Oral contraception
At low doses, levonorgestrel is used in monophasic and triphasic formulations of combined oral contraceptive pills, with available monophasic doses ranging from 100-250 µ G, and triphasic doses of 50 µ G/75 µ G/125 µ G. At very low daily dose of 30 µ G, levonorgestrel is used in some progestogen only pill formulations.
Emergency contraception
Levonorgestrel is used in emergency contraceptive pills (ECPs), both in a combined Yuzpe regimen which includes estrogen, and as a levonorgestrel-only method. The levonorgestrel-only method uses levonorgestrel 1.5 mg (as a single dose or as two 0.75 mg doses 12 hours apart) taken within 3 days of unprotected sex, with one study indicating that beginning as late as 120 hours (5 days) after intercourse could be effective.
Intrauterine system
Levonorgestrel is the active ingredient in the Mirena & Skyla (Jaydess) intrauterine system.
Contraceptive implants
Levonorgestrel is the active ingredient in Norplant and Jadelle.
Hormone replacement therapy
Levenorgestrel is combined with 17-beta estradiol in the Climara Pro hormonal patch.

Applied in pharmaceutical field, Levonorgestrel can be used as an active ingredient in some hormonal contraceptives, including combined oral contraceptive pills, progestogen only pills, emergency contraceptive pills, intrauterine systems and contraceptive implants; Levonorgestrel is safe, tolerated and effective in emergency contraception in woman; Levonorgestrel also can be used for the treatment of menopausal and postmenopausal disorders and alone or in combination with other hormones as an oral contraceptive.

Oral contraceptives, levonorgestrel, also known as D- norethindrone, left Kanok ketone, is currently the most widely used oral contraceptives, the racemic optically active part of norethindrone, the activity ratio norethindrone strong double dose can be reduced by half, adverse reactions are also reduced accordingly. Rapid oral absorption, 0.5 ~ 1h, reached the peak. t1 / 2 of 10 ~ 24h.Protein binding rate of 93% to 95%, bioavailability, mainly located in the liver, kidney, ovarian and uterine body's organs and tissues, and its metabolites, mainly in the form of glucuronide and sulfate salts from the urine and feces in vitro. And ethinyl estradiol combination as a short-acting oral contraceptives. Its dual photo and three photo adverse reactions less, closer to women's normal hormone secretion type. Women can be used for emergency contraception, namely failure (condom slippage or breakage, coitus out of control, rhythm miscalculation, etc.) in the same room of post-coital contraception measures unprotected intercourse or other contraceptive methods.