Levonorgestrel-releasing implant

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Norplant / Jadelle
Background
TypeHormonal
Progestogen implant
First use1983 (Finland)
Failure rates (first year)
Perfect use0.05%
Typical use0.05%
Usage
Duration effect5 years
ReversibilityProvided correctly inserted
User remindersFollowing product discontinuation, alternative method required after 5 years
Clinic review3 months following insertion
Advantages and disadvantages
STI protectionNo
WeightNo proven effect
Period disadvantagesInitial irregular light spotting
BenefitsNo further user contraceptive action needed
Medical notes
Possible scarring and difficulty in removal

Norplant is a form of birth control developed by Sheldon J. Segal and Horatio B. Croxatto at the Population Council beginning in 1966, with the first clinical trial in Chile in 1974.[1][2][3] It was first approved in Finland on November 23, 1983, where it was manufactured by Leiras Oy Pharmaceuticals.[4] The original Norplant consisted of a set of six small (2.4 mm × 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.[5] The original (six capsule) Norplant's production has been phased out; USAID's contract ran until December 2006.[6]

The original (six capsule) Norplant was approved by the U.S. Food and Drug Administration (FDA) on December 10, 1990, and marketed in the United States in 1991 by Wyeth Pharmaceuticals.[7] 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 Norplant was withdrawn from the UK market in 1999.[8]

Norplant II (Norplant-2, Jadelle), also developed by the Population Council and manufactured by Schering Oy, consists of two small (2.5 mm × 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 three years; it was subsequently approved November 22, 2002 by the FDA as being effective for five years. Jadelle has not been marketed in the United States;[9] Jadelle is the successor to the original Norplant in USAID's contract beginning January 2007.[10]

Insertion

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, 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 embryo less likely.

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.

Like all hormonal contraception, Norplant does not protect against sexually transmitted infections.

Contraindications

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.

Side effects

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. There are also rare instances of stroke and heart attack. Some people experience pain and infection at the area where Norplant was inserted.

Removal

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, or if:

  • Pregnancy is desired
  • Different birth control is preferred
  • Complications arise

Normally removal is not complicated; 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.[11]

If desired, a new implant can be inserted at the time of removal.

Availability

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.[dead link][12] Wyeth never lost a Norplant lawsuit, even in cases which came before a jury.[13]

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 contest "any and all new lawsuits aggressively."[14][15]

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.[16]

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.[17]

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.[18]

New Zealand

Jadelle will be subsidized for use in New Zealand by government medical body PHARMAC from August 2010. Medical professionals raised concerns during a consultation process indicating preference for a product which is easier to insert. The agreement between Bayer New Zealand and PHARMAC was conditional on Bayer New Zealand providing adequate training to ensure doctors are comfortable in the insertion and removal technique. [19] The consultation process is not public and it is unclear if this addresses the concerns raised. Medical professionals also suggested follow up. PHARMAC will 'suggest' this to the manufacturer.

Use in the developing world

Despite its discontinuation in the US and the West, Norplant is still used in the developing world. According to one study 6.2 out of 100 rural women interviewed in one region in Bangladesh use the device, according to the United Nations Population Fund.[citation needed] The Bangladesh Fertility Research Program (BFRP) also used Norplant in an attempt for population control.

Indonesia, the country with one of the largest populations in the world, was one of the first countries to use Norplant. The Indonesian government dispensed Norplant at a high rate to decrease population growth. However, this led to a decrease in citizen's rights. For example, in Bogor, only employees who use Norplant as a method of contraceptive received their paychecks on time while other jobs required proof of Norplant use.

Norplant and other implantable contraceptives are especially effective in the developing world, as they do not require daily administration or access to a hospital to be effective. In addition, no continual contraceptive supplies (pills, condoms, etc.) are necessary, and it is a highly effective, low cost contraceptive over the long term.

References

  1. ^ Subcommittee for Workshop on Implant Contraceptives, Committee on Contraceptive Research and Development, Division of Health Policy, Institute of Medicine (March 9, 1998). "Appendix B: Norplant: historical background". In Harrison, Polly F.; Rosenfield, Allan (eds.). Contraceptive research, introduction, and use: lessons from Norplant. Washington, D.C.: National Academy Press. pp. 107–114. ISBN 978-0-309-05985-5. {{cite book}}: |author= has generic name (help); External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)CS1 maint: multiple names: authors list (link)
  2. ^ Sivin, Irving; Nash, Harold; Waldman, Sandra (February 28, 2002). "Development and introduction of contraceptive implants". Jadelle® levonorgestrel rod implants: a summary of scientific data and lessons learned from programmatic experience (PDF). New York, N.Y.: Population Council. pp. 1–6. ISBN 0-87834-105-6.
  3. ^ Gunardi, Eka Rusdianto; Affandi, Biran; Muchtar, Armen (January 2011). "Monoplant® the Indonesian implant: the overview of implant and its development". Indoesian Journal of Obstetrics and Gynecology. 35 (1): 40–46. ISSN 0303-7924.
  4. ^ Roy, Subir (1985). "Current status of Norplant subdermal implants for contraception". In Runnebaum, Benno; Rabe, Thomas; Kiesel, Ludwig (eds.). Future aspects in contraception: proceedings of an international symposium held in Heidelberg, 5–8 September 1984; Part 2, Female contraception. Boston, Mass.: MTP Press. pp. 95–106. ISBN 0-85200-906-2. The Finnish National Board of Health approved the NORPLANT sub-dermal implant system as a contraceptive method in Finland on 23 November 1983. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
  5. ^ Norplant
  6. ^ CCP: Pearl of the Week
  7. ^ Grimes, William. "Sheldon J. Segal, Who Developed Contraceptives, Dies at 83", The New York Times, October 20, 2009. Accessed October 22, 2009.
  8. ^ "Contraceptive implant withdrawn". BBC News. April 30, 1999. Retrieved May 20, 2010.
  9. ^ Population Council | Jadelle Implants FAQ General Info
  10. ^ Pearl of the Week
  11. ^ Norplant side effects (Levonorgestrel (Unavailable in US)) and drug interactions - prescription drugs and medications at RxList
  12. ^ Erica Johnson (April 1, 2003). "Medical device lawsuits". CBC news.
  13. ^ http://www.arhp.org/files/ndicimplants.pdf
  14. ^ "Contraceptive Maker Wins Woman's Suit Over Side Effects". The New York Times: A.7. 1998. {{cite journal}}: Unknown parameter |month= ignored (help)
  15. ^ Morrow, David J. (1999). "Maker of Norplant Offers a Settlement in Suit Over Effects". The New York Times: A.1. {{cite journal}}: Unknown parameter |month= ignored (help)
  16. ^ Manson, Pamela (2002). "Federal Judge Dismisses Norplant Damage Claims". Texas Lawyer. Retrieved 2007-01-15. {{cite journal}}: Unknown parameter |month= ignored (help)
  17. ^ Medwatch - 2000 Safety Information
  18. ^ Update on Advisory for Norplant Contraceptive Kits
  19. ^ [1] Pharmac - Jadelle funding

External links

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