Young girls will be "particularly susceptible" to the controversial first TV advert for the morning-after pill, a campaign group warned today.
The broadcast will be shown after the 9pm watershed across a range of channels, including ITV, Channel 4 and Sky.
Viewers will see a woman waking up next to her partner and later asking for Levonelle One Step at a pharmacy.
While the advert was welcomed by some, Dominica Roberts, of the ProLife Alliance, said: "It is advertised inaccurately as emergency contraception, when in fact its major function is to cause the abortion of an embryo that has already been conceived, not as suggested by the name to prevent conception.
"Young girls will be particularly susceptible to this advertising campaign, and it is foolish to imagine they do not watch TV after the 9pm watershed."
The morning-after pill is available to women aged 16 and over through the NHS or to buy at most pharmacies.
Sexual health charity Marie Stopes International welcomed the first screening of the advert.
Spokeswoman Emily James said: "Marie Stopes International is delighted that emergency contraception, a vital component in the prevention of unintended pregnancies, will be advertised on TV.
"A condom breakage can be a nightmare for many women. Such adverts will inform and educate women about what to do in this situation.
"The sooner a woman takes emergency contraception after having unprotected sex, the more effective it is.
"Catapulting information on how to access and use emergency contraception into women's living rooms is an ideal way to ensure women will use it quickly and effectively."
Levonelle One Step is the only morning-after pill available to women in the UK.
Julie Bentley, chief executive of the FPA (formerly the Family Planning Association), said: "Ensuring women know where emergency contraception is available to them is important.
"It is also really important that they know it is most effective in the first 24 hours after having unprotected sex, and that it is available free from contraceptive clinics and GPs as well as at a cost from pharmacies."
A spokeswoman for manufacturer Bayer Schering Pharma said television advertising was an effective way of providing information about the morning-after pill.
She said: "If regular contraception fails, women need to know that emergency contraceptive options are available and where advice can be sought.
"However, our research has shown not all women are aware of the facts about the emergency contraceptive pill and that some women cross their fingers and hope for the best instead of taking action when their regular contraception lets them down.
"We believe TV advertising plays an important role in informing women about Levonelle One Step and how and where it can be obtained."