British women were being urged to order the morning-after pill as a precautionary measure as the Christmas party season approaches.

The British Pregnancy Advisory Service (BPAS) is offering to send a pack of the emergency contraceptive Levonelle to women's homes free of charge in a bid to reduce the number of unplanned pregnancies in January.

The morning-after pill is effective for up to 72 hours after unprotected sex occurs but is more likely to work the sooner it is taken.

Gaining access to emergency contraception over the festive season is particularly difficult, as many doctors' offices and pharmacies are closed. The charity warned that this inconvenience, along with the $39 charge if bought directly from a pharmacy, could discourage women from obtaining the pill.

Women who want to take up the offer just need to fill in an online form, and a nurse will call them to check their medical history and ensure they understand how the contraceptive works.

Tracey Forsyth, the BPAS' lead contraception nurse, said of the campaign, "Sometimes women worry that requesting the pill in advance makes it look like you are planning on taking chances. In fact, the opposite is true, making sure you have a backup to help prevent an unwanted pregnancy is making sure nothing is left to chance."

She added, "Having it [the morning-after pill] at home means you are much more likely to take it as soon as you need it."

But pro-life campaigners disagree with this methodology, suggesting that the BPAS is encouraging promiscuous behavior.

Michaela Aston, a spokeswoman for the charity LIFE, said, "If a woman has the morning-after pill at home 'just in case,' she may be more likely to engage in risky sexual behavior than she would normally, particularly over the festive period with the associated increase in alcohol consumption."

UK health secretary Andrew Lansley said, "Emergency contraception is intended to be exactly that for emergencies, not everyday use. Ideally, it would be better for it to be made available in person ... with the benefit of face-to-face advice. Women should be encouraged to use long-acting reversible contraception rather than emergency contraception."