The morning-after pill has been made officially available in all pharmacies to girls under 16 for the first time.
The drug, called ellaOne, which can be effective up to five days after intercourse, will be on offer nationwide to girls under the age of consent.
Although the emergency contraception is currently given to young women by many pharmacists, this is the first blanket nationwide licensing.
Existing NHS policy allows certain pharmacists to supply teenagers with a morning-after pill such as Levonelle, which works up to three days after unprotected sex.
Although girls under 16 are below the age of consent, the trial scheme means they can take action if they are worried they have become pregnant.