Contraceptive vaginal ring

Last updated
NuvaRing
NuvaRing compressed.jpg
NuvaRing is a flexible plastic ring with both oestrogen and progesterone.
Background
TypeHormonal
First use2001
Failure rates (first year)
Perfect use0.3 for Nuvaring% [1]
Typical use1.5 to 9 for Nuvaring% [2] [1]
Usage
Duration effect4 weeks for Nuvaring, 3 months for progesterone only vaginal ring
User remindersInserted for 3 weeks and then removed for 7 days for Nuvaring
Clinic reviewAnnual
Advantages and disadvantages
STI protectionNo
WeightNo proven effect
BenefitsEasy insertion and removal

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. [3] This drug, often one or two hormones, is absorbed directly through the bloodstream through the cells that line the vaginal wall. [4] [5] Some vaginal rings contain both an estrogen and a progestin (brand names NuvaRing and Annovera), which are available in Europe and the United States. [6] [7] [8] [9] Other vaginal rings contain just progesterone (brand name Progering). [10] The progesterone-only ring is only available in Latin America, exclusively for postpartum breastfeeding parents, therefore, it is not available in the United States. [9]

Contents

The Progering is made of silicone-elastorone with an outer diameter of 58 mm and cross-sectional diameter of 8.4 mm. [10] Similarly, Annovera has an outer diameter of 56 mm and cross-sectional diameter of 8.4 mm. [7] In contrast, the Nuvaring has a diameter of 54 mm with a cross-sectional diameter that measures 4 mm. [6] The vaginal rings work as a long acting drug delivery system for varying indications, including prevention of pregnancy, improvement of dysmenorrhea and menorrhagia, lower risks of ovarian and endometrial cancers, and reduction of risk of cysts in the ovaries. [11] Although the vaginal rings do not provide protection for sexually transmitted diseases, the rings are being assessed as a possible drug delivery system for HIV prevention. [12]

Combined hormonal contraceptive vaginal ring

Mechanism of Action

The ethinylestradiol/etonogestrel vaginal ring is also known as NuvaRing. [6] It is a flexible plastic (ethylene-vinyl acetate copolymer) ring that releases a low dose of a progestin and estrogen over three weeks. [13] The slow release of the hormones prevents pregnancy by blocking ovulation and causes changes in the cervical mucus that may stop implantation from occurring, as well. [14]

Dosing

The low dose is a constant rate that averages to about 0.015 mg of ethinyl estradiol and 0.12 mg etonogestrel per day. [15]

Administration

The contraceptive vaginal ring can be used at any time during the menstrual cycle as long as the patient is not currently pregnant. The standard process for administration is to insert the ring and leave it inside the vagina for 21 days, then remove it and have a break for 7 days without the ring inserted. After the 7 day break, a new ring should be reinserted for a 21 day period, and the cycle will continue thereafter. [16] However, some patients may choose to have a shorter ring-free break or no break at all, which has been shown to be just as safe and effective as the regimen with breaks. About 9% of individuals using a vaginal ring will still get pregnant every year, although this drops to 1% with perfect use. The most common mistakes when using the ring are adherence issues and incorrect administration, including forgetting to replace the ring on time and failure to insert the ring far enough into the vagina. [17] A study in Kenya demonstrated that there was concern circling on vaginal insertion and ring placement that called for practice from users, initially. Comparably, in Rwanda participants, there were challenges with ring insertion and removal originally but those worries dissipated with practice, and later described the process as "easy". [18] Multiple other common reasons for nonadherence include removing the ring for washing or before sexual intercourse. If the ring has been removed for more than three hours, then backup contraception should be used until the ring has been inserted and back in place for at least seven days. [19] Due to lack of patient education, some users struggle to insert the device comfortably and completely, which may hinder the contraceptive effects of the ring. [20] A large number of accidental expulsion of the vaginal ring occurs in the first few weeks of ring use, further suggesting inadequate or absence of counseling in use of contraceptive vaginal rings or inexperience in vaginal ring use. [21]

Annovera
Background
TypeHormonal Vaginal
First use2018
Effective rates (first year)
Perfect use97%
Typical use93%
Usage
Duration effect4 weeks
User remindersInsert & leave in for 3 weeks, remove for 1 week within menstrual cycle
Advantages and disadvantages
STI protectionNo
Safe while breastfeedingNo
WeightNo proven effect
BenefitsEasy insertion and removal

Side Effects

For any individual interested in using a contraceptive vaginal ring, it is important for their healthcare provider to provide counseling and support their understanding on these topics to ensure proper usage techniques and time. There is a small chance of blood clots, heart attacks and stroke with vaginal rings, and they are not recommended for individuals over 35 who smoke. [22] Studies find that 2.4% to 6.4% of contraceptive vaginal ring users experience uterine bleeding. [23]

A common concern with contraceptive vaginal rings are that they will impact vaginal health. [24] Multiple studies have demonstrated that vaginal health is not impacted as contraceptive vaginal rings do not affect the vaginal microbiome. [24] However, adverse effects that can lead to discontinuation of vaginal ring use include foreign body sensation, coital problems, and expulsion of the device. [19]

The one-year combined hormonal contraceptive ring is also known as Annovera. [7] It is a silicone elastomer vaginal ring containing the progestin segesterone acetate and the estrogen ethinylestradiol. [25]

Side effects are not common but may be present in some patients as a result of the hormones released by the ring. These side effects could include headaches, nausea, changes in period/menstrual cycle, sore breasts, or increased vaginal discharge. These symptoms are most common when the patient first begins using the ring and often subside within the first 2–3 months. While these are not necessarily reasons for concern, patients should always contact their primary care provider if they feel sick or faint, as it may be a sign for more serious adverse events in which case the vaginal ring usage should be discontinued. [26] [27]

Progesterone only vaginal ring

Indications

A progesterone vaginal ring (PVR) has also been developed. [2] It is specifically made for use during breastfeeding as it does not affect milk production. [2] The progesterone rings are highly effective for breastfeeding parents because exclusive breastfeeding itself, inducing lactational amenorrhea, [28] provides some protection from pregnancy, [29] and is considered safe for the new infants. [10]

Mechanism of action

The progesterone vaginal ring works by releasing a hormone, progesterone, over a three month period that leads to prevention of ovulation in the first postpartum year. [10] After the three months, the ring can be replaced with a new one if breastfeeding is continued or if prolonged contraception is desired. [29]

Dosing

Approximately 10 mg of progesterone diffuses from the ring per day through the vaginal walls into the bloodstream to suppress ovulation as well as thickening the cervical mucus to prevent sperm penetration into the uterus. [29]

Administration

Similar to the combined hormonal ring, the progesterone vaginal ring should be left in place and should not be removed for a period longer than two hours. [30] If it is removed for a longer period of time, backup contraception should be used until the ring has been inserted and back in place for at least seven days. [29]

The effectiveness rate is 98 to 99% in individuals using the progesterone vaginal ring for a year. [30]

Side Effects

Side effects include, but are not limited to, vaginal discharge, breast pain, and spotting or irregular bleeding. [30]

Advantages and disadvantages

Since the vaginal ring is a different form of birth control, there are certain advantages and disadvantages when compared to other forms.

Advantages

The ring offers better adherence from its longer duration effect as it needs to be changed at the very most once a month, compared to taking contraceptive pills daily. [31] Also, unlike the pill, it is not affected by gastrointestinal issues, such as vomiting and diarrhea, as the hormones are directly absorbed into the bloodstream. [32] [5] The estrogen dosing is lower compared to that of contraceptive pills and patches, which results in fewer side effects related to estrogen. [11] Additionally, there are a lower incidence rates of drug-drug interactions because the route does not involve the gastrointestinal tract, but rather the vaginal epithelium. [33] In a 2014 study conducted in Chilean individuals, a positive correlation between contraceptive counseling and preference for contraceptive vaginal rings has been demonstrated. [34] Preferences for an oral pill formulation, which was the most popular option, decreased after physician counseling; whereas, preferences for vaginal rings and transdermal patches increased after physician counseling. [34] When compared to other forms of contraception (combined oral contraceptives, contraceptive patch), the contraceptive vaginal ring showed similar, comparable efficacy and a better safety profile than its competitors. Oral contraceptive users experienced more adverse events of nausea and vomiting. However on the other hand, vaginal ring users experienced more vaginal discharge. The study found that adherence was far higher for contraceptive vaginal rings as they did not need to be changed daily like the other forms of contraception. This provides a good indication for real world effectiveness of vaginal rings as the primary source of contraception, as adherence issues are the main source of contraceptive failures. [35] An additional benefit is that the bleeding pattern of the contraceptive vaginal ring is consistent over a year long period, which has led to lower discontinuation rates. [36]

Disadvantages

Though it requires less maintenance, the vaginal ring will still have to be placed and removed at the right time. [11] A prescription is required to obtain a vaginal ring, which makes it less accessible compared to over the counter contraceptives. [5] The vaginal ring does not offer protection against all sexually transmitted infections. [11] The dapivirine vaginal ring (DPV-VR) is a relatively recent type of vaginal ring that reduces the risk of acquiring HIV during vaginal sex, with further research attempting to create a contraceptive and HIV preventative vaginal ring. [37] Unscheduled ring removals can increase the risk of failure, and further studies are needed to evaluate the efficacy of the ring beyond a 21-day period.

Contraindications

In addition, due to the higher risk of thromboembolism, the vaginal ring is not suitable for individuals with the following conditions: [5] [11]

Related Research Articles

<span class="mw-page-title-main">Combined oral contraceptive pill</span> Birth control method which is taken orally

The combined oral contraceptive pill (COCP), often referred to as the birth control pill, or simply as the pill, is a type of birth control that is designed to be taken orally by women. The pill contains two important hormones: a progestin and estrogen. When taken correctly, it alters the menstrual cycle to eliminate ovulation and 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 name Plan B One-Step 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 to 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.

<span class="mw-page-title-main">Ethinylestradiol</span> Estrogen medication

Ethinylestradiol (EE) is an estrogen medication which is used widely in birth control pills in combination with progestins. In the past, EE was widely used for various indications such as the treatment of menopausal symptoms, gynecological disorders, and certain hormone-sensitive cancers. It is usually taken by mouth but is also used as a patch and vaginal ring.

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.

<span class="mw-page-title-main">Desogestrel</span> Medication

Desogestrel is a progestin medication which is used in birth control pills for women. 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.

<span class="mw-page-title-main">Drospirenone</span> Medication drug

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.

<span class="mw-page-title-main">Norelgestromin</span> Pharmaceutical drug

Norelgestromin, or norelgestromine, sold under the brand names Evra and Ortho Evra among others, is a progestin medication which is used as a method of birth control for women. The medication is available in combination with an estrogen and is not available alone. It is used as a patch that is applied to the skin.

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

Norgestimate, sold under the brand names Ortho Tri-Cyclen and Previfem among others, is a progestin medication which is used in birth control pills for women and in menopausal hormone therapy. The medication is available in combination with an estrogen and is not available alone. It is taken by mouth.

<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, and 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.

Combined injectable contraceptives (CICs) are a form of hormonal birth control for women. They consist of monthly injections of combined formulations containing an estrogen and a progestin to prevent pregnancy.

<span class="mw-page-title-main">Medroxyprogesterone acetate</span> Injectible form of birth control

Medroxyprogesterone acetate (MPA), also known as depot medroxyprogesterone acetate (DMPA) in injectable form and sold under the brand name Depo-Provera among others, is a hormonal medication of the progestin type. It is used as a method of birth control and as a part of menopausal hormone therapy. It is also used to treat endometriosis, abnormal uterine bleeding, abnormal sexuality in males, and certain types of cancer. The medication is available both alone and in combination with an estrogen. It is taken by mouth, used under the tongue, or by injection into a muscle or fat.

<span class="mw-page-title-main">Segesterone acetate</span> Progestin medication

Segesterone acetate (SGA), sold under the brand names Nestorone, Elcometrine, and Annovera, is a progestin medication which is used in birth control and in the treatment of endometriosis in the United States, Brazil, and other South American countries. It is available both alone and in combination with an estrogen. 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.

<span class="mw-page-title-main">Estradiol/progesterone</span> Pharmaceutical combination

Estradiol/progesterone (E2/P4), sold under the brand names Bijuva and Juvenum, is a combined estrogen and progestogen medication which is used in the treatment of menopausal symptoms in postmenopausal women. It contains estradiol, an estrogen, and progesterone, a progestogen, and is available in both oral and intramuscular formulations. E2/P4 differs from other estrogen–progestogen formulations in that the sex-hormonal agents used are bioidentical.

<span class="mw-page-title-main">Estradiol (medication)</span> Steroidal hormone medication

Estradiol (E2) is a medication and naturally occurring steroid hormone. It is an estrogen and is used mainly in menopausal hormone therapy and to treat low sex hormone levels in women. It is also used in hormonal birth control for women, in hormone therapy for transgender women, and in the treatment of hormone-sensitive cancers like prostate cancer in men and breast cancer in women, among other uses. Estradiol can be taken by mouth, held and dissolved under the tongue, as a gel or patch that is applied to the skin, in through the vagina, by injection into muscle or fat, or through the use of an implant that is placed into fat, among other routes.

<span class="mw-page-title-main">Progesterone (medication)</span> Medication and naturally occurring steroid hormone

Progesterone (P4) is a medication and naturally occurring steroid hormone. It is a progestogen and is used in combination with estrogens mainly in hormone therapy for menopausal symptoms and low sex hormone levels in women. It is also used in women to support pregnancy and fertility and to treat gynecological disorders. Progesterone can be taken by mouth, in through the vagina, and by injection into muscle or fat, among other routes. A progesterone vaginal ring and progesterone intrauterine device used for birth control also exist in some areas of the world.

<span class="mw-page-title-main">Ethinylestradiol/etonogestrel</span> Pharmaceutical birth control combination

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.

<span class="mw-page-title-main">Combined hormonal contraception</span> Form of hormonal contraception combining both an estrogen and a progestogen

Combined hormonal contraception (CHC), or combined birth control, is a form of hormonal contraception which combines both an estrogen and a progestogen in varying formulations.

<span class="mw-page-title-main">Segesterone acetate/ethinylestradiol</span> Combination hormonal birth control

Segesterone acetate/ethinylestradiol (EE/SGA), sold under the brand name Annovera, is a contraceptive vaginal ring and combined form of hormonal birth control which contains segesterone acetate, a progestin and ethinylestradiol, an estrogen. It contains 17.4 mg ethinylestradiol and 103 mg segesterone acetate, releases an average of 13 μg ethinylestradiol and 0.15 mg segesterone acetate per day.

References

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  37. ↑ "WHO recommends the dapivirine vaginal ring as a new choice for HIV prevention for women at substantial risk of HIV infection". www.who.int. Archived from the original on 2022-08-03. Retrieved 2022-08-01.
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