Illustration of Plan B balanaced on a finger against a purple background
Scientifically Reviewed
Home/Cycle Matters / Birth Control

How many times can you take Plan B?

Sometimes referred to as a ‘morning-after pill’, Plan B is a type of oral emergency birth control you can take after unprotected sex or if the method you’re using fails. We’ll cover the side effects of this method, how it works, and how often you can take it. Read on to learn more…

How does Plan B work?

Plan B contains a dose of hormones that are designed to disrupt your natural hormonal levels in order to delay your ovulation. Since sperm can survive in the female reproductive system for up to five days, pushing your ovulation day back to later in the menstrual cycle can prevent pregnancy. This is how the morning after pill works.

If you take Plan B within three days of having unprotected sex it can lower your chances of getting pregnancy by 75%-89%. Unfortunately, if you’ve already ovulated before you take Plan B, this method might not work as conception can still occur. You can increase the chances of it working by taking it as soon as possible after unprotected sex. 

How often can you use Plan B?

If you’re wondering ‘how many times can I take the morning after pill’, there’s actually no set guidance. Research into this has been limited, but there’s no evidence to suggest that taking emergency contraception multiple times in a menstrual cycle is harmful. 

While there may be no significant risk to frequently taking emergency contraception, relying on these morning after pills to prevent unintended pregnancy is not as reliable as using birth control. 

If you find you’re often taking a morning after pill, you should consider using a daily oral contraceptive instead such as combined birth control pills or progestin only pills. If you find it hard to remember to take birth control pills, then you may want to consider a longer-term birth control method instead.

Keep in mind that the only birth control option that can protect you from sexually transmitted infections are condoms. These barrier methods can be a handy option when you’re not regularly sexually active, but want to prevent pregnancy.

Does taking Plan B multiple times affect fertility?

There is no evidence to suggest that taking a morning after pill has a knock-on effect on your future fertility. Initially you may notice slight changes to your cycle, but things should go back to normal pretty quickly.

Can Plan B delay your period?

Yes. Since this emergency birth control method works by pushing back your ovulation it can make your cycle longer than usual. Since it disrupts the cycle you may also get earlier periods from this method, or to experience a change in bleeding. This may mean that your next period is lighter or heavier than usual, or you may experience irregular bleeding or spotting. 

Signs that Plan B didn’t work

If your period is late and you’re worried the morning after pill didn’t work, it’s time to take a pregnancy test. These are usually reliable from the first day of your missed period. You can also read up on the signs of early pregnancy to know what to look out for, although keep in mind that symptoms such as tiredness and breast tenderness are also common signs of premenstrual syndrome

If your pregnancy test comes back negative, you may just be experiencing a longer cycle than normal due to the change in hormone levels. Keep in mind that stress can also impact the menstrual cycle so if you’re worrying about whether or not you’re pregnant, it could have a knock-on effect. That said, if you have concerns or if your period is delayed by more than a few days, it’s a good idea to talk to your healthcare provider. 

What happens if you take Plan B when pregnant?

Emergency contraceptive pills do not work in the same way as abortion pills.Taking a morning after pill will not terminate an existing pregnancy and it also will not harm the baby if you take it when you’re already pregnant.

Side effects of taking Plan B

Morning after pills are considered to be very safe to take, although you may experience some short-term side effects. Keep in mind that if you throw up within two hours of taking the pill, you should take an additional dose. Short-term side effects include:

  • Upset stomach
  • Feeling dizzy
  • Tender breasts

Where can I get Plan B?

Plan B is available without a prescription in your local drugstore or pharmacy. It may be stored behind the counter so you may have to ask for it, but you don’t need to show any ID or proof of age. You can also find it in most family planning or health clinics and at your local Planned Parenthood Health Centre.

You can order emergency oral contraception online, but keep in mind that it may not arrive in time. However, if you want to be prepared and keep a pill in your medicine cabinet, it may give you peace of mind in an emergency. 

In the UK and Europe you can also order emergency contraception online, find it in your local pharmacy or get it from your doctor.

How much does Plan B cost?

Depending on the brand you purchase you can expect to pay anything between $10 to $50. Depending on your insurance cover, emergency contraception may be included. Alternatively, you may be able to get it for free or at a reduced cost from a health center. 

Alternative methods of emergency birth control

If you have unprotected sex, you’re not limited to using Plan B, there are a selection of other options open to you. These include:

The Copper IUD

This is the most effective form of emergency contraception. A type of intrauterine device, the copper IUD is hormone-free and, as a long acting birth control method, it can also prevent pregnancy for up to 12 years after its fitted. You need to make an appointment with a healthcare professional to have the IUD fitted and removed.


This is an alternative morning after pill that’s more effective than Plan B, it works just as well when taken five days after unprotected sex. In the United States, you need a prescription to use Ella, so visit your doctor or a health clinic if you want to get hold of it. 

Birth control choice helps us make informed decisions

Finding the right birth control for you can reduce the need of emergency contraceptives like the morning after pill. You don’t have to struggle with a birth control method you find difficult to use. Talk to your healthcare provider to find the right method for you. There are more options out there than birth control pills, check out our list of contraceptive options to learn more about what’s available.

Did you enjoy reading this article?

Discover the world's first birth control app.

Jen on the roof terrace at Natural Cycles headquarters.

Written By

Jennifer Gray

Jennifer Gray is an award-winning writer with more than five years’ experience covering reproductive topics ranging from birth control to planning pregnancy. She is passionate about providing women with accurate information grounded in science they can use to take charge of their own health - while also dispelling myths that exist within the field of women’s health. She holds a Master of Science from the University of Edinburgh and currently lives in Ireland.

Jack in a suit and tie holding a microphone and giving a presentation.

Scientifically Reviewed

Jack Pearson

Dr. Jack Pearson is a previously HCPC registered Embryologist with a PhD in reproductive medicine. Prior to joining Natural Cycles leading Medical Affairs, he worked for more than 10 years in a clinical setting working at some of the busiest fertility clinics in the UK. Today he spends most of his time working with experts at the world’s leading institutions to carry out important research with the vision to further the field of female health. He earned his PhD from the University of Sheffield specializing in Sperm Metabolism and currently lives in London.

Featured Posts

Birth Control

A Birth Control App, not a Period Tracker

4 min read

Birth Control

12 Non-Hormonal Birth Control Methods and How They Work

13 min read

Birth Control

Switching Birth Control Methods: How Do I Change?

9 min read

Want to learn more about a hormone-free future?

Subscribe to our newsletter for access to our latest articles, exclusive promotions and more.

Keep reading...

Birth Control

Does birth control make you gain weight?

Our weight is something that many of us think about, whether it’s feeling the pressure to look a certain way, or out of concern for our health. It’s no wonder that there is some controversy around the topic of whether or not weight gain is caused by hormonal contraception. In this article, we’ll take a closer look at the science behind this subject and what we actually know about birth control and weight gain.

8 min read

Birth Control

7 types of birth control covered by insurance

In this post, we’re going to take a look at some of the birth control methods that are covered by insurance. We’ll look at both hormonal and non-hormonal options, as well as what options you have if you need birth control and don’t have insurance. Read on to learn more…

7 min read

Birth Control

How effective is the mini pill?

There are many different hormonal birth control methods on the market. When talking about birth control pills, most people tend to mean the combination pill. Today we’ll take a closer look at another kind of birth control pill called the mini pill, sometimes referred to as progestin-only pills or POPs.

8 min read