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Patient education: Hormonal methods of birth control (Beyond the Basics)

Patient education: Hormonal methods of birth control (Beyond the Basics)
Literature review current through: Jan 2024.
This topic last updated: Dec 11, 2023.

INTRODUCTION — There are a number of methods available to help prevent pregnancy. Deciding which method is right for you involves considering a number of issues, including convenience, cost, potential side effects, and your future pregnancy plans. (See "Patient education: Birth control; which method is right for me? (Beyond the Basics)".)

Hormonal methods of birth control (contraception) contain either estrogen plus progestin or progestin only; they are a safe and reliable way to prevent pregnancy for most people. Hormonal methods include an implant, an intrauterine device (IUD), injections, pills, vaginal rings, and skin patches.

This document discusses the various hormonal methods of birth control that are available. Nonhormonal methods, which include the copper IUD, barrier methods (such as condoms), and the cervical cap, diaphragm, and sponge, are discussed separately. (See "Patient education: Long-acting methods of birth control (Beyond the Basics)", section on 'Intrauterine device' and "Patient education: Barrier and pericoital methods of birth control (Beyond the Basics)".)

CHOOSING A BIRTH CONTROL METHOD — It can be difficult to decide which birth control method is best due to the variety of options available. The best method is one that will be used consistently and does not cause bothersome side effects. Other factors to consider include:

Efficacy (how well it works to prevent pregnancy)

Convenience

How long the drug or device can be used

Whether and how it affects your monthly period

Type and frequency of side effects

Affordability

Privacy concerns

Whether or not it also protects against sexually transmitted diseases

How quickly your fertility will return if you stop taking it

You should also think about whether you are comfortable remembering to take a pill every day, whether you want to involve your partner(s) in the decision, and whether and when you might want to get pregnant in the future. No birth control is perfect; you must balance the advantages and disadvantages of the different options and decide which method is best for you.

BIRTH CONTROL IMPLANT — The implant (brand name: Nexplanon) is a small rod that contains the hormone progestin. It is inserted under the skin into the upper inner arm by a health care provider (figure 1). It is effective for at least three years but can be removed earlier if you decide you want to get pregnant or simply prefer not to continue use of the implant. Insertion and removal can be done in an office or clinic.

The implant is one of the most effective methods of birth control. It provides at least three years of protection from pregnancy as progestin is slowly released into the surrounding tissues. Depending on when during the menstrual cycle the implant is placed, backup birth control (for instance condoms) may be recommended for one week following placement. Irregular bleeding is the most bothersome side effect. Fertility returns rapidly after the rod is removed.

Side effects — The most common side effects of the implant are irregular/unpredictable bleeding.

IUD WITH PROGESTIN — There are several intrauterine devices (IUDs) that release a hormone called levonorgestrel (a type of progestin). Two types of levonorgestrel IUDs (brand names: Mirena, Liletta) can be left in place for up to eight years. The other options (brand names: Kyleena, Skyla) are somewhat smaller and can be left in place for up to five years (Kyleena) or three years (Skyla). All of the levonorgestrel IUDs are highly effective in preventing pregnancy.

Side effects — Although irregular bleeding is common initially after progestin IUD placement, bleeding tends to diminish over time. With ongoing use, people using Mirena or Liletta often experience little or no bleeding. Those who use Kyleena or Skyla are more likely to continue having monthly periods.

A complete discussion of the implant and IUDs is available separately. (See "Patient education: Long-acting methods of birth control (Beyond the Basics)".)

INJECTABLE BIRTH CONTROL — The only injectable contraceptive currently available in the United States is depot medroxyprogesterone acetate or DMPA (brand name: Depo-Provera). DMPA is injected deep into a muscle, such as in the buttock or upper arm, or injected subcutaneously (under the skin). With either type of injection, this contraceptive is given once every three months.

DMPA prevents ovulation and thickens the cervical mucus, making the cervix impenetrable to sperm. If you get your first dose of DMPA during the first seven days of your menstrual period, it prevents pregnancy immediately. If you get your first dose after the seventh day of your period, you should use a second form of birth control (eg, condoms) for seven days. DMPA is very effective, with a failure (pregnancy) rate of less than 1 percent when repeat injections are given on time.

Side effects — The most common side effects of DMPA are irregular or prolonged bleeding and spotting, particularly during the first few months of use. Up to 50 percent of people completely stop having menstrual periods (doctors call this "amenorrhea") after one year of DMPA use. Monthly periods generally return within six months of the last DMPA injection, although, in some cases, it may take longer for periods to return. Some people gain weight while they are getting DMPA injections.

In people who get the DMPA shot, there is no increased risk of cardiovascular complications or cancer. Use of DMPA is associated with decreased bone mineral density; however, this effect is mostly or completely reversed after stopping the injections. Studies have not shown an increased risk of bone fractures in people who have used DMPA in the past.

Because DMPA is long-acting, it should not be used if you want to get pregnant shortly after stopping the medication. Although most people are able to conceive within 10 months, fertility may not return for up to 18 months after the last injection.

Benefits compared with birth control pills — There are a number of people who prefer DMPA to the pill, including those who:

Have difficulty remembering to take a pill every day

Value the privacy with DMPA use

Cannot use estrogen

Also take seizure medications, which can be less effective with combination hormonal contraceptives (see 'Anticonvulsants' below)

Additional benefits of DMPA include a decreased risk of uterine cancer and pelvic inflammatory disease.

BIRTH CONTROL PILLS — Most oral contraceptives, commonly called "the pill," contain a combination of estrogen and progestin. The combination pill reduces the risk of pregnancy by:

Preventing ovulation

Keeping the mucus in the cervix thick and impenetrable to sperm

Keeping the lining of the uterus thin

The pill makes bleeding more regular, with fewer days of flow and overall lighter flow. Other benefits of the pill include a reduction in:

Menstrual cramps or pain

Risk of ovarian cancer or cancer of the endometrium (uterine lining)

Acne

Iron-deficiency anemia (a low blood count due to low iron levels)

One potential downside of the pill is that, in order to maximize efficacy, you have to remember to take it every day, ideally at the same time of day (see 'Efficacy' below). Some people find this difficult or inconvenient.

Efficacy — When taken properly, birth control pills are an effective form of contraception; however, skipping pills or forgetting to restart the pill after the week of your period will increase risk of pregnancy (see 'When to expect bleeding' below). Approximately 9 out of every 100 people who take birth control pills for one year will have an unintended pregnancy.

Missed pills are a common cause of pregnancy. In general, if you forget to take an active pill (containing hormones), you should take it as soon as possible and take the next one at the usual time it is due. If you miss more than two pills, use a backup method of birth control (eg, condoms) for seven days.

Side effects — Possible side effects of the pill include:

Nausea, breast tenderness, bloating, and mood changes – These typically improve within two to three months without treatment (while continuing the pill).

Irregular bleeding – Irregular bleeding, also called "breakthrough bleeding" or "spotting," is particularly common during the first few months of taking the pill. It almost always resolves without any treatment within two to three months. Forgetting a pill can also cause breakthrough bleeding.

Taking birth control pills does not cause weight gain.

Potential complications — When the pill was first introduced in the 1960s, the doses of both hormones (estrogen and progestin) were quite high. Because of this, cardiovascular complications occurred, such as high blood pressure, heart attacks, strokes, and blood clots in the legs and lungs.

The pills prescribed today have much lower doses of progestin and estrogen, which has decreased the risk of these complications. As a result, birth control pills are now considered a reliable and safe option for most healthy, nonsmoking people. While today's lower-dose pills do elevate the risk of blood clots, this risk is actually lower than the risk during pregnancy or soon after giving birth.

Experts have studied the possible association between taking the pill and the risk of breast cancer. While these studies have had mixed results, there is some evidence that people who take the pill do have a slightly higher risk of getting breast cancer later in life than those who do not. However, if there is an increase in risk, it is very small, especially in younger people. It is important to balance this against the benefits of the pill, which include not only pregnancy prevention but a sizable reduction in the risk of ovarian and endometrial (uterine) cancer. (See 'Birth control pills' above.)

Who should not take the pill? — Because of an increased risk of complications, you should not take the pill if you:

Are 35 or older and smoke cigarettes (as this puts you at high risk for cardiovascular complications such as blood clots or heart attack).

Could be pregnant.

Have had blood clots or a stroke in the past (as this increases your risk of blood clots while taking the pill).

Have a history of an "estrogen-dependent" tumor (eg, breast or uterine cancer).

Have abnormal or unexplained menstrual bleeding (in which case the cause of the bleeding should be investigated before starting the pill).

Have active liver disease (the pill could worsen the liver disease).

Have migraine headaches associated with certain visual or other neurologic symptoms (eg, aura), which increases your risk of stroke.

If you are taking the pill, tell your health care provider right away if you experience abdominal pain, chest pain, severe headaches, eye problems, or severe leg pain. These could be symptoms of several serious conditions including heart attack, blood clot, stroke, and liver or gallbladder disease.

Some people may take the pill under certain circumstances but need close monitoring. Talk with your doctor or nurse if you:

Have high blood pressure – You may experience a further increase in blood pressure and should be monitored more frequently while on the pill.

Take certain medication for seizures (epilepsy) – In this case, the pill may be slightly less effective in preventing pregnancy because the seizure medicines change the way it is metabolized. (See 'Anticonvulsants' below.)

Have diabetes mellitus – People with diabetes and kidney disease or vascular complications from diabetes should not use the pill.

Medication interactions — The pill may not work as well to prevent pregnancy if you also take certain other medications.

Anticonvulsants — Some anticonvulsants, including phenytoin (sample brand names: Dilantin, Phenytek), carbamazepine (sample brand names: Carbatrol, Tegretol), barbiturates, primidone (brand name: Mysoline), topiramate (sample brand name: Topamax), and oxcarbazepine (sample brand name: Trileptal), decrease the effectiveness of birth control pills as well as patches, vaginal rings, and the implant. As a result, people who take these anticonvulsants are advised to avoid hormonal birth control methods (with the exception of depot medroxyprogesterone acetate or DMPA [brand name: Depo-Provera] and intrauterine devices [IUDs] with progestin). (See 'Injectable birth control' above and 'IUD with progestin' above.)

Other anticonvulsants do not appear to reduce contraceptive efficacy, including gabapentin (sample brand names: Gralise, Neurontin), lamotrigine (sample brand names: Lamictal, Subvenite), levetiracetam (sample brand names: Keppra, Roweepra), tiagabine (brand name: Gabitril), and valproic acid (brand name: Depakote). However, there is some concern that oral contraceptives may reduce the effectiveness of lamotrigine, potentially increasing the risk of seizures.

If you take any anti-seizure medications, it is important to talk with your health care provider about possible interactions before starting the pill or another hormonal birth control method.

Antibiotics — Rifampin, which is sometimes used to treat tuberculosis, can decrease the efficacy of hormonal birth control. As a result, people who take rifampin are advised to avoid most hormonal birth control methods, with the exception of DMPA (brand name: Depo-Provera) and IUDs with progestin (see 'Injectable birth control' above and 'IUD with progestin' above). Alternative options include a copper IUD, condoms, or a diaphragm, or tubal ligation (permanent birth control). (See "Patient education: Long-acting methods of birth control (Beyond the Basics)" and "Patient education: Barrier and pericoital methods of birth control (Beyond the Basics)" and "Patient education: Permanent birth control for women (Beyond the Basics)".)

Contrary to popular belief, other (more commonly used) antibiotics do not affect the efficacy of hormonal birth control methods. Backup contraception is not needed when you take these antibiotics.

St. John's Wort — St. John's wort, an herbal supplement sometimes taken to treat depression, may reduce the effectiveness of birth control pills, and possibly the patch and ring. (See "Patient education: Depression treatment options for adults (Beyond the Basics)".)

Starting the pill — Ideally, you should start taking the pill on the first day of your period. This provides protection from pregnancy beginning immediately.

As long as you are sure you are not pregnant (which can be confirmed with a urine pregnancy test), it is also an option to start the pill as soon as your doctor prescribes it, regardless of where you are in your menstrual cycle. This is called the "quick start" method. If you do this, you will need to use a backup form of birth control (eg, condoms) for the first seven days after the quick start.

Many people start taking the pill on the first Sunday after their period starts (because most pill packs are arranged for a Sunday start). If you do this, you will also need to use some form of backup contraception (eg, condoms) for the first seven days after the Sunday start.

When to expect bleeding — Traditionally, the pill is taken on a 28-day cycle that includes 21 days of hormone pills followed by 7 days of placebo pills ("no hormone pills") that do not contain hormones. Newer formulations have a longer duration of hormone pills (eg, 24 days) and fewer days of placebo pills (eg, 4 days). It is not necessary to take the placebo pills as they do not contain any active ingredients, but many people find it easier to stay on schedule when they continue to take a daily pill throughout the entire 28-day cycle.

Bleeding should occur during the fourth week of the pill pack (ie, the week that you are taking placebo pills or no pills). However, some people have irregular breakthrough bleeding or spotting in the first few months. (See 'Side effects' above.)

Continuous dosing — Some people prefer to take hormone-containing birth control pills continuously, without the week of no pills or placebo pills. This allows you to control whether and when you have monthly bleeding. This regimen may be a good option if you have painful periods, endometriosis (a condition that causes pelvic pain), or bothersome premenstrual symptoms, including mood changes.

Traditional birth control pill packs can be dosed continuously to get rid of monthly bleeding. To do this, you take the first three weeks of a pill pack, then immediately start a new pack the next day (without taking a break or taking the placebo pills). This can be continued for as long as desired. A pill called Seasonale was specifically designed for continuous dosing. You take an active pill every day for 12 weeks, followed by seven days of placebo pills. With this regimen, you only experience bleeding once every three months. Seasonique is similar; it contains 84 days of active pills and 7 days of low-dose estrogen pills. The addition of low-dose estrogen pills is intended to reduce breakthrough bleeding and possibly other symptoms, such as mood changes and headaches. Both are available as generic medications that work in the same way.

Over time, using continuous-dosing regimens results in fewer bleeding episodes per year (or no bleeding at all); however, many people experience unpredictable breakthrough bleeding when starting a continuous-dosing regimen. Breakthrough bleeding is inconvenient but does not mean that the pills are less effective (assuming you are taking them at the same time each day and not skipping any active pills).

Progestin-only pills — Some pills contain only progestin (sometimes called the "mini pill"); these may be an option for people who cannot or should not take estrogen. This includes those who are breastfeeding or who have worsened migraines or high blood pressure with combination contraceptive pills. Progestin-only pills appear to be as effective as combination pills when taken at the same time every day, but they have a slightly higher failure rate if you are more than three hours late in taking them. A backup method of birth control should be used for seven days if you forget a pill or are more than three hours late in taking it. Breakthrough bleeding or spotting is common with both types of progestin-only pills.

Progestin-only pills are available in 28-day packs. Two types of progestin-only pills are available in the United States. For one type (containing norethindrone), all 28 pills contain the hormone (ie, there is no "placebo week"). For the second type (containing drospirenone), each pack includes 24 hormone pills and 4 placebo pills. The drospirenone pill may be more effective than the norethindrone pill. A disadvantage of the drospirenone pill is that no generic is available, which may make it more expensive.

VAGINAL RINGS — These are flexible plastic rings (figure 2) that contain estrogen and a progestin. The ring is inserted into the vagina, and the hormones are slowly absorbed into the body. This prevents pregnancy, similar to the pill. You keep the ring in your vagina for three weeks then leave it out for one week, during which you will experience bleeding. The following week, you insert a new ring or reinsert the previous one (one type of ring is reusable for approximately one year, while the other type needs to be discarded and replaced each month). As long as the ring remains in the vagina and is not uncomfortable, the ring's position inside the vagina is not important.

You can start using the vaginal ring anytime during your menstrual cycle. If you start it more than seven days after the first day of your last period, or if you are not sure when your last period started, you should use a backup method of contraception (eg, condoms) for the first seven days after inserting the ring.

Most people cannot feel the ring while it is in place, and in most cases, it is easy to insert and remove. It may be removed for a short time if desired, as discussed below, but should be left in during intercourse. Your partner most likely will not be able to feel the ring. You should use your fingers to check before and after sex to confirm the ring is in place. If the ring is left out for more than a few hours, you may be able to put it back in, or you may need to discard it, depending on which type of ring you use and where you are in your menstrual cycle. Because the instructions can vary, it is important to read the information that comes with your ring.

If you use the ring that gets replaced each month (sample brand names: NuvaRing, EluRyng):

During the first two weeks of your cycle, you can reinsert the ring and continue with the usual schedule. The ring should be rinsed in cool or warm (but not hot) water, without soap or detergent, before it is reinserted.

During the third week, you can insert a new ring and begin a new cycle immediately, in which case you will not get a period. If the ring was previously in place for at least seven days in a row, you can also choose to leave the ring out for up to one week (during which you have your period) and then insert a new one.

Regardless of where you are in your cycle, if the ring is left out for more than three hours, you should use a backup method of birth control (eg, condoms) for the next seven days. Any backup method other than the female condom or diaphragm can be used.

If you use the reusable ring that gets reinserted each month (brand name: Annovera), the instructions are the same regardless of where you are in your menstrual cycle:

If the ring is out for two hours or less, you can reinsert it. Before doing so, wash the ring with mild soap, rinse with water, and gently dry.

If the ring is out for more than two hours, either continuously or cumulatively (eg, if you take it out two separate times that add up to more than two hours), you should also clean and insert the ring. However, you also must use a backup form of birth control (eg, condoms) for the next seven days.

As with the pill, in addition to being an effective method of preventing pregnancy, the vaginal ring also has other potential benefits. These include a reduction in menstrual cramps, iron-deficiency anemia, and the risk of certain cancers. (See 'Birth control pills' above.)

Risks and side effects are also similar to those of oral contraceptives. (See 'Side effects' above and 'Potential complications' above.)

BIRTH CONTROL SKIN PATCHES — Birth control skin patches (sample brand names: Xulane, Twirla) contain estrogen and progestin, similar to oral contraceptives. Both patches are similar to the pill in terms of efficacy in preventing pregnancy. Some people prefer patches because they do not require remembering to take a pill each day; on the other hand, some people do not like having a visible patch on their skin. Neither patch type should be used by people with a body mass index (BMI) of 30 kg/m2 or higher.

The patch is worn for one week on the shoulder, upper back, abdomen, or buttock (figure 3); one type (brand name: Twirla) can also be worn on the upper arm. After one week, you remove the old patch and apply a new one; this is done for three weeks. During the fourth week, you do not apply a new patch; you will experience bleeding during this time.

The patch is ideally started on the first day of your period. This approach provides protection from pregnancy immediately. If you prefer, you can also start using the patch on the day it is prescribed, regardless of where you are in your menstrual cycle (called "quick start"). If you do this, you will need to use a backup form of birth control (eg, condoms) for the first seven days.

As with the pill, in addition to being an effective method of preventing pregnancy, the patch also likely has other potential benefits, although studies are limited. These include a reduction in menstrual cramps, iron-deficiency anemia, and the risk of certain cancers. (See 'Birth control pills' above.)

While efficacy is similar to the pill, the Xulane patch may deliver a higher overall dose of estrogen. Some studies found that this was associated with an approximate doubling of the risk of blood clots compared with use of oral contraceptives (the pill). However, other studies found no increase in risk compared with people using the pill. Further study is needed to define this risk.

PREGNANCY AFTER HORMONAL BIRTH CONTROL — The length of time it takes to become pregnant after use of a hormonal method of birth control depends upon which method was used, as well as some individual factors.

Most people return to their normal level of fertility within a cycle or two. For some, it may take several months before their cycle (including when they ovulate) becomes regular and they can get pregnant. This is more likely for people whose periods were irregular before starting birth control. However, hormonal birth control does not increase the risk of infertility. In general:

People who use the pill, skin patch, or vaginal ring usually start ovulating regularly again within one to three months of stopping birth control.

With injectable depot medroxyprogesterone acetate (DMPA; brand name: Depo-Provera), return of fertility can be delayed. Approximately half of people who want to be pregnant are pregnant within 10 months of stopping DMPA. However, some people will not get their periods back for up to 18 months. (See 'Injectable birth control' above.)

People who get an implant (eg, Nexplanon) or an intrauterine device (IUD) usually begin to ovulate again within one month after the device is removed.

EMERGENCY CONTRACEPTION — If you have unprotected sex or a problem with your birth control (for example, you miss a pill, your skin patch falls off, or your vaginal ring falls out), you can use emergency contraception to reduce your risk of pregnancy. Forms of emergency contraception include the copper intrauterine device (IUD), levonorgestrel 52 mg IUDs (commercial names Mirena and Liletta), and pills. Emergency contraception should be taken as soon as possible after sex, ideally within 120 hours (five days). More information about this is available separately. (See "Patient education: Emergency contraception (Beyond the Basics)".)

WHERE TO GET MORE INFORMATION — Your health care provider is the best source of information for questions and concerns related to your medical problem.

This article will be updated as needed on our web site (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for health care professionals, are also available. Some of the most relevant are listed below.

Patient level information — UpToDate offers two types of patient education materials.

The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.

Patient education: Hormonal birth control (The Basics)
Patient education: Choosing birth control (The Basics)
Patient education: Barrier methods of birth control (The Basics)
Patient education: Endometriosis (The Basics)
Patient education: Ovarian cysts (The Basics)
Patient education: Premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD) (The Basics)

Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.

Patient education: Long-acting methods of birth control (Beyond the Basics)
Patient education: Barrier and pericoital methods of birth control (Beyond the Basics)
Patient education: Birth control; which method is right for me? (Beyond the Basics)
Patient education: Depression treatment options for adults (Beyond the Basics)
Patient education: Emergency contraception (Beyond the Basics)

Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.

Intrauterine contraception: Candidates and device selection
Contraception: Issues specific to adolescents
Depot medroxyprogesterone acetate (DMPA): Formulations, patient selection and drug administration
Emergency contraception
Internal (formerly female) condoms
Fertility awareness-based methods of pregnancy prevention
Hormonal contraception for menstrual suppression
Pericoital (on demand) contraception: Diaphragm, cervical cap, spermicides, and sponge
External (formerly male) condoms
Contraception: Counseling and selection
Combined estrogen-progestin oral contraceptives: Patient selection, counseling, and use
Contraception: Progestin-only pills (POPs)
Combined estrogen-progestin contraception: Side effects and health concerns

The following organizations also provide reliable health information.

National Library of Medicine

(https://medlineplus.gov/healthtopics.html)

National Institute of Child Health and Human Development (NICHD)

Toll-free (800) 370-2943

www.nichd.nih.gov/

National Women's Health Resource Center (NWHRC)

Toll-free: (877) 986-9472

www.healthywomen.org/

Planned Parenthood Federation of America

Phone: (212) 541-7800

https://www.plannedparenthood.org/

Bedsider

(www.bedsider.org)

The Hormone Foundation

(www.hormone.org/)

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Disclaimer: This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider's examination and assessment of a patient's specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms. 2024© UpToDate, Inc. and its affiliates and/or licensors. All rights reserved.
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