Etonogestrel birth control implants , sold under the Nexplanon trademarks among others, are devices made from a single stem containing etonogestrel used for birth control. This is one of the most effective forms of birth control with a one-year failure rate of about 0.05%. The device is placed under the skin and lasts at least three years. After the transfer of fertility quickly returns.
Side effects include no menstrual period, which occurs in about one-third of women. Otherwise, side effects may include irregular but generally slight bleeding. In those who are overweight the previous replacement may be required. This is not recommended in people with liver disease. The etonogestrel implant is a type of long-term reversible birth control. It works by stopping ovulation, thickening the mucus around the opening of the cervix, and changing the lining of the uterus.
Etonogestrel implants were approved for medical use in Indonesia in 1998 and in the United States in 2006. This is a List of Essential Medicines of the World Health Organization, the most effective and safe medicines needed in the health system. The cost of wholesale in developing countries is about 8.93 to 13.29 USD. In the United Kingdom the cost of the NHS device is around 83.43 pounds. The cost in the United States is about 625.00 USD. Etonogestrel implants are approved in more than 90 countries and used by approximately three million women globally by 2010.
Video Etonogestrel birth control implant
Effectiveness
Nexplanon and Implanon are a type of reversible long-acting contraceptive, which has proven to be the most effective form of birth control. Implanon failure rate is 0.05% for perfect use and typical use because this method does not require user action after insertion. A prospective follow-up study of Implanon, which included more than 2,467 women-years of exposure, found no pregnancy. Other studies have found some failures with this method, some associated with failure of the method itself and others for improper placement, drug interactions, or conceptions prior to method insertion.
By comparison, tubal sterilization has a 0.5% failure rate and an IUD has a failure rate of 0.2-0.8%. These statistics show that Implanon and Nexplanon are almost ten times more effective in preventing pregnancy than tubal sterilization. Also, tubal sterilization is permanent, whereas subdermal implants are completely reversible, should be replaced every three years.
Maps Etonogestrel birth control implant
Side effects
Irregular bleeding and spotting: Many women will experience some type of irregular, unpredictable, prolonged, frequent, or rare bleeding when using Nexplanon or Implanon. Some women also have amenorrhea. For some women, prolonged bleeding will decrease after the first three months of use. However, other women may experience this pattern of bleeding for three years of use. While these patterns are harmless, they are the most common reason women give to stop using implants. After the lifting, the bleeding pattern returns to the previous pattern in most women.
Insertion complications : Some minor side effects such as bruising, skin irritation, or pain around the site of insertion are common. However, there are some rare complications that can occur, such as infection or expulsion. In some cases, serious complications occur when the provider fails to insert, and the sticks are left in the inserter. A study in Australia reported 84 pregnancies as a result of the failure.
Migration : Although very rare, stems can sometimes move slightly in the arm. This can make deletion more difficult. It is possible that the insertion of Implanon or Nexplanon on the same site as the previous implant increases the likelihood of migration. Implanon rods can only be found through ultrasound or magnetic resonance imaging (MRI) of high frequency. Nexplanon can be found using traditional X-rays or CT scans due to the entry of barium sulfate. There are rare reports of Nexplanon implants after reaching the lungs through the pulmonary artery. Proper subdermal installation reduces the risk of this incident.
Possible weight gain : Some women may experience slight weight gain while using the implant. However, current studies are not conclusive because they do not compare the weight of women using Implanon/Nexplanon with a control group of women who do not use implants. The average increase in body weight in the study was less than 5 pounds (2.25 kg) for 2 years.
Ovarian cyst : A small proportion of women using Implanon/Nexplanon and other contraceptive implants develop ovarian cysts. Usually this cyst will disappear without treatment.
Drug interactions : It is possible that the implant has a drug interaction similar to that of combined oral contraceptives. However, drug interactions with Implanon/Nexplanon have not been systematically investigated.
Pregnancy : it is recommended that Implanon or Nexplanon be removed if pregnancy does occur. However, there is no evidence to suggest that the implant has a negative effect on a developing pregnancy or fetus.
Acne : Acne has been self-reported as a side effect of Implanon, and is listed as a side effect by the FDA. However, a study of Implanon users found that the majority of users with acne prior to their insertion reported that their acne had decreased, and only 16% of those who did not have acne before the insertion developed acne.
Other possible symptoms : Other symptoms that have been reported in Implanon or Nexplanon clinical trials include headaches, unstable emotions, abdominal pain, loss of libido, and vaginal dryness. However, no studies have conclusively determined that these symptoms are caused by implants.
Contraindications
Women should not use Implanon or Nexplanon if they:
- Whether, or think they are, pregnant
- allergic to etonogestrel
- Have unexplained vaginal bleeding
- Whether to breastfeed in the first 6 weeks postpartum (see note)
- Has severe liver disease
- Using IUD
There are some concerns about women developing ischemic heart disease, migraine with aura (spots or zig zag lines in vision), or stroke when using progestogen only contraceptives such as progestogen alone (POP) pills, injectable depo medroxyprogesterone acetate (DMPA) , and implants. However, these concerns are less for implants and POP and more for DMPA injection.
Implanon has also been shown to induce mild insulin resistance although its effects are not clinically relevant for healthy women.
Note: There is no study to provide direct evidence that progestogen contraceptives such as implants have a negative effect on breast milk or infant production. WHO and CDC register breastfeeding under 4 weeks as category 2 concerns where benefits outweigh the risks, and do not mention risks after 4 weeks postpartum.
Unlike oral contraceptives the combination of the etonogestrel contraceptive pill is not contraindicated in women with a history of past breast cancer because the pills do not contain estrogen (the cause of metaplastic changes in some breast cancers).
A complete list of contraindications can be found at WHO Medical Feasibility Criteria for Contraceptive Use 2009 and CDC US Medical Feasibility Criteria for Contraceptive Use 2010
Device description
Nexplanon/Implanon consists of a single rod made of ethylene vinylacetate copolymer with a length of 4 cm and a diameter of 2 mm. It's similar to a matchstick in size. The stem contains 68 mg of etonogestrel (sometimes called 3-keto-destrogestrel), a type of progestin. The concentration of peak serum etonogestrel was found to be 781-894 pg/mL in the first few weeks, gradually decreasing to 192-261 pg/mL after 1 year, 154-194 pg/mL after 2 years, and 156-177 pg/mL after 3 years, maintaining suppression of ovulation and contraceptive efficacy. Serum levels remained relatively stable for 36 months, implying that this method may be effective for more than 3 years.
Although not officially approved by the manufacturer for more than 3 years, none of the 240 women in 3 studies became pregnant in the 4th year.
This is a type of progestogen only contraceptive.
Insertion and deletion
An experienced doctor should insert Nexplanon or Implanon to ensure proper insertion and minimize the risk of nerve damage or misplacement, which can lead to pregnancy. Before insertion, the arms are washed with a cleaning solution and local anesthesia is applied to the upper arm around the insertion area. Needle-like applicators are used to insert stems under the skin to subdermal tissues on the inner side of the arm between the biceps and the triceps. The average time for insertion is 0.5 to 1 minute. The bandage should be kept in place of insertion for 24 hours afterwards. Bruising and mild discomfort often occur after insertion. Complications of serious insertion sites such as infections can occur very rarely, 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 contraceptive methods of contraception (such as condoms, female condoms, diaphragms, sponges, or emergency contraception) for the next week after insertion to prevent pregnancy. However, if the implant is inserted during the first five days of the woman's period, it is protected for that cycle and so on.
Nexplanon and Implanon should be removed after three years; However, they can be removed at any time if the pregnancy is desired. The stem should also be issued by an experienced physician. Upon lifting, local anesthesia is used again around the implanted area at the distal end. If the provider can not feel the implant, an imaging test may be necessary to locate the trunk before it can be removed. Small incisions are made in the skin over the tip of the implant site. In some cases, the fibrous sheath may form around the implant, in which case the sheath must be incised. Implants are removed using forceps. The removal procedure lasts, on average, 3 to 3.5 minutes.
Fertility after deletion
Within a week of removal, hormones from the device leave the body and etonogestrel undetected in most users. Most women will start ovulating within six weeks of appointment. The fertility rate will return as before the insertion of Nexplanon or Implanon.
Action mechanism
The mechanism of progestin-only contraceptive action depends on progestin and dose activity. Single-dose progestin contraceptives, such as Nexplanon or Implanon (and Cerazette's only progestin pills) allow some follicular development but inhibit ovulation in almost all cycles as the main mechanism of action. Ovulation is not observed in studies on Implanon in the first two years of use and rarely in the third year without pregnancy. The secondary work mechanism is a progestogenic increase in cervical mucus viscosity that inhibits sperm penetration. Hormonal contraceptives also have effects on the endometrium that could theoretically affect implantation, but there is no scientific evidence to suggest that implantation prevention actually comes from its use.
History
The possibility of subdermal contraceptive implants was initiated when silicon was discovered in the 1940s and found to be compatible with the human body. In 1964, Folkman and Long published the first study to show that such stems could be used to deliver drugs. In 1966, Dziuk and Cook published a study that looked at discharge rates and suggested that the stem could be suitable for contraception. After a study using implants with progestogen for contraception, the Population Council developed and patented Norplant and Jadelle. Norplant has six rods and is considered a first generation implant. Jadelle (Norplant II) and other single stem implants followed were developed due to complications resulting from the Norplants 6 trunk system. The Jadelle system contains two silicon strands mixed with levonorgestrel. In 1990 De Nijs patented the co-axial extrusion technique of ethylene vinylacetate and 3-keto-desogestrel (etonogestrel) copolymers for the preparation of long-term contraceptives, such as Implanon, Nexplanon and Nuvaring. The single stem is less visible under the skin and uses etonogestrel as opposed to levonorgestrel in the hope that it will reduce the side effects.
Norplant was used internationally starting in 1983 and marketed in the United States and Britain in 1993. There were many complications associated with the insertion and removal of Norplant in the United States and it was taken off the market in 2002. Although Jadelle was approved by the FDA, it had never been marketed in the United States, but is widely used in Africa and Asia. Implanon was first used in Indonesia in 1998 and approved for use in the United States in 2006. Nexplanon was developed to eliminate the problem of non-insertion and localization of Implanon by changing the inserter device and making radiopaque rods. Nexplanon has replaced Implanon in the UK due to the wrong insertion case. As of January 2012, Implanon is no longer marketed in the US, and Nexplanon is the only single trunk implant available.
Type
Nexplanon and Implanon NXT are essentially identical to Implanon except Nexplanon and Implanon NXT have 15 mg of barium sulfate added to the core, so it can be detected with x-rays. Nexplanon/Implanon NXT also has pre-loaded applicators for easier insertion.
References
External links
- Nexplanon
- Implanon's official website
Source of the article : Wikipedia
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