Clinical data | |
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Trade names | Circlet, Implanon, Nexplanon, others |
Other names | ORG-3236; SCH-900702 (with EE ); 3-Ketodesogestrel; 3-Oxodesogestrel; 11-Methylenelevonorgestrel; [1] 11-Methylene-17α-ethynyl-18-methyl-19-nortestosterone; 11-Methylene-17α-ethynyl-18-methylestr-4-en-17β-ol-3-one |
AHFS/Drugs.com | Professional Drug Facts |
MedlinePlus | a604032 |
Pregnancy category |
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Routes of administration | Subcutaneous implant, vaginal ring |
Drug class | Progestogen; Progestin |
ATC code | |
Legal status | |
Legal status | |
Pharmacokinetic data | |
Bioavailability | Implant: 100% [4] Vaginal ring: 100% [5] |
Protein binding | ≥98% (66% to albumin, 32% to SHBG ) [4] |
Metabolism | Liver (CYP3A4) [4] [5] |
Elimination half-life | 21–38 hours [6] [7] [4] [5] |
Excretion | Urine (major), feces (minor) [4] [5] |
Identifiers | |
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CAS Number | |
PubChem CID | |
IUPHAR/BPS | |
DrugBank | |
ChemSpider | |
UNII | |
KEGG | |
ChEBI | |
ChEMBL | |
CompTox Dashboard (EPA) | |
ECHA InfoCard | 100.053.561 |
Chemical and physical data | |
Formula | C22H28O2 |
Molar mass | 324.464 g·mol−1 |
3D model (JSmol) | |
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Etonogestrel birth control implant | |
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Background | |
Type | Hormonal Progestin-only implant |
First use | 1998 Indonesia |
Synonyms | Etonogestrel contraceptive implant |
Trade names | Implanon, Nexplanon, others |
AHFS/Drugs.com | FDA Professional Drug Information |
Failure rates (first year) | |
Perfect use | 0.05% [8] |
Typical use | 0.05% [8] |
Usage | |
Duration effect | 3 to 5 years [9] [10] |
Reversibility | Yes |
User reminders | Requires removal after the 3–5 years [11] |
Advantages and disadvantages | |
STI protection | No |
Weight | May cause weight gain |
Period disadvantages | May cause irregular or prolonged bleeding |
Period advantages | Minimizes pain. In 33% no periods. |
Benefits | Long-term contraception. |
Etonogestrel is a medication which is used as a means of birth control for women. [4] [5] [12] [13] It is available as an implant placed under the skin of the upper arm under the brand names Nexplanon and Implanon. It is a progestin that is also used in combination with ethinylestradiol, an estrogen, as a vaginal ring under the brand names NuvaRing and Circlet. [14] Etonogestrel is effective as a means of birth control and lasts at least three or four years with some data showing effectiveness for five years. [9] [11] Following removal, fertility quickly returns. [15]
Side effects of etonogestrel include menstrual irregularities, breast tenderness, mood changes, acne, headaches, Marca da besta epanom, and others. [4] Etonogestrel is a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone. [16] It works by stopping ovulation, thickening the mucus around the opening of the cervix, and altering the lining of the uterus. [17] It has very weak androgenic and glucocorticoid activity and no other important hormonal activity. [16]
Etonogestrel was patented in 1972 and introduced for medical use in 1998. [18] [19] [20] It became available in the United States in 2006. [18] [19] Etonogestrel implants are approved in more than 90 countries and used by about three million women globally as of 2010. [17] [21]
A closely related and more widely known and used progestin, desogestrel, is a prodrug of etonogestrel in the body. [16]
Etonogestrel is used in hormonal contraception in form of the etonogestrel contraceptive implant [4] and the contraceptive vaginal ring (brand names NuvaRing, Circlet), the latter in combination with ethinylestradiol. [5]
Etonogestrel birth control implants are a type of long-acting reversible contraception, which has been shown to be one of the most effective form of birth control. [22] The failure rate of the implants is 0.05% for both perfect use and typical use because the method requires no user action after placement. [23] Studies of one type, which include over 2,467 women-years of exposure, found no pregnancies. [24] [25] [26]
Other studies have found some failures with this method, some attributed to failures of the method itself and others to improper placement, drug interactions, or conception prior to method insertion. [27]
In comparison, tubal sterilization has a failure rate of 0.5% and IUDs have a failure rate of 0.2–0.8%. [23] A single implant is approved for three years with data showing effectiveness for five years. [28] [11]
Women should not use implants if they: [29]
Women should not use combined hormone contraceptives (CHC) if they have migraines with auras. [30]
A full list of contraindications can be found in the WHO Medical Eligibility Criteria for Contraceptive Use 2015 and the CDC United States Medical Eligibility Criteria for Contraceptive Use 2016.
Irregular bleeding and spotting: Many women will experience some type of irregular, unpredictable, prolonged, frequent, or infrequent bleeding. [31] Some women also experience amenorrhea. For some women, prolonged bleeding will decline after the first three months of use. However, other women may experience this bleeding pattern through all five years of use. While these patterns are not dangerous, they are the most common reason that women give for discontinuing the use of the implant. After removal, bleeding patterns return to previous patterns in most women. [24] [25] [26]
Insertion complications: Some minor side effects such as bruising, skin irritation, or pain around the insertion site are common. [24] However, there are some rare complications that can occur, such as infection or expulsion. [24] [32] In some cases, a serious complication occurs when the provider fails to insert, and the rod is left in the inserter. An Australian study reported 84 pregnancies as a result of such failure. [27]
Migration: Although very rare, the rod can sometimes move slightly within the arm. This can make removal more difficult. It is possible that insertion in the same site as a previous implant increases the likelihood of migration. [32] Rods can be located only through high-frequency ultrasound or magnetic resonance imaging (MRI). [24] It can be located using traditional X-ray or CT-scan because of the inclusion of barium sulphate. There have been rare reports of implants having reached the lung via the pulmonary artery. [33] Correct subdermal insertion over the triceps muscle reduces the risk of these events.
Possible weight gain: Some women may experience slight weight gain when using the implant. [24] However, current studies are not conclusive because they do not compare the weight of women using implants with a control group of women not using the implant. The average increase in body weight in studies was less than 5 pounds (2,25 kg) over 2 years. [25]
Ovarian cysts: A small portion of women using implants and other contraceptive implants develop ovarian cysts. [24] Usually these cysts will disappear without treatment. [34]
Pregnancy: It is recommended that implants be removed if a pregnancy does occur. However, there is no evidence to suggest that the implant has a negative effect on pregnancy or a developing fetus. [24]
Acne: Acne has been self-reported to be a side effect, and is listed as a side effect by the FDA. However, a study of users found that a majority of users with acne before their insertion reported that their acne had decreased, and only 16% of those who did not have acne before insertion developed acne. [25]
Other possible symptoms: Other symptoms that have been reported in trials of implants include headache, emotional lability, depression, abdominal pain, loss of libido, and vaginal dryness. [24] However, there have been no studies that conclusively determine that these symptoms are caused by the implant. [25] [26]
No serious side effects are expected when overdosing contraceptives in general. [35]
Efavirenz, an inducer of the liver enzyme CYP3A4, appears to decrease etonogestrel levels [36] and increase rates of undesired pregnancy among implant users.
Similar effects are expected for other CYP3A4 inducers, but it is not known whether these are clinically relevant. The opposite is true of CYP3A4 inhibitors such as ketoconazole, itraconazole and clarithromycin: they might increase etonogestrel concentrations in the body. [35]
Nexplanon/Implanon consists of a single rod made of ethylene vinylacetate copolymer that is 4 cm long and 2 mm in diameter. [31] It is similar to a matchstick in size. The rod contains 68 mg of etonogestrel (sometimes called 3-keto-destrogestrel), a type of progestin. [24] Peak serum etonogestrel concentrations have been found to reach 781–894 pg/mL in the first few weeks, gradually decreasing to 192–261 pg/mL after one year, 154–194 pg/mL after two years, and 156–177 pg/mL after three years, maintaining ovulation suppression and contraceptive efficacy. [37] Serum levels maintain relatively stable through 36 months, which implies that the method may be effective for longer than three years. [38]
Although not formally approved by the manufacturer for more than three years, studies have shown it remains a highly effective contraceptive for five years. [28]
It is a type of progestogen-only contraception.
An experienced clinician must perform the insertion of implants to ensure proper insertion and minimize the risk of nerve damage or misplacement, which could result in pregnancy. [39] Before insertion, the arm is washed with a cleaning solution and a local anesthetic is applied to the upper arm around the insertion area. [24] A needle-like applicator is used to insert the rod under the skin into the subdermal tissue on the inner side of the arm posterior to the groove between the biceps and triceps muscles. [40] The average time for insertion is 0.5 to 1 minute. [25] [26] A bandage should be kept on the insertion site for 24 hours afterwards. Bruising and mild discomfort are common after insertion. [24] Serious insertion site complications such as infection can occur very rarely, in less than 1% of patients. If a woman receives an implant outside the first five days of her period, she should wait to have sex or use a backup method of contraception (such as a condom, female condom, diaphragm, sponge, or emergency contraception) for the following week after insertion to prevent pregnancy. However, if the implant is inserted during the first five days of a woman's period, the drug typically is effective for that cycle and beyond. [41]
Implants can be removed at any time if pregnancy is desired. The rod must also be removed by an experienced clinician. At removal, a local anesthetic is again used around the implant area at the distal end. [24] If the provider cannot feel the implant, imaging tests may be necessary to locate the rod before it can be removed. A small incision is made in the skin over the end of the implant site. In some cases, a fibrous sheath may have formed around the implant, in which case the sheath must be incised. [24] The implant is removed using forceps. The removal procedure lasts, on average, 3 to 3.5 minutes. [25] [26]
Within a week of removal, the hormones from the device leave the body and etonogestrel is undetectable in most users. [24] Most women will begin to ovulate within six weeks of removal. [38] [42] Fertility levels will return to what they were before implant insertion. [15]
Nexplanon and Implanon NXT are essentially identical to Implanon except Nexplanon and Implanon NXT have 15 mg of barium sulphate added to the core, so it is detectable by x-ray. [43] [28] Nexplanon and Implanon NXT also has a pre-loaded applicator for easier insertion. [44]
The mechanism of action of progestin-only contraceptives depends on the progestin activity and dose. [45] Intermediate dose progestin-only contraceptives like Nexplanon or Implanon allow some follicular development but inhibit ovulation in almost all cycles as the primary mechanism of action. Ovulation was not observed in studies of Implanon in the first two years of use and only rarely in the third year with no pregnancies. A secondary mechanism of action is the progestogenic increase in cervical mucus viscosity which inhibits sperm penetration. [46] Hormonal contraceptives also have effects on the endometrium that theoretically could affect implantation, however no scientific evidence indicates that prevention of implantation actually results from their use. [47]
Etonogestrel is a progestogen, or an agonist of the progesterone receptor. [16] It is less androgenic than levonorgestrel and norethisterone, [48] [49] and it does not cause a decrease in sex hormone-binding globulin levels. [50] However, it is still associated with acne in up to 13.5% of patients when used as an implant, though this side effect only accounts for 1.3% of premature removals of the implant. [51] In addition to its progestogenic and weak androgenic activity, etonogestrel binds to the glucocorticoid receptor with about 14% of the affinity of dexamethasone (relative to 1% for levonorgestrel) and has very weak glucocorticoid activity. [16] Etonogestrel has no other hormonal activity (e.g., estrogenic, antimineralocorticoid). [16] Some inhibition of 5α-reductase and hepatic cytochrome P450 enzymes has been observed with etonogestrel in vitro , similarly to other 19-nortestosterone progestins. [16]
Compound | PR | AR | ER | GR | MR | SHBG | CBG |
---|---|---|---|---|---|---|---|
Etonogestrel | 150 | 20 | 0 | 14 | 0 | 15 | 0 |
5α-Dihydroetonogestrel | 9 | 17 | 0 | ? | ? | ? | ? |
Sources: Values are percentages (%). Reference ligands (100%) were prome-gestone for the PR , metribolone for the AR , E2 for the ER , DEXA for the GR , aldosterone for the MR , DHT for SHBG , and cortisol for CBG . Sources: [52] [16] |
Steroid | Class | TR (↑)a | GR (%)b |
---|---|---|---|
Dexamethasone | Corticosteroid | ++ | 100 |
Ethinylestradiol | Estrogen | – | 0 |
Etonogestrel | Progestin | + | 14 |
Gestodene | Progestin | + | 27 |
Levonorgestrel | Progestin | – | 1 |
Medroxyprogesterone acetate | Progestin | + | 29 |
Norethisterone | Progestin | – | 0 |
Norgestimate | Progestin | – | 1 |
Progesterone | Progestogen | + | 10 |
Footnotes:a = Thrombin receptor (TR) upregulation (↑) in vascular smooth muscle cells (VSMCs). b = RBA (%) for the glucocorticoid receptor (GR). Strength: – = No effect. + = Pronounced effect. ++ = Strong effect. Sources: [53] |
The bioavailability of etonogestrel when given as a subcutaneous implant or as a vaginal ring is 100%. [4] [5] Steady-state levels of etonogestrel are achieved within one week upon insertion as an implant or vaginal ring. [4] [5] The mean volume of distribution of etonogestrel is 201 L. [4] The plasma protein binding of the medication is at least 98%, with 66% bound to albumin and 32% bound to sex hormone-binding globulin. [4] [5] Etonogestrel is metabolized in the liver by CYP3A4. [4] [5] The biological activity of its metabolites is unknown. [4] [5] The elimination half-life of etonogestrel is about 25 to 29 hours. [4] [5] Following removal of an etonogestrel-containing implant, levels of the medication were below the limits of assay detection by one week. [4] The major portion of etonogestrel is eliminated in urine and a minor portion is eliminated in feces. [4] [5]
Etonogestrel, also known as 11-methylene-17α-ethynyl-18-methyl-19-nortestosterone or as 11-methylene-17α-ethynyl-18-methylestr-4-en-17β-ol-3-one, is a synthetic estrane steroid and a derivative of testosterone. [12] [14] It is more specifically a derivative of norethisterone (17α-ethynyl-19-nortestosterone) and is a member of the gonane (18-methylestrane) subgroup of the 19-nortestosterone family of progestins. [54] [55] Etonogestrel is the C3 ketone derivative of desogestrel and the C11 methylene derivative of levonorgestrel and is also known as 3-ketodesogestrel and as 11-methylenelevonorgestrel. [1]
The possibility of the subdermal contraceptive implant began when silicone was discovered in the 1940s and found to be bio-compatible with the human body. [56] In 1964, Folkman and Long published the first study demonstrating that such a rod could be used to deliver drugs. [57] In 1966 Dziuk and Cook published a study that looked at release rates and suggested that the rods could be well suited for contraception. [58] After a study that used implants with progestogens for contraception, the Population Council developed and patented Norplant and Jadelle. [59] Norplant has six rods and is considered a first-generation implant. Jadelle (Norplant II), a two-rod implant, and other single rod implants that followed, were developed because of complications resulting from Norplant's six-rod system. The Jadelle system contains two silicone rods mixed with levonorgestrel. In 1990 De Nijs patented a co-axial extrusion technique of ethylene vinylacetate copolymers and 3-keto-desogestrel (etonogestrel) for the preparation of long-acting contraceptive devices, such as Implanon, Nexplanon and Nuvaring. [60] The single rods were less visible under the skin and used etonogestrel as opposed to levonorgestrel in the hopes that it would reduce side effects. [56]
Desogestrel (3-deketoetonogestrel), a prodrug of etonogestrel, was introduced for medical use in 1981. [6] [61]
Norplant was used internationally beginning in 1983 and was marketed in the United States and the United Kingdom in 1993. There were many complications associated with Norplant removal in the United States and it was taken off the market in 2002. Although Jadelle was approved by the FDA, it has never been marketed in the United States, but it is widely used in Africa and Asia. [59]
Etonogestrel itself was first introduced as Implanon in Indonesia in 1998, [18] [19] was marketed in the United Kingdom shortly thereafter, [62] and approved for use in the United States in 2006. [18] [19] Nexplanon was developed to eliminate the problem of non-insertion and localization of Implanon by changing the inserter device and making the rod radiopaque. [43] As of January 2012, Implanon is no longer being marketed and Nexplanon is the only available single-rod implant.
Etonogestrel is the generic name of the drug and its INN , USAN , and BAN . [12] [14] It is also known by its developmental code name ORG-3236. [12] [14]
Etonogestrel is marketed under the brand names Circlet, Implanon, Nexplanon, and NuvaRing. [12] [14]
Etonogestrel is available widely throughout the world, including in the United States, Canada, the United Kingdom, Ireland, elsewhere throughout Europe, South Africa, Latin America, South, East, and Southeast Asia, and elsewhere in the world. [14]
An etonogestrel-releasing intrauterine device was under development for use as a form of birth control for women but development was discontinued in 2015. [63]
Etonogestrel has been studied for use as a potential male contraceptive. [64]
The combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as "the pill", is a type of birth control that is designed to be taken orally by women. It is the oral form of combined hormonal contraception. The pill contains two important hormones: a progestin and estrogen. When taken correctly, it alters the menstrual cycle to eliminate ovulation and prevent pregnancy.
A progestogen, also referred to as a progestagen, gestagen, or gestogen, is a type of medication which produces effects similar to those of the natural female sex hormone progesterone in the body. A progestin is a synthetic progestogen. Progestogens are used most commonly in hormonal birth control and menopausal hormone therapy. They can also be used in the treatment of gynecological conditions, to support fertility and pregnancy, to lower sex hormone levels for various purposes, and for other indications. Progestogens are used alone or in combination with estrogens. They are available in a wide variety of formulations and for use by many different routes of administration. Examples of progestogens include natural or bioidentical progesterone as well as progestins such as medroxyprogesterone acetate and norethisterone.
Levonorgestrel is a hormonal medication which is used in a number of birth control methods. It is combined with an estrogen to make combination birth control pills. As an emergency birth control, sold under the brand names Plan B One-Step and Julie, among others, it is useful within 72 hours of unprotected sex. The more time that has passed since sex, the less effective the medication becomes, and it does not work after pregnancy (implantation) has occurred. Levonorgestrel works by preventing ovulation or fertilization from occurring. It decreases the chances of pregnancy by 57–93%. In an intrauterine device (IUD), such as Mirena among others, it is effective for the long-term prevention of pregnancy. A levonorgestrel-releasing implant is also available in some countries.
Levonorgestrel-releasing implant, sold under the brand name Jadelle among others, are devices that release levonorgestrel for birth control. It is one of the most effective forms of birth control with a one-year failure rate around 0.05%. The device is placed under the skin and lasts for up to five years. It may be used by women who have a history of pelvic inflammatory disease and therefore cannot use an intrauterine device. Following removal, fertility quickly returns.
A hormonal intrauterine device (IUD), also known as an intrauterine system (IUS) with progestogen and sold under the brand name Mirena among others, is an intrauterine device that releases a progestogenic hormonal agent such as levonorgestrel into the uterus. It is used for birth control, heavy menstrual periods, and to prevent excessive build of the lining of the uterus in those on estrogen replacement therapy. It is one of the most effective forms of birth control with a one-year failure rate around 0.2%. The device is placed in the uterus and lasts three to eight years. Fertility often returns quickly following removal.
Progestogen-only pills (POPs), colloquially known as "mini pills", are a type of oral contraceptive that contain synthetic progestogens (progestins) and do not contain estrogens. They are primarily used for the prevention of undesired pregnancy, although additional medical uses also exist.
Extended or continuous cycle combined oral contraceptive pills are a packaging of combined oral contraceptive pills (COCPs) that reduce or eliminate the withdrawal bleeding that would occur once every 28 days in traditionally packaged COCPs. It works by reducing the frequency of the pill-free or placebo days. Extended cycle use of COCPs may also be called menstrual suppression, although other hormonal medications or medication delivery systems may also be used to suppress menses. Any brand of combined oral contraceptive pills can be used in an extended or continuous manner by simply discarding the placebo pills; this is most commonly done with monophasic pills in which all of the pills in a package contain the same fixed dosing of a synthetic estrogen and a progestin in each active pill.
Desogestrel is a progestin medication which is used in birth control pills. It is also used in the treatment of menopausal symptoms in women. The medication is available and used alone or in combination with an estrogen. It is taken by mouth.
Drospirenone is a progestin and antiandrogen medication which is used in birth control pills to prevent pregnancy and in menopausal hormone therapy, among other uses. It is available both alone under the brand name Slynd and in combination with an estrogen under the brand name Yasmin among others. The medication is an analog of the drug spironolactone. Drospirenone is taken by mouth.
A contraceptive vaginal ring is a type of hormonal insert that is placed in the vagina for the purpose of birth control. The rings themselves utilize a plastic polymer matrix that is inlaid or embedded with contraceptive drug. This drug, often one or two hormones, is absorbed directly through the bloodstream through the cells that line the vaginal wall. Some vaginal rings contain both an estrogen and a progestin, which are available in Europe and the United States. Other vaginal rings contain just progesterone. The progesterone-only ring is only available in Latin America, exclusively for postpartum breastfeeding parents.
Hormonal contraception refers to birth control methods that act on the endocrine system. Almost all methods are composed of steroid hormones, although in India one selective estrogen receptor modulator is marketed as a contraceptive. The original hormonal method—the combined oral contraceptive pill—was first marketed as a contraceptive in 1960. In the ensuing decades, many other delivery methods have been developed, although the oral and injectable methods are by far the most popular. Hormonal contraception is highly effective: when taken on the prescribed schedule, users of steroid hormone methods experience pregnancy rates of less than 1% per year. Perfect-use pregnancy rates for most hormonal contraceptives are usually around the 0.3% rate or less. Currently available methods can only be used by women; the development of a male hormonal contraceptive is an active research area.
There are many methods of birth control that vary in requirements, side effects, and effectiveness. As the technology, education, and awareness about contraception has evolved, new contraception methods have been theorized and put in application. Although no method of birth control is ideal for every user, some methods remain more effective, affordable or intrusive than others. Outlined here are the different types of barrier methods, hormonal methods, various methods including spermicides, emergency contraceptives, and surgical methods and a comparison between them.
Gestodene, sold under the brand names Femodene and Minulet among others, is a progestin medication which is used in birth control pills for women. It is also used in menopausal hormone therapy. The medication is available almost exclusively in combination with an estrogen. It is taken by mouth.
Progestogen-only contraception relies on progestogens alone to achieve contraception. It is one of the two major types of hormonal contraception, with the other major type being combined hormonal contraceptive methods. There are several progestogen only contraceptive methods:
A contraceptive implant is an implantable medical device used for the purpose of birth control. The implant may depend on the timed release of hormones to hinder ovulation or sperm development, the ability of copper to act as a natural spermicide within the uterus, or it may work using a non-hormonal, physical blocking mechanism. As with other contraceptives, a contraceptive implant is designed to prevent pregnancy, but it does not protect against sexually transmitted infections.
An intrauterine device (IUD), also known as an intrauterine contraceptive device or coil, is a small, often T-shaped birth control device that is inserted into the uterus to prevent pregnancy. IUDs are a form of long-acting reversible contraception (LARC).
Segesterone acetate (SGA), sold under the brand name Nestorone among others, is a progestin medication which is used in birth control and in the treatment of endometriosis. It is available both alone and in combination with an estrogen as segesterone acetate/ethinylestradiol. It is not effective by mouth and must be given by other routes, most typically as a vaginal ring or implant that is placed into fat.
Ethinylestradiol/etonogestrel, sold under the brand names NuvaRing among others, is a hormonal vaginal ring used for birth control and to improve menstrual symptoms. It contains ethinylestradiol, an estrogen, and etonogestrel, a progestin. It is used by insertion into the vagina. Pregnancy occurs in about 0.3% of women with perfect use and 9% of women with typical use.
Levonorgestrel acetate (LNG-A), or levonorgestrel 17β-acetate, also known as 3-ketonorgestimate, is a progestin which was never marketed. It is a progestogen ester and is the C17β acetate ester and a prodrug of levonorgestrel. Norgestimate is the C3 oxime of LNG-A. The drug is a minor active metabolite of norgestimate, which is a prodrug of norelgestromin and to a lesser extent of levonorgestrel and LNG-A. LNG-A has high affinity for the progesterone receptor, about 135% of that of promegestone. Along with levonorgestrel butanoate, LNG-A was investigated as a hormonal contraceptive by the Population Council.
Menstrual suppression refers to the practice of using hormonal management to stop or reduce menstrual bleeding. In contrast to surgical options for this purpose, such as hysterectomy or endometrial ablation, hormonal methods to manipulate menstruation are reversible.
The elimination half-life for 3-keto-desogestrel is approximately 38 ± 20 hours at steady state.
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: CS1 maint: location missing publisher (link)In 1981, desogestrel was marketed as a new low dose oral contraceptive under the trade names Marvelon and Desogen.32