Contraceptive implant

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Contraceptive implant
Implanon 01.jpg
Container/applicator for Nexplanon, an example of an etonogestrel-based contraceptive implant
Background
Type Long-acting reversible contraception
First use?
Trade names Implanon/Nexplanon, Jadelle
Failure rates (first year)
Perfect use0.05% [1] [2]
Typical use0.05% [1] [2]
Usage
Duration effect3–5 years
User remindersNone
Advantages and disadvantages
STI protectionNo protection

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.

Contents

Women

Insertion of a contraceptive implant into a woman's arm
Removal of a contraceptive implant from a woman's arm

Implant

The contraceptive implant is hormone-based and highly effective, approved in more than 60 countries and used by millions of women around the world. The typical implant is a small flexible tube measuring about 40 mm (1.6 in) in length. It is most commonly inserted subdermally in the inner portion of the upper, non-dominant arm by a trained and certified health care provider. [3] After insertion, it prevents pregnancy by releasing progestin which inhibits ovulation. [3] [4] The two most common versions are the single-rod etonogestrel implant and the two-rod levonorgestrel implant. [5] Brands include: Norplant, Jadelle (Norplant II), Implanon, Nexplanon, Sino-implant (II), Zarin, Femplant and Trust.

Benefits

Some brands of the contraceptive implant, including Nexplanon, are over 99% effective. [6] Benefits of the implant for some include fewer, lighter periods, improved symptoms of premenstrual syndrome, long-lasting up to three to five years, smoker- and breastfeeding-safe, and the convenience of not needing to remember to use it every day. The implant is also useful for women who cannot use contraception that contains oestrogen. The implant can also be removed at any time and natural fertility will return very quickly. [7]

Side effects

When the implant is first inserted, it is common to have some bruising, tenderness or swelling around the implant. [7] In some cases, adverse effects do occur, the most common being irregular bleeding or amenorrhea. [3] Although irregularity in bleeding can be troublesome for some women, this also allows for use in treatment of dysmenorrhea, menorrhagia, and endometriosis. [3] Less common symptoms include change in appetite, depression, moodiness, hormonal imbalance, sore breasts, weight gain, dizziness, pregnancy symptoms, and lethargy. [8] [9] Although rare, there is also a risk of complications occurring during insertion or removal of the implant. [3] In rare cases, the area of skin where the implant has been inserted can become infected, which can require antibiotics. [7]

The Implanon is a 4-5 cm long arm implant. Implanon 04.jpg
The Implanon is a 4–5 cm long arm implant.

Most commonly reported from the levonorgestrel-releasing intrauterine system LNG-IUG contraceptive; breast tenderness, headaches, swelling, and skin irritation. [10] contraceptive also corresponds with earlier waking, frequent mood swings, impaired concentration, and strain. [10] Irregular vaginal uterus lining shedding is a common pattern with Norplant users; if this occurs it will be seen during the first 60 days of use but it can subside or disappear over time. [11] The Implanon also has these negative side effects causing a considerable amount of vaginal bleeding irregularities, and amenorrhea in about 30–40% of its users during the following 90 days of starting use. [11]

Postpartum use

With regard to helping women space their pregnancies appropriately, there is some debate about the most effective time to insert contraceptive implants after pregnancy. However, there may be little or no difference between immediate and delayed insertion in terms of continued use of implants at six months or in terms of women's satisfaction. [12] Progestin containing implants (specifically etonogestrel) are safe for immediate insertion in both postpartum individuals and those post-abortion. [3]

Intrauterine device

An intrauterine device (IUD) is a small contraceptive device, often T-shaped, which is implanted into the uterus. They can be hormonal or non-hormonal are long-acting, reversible, and the most effective types of reversible birth control. [13] As of 2011, IUDs are the most widely used form of reversible contraception worldwide. [14] Among types of birth control they, along with birth control implants, result in the greatest satisfaction among users. [15] IUDs also tend to be one of the most cost-effective methods of contraception for women. [16] Cons of intrauterine devices, similarly to implants, is the need for a trained healthcare professional for both insertion and removal.

Brands include: Paragard, Kyleena, Liletta, Mirena, and Skyla. [17]

Hormonal IUD

Hormonal IUDs contain the hormone levonorgestrel which is a progestin. Most commonly, products are inserted for 5 years, allowing them to release a low dose of hormones over that time frame. [3] The mechanism of action of both hormonal and non-hormonal IUDs is similar, plus the additional benefit of progestin causing a thickening of the cervical mucus. [18]

The levonorgestrel IUD is highly efficacious and has a failure rate of only 0.2% in the first year of use. [19] An additional benefit of hormonal IUDs is decreased blood loss, which 20-30% of patients will experience amenorrhea. [3] Within 1–3 months of removing the intrauterine device, however, patients should experience a return to their normal menstrual cycle. [3] The most common side effect of levonorgestrel containing IUDs is spotting during the first 3 months. [3]

Use in patients immediately postpartum can be discussed but the greater potential for expulsion and perforation must be carefully considered. [3]

Non-hormonal IUD

Non-hormonal IUDs, also known as copper IUDs, are a hormone-free option of contraception available and work by two main mechanisms of action. They are thought to slow the rate at which sperm reaches the fallopian tubes or decreases fertilization of the egg. [18] An increase of copper ions, along with other cells and enzymes, is what affects functioning of the sperm and the prevention of pregnancy. [18]

Although they do have a higher risk of pregnancy compared to hormonal IUDs, failure rates with the copper IUD are still only approximately 0.8%. [19] They also provide protection from anywhere between 2.5 to 10 years depending on the brand and manufacturer. [18] Potential adverse effects of copper IUDs include heavier menses and increased menstrual cramping. [18]

Copper IUDs have the ability to be inserted anywhere from 10 minutes to 48 hours postpartum. [20] The disadvantage of this immediate insertion is the associated higher risk of expulsion or uterine perforation, however, the benefits greatly outweigh any potential risk. [20] They also are safe to use in lactation. [20]

An additional benefit of copper IUDs is their use in emergency contraception. Not only are they able to be used as a form of emergency contraception but a Cochrane review noted that they are the most effective method of emergency contraception as well. [18] When inserted within 7 days of unprotected intercourse, they are able to reduce the risk of pregnancy by 99% and provide the added benefit of ongoing contraception in the patient too. [18]

Men

Several barriers exist to expanding research into implantable and other contraceptive methods for men, including vague regulatory guidelines, long device development timelines, men's attitudes towards convenience, and a significant lack of funding. [21] [22] [23] Several implantable devices have been attempted, both hormonal and non-hormonal.

Research

In 2001, Dutch pharmaceutical company Organon announced clinical trials of its implantable etonogestrel-based male contraceptive would begin in Europe and the U.S., anticipating a marketable product as early as 2005. [24] [25] Despite promising results, research development stopped, with outside speculation that lack of marketability was a factor. Organon representative Monique Mols stated in 2007 that "[d]espite 20 years of research, the development of a [hormonal] method acceptable to a wide population of men is unlikely". [26] Schering/Bayer had been working on a similar annual implant with quarterly injections but cancelled the research in 2006/2007, [26] declaring that men would most likely view it as "not as convenient as a woman taking a pill once a day." [23]

In 2005, a collaboratory project led by the Population Council, the University of California, Los Angeles, and the Medical Research Council began researching a matchstick-sized implant that contains MENT (7α-methyl-19-nortestosterone or trestolone), a "synthetic steroid that resembles testosterone." [27] Clinical trials were set to begin in 2011 or 2012, [21] and the project was ongoing as of 2016, with hopes of gaining approval as the first reversible male contraceptive. [27]

In 2006, Shepherd Medical Company received FDA approval for a clinical trial of its non-hormonal implant called an intra vas device (IVD), which consists of two plugs that block sperm flow in the vas deferens. Working on the success of its pilot study and solid results from its clinical trials, the company announced it would expand its trials to three U.S. cities later that year. Questions remained about how reversible the procedure would be in the long-term; however, it was expected to be more reversible than a vasectomy. In 2008, the company disbanded due to the economic crisis but has stated it would restart its research with proper funding. [28] [29] [30]

In January 2016, news broke of a non-hormonal, implantable valve—the Bimek SLV. It included a switch that attaches to the vas deferens, allowing the owner to stop and resume the flow of sperm on demand. A clinical trial of 25 participants was announced to further test the efficacy of the device. [31] [32]

Other animals

Implantable contraception is also an option for animals, particularly for animal managers at zoos and other captive animal facilities who require reversible contraception methods for managing population growth in limited captive habitat. [33] The Association of Zoos and Aquariums' (AZA) Reproductive Management Center (formerly known as the AZA Wildlife Contraception Center) at the Saint Louis Zoo in St. Louis, Missouri, has played a major role in researching and disseminating contraception information, via its Contraception Database. It houses over 30,000 records for hundreds of species. [33] [34] One of the most popular contraceptive methods used by zoos (as well as in domestic animals) is the melengestrol acetate (MGA) implant, a progestin-based hormonal contraceptive developed in the mid-1970s. Other progestin-based implants that have been placed in animals include Norplant, Jadelle, and Implanon. Androgen-based implants that use agonist (stimulating) gonadotropin-releasing hormone (GnRH) and, to a lesser degree, IUDs have also seen use in several domestic and exotic species. Whatever the implant, some care must be taken to minimize the risk of implant migration or loss. [33] [35] [36]

Related Research Articles

<span class="mw-page-title-main">Copper IUD</span> Birth control and emergency contraceptive device

A copper intrauterine device (IUD), also known as an intrauterine coil or copper coil or non-hormonal IUD, is a type of intrauterine device which contains copper. It is used for birth control and emergency contraception within five days of unprotected sex. It is one of the most effective forms of birth control with a one-year failure rate around 0.7%. The device is placed in the uterus and lasts up to twelve years. It may be used by women of all ages regardless of whether or not they have had children. Following removal, fertility quickly returns.

<span class="mw-page-title-main">Emergency contraception</span> Birth control measures taken after sexual intercourse

Emergency contraception (EC) is a birth control measure, used after sexual intercourse to prevent pregnancy.

<span class="mw-page-title-main">Levonorgestrel</span> Hormonal medication used for birth control

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.

<span class="mw-page-title-main">Hormonal intrauterine device</span> Intrauterine device

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.

Gräfenberg's ring is a flexible ring of silk suture, later versions of which were wrapped in silver wire. It was an early IUD, a birth control device. Gräfenberg's ring was the first IUD used by a significant number of women. The ring was introduced by German gynecologist Ernst Gräfenberg in 1929. It ceased to be in wide use circa 1939.

<span class="mw-page-title-main">Vaginal ring</span>

Vaginal rings are polymeric drug delivery devices designed to provide controlled release of drugs for intravaginal administration over extended periods of time. The ring is inserted into the vagina and provides contraception protection. Vaginal rings come in one size that fits most women.

<span class="mw-page-title-main">Hormonal contraception</span> Birth control methods that act on the endocrine system

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.

<span class="mw-page-title-main">Etonogestrel</span> Chemical compound

Etonogestrel is a medication which is used as a means of birth control for women. 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. 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. Following removal, fertility quickly returns.

<span class="mw-page-title-main">Beginning of pregnancy controversy</span> Cultural-linguistic, not scientific question

Controversy over the beginning of pregnancy occurs in different contexts, particularly as it is discussed within the debate of abortion in the United States. Because an abortion is defined as ending an established pregnancy, rather than as destroying a fertilized egg, depending on when pregnancy is considered to begin, some methods of birth control as well as some methods of infertility treatment might be classified as causing abortions.

<span class="mw-page-title-main">Comparison of birth control methods</span>

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.

Long-acting reversible contraceptives (LARC) are methods of birth control that provide effective contraception for an extended period without requiring user action. They include injections, intrauterine devices (IUDs), and subdermal contraceptive implants. They are the most effective reversible methods of contraception because their efficacy is not reliant on patient compliance. The typical use failure rates of IUDs and implants, less than 1% per year, are about the same as perfect use failure rates.

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:

<span class="mw-page-title-main">Birth control</span> Method of preventing human pregnancy

Birth control, also known as contraception, anticonception, and fertility control, is the use of methods or devices to prevent unintended pregnancy. Birth control has been used since ancient times, but effective and safe methods of birth control only became available in the 20th century. Planning, making available, and using human birth control is called family planning. Some cultures limit or discourage access to birth control because they consider it to be morally, religiously, or politically undesirable.

Sex after pregnancy is often delayed for several weeks or months, and may be difficult and painful for women. Painful intercourse is the most common sexual activity-related complication after childbirth. Since there are no guidelines on resuming sexual intercourse after childbirth, the postpartum patients are generally advised to resume sex when they feel comfortable to do so. Injury to the perineum or surgical cuts (episiotomy) to the vagina during childbirth can cause sexual dysfunction. Sexual activity in the postpartum period other than sexual intercourse is possible sooner, but some women experience a prolonged loss of sexual desire after giving birth, which may be associated with postnatal depression. Common issues that may last more than a year after birth are greater desire by the man than the woman, and a worsening of the woman's body image.

Sheldon Jerome Segal was an American embryologist and biochemist who spent his entire career working on contraception, and made major innovations in the field of long-lasting alternatives, with Chilean physician Horacio Croxatto, including in the creation of Norplant, the first major development advance in birth control since the birth control pill.

<span class="mw-page-title-main">Intrauterine device</span> Form of birth control involving a device placed in the uterus

An intrauterine device (IUD), also known as 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 one form of long-acting reversible birth control (LARC). One study found that female family planning providers choose LARC methods more often (41.7%) than the general public (12.1%). Among birth control methods, IUDs, along with other contraceptive implants, result in the greatest satisfaction among users.

Women's reproductive health in the United States refers to the set of physical, mental, and social issues related to the health of women in the United States. It includes the rights of women in the United States to adequate sexual health, available contraception methods, and treatment for sexually transmitted diseases. The prevalence of women's health issues in American culture is inspired by second-wave feminism in the United States. As a result of this movement, women of the United States began to question the largely male-dominated health care system and demanded a right to information on issues regarding their physiology and anatomy. The U.S. government has made significant strides to propose solutions, like creating the Women's Health Initiative through the Office of Research on Women's Health in 1991. However, many issues still exist related to the accessibility of reproductive healthcare as well as the stigma and controversy attached to sexual health, contraception, and sexually transmitted diseases.

There are many types of contraceptive methods available in France. All contraceptives are obtained by medical prescription after a visit to a family planning specialist, a gynecologist or a midwife. An exception to this is emergency contraception, which does not require a prescription and can be obtained directly in a pharmacy.

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.

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