The morning-after pill is a type of birth control that can be used in emergency situations when typical birth control wasn’t used, failed, or in cases of non-consensual sexual intercourse (rape). This pill is most effective at preventing pregnancy when it’s taken as quickly after unprotected sex as possible. Brand names include Plan B One-Step® and ella®.
The morning-after pill is a medication that can be used as emergency contraception (birth control). Emergency contraception isn't the same as typical birth control pills that you might use daily or other forms of routine birth control. It's used in situations where your birth control has either failed or you were unable to use protection. Some situations where emergency contraception might be used can include:
There are many different brand names for the morning-after pill. The progestin-only morning-after pill is levonorgestrel (Plan B One-Step®). This medication is available over the counter. Another type of morning-after pill called ulipristal (ella®) is only available by prescription.
Other options for emergency contraception aside from the pill include the intrauterine device (IUD). There are two types of IUDs available: the Copper IUD and the Levonorgestrel IUD. These devices are placed into your uterus by a healthcare provider. IUDs can also be used for emergency contraception if inserted up to five days after unprotected sex.
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There are three main types of morning-after pill — each with popular brand names you might have heard of.
Plan B is a type of emergency contraception that's taken as one pill. For the best results, you should take Plan B as soon as possible — typically within the first three days after unprotected sex. You can take it up to five days after unprotected sex, but the effectiveness of the medication drops.
This type of morning-after pill also works by preventing ovulation. Ulipristal can be more effective than other morning-after pill options when it’s taken correctly (within the window of time when it’s most effective). People can take ulipristal up to five days after unprotected sex. The most common brand name for this medication is ella®. Your healthcare provider needs to prescribe ulipristal.
This type of emergency contraception involves taking birth control pills that contain both progestin and estrogen. Unlike a progestin-only medication like Plan B, this option is typically taken in two doses. It’s important to talk to your healthcare provider or pharmacist about the exact dosage (amount of the medication) you'll need and how far apart you should take the two medications. When you use combination birth control as an emergency contraception option, you’re taking a typical birth control pill at a higher dose. This isn’t something you should do without talking to your provider because different brands of birth control can change the amount you need to take.
This type of emergency contraception involves taking extra pills from a regular birth control pack. It's referred to as the Yuzpe regimen. This method involves combining pills from an available birth control pack to total 100mcg of ethinyl estradiol and 0.5mg levonorgestrel. A second dose is then repeated in 12 hours. It’s important to know that this regimen is less effective and less well-tolerated than other forms of emergency contraception. While the most common side effects include nausea and vomiting, taking extra birth control pills can cause more serious side effects in some people. It increases your risk of blood clots. It should only be considered in cases where other forms of emergency contraception aren't readily available.
The morning-after pill doesn’t reverse pregnancy. Instead, it's a type of emergency birth control that prevents pregnancy. The main way the morning-after pill works is by preventing ovulation. Ovulation is a part of your normal reproductive cycle. This is the phase when your ovaries release an egg that can then be fertilized by sperm and begin the fetal development process. If you don’t ovulate, you can't get pregnant.
When you’re thinking about how effective the morning-after pill is at preventing pregnancy, it’s important to factor in time. This is key to the medication’s effectiveness. All forms of the emergency contraception pill are more effective the sooner you take it. You don't need to wait to take these medications until the next day — despite the name “morning-after pill.”
There are certain time frames for each type of morning-after pill. The progestin-only option should be taken within the first 72 hours (three days) after unprotected sexual intercourse. The ulipristal and combined options can be taken up to 120 hours (five days) after sex.
Each day you wait outside of these recommended windows of time makes the medication less effective.
You don't need to wait until the next morning to take the morning-after pill. Emergency contraception pills are most effective at preventing pregnancy when they’re taken as quickly as possible after unprotected sexual intercourse. The amount of time you have can vary between different medications.
Even though there isn’t a set restriction on how many times you can take the morning-after pill, you shouldn't use it as routine birth control. This type of birth control is meant to be used in emergency situations when your birth control has failed, wasn't used or in cases of non-consensual intercourse.
If you take the morning-after pill in the immediate time window after having unprotected sex, it can be very effective. But it doesn’t always work. Emergency contraception medications become less effective the longer you wait before taking them. One of the main signs that a morning-after pill hasn’t worked is a missed menstrual period. If your period is more than seven days (a week) later than you expected, take a pregnancy test.
For many people, there are no serious side effects of the morning-after pill. Some symptoms of taking a morning-after pill (Plan B One-Step® or Ella®) can include:
The side effects of the morning-after pill are mild for most people. But if you notice more severe symptoms or have concerns after taking the morning-after pill, reach out to your healthcare provider.
You might experience light bleeding — called spotting — after taking the morning-after pill. Even though this doesn’t happen to everyone who takes the morning-after pill, it isn’t something that should worry you. If you notice that the bleeding is heavier or happens after you’ve missed a period, reach out to your healthcare provider. Spotting that happens after a missed period could be implantation bleeding. This light bleeding happens early during fetal development when the embryo embeds itself into the lining of your uterus (endometrium).
The morning-after pill can cause your next period to be irregular. If your period is late or abnormal, contact your healthcare provider and consider taking a home pregnancy test. Your provider will advise you on your next steps if your menstrual cycle doesn’t return to normal.
The morning-after pill isn't a permanent form of birth control. It won't harm your chances of getting pregnant in the future or impact your fertility. These medications (Plan B One-Step®, ella® and other generic options) are a temporary way to prevent pregnancy — they aren’t long-term forms of birth control.
In most cases you won’t need to see your healthcare provider after taking the morning-after pill. However, if you haven’t gotten your period within a week of when you expect it or you experience unusual bleeding, it’s often a good idea to talk to your healthcare provider. A missed period is one of the earlier signs of pregnancy.
It’s also important to remember that the morning-after pill won't protect you from sexually transmitted infections (STIs). If you have any concerns that you might have been exposed to an STI, reach out to your provider.
The morning-after pill is designed to be taken shortly after unprotected sex to prevent pregnancy. It's not meant to be regular birth control. Talk to your healthcare provider about your options for birth control to find an option that works best for your lifestyle.
There's research that suggests that your weight can impact how effective the morning-after pill will be for you. People with a higher body mass index (BMI) may not experience the same level of effectiveness when using the morning-after pill as people with a lower BMI. One type of emergency contraception that's highly effective at any weight is an intrauterine device (IUD).
The Plan B One-Step® pill and other progestin-only forms of emergency contraception are available over the counter. However, ulipristal (ella®) is a prescription-only medication. You should also talk to your healthcare provider before taking combined birth control pills to make sure you take the correct dosage (amount).
A note from Cleveland Clinic
The morning-after pill is a form of emergency contraception (birth control) that’s meant to help prevent pregnancy. This medication doesn't end an already established pregnancy. If you take a morning-after pill, it’s important to remember that the medication will be the most effective the sooner you take it. You typically have between three to five days after unprotected sex when the morning-after pill is most effective at preventing pregnancy. If you have any questions about emergency contraception, talk to your healthcare provider.
Last reviewed by a Cleveland Clinic medical professional on 07/01/2022.
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