Male birth control shot found effective, but side effects cut study short

By Susan Scutti, CNN

Updated 1833 GMT (0233 HKT) November 1, 2016

Women have many choices when it comes to avoiding pregnancy, but men have only two. According to the Centers for Disease Control and Prevention, 99% of sexually active women used at least one contraceptive method at some point between 2006 and 2010. Here's a look at a variety of birth control methods and how they each work.
Photos: Birth control methods
A woman's choice – Women have many choices when it comes to avoiding pregnancy, but men have only two. According to the Centers for Disease Control and Prevention, 99% of sexually active women used at least one contraceptive method at some point between 2006 and 2010. Here's a look at a variety of birth control methods and how they each work.
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A male condom is a thin covering worn on the penis during intercourse. It can prevent sexually transmitted diseases, and is about 82% effective at preventing pregnancy.
Photos: Birth control methods
A male condom is a thin covering worn on the penis during intercourse. It can prevent sexually transmitted diseases, and is about 82% effective at preventing pregnancy.
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During a vasectomy, a surgeon cuts the vas deferens, the tubes that carry sperm from the testicles. It has a failure rate of about 0.15% and can be reversed, but the procedure is complicated.
Photos: Birth control methods
During a vasectomy, a surgeon cuts the vas deferens, the tubes that carry sperm from the testicles. It has a failure rate of about 0.15% and can be reversed, but the procedure is complicated.
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An intrauterine device, or IUD, is a flexible T-shaped device that's inserted by a doctor into a woman's uterus. The devices block sperm and change the lining of the uterus, which may keep a fertilized egg from attaching. Pregnancy is prevented from three to 12 years, depending on the type.
Photos: Birth control methods
IUD – An intrauterine device, or IUD, is a flexible T-shaped device that's inserted by a doctor into a woman's uterus. The devices block sperm and change the lining of the uterus, which may keep a fertilized egg from attaching. Pregnancy is prevented from three to 12 years, depending on the type.
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Approved in 1960 by the Food and Drug Administration, oral contraceptives involve taking a daily pill with a combination of estrogen and a progestin. The hormones prevent ovulation and thicken a woman's cervical mucus, blocking sperm from fertilizing an egg.
Photos: Birth control methods
The pill – Approved in 1960 by the Food and Drug Administration, oral contraceptives involve taking a daily pill with a combination of estrogen and a progestin. The hormones prevent ovulation and thicken a woman's cervical mucus, blocking sperm from fertilizing an egg.
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Condoms aren't just for men. The female condom fits inside the vagina with a ring at one end that covers the cervix. When used correctly all of the time, the National Institutes of Health says, it's 95% effective, with bonus protection from sexually transmitted infections.
Photos: Birth control methods
Female condom – Condoms aren't just for men. The female condom fits inside the vagina with a ring at one end that covers the cervix. When used correctly all of the time, the National Institutes of Health says, it's 95% effective, with bonus protection from sexually transmitted infections.
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The diaphragm also fits inside the vagina but covers only the cervix, where it blocks sperm from entering the uterus. It is made of silicone and can last up to two years. A spermicide must also be used for greatest effectiveness.
Photos: Birth control methods
Diaphragm – The diaphragm also fits inside the vagina but covers only the cervix, where it blocks sperm from entering the uterus. It is made of silicone and can last up to two years. A spermicide must also be used for greatest effectiveness.
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The cervical cap is similar to a diaphragm but smaller in size and made of rubber instead of silicone. It is useful for women who find it hard to keep a diaphragm in place.
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Cervical cap – The cervical cap is similar to a diaphragm but smaller in size and made of rubber instead of silicone. It is useful for women who find it hard to keep a diaphragm in place.
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Implants are flexible matchstick-size devices that are surgically inserted into a woman's arm. They slowly release the hormone progestin into the body, preventing a woman's ovaries from releasing eggs. The protection can last several years.
Photos: Birth control methods
Implant – Implants are flexible matchstick-size devices that are surgically inserted into a woman's arm. They slowly release the hormone progestin into the body, preventing a woman's ovaries from releasing eggs. The protection can last several years.
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For women who don't want to take a pill or insert a device, the Ortho Evra birth control patch sticks to the body and releases pregnancy-preventing hormones through the skin. A woman must change her patch once a week for three weeks in a row. No patch is used in the fourth week, and then the cycle starts again.
Photos: Birth control methods
The patch – For women who don't want to take a pill or insert a device, the Ortho Evra birth control patch sticks to the body and releases pregnancy-preventing hormones through the skin. A woman must change her patch once a week for three weeks in a row. No patch is used in the fourth week, and then the cycle starts again.
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