The least and most effective types of birth control for preventing pregnancy
- No birth control method is a guarantee against pregnancy, and some types work better than others.
- Missing a dose or taking birth control with certain medications may increase your risk of pregnancy.
Can you get pregnant while using birth control? The short answer is yes. And it happens quite often.
Almost half of all pregnancies in the United States are unplanned. And for almost half of those unplanned pregnancies, couples were using some form of contraception, says Dr. Mary Jane Minkin, gynecologist and clinical professor of obstetrics, gynecology, and reproductive sciences at Yale School of Medicine.
No contraceptive is 100% effective — all the same, using some type of birth control does a lot more to prevent pregnancy than not using any at all.
The key to effectively preventing pregnancy lies in using your chosen method correctly and using a backup method if you:
- Fall behind on doses
- Vomit after taking your dose
- Take certain medications
When choosing the right birth control method for you, you might start by reviewing which options best suit your lifestyle and needs – but keep in mind that some birth control methods prove more effective than others.
In light of changing legislation and new restrictions around abortion, effective birth control is even more essential for millions of people in the United States.
Here are the most popular methods of birth control and the chances of pregnancy you face with each.
Perfect use vs. typical use
"Typical use" refers to how most people use birth control. Sometimes, things don't happen as planned. The condom might not be on properly, for instance, or you might forget a pill or two. "Perfect use," on the other hand, would mean taking your pill at exactly the same time every day, and a condom worn properly every single time.
IUD
What is it? The IUD, short for intrauterine device, is a T-shaped piece of flexible plastic roughly the size of a quarter. A clinician inserts the IUD in your uterus, where it can prevent pregnancy for up to 10 years, depending on the type of IUD. It can be placed during an office visit or immediately after you give birth.
There are two main types of IUD: non-hormonal and hormonal.
- Non-hormonal IUDs use copper to prevent pregnancy for up to ten years. Copper changes how sperm cells move, preventing them from reaching the egg. And if sperm can't reach an egg, you can't get pregnant.
- Hormonal IUDs release progestin to prevent ovulation, so there's no egg for sperm to fertilize. This type of IUD can last up to seven years, depending on the brand. The four options in the United States include Mirena, Kyleena, Skyla, and Liletta.
How effective is it? Both non-hormonal and hormonal IUDs are 99% effective at preventing pregnancy. A healthcare professional handles the insertion, so you don't need to remember a dose, or do anything at all with this method.
Anyone with a uterus can use an IUD for birth control — even teenagers and people who've never been pregnant.
The copper IUD, Mirena, and Liletta are effective as soon as they're placed. The Kyleena and Skyla start working immediately only if inserted during the first seven days of your menstrual cycle. Otherwise, you'll want to use a backup method like condoms for seven days.
What are the risks if you get pregnant? "In the rare circumstance that you become pregnant while using an IUD, there's a small increased risk of ectopic pregnancy," says Dr. Becky Mawson, Clinical Lead and General Practitioner at contraceptive review platform The Lowdown.
An ectopic pregnancy happens when a fertilized egg implants outside the uterus, where it can't survive. This condition is fairly rare — it only happens in approximately 1 in 90 pregnancies — but it may become life-threatening if left untreated.
Note: Some types of birth control, like IUDs, involve a slightly increased risk of ectopic pregnancy if you happen to conceive while using that method of birth control. Still, your overall risk of ectopic pregnancy is still lower when using any type of birth control. That's because birth control greatly reduces your chances of becoming pregnant at all.
Implant
What is it? A contraceptive implant is a flexible piece of plastic, roughly the size of a matchstick, that's placed under the skin in your upper arm by a healthcare professional. The implant releases a low dose of progesterone to prevent pregnancy for up to three years.
How effective is it? The implant is 99% effective, making it one of the safest options for preventing pregnancy. Since a doctor places it, there's no "perfect" versus "typical use."
You can get the implant postpartum before you leave the hospital or birthing center. If you receive the implant within the first five days of starting your menstrual cycle, you'll be protected from pregnancy immediately. If you get the implant any other day, you'll want to use a backup method, like condoms, for seven days.
What are the risks if you get pregnant? The implant can increase your risk of ectopic pregnancy if you happen to get pregnant while on this form of birth control.
Depo–Provera shot
What is it? You receive this progestin-based injection, also known as the Depo shot, once every three months. In other words, it does involve some ongoing upkeep.
Your doctor might recommend Depo-Provera if you don't want to take a pill every day, or if you have health issues like anemia, seizures, or sickle cell disease. You can get your first injection postpartum before you leave the hospital or birthing center.
You can become pregnant 12 weeks after your most recent shot. That said, in some cases it can take up to two years to conceive after stopping Depo-Provera.
How effective is it? With typical use, the Depo-Provera shot is 94% effective at preventing pregnancy. When removing human error, like not getting your injection on time, it's 99% effective.
If your period started within the last seven days, it's fully effective as soon as you get the shot. Otherwise, you should use a backup contraceptive method for a week.
What are the risks if I get pregnant? Pregnant people overall are 5 times more likely to experience a blood clot than those who are not pregnant. The Depo shot can increase your risk of blood clots, which can be potentially dangerous to you or the fetus.
Quick tip: The CDC has a free Blood Clot Prevention Checklist you can use to better understand your risk, as well as symptoms of blood clots.
Vaginal ring
What is it? The vaginal ring, sometimes called the NuvaRing, is a soft plastic ring you place in your vagina monthly. It releases estrogen and progestin for a month to prevent ovulation and pregnancy.
How effective is it? The ring is 99% effective with perfect use and 91% effective with typical use. Some people switch their ring too late or take it out during sex and forget to put it back in within two hours, lowering its effectiveness. However, unlike the pill, the ring still works just as well if you experience vomiting or diarrhea while using it.
You can keep new vaginal rings at room temperature, away from direct sunlight, or in your refrigerator. You'll want to avoid oil and silicone-based lubricants, as these can make your birth control less effective.
You'll be protected against pregnancy immediately if you insert it in the first five days of your period. Otherwise, you should use a backup form of protection for seven days.
What are the risks if I get pregnant? There are none associated with the NuvaRing – even your risk of ectopic pregnancy is lower while on this birth control.
Birth control patch
What is it? The birth control patch releases estrogen and progestin for a month to prevent ovulation and pregnancy. You place the patch on your skin like a sticker once a week for three weeks. You skip the patch on week four so you can have a period.
How effective is it? The patch is 99% effective with perfect use and 91% with typical use. To improve its effectiveness, make sure your patch is securely attached to your skin and change it at the same time every week.
As with other methods, you'll be protected against pregnancy immediately if you apply the patch in the first five days of your period. Otherwise, you should use a backup form of birth control for seven days.
What are the risks if I get pregnant? There is no increased risk associated with pregnancy while using the patch.
Birth control pills
What is it? There are two types of birth control pills: one contains both estrogen and progestin and one contains only progestin (the minipill). Both can stop or reduce ovulation. You can also use some types of birth control pills to skip your period.
How effective is it? The pill is 99% effective with perfect use and 91% with typical use. You can increase its effectiveness by taking it at the same time each day. Setting an alarm on your phone can help you stay on track.
Vomiting, diarrhea, antibiotics, antifungals, and other medications can weaken the pill's effectiveness. Purging within a few hours of taking the pill can remove some of it from your body, so it's a good idea to ask your clinician if you should take a second dose after vomiting or diarrhea.
Certain enzyme-inducing medications can also speed up your body's absorption of contraceptive hormones. This reduces the level of those hormones in your bloodstream and makes your birth control less effective.
Note: You may have heard that eating grapefruit can mess with your birth control. While this is uncommon, some clinicians recommend avoiding grapefruit while using the NuvaRing or birth control pills, just in case.
What are the risks if I get pregnant? If you get pregnant while taking the pill, you have a slightly increased risk of ectopic pregnancy than if you became pregnant while not taking the pill. Researchers haven't found any evidence to suggest birth control pills can cause birth defects, however.
"Previously, there was concern that a pregnancy conceived while on birth control pills would have an increased risk of congenital malformations, but that seems unlikely from the data we have today," Minkin says.
Condom
What is it? Two types of condoms exist: You use external condoms to cover the penis, and you use internal condoms inside the vagina.
Both types work by creating a barrier that prevents sperm from fertilizing an egg. They also help lower your risk of sexually transmitted infections (STIs).
How effective is it? The basic condom is 98% effective at preventing pregnancy with perfect use and 85% effective with typical use. Internal condoms are 95% effective with perfect use and 79% effective with typical use.
While most people think they know how to put on a condom correctly, it's worth double-checking your technique, given that 15 out of 100 people who rely on condoms for birth control get pregnant every year.
What are the risks if I get pregnant? There are no known health risks associated with condoms and pregnancy.
Just make sure you and your partner don't have a latex allergy if you're using latex condoms. Among the general population, 4% of people have a latex allergy, which can be life-threatening.
Diaphragm with spermicide
What is it? A diaphragm is a reusable, shallow cup that goes inside the vagina and covers the cervix during sex to prevent pregnancy. You cover the diaphragm with spermicide, insert it before sex, and remove it six hours after sex.
How effective is it? While adding spermicide to a diaphragm increases its effectiveness, it's still much less effective at preventing pregnancy than other birth control methods. A diaphragm is 92%-96% effective with perfect use and spermicide.
To increase its efficacy, add more spermicide if you placed the diaphragm three or more hours ago. Keep in mind you need to leave the diaphragm in for at least six hours after sex to prevent pregnancy.
What are the risks if I get pregnant? There are no known health risks associated with diaphragms or spermicide and pregnancy.
Sterilization
What is it? A vasectomy, sometimes referred to as male sterilization, and tubal ligation, sometimes called female sterilization, are permanent surgical procedures used to prevent pregnancy.
How effective is it? Both vasectomies and tubal ligations are 99% effective. Pregnancy only occurs after tubal ligation in 18 out of 1,000 people and after vasectomy in 1 in 10,000 people. There are no doses to remember and nothing you need to renew to prevent pregnancy.
What are the risks if I get pregnant? If you conceive after having a tubal ligation, there is a risk of ectopic pregnancy. If you think you might be pregnant after a tubal ligation, contact your clinician immediately.
It's also worth noting that while tubal ligation can sometimes be reversed, the procedure is complicated and doesn't always work. Insurance may not cover this procedure, either.
Insider's takeaway
While it's possible to get pregnant while using birth control, some methods prevent conception more effectively than others.
Mawson recommends choosing the option that works best with your lifestyle. Will you remember to take a pill around the same time every day, or would an IUD that stays put for several years be a better fit?
"Using a method that doesn't suit you and your body can really impact your life and mental health. If you're not satisfied with your contraception, you're more likely to stop using it properly, making it less effective," Mawson says.