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How Long After Unprotected Sex Can I Take Emergency Contraceptives?

You can effectively use emergency contraceptives for three to five days after unprotected sex, depending on the pill you choose. Understand your options and how they work so you can pick the right pill for your needs.

How do Emergency Contraceptives Work?

Emergency contraceptives, also referred to as the “morning after pill”, help prevent pregnancy after unprotected sex. Emergency contraceptive pills prevent ovulation so an egg will not be released while sperm is present. These pills may also help stop sperm from fertilizing the egg if ovulation has already occurred.

If a fertilized egg has implanted in the uterus before the emergency contraception was used, this pill will not impact the pregnancy. This is not an abortion pill. It makes pregnancy less likely to happen but does nothing to an existing pregnancy.

When to Use Emergency Contraception

You should use emergency contraception after sex if you did not use birth control or if your birth control failed. There are many ways that birth control can fail.

  • The condom broke or came off during sex.
  • You forgot to take your birth control pill.
  • You were more than two weeks late getting the birth control shot.
  • You put the vaginal birth control ring in late.
  • Your birth control patch came off or you put it on late.
  • You used improper timing with the natural planning method and had sex on fertile days.
  • The diaphragm tore or slipped out of place.
  • Your cervical cap slipped off the cervix or broke.

Emergency contraception should not be your primary form of birth control. This is intended only for use in accidental cases where you realize that you are not properly protected from pregnancy.

You must use emergency contraception shortly after having unprotected sex. Most forms of emergency contraception will only work three to five days after you’ve had sex, and some become less effective over time.

What Types of Emergency Contraceptives Are There?

There are two primary options for emergency contraception.

  • Plan B One-Step: This pill uses levonorgestrel to delay ovulation, make it more difficult for the egg to become fertilized, and prevent the egg from attaching to the uterine wall. You must take this pill within three days of having unprotected sex. It becomes less effective over time.
  • Ella: Ella is a nonhormonal pill that uses ulipristal to prevent pregnancy. This blocks important hormones necessary for contraception. Ella is effective for up to five days after unprotected sex. Its effectiveness does not diminish over time.

It’s important to consider your options carefully and choose the best morning after pill for your needs. Consider these facts:

  • Plan B One-Step is most effective for women who weigh less than 165 pounds. Success with this pill is limited for women over 176 pounds.
  • Ella is more effective than other emergency contraceptive pills for women who weight 155 pounds or more. If you weight over 195 pounds, Ella may not work.
  • You should not use Ella if you typically use hormonal birth control like the pill, patch, shot, or ring, as it can impact the effectiveness of these birth control methods.
  • If you use Ella once and need emergency contraception again before your next period, you should not switch to Plan B One-Step. Use Ella again.
  • Ella is best for women who are close to ovulation.

What Side Effects Occur With Emergency Contraception?

Some common side effects that you may experience include:

  • Headaches
  • Nausea
  • Stomach pain
  • Dizziness
  • Fatigue
  • Menstrual cramps
  • Diarrhea
  • Breast tenderness

If you have serious side effects like severe stomach pain, you should talk to your local healthcare provider as this could indicate an ectopic pregnancy. This can occur for up to a month after taking the pill.

If you vomit within two hours of taking an emergency contraception pill, you may need to take another one.

After taking emergency contraception, your period may not come on time. Women have reported getting their period early or late. However, most women will get their period within seven days of the expected date. Your flow may be heavier or lighter than usual. If you do not get your period within three weeks of taking emergency contraception, you should take a pregnancy test.

How Can I Get Emergency Contraception?

Progestin-only emergency contraception is available over the counter in most pharmacies. Ella is available by prescription only. You can contact your primary care provider for a prescription or order emergency contraception online. Nurx™ can help you get emergency contraception quickly and affordably after unprotected sex.

How to Use Emergency Contraception

Once you have chosen the right pill for your needs and received your emergency contraception, it’s easy to use. Speak with your healthcare provider about any other medications you’re taking or health conditions that you have to make sure you’re using this medication properly and in the safest way possible.

  • Take your emergency contraception pill as soon as possible after unprotected sex.
  • Contact your healthcare provider for another dose if you vomit within two hours of taking the pill.
  • If you’re on hormonal birth control, discuss proper use with your healthcare provider. You may need to stop taking your birth control for several days after using emergency contraception for it to work properly. This can decrease the effectiveness of your birth control later in the month, so you may need to use backup birth control.

Can I Get Pregnant With Emergency Contraception?

It is possible for emergency contraception to fail. It makes pregnancy less likely but is not 100% effective. Studies have not shown any adverse side effects in the pregnancy or baby associated with taking emergency contraception.

Emergency Contraception Effectiveness

Though emergency contraception is not 100% effective, it greatly reduces the risk of pregnancy.

  • Plan B One-Step reduces your risk of pregnancy by 88%.
  • Ella reduces your risk of pregnancy by 85% when taken within five days of unprotected sex.

If you’ve had unprotected sex, it’s important to take steps to prevent unwanted pregnancy. Taking emergency contraceptives is a safe option.

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