Norplant

contraceptive

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Last updated

July 23, 2026

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Norplant was a form of contraception that utilized levonorgestrel, a synthetic progestogen. This method involved implanting six small capsules containing levonorgestrel beneath the skin of the upper arm, providing birth control for up to five years. Levonorgestrel works by inhibiting ovulation, thickening cervical mucus to block sperm, and potentially preventing implantation. While Norplant has largely been replaced by newer methods, levonorgestrel is still used in various contraceptives, including some oral contraceptives, emergency contraception (morning-after pills), and intrauterine devices (IUDs).1

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levonorgestrel
…form of contraception marketed as Norplant. In this system levonorgestrel was implanted beneath the skin of the upper arm in six Silastic (silicone-plastic) capsules, which provided birth control for five years. However, this system has been replaced by Norplant II (Jadelle), which uses a different synthetic progestogen, called etonogestrel, implanted…
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…form of contraception marketed as Norplant. In this system levonorgestrel was implanted beneath the skin of the upper arm in six Silastic (silicone-plastic) capsules, which provided birth control for five years. However, this system has been replaced by Norplant II (Jadelle), which uses a different synthetic progestogen, called etonogestrel, implanted…
Read More

contraception
Hormonal contraceptives
Norplant consists of a set of small, soft tubes that are surgically implanted under the skin of a woman’s arm, where they release the synthetic hormone progestin. Norplant can prevent conception for up to five years.
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Norplant consists of a set of small, soft tubes that are surgically implanted under the skin of a woman’s arm, where they release the synthetic hormone progestin. Norplant can prevent conception for up to five years.
Read More