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 future pregnancy plans.
Hormonal methods of birth control (contraception) contain female hormones in the form of either estrogen and progestin, or progestin only. They are a safe and reliable way to prevent pregnancy for most women and include an implant, an intrauterine device (IUD), injections, pills, a vaginal ring, and a skin patch. IUD or coil is a small, often T-shaped birth control device that is inserted into a woman's uterus to prevent pregnancy.
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)
- How long the drug or device works
- Whether and how it affects your monthly period
- Type and frequency of side effects
- 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. As no birth control is perfect, you must balance the advantages and disadvantages of the different options and decide which method is best for you.
This article focuses on the birth control shot option and discusses what you need to know about it.
What is the birth control shot?
The birth control shot is an injection given to a woman or girl every 3 months in the upper arm or buttock, to help prevent pregnancy. The birth control shot contains a long-acting form of the female hormone, progestin that plays a role in the menstrual cycle and pregnancy. Hormones are chemicals that control how different parts of your body work. The shot prevents pregnancy by keeping the ovaries from releasing eggs. It also causes cervical mucus to thicken and the lining of the uterus to thin. This keeps sperm from reaching and fertilizing an egg.
Where is the birth control shot available?
The birth control shot must be prescribed and is given every 3 months in a doctor's office or family planning clinic. However, not all of the birth control shot options are available in the United States. In fact, the only birth control shot that you can get in the US is the Depo-Provera injection. The other injectable birth control options are available in South and Central America; Asia, Europe and Africa; but for the purposes of this article, let us take a quick look at the Depo-Provera birth control shot.
Depo-Provera birth control shot
The Depo-Provera birth control shot is also known as the Depo shot or DMPA (depot medroxyprogesterone acetate). It is injected deep into a muscle, such as in the buttock or upper arm, or under the skin. With either dose, the injection is given every three months to deliver the progestin, in the form of medroxyprogesterone, a female hormone that helps regulate ovulation (the release of an egg from an ovary) and menstrual periods.
In order to have continuous pregnancy protection, you must get your Depo shot every three months. There are two versions available, the Depo-Provera shot and the newer version, Depo-subQ Provera injection. So, it is recommended that you discuss the suitable shot with your doctor.
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.
Depo-Provera is very effective at preventing pregnancy, with a pregnancy failure rate of less than 1 percent when repeat injections are given on time. It has been approved by the US Food and Drug Administration (FDA), to help treat a condition known as endometriosis; where tissue similar to the lining of the uterus or womb starts to grow in other places, such as the ovaries and fallopian tubes. Outside the uterus, the tissue thickens and bleeds, just as the normal 3-month period and there is no way to know ahead of time if you will have any of these side effects.
How does the birth control shot work?
The hormone progestin in the birth control shot works by preventing ovulation (the release of an egg during the monthly cycle). If a woman or girl doesn't ovulate, she cannot get pregnant because there is no egg to be fertilized. It starts to work immediately if you get it within the first 5 days of your menstrual period.
The progestin also thickens the mucus around the cervix (a cylinder-shaped neck of tissue that connects the vagina and uterus). This makes it hard for sperm to enter the uterus and reach any eggs that may have been released. The progestin also thins the lining of the uterus so that an egg will have a hard time attaching to the wall of the uterus.
How well does the birth control shot work?
The birth control shot is an effective birth control method and the Depo-Provera shot is 99% effective in preventing pregnancy. Over the course of a year, about 6 out of 100 typical couples who use the birth control shot will have an accidental pregnancy. The chance of getting pregnant increases if a woman or girl waits longer than 3 months to get her next shot.
In general, how well each type of birth control method works depends on a lot of things. These include whether a person has any health conditions or is taking any medicines that might affect its use. It also depends on whether the method is convenient and whether the person remembers to use it correctly all of the time.
Are there any side effects with the birth control shot?
The side effects suffered by women and girls who use the birth control shot include the following:
- Irregular menstrual periods, or no periods at all
- Changes in appetite
- Weight gain
- Unwanted facial and body hair
- Hair loss
- Loss of bone density or osteoporosis
- Belly pain or discomfort
- Abnormal vaginal discharges and inflammation of the vagina or vaginitis
- Pelvic and breast pain, rashes, hot flashes, swelling
- Breakthrough bleeding
- Less interest in sex
Changes to your menstrual cycle are the most common side effects. You may have irregular bleeding or spotting. After a year of use, about 50% of women will stop getting their periods. If this happens to you, your period should come back when you stop getting the shots.
Long-term use of Depo-Provera may lead to loss of bone mineral density (the amount of bone mineral in bone tissue), which makes you more likely to get osteoporosis (a condition that weakens bones, making them fragile and more likely to break). Your chances are even higher if you have taken the shot for longer than 2 years, especially if the condition runs in your family, you drink a lot, smoke or have other risk factors for the condition.
The FDA has issued a safety warning about the use of the Depo-Provera birth control shot. Studies link this shot to a loss of bone density in women, although bone density may recover when a woman is no longer getting the shot.
Doctors are not sure how this type of shot may affect the bone density of teen girls in the future, though. Girls who are considering the shot should talk to their doctors about it and make sure that they get enough calcium each day. Those who smoke should be sure to let their doctors know, because smoking may be connected to this bone density loss.
Women may notice a decrease in fertility for up to a year after they stop getting the birth control shot. However, the shot does not cause permanent loss of fertility and most women can get pregnant after they stop getting the shot.
Who can use the birth control shot?
Women, girls and nursing mothers, who have trouble remembering to take birth control pills and who want extremely good protection against pregnancy may want to use the birth control shot. However, not all women and girls can or should use the birth control shot. Some medical conditions make the use of the shot less effective or more risky. You should not get the birth control shot and should talk to their doctors if you suffer from the conditions.
Who shouldn’t get the birth control shot?
The birth control shot is suitable for most women, but you should not get it if you have:
- Unexplained vaginal bleeding
- Liver disease
- Breast cancer
- Blood clots
- Suspect you may be pregnant
Your doctor will be cautious about giving it to you if you are a teenager, or if you have:
- A history of depression
- A history of heart attack or stroke
- Osteoporosis (low bone density) or a high risk for it
Is there a birth control shot for men?
A birth control shot for men shows some promise, but researchers are still struggling to improve its effectiveness and deal with severe side effects caused by the injections. Only four pregnancies occurred among 266 men receiving the treatment, which is an effectiveness rate comparable to other contraceptive methods, according to results from a new international clinical trial (a research program conducted with patients to evaluate a new medical treatment, drug, or device). But the men also experienced mood swings and depression so frequently that a safety review committee halted the study early, the researchers reported.
No further development is planned for this particular birth control shot for men, but the clinical trial showed that such an injection can suppress sperm counts and prevent pregnancy, according to the department of reproductive health and research of the World Health Organization.
Does the birth control shot help prevent STDs?
No, the birth control shot does not protect against STDs (Sexually Transmitted Diseases). In fact, some studies show that the birth control shot may possibly increase the risk of getting certain STDs, although scientists do not understand why. Couples having sex must always use condoms along with the shot to protect against STDs.
How much does the birth control shot cost?
Each injection (3 months' worth of birth control) costs between $0 and about $150. Many health insurance plans cover the cost of birth control shots and doctor's visit. Family planning clinics, such as Planned Parenthood may charge less.
When should I call the doctor?
If you use the birth control shot, call your doctor if you:
- might be pregnant
- have a change in the smell or color of your vaginal discharge
- have unexplained fever or chills
- have belly or pelvic pain
- have pain during sex
- have heavy or long-lasting vaginal bleeding
- have yellowing of the skin or eyes
- have severe headaches
- feel depressed
- have signs of a blood clot, such as lower leg pain, chest pain, trouble breathing; weakness, tingling, trouble speaking, or vision problems
The birth control shot is a prescribed injection given every 3 months and one of a number of methods available to help prevent pregnancy. The only birth control shot available in the US is the Depo-Provera injection. The shot is effective in preventing pregnancy, but also known to cause serious side effects, including loss of bone density. It is therefore essential to discuss fully the side effects and your suitability for the birth control shot with your doctor, before deciding whether or not the shot is right for you.
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