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Norplant is a form of birth control developed by the Population Council that was first approved in 1983 in Finland, where it was manufactured by Leiras Oy Pharmaceuticals. The original Norplant consisted of a set of six small (2.4 mm x 34 mm) silicone capsules, each filled with 36 mg of levonorgestrel (a progestin used in many birth control pills) implanted subdermally in the upper arm and effective for five years. The original (6 capsule) Norplant's production has been phased out; USAID's contract ran until December 2006.
The original (6 capsule) Norplant was approved by the FDA in 1990 and marketed in the United States in 1991 by Wyeth Pharmaceuticals. Norplant distribution in the United States ended in 2002; limited supplies still remained in the U.S. until 2004. Norplant was withdrawn from the UK market in 1999.
Norplant II (Norplant-2, Jadelle), also developed by the Population Council and manufactured by Schering Oy, consists of two small (2.5 mm x 43 mm) silicone rods each containing 75 mg of levonorgestrel in a polymer matrix, instead of six capsules. It was approved May 31, 1996 by the FDA as being effective for 3 years; it was subsequently approved November 22, 2002 by the FDA as being effective for 5 years. Jadelle has not been marketed in the United States; Jadelle is the successor to the original Norplant in USAID's contract beginning January 2007.
Additional recommended knowledge
Norplant is implanted under the skin in the upper arm of a woman, by creating a small incision and inserting the capsules in a fanlike shape. Insertion of Norplant usually takes 15 minutes and the capsules can sometimes be seen under the skin, although usually they look like small veins. They can also be felt under the skin. Once inserted, the contraceptive works within 24 hours and lasts up to five years..
Function and effectiveness
Norplant works by preventing ovulation, which means that no eggs are released for fertilization (although it does not succeed in this 100% of the time); by thickening the mucus of the cervix, which prevents sperm from entering; and by thinning the lining of the uterus, which makes implantation of an egg less likely. Because Norplant has the potential to prevent a successful pregnancy after fertilization occurs, some consider it (and other hormonal contraception, which works in the same way) to be abortive.
The way in which Norplant causes these effects is by use of hormones. A small amount of the hormone, progestin, is released through the capsules continuously, more during the first year and a half, but then at a level similar to most contraceptive pills afterward. According to studies completed, Norplant has been shown to be 99% – 99.95% effective at preventing pregnancy, and is one of the most reliable, though not the most available, forms of birth control around. It is important that people understand Norplant, however, does not protect against sexually transmitted diseases.
Norplant should not be used in women with liver disease, breast cancer, or blood clots. Women who believe they may already be pregnant or those with vaginal bleeding should first see a physician. However, since Norplant does not contain estrogen like some birth control pills, older women, women who smoke, and women with high blood pressure are not restricted from using the system.
After three months of using Norplant, women will need to schedule a follow-up appointment to monitor blood pressure and discuss any concerns. Side effects may include irregular menstrual periods for the first approximately three months, including periods lasting longer than normal, bleeding or spotting between periods, heavy bleeding, or going with no period for the mentioned period of time. Common side effects include weight gain, nervousness, anxiety, nausea, vomiting, mastalgia, dizziness, dermatitis/rash, hirsutism, scalp-hair loss, headache, depression, and acne. Sometimes, pain, itching or infection at the site of the implant will occur. Ovarian cysts may also occur, but usually do not require treatment, although they can cause pain even if benign.
Norplant can be removed at any time by creating a second incision and withdrawing the capsules. Norplant is normally removed when the five year period is over and reinsertion of a new set is preferred, or if:
Removal can be uncomplicated, but removal difficulties have been reported with a frequency of 6.2%, based on 849 removals. Removal difficulties include: multiple incisions, capsule fragments remaining, pain, multiple visits, deep placement, lengthy removal procedure, or other.
Norplant discontinued in the United States
By 1996, more than 50,000 women had filed lawsuits, including 70 class actions, against Wyeth and/or its subsidiaries, or doctors who prescribed Norplant. Wyeth never lost a Norplant lawsuit. 
On August 26, 1999, after winning 3 jury verdicts, 20 pretrial summary judgments and the dismissal of 14,000 claims, Wyeth offered out-of-court cash settlements of $1,500 each to about 36,000 women who contended that they had not been adequately warned about possible side effects of Norplant such as irregular menstrual bleeding, headaches, nausea and depression. Wyeth said that most of the plaintiffs experienced routine side effects described in Norplant's labeling information. Wyeth did not admit to any wrongdoing, saying the settlement offer "was purely a business decision," noting "our legal success has come at a steep price because lawsuits are time-consuming, expensive, and have a chilling effect on research," and that it would continue to offer Norplant and would defend "any and all new lawsuits aggressively."
About 32,000 women accepted the out-of-court $1,500 settlements. On August 14, 2002, Wyeth won partial summary judgment and dismissal of the claims of the 2,960 remaining plaintiffs who had not accepted Wyeth's out-of-court settlement offer.
In August 2000, Wyeth suspended shipments of Norplant in the United States because during regular quality assurance monitoring, representative samples of seven lots distributed beginning October 20, 1999 tested within product specifications, but at the lower end of the release rate specification for shelf life stability, raising concerns about those lots' contraceptive effectiveness. Wyeth recommended that women who had Norplant capsules from those lots implanted use backup contraception until they determined the clinical relevance of the atypically low levels of levonorgestrel release.
On July 26, 2002, Wyeth announced that data from investigations conducted in women with Norplant capsules from the suspect lots did not suggest less contraceptive effectiveness than that reported in clinical trials, and that therefore backup contraception could be safely discontinued. Wyeth also announced that due to limitations in product component supplies, they did not plan to resume marketing the six-capsule Norplant system in the United States.
|This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Norplant". A list of authors is available in Wikipedia.|