Women may be able to protect themselves from pregnancy in the future by wearing an earring.
Scientists at the Georgia Institute of Technology have developed contraceptive patches which could be applied to earring backs, watches, rings or necklaces.
While contraceptive patches are already available, the team hopes incorporating them into jewellery may make them more attractive to women.
The Institute's Dr Mark Prausnitz said: "Pharmaceutical jewellery introduces a novel delivery method that may make taking contraceptives more appealing which should make it easier to remember to use it."
Dr Prausnitz said incorporating contraceptive patches into a universal earring back would allow women to use them with various different earrings.
The earring patch consists of an adhesive to hold it onto an earring back, a middle layer containing the contraceptive drug in solid form, and finally an outer layer to help the patch stick to skin.
Test patches measuring about one square centimetre and containing the hormone levonorgestrel were mounted on earring backs and applied to pig ears and hairless rats.
To simulate removal of the earrings during sleep, the researchers applied the patches for 16 hours, then removed them for eight hours.
Testing suggested that even though levels dropped while the earrings were removed, the patch could produce necessary amounts of the hormone in the bloodstream.
If the technique is used for contraception in humans, the earring back would need to be changed on a weekly basis.
Dr Prausnitz said although the technology appears to be effective, further research is needed to determine whether it would be attractive to women from different cultures.
He added: "We need to understand not only the effectiveness and economics of contraceptive jewellery, but also the social and personal factors that come into play for women all around the world.
"We would have to make sure that this contraceptive jewellery concept is something that women would actually want and use.”