Birth Control In-Depth Report
Contraceptives are devices, drugs, or methods for preventing pregnancy, either by preventing the fertilization of the female egg by the male sperm or by preventing implantation of the fertilized egg. Background
Contraceptive OptionsChoosing the appropriate contraceptive is a personal decision. Contraceptive options include:
- Hormonal contraceptives (oral contraceptives, skin patch, vaginal ring, implant, injection)
- Intrauterine devices (IUDs), which contain either a hormone or copper
- Barrier devices with or without spermicides (diaphragm, cervical cap, sponge, condom)
- Fertility awareness methods (temperature, cervical mucus, calendar, symptothermal)
- Female sterilization (tubal ligation, Essure)
Determining EffectivenessContraceptive effectiveness is characterized by "typical use" and "perfect use":
- Typical use refers to real-life conditions, in which mistakes (such as forgetting to take a birth control pill at the right time) sometimes happen.
- Perfect use refers to contraceptives that are used correctly each time intercourse occurs.
Oral contraceptives (birth control pills) are available only by prescription and come in either a combination of estrogen and progestin or progestin alone. Many brands of each form are available. Although both are equally effective with typical use, the combined pill is more effective with perfect use, and most women choose this form. Oral Contraception and Combination Hormonal Methods
Some women, however, experience severe headaches or high blood pressure from the estrogen in the combined pill and must take the progestin-only pill. Not all combined pills or progestin-only pills are alike, and brands differ in the amount of estrogen or progestin they contain. Many oral contraceptive combined brands now use lower estrogen doses and have fewer side effects than earlier oral contraceptives.
For all oral contraceptive users, a check-up at least once a year is essential. It is also important for women to have their blood pressure checked 3 months after beginning the pill. Once woman stop taking oral contraceptives they usually regain fertility within 3 - 6 months, but some women may regain it even sooner.
Hormones Used in ContraceptivesEstrogen (Estradiol)
Estrogen is the major female hormone and is responsible for female characteristics. The estrogen compound used in most oral contraceptives is estradiol , which is always used with a progestin.
Effects on Reproduction. When used throughout a menstrual cycle with progesterone, estrogen suppresses the actions of other reproductive hormones (luteinizing hormone, or LH, and follicle stimulating hormone, or FSH) and prevents ovulation.
When used in contraception, progesterone is referred to by one of several names:
- Progesterone is the name for the natural hormone.
- Progestogen is a synthetic form.
- Progestin is the term for any hormone, natural or synthetic, that causes progesterone effects; it is used as the general term in this report.
Progesterone can prevent pregnancy by itself in several ways:
- Blocking luteinizing hormone (LH) and preventing ovulation
- Maintaining a powerful barrier against the entry of sperm into the uterus by keeping the cervical mucus thick and sticky
- Second generation (levonorgestrel, norethisterone).
- Third generation (desogestrel, gestodene, norgestimate, drospirenone). The third-generation progestins tend to have fewer side effects. Some studies suggest, however, they may pose a slightly higher risk for blood clots than the older progestins.
Combination Estrogen-Progestin Contraceptive PillsOral contraceptives that contain both estrogen and progestin are the more common type of oral contraceptive. At least 10 million American women and 100 million women worldwide use combination oral contraceptives. When they were first marketed in the early 1960s, oral contraceptives contained as much as 5 times the amount of estrogen and up to 10 times the amount of progestin currently used. After reports of severe complications (stroke, heart attack, and pulmonary embolisms) in young women, the hormone amounts were significantly reduced.
The estrogen compound used in most oral contraceptives is ethinyl estradiol (also called estradiol, or EE). Fifty micrograms of estradiol is considered high dose, 30 - 35 micrograms are considered average dose, and 20 micrograms or fewer is low-dose. (The high doses found in current oral contraceptives are still much lower than earlier forms of the pill.) Doctors recommend using the lowest possible progestin and estrogen doses. Estrogen doses should not exceed 50 micrograms, as higher doses increase the risk for complications.
Many different types of progestins are used in combination with estradiol. Some common types of progestin, and popular combination oral contraceptive brands, include:
- Desogestrel is the progestrin used in Mircette. Approved in 1998, Mircette was the first oral contraceptive to offer a low estrogen dose and a new type of dosing regimen. Some studies suggest an increased risk for blood clots with desogesterel.
- Drospirenone is used in Yasmin and Yaz. (Yaz contains a lower dose of estrogen than Yasmin.) Because drospirenone increases blood levels of potassium, women should not use Yasmin or Yaz if they have kidney, liver, or adrenal diseases.
- Levonorgestrel is used in Seasonale and Seasonique, as well as many other oral and non-oral contraceptives.
- Norethindrone is used in Loestrin and Loestrin 24 Fe (which adds iron supplements to the placebo pills).
- Norgestrel is used in various generic and brand contraceptives.
- Each pill in a 21-day pack contains estrogen and progestin. Women take 1 pill a day for 21 days, and then wait 7 days before starting a new 21-day pack.
- 28-day packs typically start with 21 hormone pills and add 7 placebo pills that do not contain hormones. After taking hormone pills for 21 days, a woman takes the inactive pills for 7 days. Some newer brands, like Yaz, use 24 days of active pills and 4 days of inactive pills. Mircette uses 21 days of low-dose progestin and estrogen, followed by 2 placebo days, and then 5 days of very low-dose estrogen. Loestrin 24 Fe uses 24 days of active pills followed by 4 days of iron-containing placebo pills.
Taking the Pills. A woman usually takes the first pill either on the Sunday after her period starts or during the first 24 hours of her period. (The first pill can be started at any time during the menstrual cycle without affecting the bleeding patterns. Ovulation can occur that month, however.) The remaining pills are taken once a day, ideally at the same time of day, until the pack is used up. If a woman has a 21-day pack, she waits 7 days before starting a new pack. If she is on the 28-day pack, she takes the 7 inactive pills. Women should use another method of birth control during the first month taking the pill.
If you skip one or more pills, take the following precautions:
- Missing the first pill in a new cycle. Take a tablet as soon as you remember and the next one at the usual time. Two tablets can be taken in one day. Use barrier contraception for 7 days after the missed dose.
- Missing a pill 2 days in a row. Take 2 pills as soon as you remember and then 2 more the following day. Also use back-up barrier contraception until the next pill cycle.
- Missing more than 2 days. Discard the pack, use a back-up birth control method, and begin a new cycle on the following Sunday, even if you have started bleeding.
Continuous-Dosing Oral ContraceptivesStandard oral contraceptives come in a 28-pill pack that contains 21 active pills and 7 inactive pills. Newer "continuous-dosing" (also called "continuous-use") oral contraceptives aim to reduce -- or even eliminate -- monthly periods and thereby prevent the pain and discomfort that may still accompany menstruation in women taking oral contraceptives. Women who have medical conditions, (such as endometriosis), which cause heavy or painful menstrual periods may benefit from continuous-dosing oral contraceptives. These oral contraceptives contain a combination of estradiol and the progesterone levonorgestrel, but use extending dosing of active pills.
Seasonale, the first continuous-dosing contraceptive, contains 81 days of active pills followed by 7 days of inactive pills. Women who take Seasonale have on average a period every 3 months. Seasonique, a follow-up to Seasonale, also produces about 4 periods a year. With Seasonique, a woman takes 84 days of levonorgestrol-estradiol pills followed by 7 days of pills that contain only low-dose estradiol.
Lybrel supplies a daily low dose of levonorgestrol and estradiol with no inactive pills. Because Lybrel contains only active pills, which are taken 365 days a year, it completely eliminates monthly menstrual periods. About 60% of women who take Lybrel completely stop menstrual periods by the end of the first year. Some women, however, experience occasional unscheduled bleeding or spotting during the first 3 - 6 months.
Progestin-Only Oral Contraceptives ("Mini-Pills")Progestin-only pill brands include:
- Levonorgestrel (Plan B)
- Norethindrone (Micronor, Aygestin, Nor-QD)
- Norgestrel (Ovrette)
Progestin-only pill users experience even lighter periods than those taking combination pills. Some may not have periods at all. Because these pills do not contain estrogen, they may be a safer choice for women over age 35, smokers, and those who have other risk factors that contraindicate estrogen use.
Advantages of Oral ContraceptivesOral contraceptives are the choice of most American women who use birth control, making them the most popular reversible contraceptives in the U.S. Oral contraceptives are among the most effective contraceptives. Failure rates are relatively low (9% with typical use) and are usually due to noncompliance.
Oral contraceptives also have the following advantages, which may vary depending on the type and brand used:
- Reduce menorrhagia (heavy menstrual bleeding) and, therefore, reduce the risk of anemia.
- Reduce dysmenorrhea (severe menstrual pain)
- May help reduce symptoms of premenstrual syndrome. Yaz is specifically approved for treating premenstrual dysphoric disorder (premenstrual depression).
- Improve acne
- Improve symptoms of endometriosis.
- Reduce risks of ovarian cysts
- Possible protection against bone loss with estrogen-containing oral contraceptives
- Reduce risks of ovarian and endometrial (uterine) cancers with long-term use (more than 3 years)
Disadvantages of Oral ContraceptivesCommon Side Effects. Many women experience some side effects during the first 2 - 3 months of birth control use. These side effects usually subside. Estrogen and progesterone have different side effects, and women on the combined pill may experience different effects from those on the progestin-only pill.
Common side effects of oral contraceptives include:
- Nausea and vomiting (can often be controlled by taking the pill during a meal or at bedtime)
- Headaches (in women with a history of migraines, they may worsen)
- Breast tenderness and enlargement
- Irregular bleeding or bleeding between periods
- Weight gain
Serious Side Effects . Symptoms of serious problems may include severe abdominal pain, chest pain, unusual headaches, visual disturbances, or severe pain or swelling in the legs. If you experience any of these symptoms, you should immediately contact your doctor.
Potential Risks . Combination birth control pills can increase the risk of developing or worsening certain serious medical conditions. The risks depend in part on a woman’s medical history. You should discuss your health history with your doctor to determine if combination oral contraceptives are safe for you. This is especially important for women who are age 35 or older, smoke, or have a history of high blood pressure, high cholesterol or unhealthy blood lipid profile, diabetes, or migraine headaches.
Serious risks of birth control pills may include:
- Heart and Circulation Problems. Combination birth control pills contain estrogen, which can increase the risk for stroke, heart attack, and blood clots in some women. The risk is highest for women who smoke or have a history of heart disease risk factors (such as high blood pressure or unhealthy cholesterol/lipid levels) or cardiac events. Women who have certain metabolic disorders, such as polycystic ovary syndrome (PCOS), are also at higher risk for heart-related complications associated with these pills. Women who have migraines may possibly be at increased risk for stroke and may need to consider progestin-only pills or other contraceptive methods in place of combination oral contraceptives.
- Venous Thromboembolism. All combination estrogen/progestin birth control products carry an increased risk for blood clots in the veins (venous thromboembolism), which can lead to blood clots in the arteries of the leg or lung (pulmonary embolism). The risk is lower for oral contraceptives than for the birth control patch (Ortho Evra) or the ring (NuvaRing), which expose women to higher levels of estrogen than birth control pills. Women who smoke, who are obese, or who have heart disease risk factors may want to consider using alternatives to estrogen-containing contraceptives, such as progestin-only oral contraceptives ("mini-pills"), intrauterine devices, or barrier contraceptive methods.
- Diabetes. Women who have diabetes, and high blood pressure, vascular disease, kidney disease, or other diabetes-related health problems, should not take birth control pills.
- Cancer Risks. Several studies have reported a strong association between increased risk of cervical cancer and long-term use of oral contraception. Women who take oral contraceptives for more than 10 years appear to have a much higher risk of human papilloma virus (HPV) infection than those who do not use oral contraceptives. Women taking oral contraceptives for less than 5 years have no significantly higher risk. Although studies have been conflicting about whether estrogen in oral contraception increases the chances for breast cancer, the most recent research indicates that oral contraceptive use does not significantly increase breast cancer risk. Women who have used oral contraceptives may have slightly more risk for breast cancer than women who have never used them, but this risk declines once a woman stops using birth control pills. Long-term use of birth control pills reduces the risk for ovarian and uterine cancers.
- Liver Problems. In rare cases, oral contraceptives have been associated with liver tumors, gallstones, or jaundice. Women with a history of liver disease, such as hepatitis, should consider other contraceptive options.
- Interactions with Other Medications. Certain types of medications can interact with and decrease the effectiveness of oral contraceptives. These medications include anticonvulsants, antibiotics, antifungals, and antiretrovirals. The herbal remedy St. John’s wort can also interfere with birth control pills’ effectiveness. Make sure your doctor is aware of any drugs, vitamins, or herbal supplements that you take.
Other Methods for Administering Combination Hormones (Patch and Ring)New methods of administering the combination of progestin and estrogen are now available. Failure rates with perfect use (0.1 - 0.6%) are similar to those of combined oral contraceptives.
Skin Patch. Ortho Evra is a birth control skin patch. It contains a progestin (norelgestromin) and estrogen. The patch is placed on the lower abdomen, buttocks, or upper body (but not on the breasts). Each patch is worn continuously for a week and reapplied on the same day of each week. After three weekly patches, the fourth week is patch-free, which allows menstruation. (The patch remains effective for 9 days, so being slightly late in changing it should not increase the risk for pregnancy.)
The Ortho patch exposes women to higher levels of estrogen than most birth control pills, and therefore increases the risk for blood clots in the veins (venous thromboembolism). Venous thromboembolism can cause blockage in lung arteries and other serious side effects. Older women (over age 40) and women with risk factors for blood clots (such as cigarette smoking) may find other birth control products to be a safer choice. Discuss with your doctor whether the patch is appropriate for you.
Vaginal Ring. NuvaRing is a 2-inch flexible ring that contains both estrogen and progestin (etonogestrel). It is inserted into the vagina. Women can insert the ring by themselves once a month and take it out at the end of the third week to allow menstruation. It works well and may cause less irregular bleeding than oral contraceptives. Some women find it uncomfortable, and a few have reported vaginal irritation and discharge, but such problems rarely cause a woman to discontinue use. As with the patch, NuvaRing may put women who take it at higher risk for blood clots than oral contraceptives.
Implant contraception involves inserting a rod under the skin. The rod releases into the bloodstream tiny amounts of the hormone progestin. Implant Contraception
The first implant was the Norplant system, which used six rods that contained levonorgestrel. Due in part to serious complications, Norplant was withdrawn from the U.S. market in 2002. The main complication was difficulty inserting and, in particular, removing the rods. (Many women experienced scarring.) In addition, some women who used Norplant experienced heavy irregular bleeding. A two-rod implant called Jadelle is sold in other countries, but not the United States.
In 2006, the Food and Drug Administration approved Implanon, a new implant contraceptive. In contrast to Norplant:
- Implanon uses one rod, not six.
- It is not inserted as deeply into the skin.
- It uses etonogestrel, a different type of progestin than the levonorgestrel used in Norplant.
- Only specially trained health care providers are allowed to insert and remove Implanon.
Studies indicate that Implanon is safe. Irregular bleeding and headaches are the main side effects. However, some doctors are concerned that Implanon may have some of the same risks as Norplant.
Injected contraceptives are given once every 3 months. Most injectables are progestin-only. In the United States, depo-medroxyprogesterone acetate (Depo-Provera) is the only approved injected contraceptive. Depo-Provera (also called Depo, or DMPA) uses a progestin called medroxyprogesterone. Injected Contraception
Depo-Provera is very effective in preventing pregnancies. About 3 in 100 women who use it become pregnant. However, Depo also carries the risk for many mild and serious side effects. The most serious side effect is loss of bone density (see "Disadvantages"). Because of this complication, Depo-Provera should not be used for longer than 2 years.
Administering Injections :
- A physical examination is necessary before beginning the injections.
- Depo is injected into a muscle in the patient's arm or buttock. During months between injections, the hormone slowly diffuses out of the muscle into the bloodstream.
- Depo requires an injection by the doctor once every 3 months.
- If more than 2 weeks pass beyond the regular injection schedules, the woman should have a pregnancy test before receiving the next injection.
CandidacyBecause Depo-Provera does not contain estrogen, it is safe for many women who may be riskier candidates for combination oral contraceptive use, such as women over age 35, women with high blood pressure, obese women, and smokers.
Depo-Provera should not be given to women who have a history of:
- Current or past breast cancer
- Stroke or blood clots
- Liver disease
- Epilepsy, migraine, asthma, heart failure, or kidney disease (due to the fact that the drug causes fluid retention)
- Unexplained vaginal bleeding
- Risk for osteoporosis
Advantages of Depo-Provera
- Provides highly effective reversible protection against pregnancy without placing heavy demands on the user's time or memory.
- Does not increase risk for breast, ovarian, or cervical cancer. May protect against endometrial cancer.
- May be useful for women with painful periods, heavy bleeding (including heavy bleeding caused by fibroids), premenstrual syndrome, and endometriosis.
Disadvantages and Complications of Depo-Provera
- Weight gain. Most women gain an average of 5 - 8 pounds.
- Other common side effects include menstrual irregularities (bleeding or cessation of periods), abdominal pain and discomfort, dizziness, headache, fatigue, nervousness.
- Most users of Depo-Provera stop menstruating altogether after a year. Depo can cause persistent infertility for up to 22 months after the last injection, although the average is 10 months.
- Long-term (more than 2 years) use of Depo-Provera can cause loss of bone density. Depo-Provera’s label warns that the decline in bone density increases with duration of use and may not be completely reversible even after the drug is discontinued. The FDA recommends that Depo-Provera should not be used for longer than 2 years unless other birth control methods are inadequate. Some studies indicate that this bone loss may be reversible once Depo-Provera use is discontinued. Some doctors recommend that women take calcium and vitamin D supplements while on Depo-Provera.
- The injections do not provide protection against sexually transmitted diseases.
The intrauterine device (IUD) is a small plastic T-shaped device that is inserted into the uterus. An IUD's contraceptive action begins as soon as the device is placed in the uterus and stops as soon as it is removed. IUDs have an effectiveness rate of close to 100%. They are also a reversible form of contraception. Once the device is removed, a woman regains her fertility. Intrauterine Devices (IUDs)
Intrauterine Device FormsTwo types of intrauterine devices (IUDs) are available in the United States:
- Copper-Releasing (ParaGard). This type of IUD can remain in the uterus for up to 10 years. Copper ions released by the IUD are toxic to sperm, thus preventing fertilization.
- Progestin-Releasing (Mirena). This type of IUD can remain in the uterus for up to 5 years. Mirena is also known as a levonorgestrel-releasing intrauterine system, or LNG-IUS. Levonorgestrel impairs sperm motility and viability, thus preventing fertilization. LNG-IUS is long-acting, safe, very effective in preventing heavy bleeding, and helps reduce cramps. In fact, some doctors describe it as a nearly ideal contraceptive. In addition to being a contraceptive, it is approved as a treatment for heavy menstrual bleeding.
Inserting an Intrauterine DeviceWith some exceptions, an intrauterine device (IUD) can be inserted at any time, except during pregnancy or when an infection is present. It may be inserted immediately postpartum or after elective or spontaneous miscarriage. It is typically inserted in the following manner by a trained health professional:
- A plastic tube containing the IUD (the inserter) is slid through the cervical canal into the uterus.
- A plunger in the tube pushes the IUD into the uterus.
- Attached to the base of the IUD are two thin but strong plastic strings. After the instruments are removed, the health care provider cuts the strings so that about an inch of each dangles outside the cervix within the vagina.
- They enable the user or health care provider to check that the IUD is properly positioned. (Because the IUD has a higher rate of expulsion during menstruation, the woman should also check for the strings after each period, especially if she has heavy cramps.)
- They are used for pulling the IUD out of the uterus when removal is warranted.
Candidates for the Intrauterine DeviceIntrauterine devices are an excellent choice of contraception for women who are seeking a long-term and effective birth control method, particularly those wishing to avoid risks and side effects of contraceptive hormones. The LNG-IUS may be better suited for women with heavy or regular menstrual flow.
Around the time of insertion and shortly afterwards, women should be considered at low risk for sexually transmitted disease (mutually monogamous relationship, using condoms, or not currently sexually active).
Women with risk factors that preclude hormonal contraceptives should probably avoid progestin-releasing IUDs, although the progestin doses are much lower with LNG-IUS and probably do not pose the same risks.
Women with the following history or conditions may be poor candidates for IUDs:
- Current or recent history of pelvic infection (the risk of pelvic inflammatory disease is higher for all women who have multiple sex partners or who are in non-monogamous relationships--not just those with IUDs)
- Current pregnancy
- Abnormal Pap tests
- Cervical or uterine cancer
- A very large or very small uterus
- The IUD is more effective than oral contraceptives at preventing pregnancy, and it is reversible. Once it is removed, fertility returns. (Studies have found no adverse effects on fertility with the current IUDs.)
- Unlike the pill, there is no daily routine to follow.
- Unlike the barrier methods (spermicides, diaphragm, cervical cap, and the male or female condom), there is no insertion procedure to cope with before or during sex.
- Intercourse can resume at any time, and, as long as the IUD is properly positioned, neither the user nor her partner typically feels the IUD or its strings during sexual activity.
- It is the least expensive form of contraception over the long term.
- The progestin-releasing LNG-IUS (Mirena) is now considered to be one of the best options for treating menorrhagia (heavy menstrual bleeding). (However, irregular breakthrough bleeding can occur during the first 6 months.)
- The copper-releasing IUDs do not have hormonal side effects and may help protect against endometrial (uterine) cancer.
Complications of Specific Intrauterine DevicesMenstrual Bleeding. Both intrauterine device (IUD) forms have effects on menstruation, although they differ significantly by type:
- Copper releasing IUDs can cause cramps, longer and heavier menstrual periods, and spotting between periods. Prescription medications are available to control the bleeding and pain, which, in any event, usually subside after a few months.
- Progestin-releasing IUDs produce irregular bleeding and spotting during the first few months. Bleeding may disappear altogether. (This characteristic is a major advantage for women who suffer from heavy menstrual bleeding but may be perceived as a problem for others.)
Expulsion. About 2 - 8% of IUDs are expelled from the uterus within the first year. Expulsion is most likely to occur during the first 3 months after insertion. Expulsion rates may be higher than average if the IUD is inserted immediately after delivery of a child. In 1 in 5 cases, the woman fails to notice that the device is gone, and thus faces the risk of unintended pregnancy. The risk for expulsion is highest during menstruation, so women should be sure to check the strings to make sure the IUD is in place.
Pelvic infections . What was thought to be an increased risk of pelvic inflammatory disease has proven not to be true. The risk does not seem to be any greater than the risk in the general population The risk for infection may be increased around the time of insertion of the IUD, but routine screening before insertion is generally not recommended. There is also no evidence that IUD usage increases the risk of HIV infection.
Effects on Pregnancy.
- None of the current IUDs increase the risk for infertility. Women with a history of using an IUD are no more likely to be diagnosed with infertility than those who have not used IUDs. This seems to be true both for women who have never been pregnant or women who have been pregnant previously.
- In the very unlikely event that a woman conceives with an IUD in place, however, there is a higher risk of an ectopic pregnancy or miscarriage. Ectopic pregnancy is when the fertilized egg implants outside of the uterus. Most ectopic pregnancies occur in the fallopian tubes. However, overall, women who use IUDs have a significantly lower rate of ectopic pregnancies than women who do not use any contraception. Even for women who have a history of ectopic pregnancies when not using contraception, the IUD is considered safe and may even lower their risk for another one.
Perforation. A potentially serious complication of the IUD is the accidental perforation of the uterus during insertion or later perforation if the IUD shifts position. Such an occurrence is very rare, particularly if the doctor is experienced with insertion.