU-486 was given approval last September. It is sold under the brand name Mifeprex.

Approval of the pill comes with several conditions, such as mandatory visits to doctors two weeks after taking the pill to determine if the pregnancy was terminated.

Health Canada started clinical trials last fall of the pill using about 1,000 women across the country.

RU 486 can be taken early in a woman's pregnancy, up to five weeks after conception.

The pill induces uterine contractions, bleeding and miscarriage. It is effective 95 per cent of the time.