Birth Control

Starting Birth Control Pills on Your Period

Key Takeaways

There's a lot of different information out there about when and how to start birth control. If you’ve been thinking about starting birth control, you need all the facts to make an informed decision about your health.

If you’re feeling overwhelmed, don’t worry, because we’ve gathered up all the information you need to know about starting birth control, whether it’s your first time taking oral contraceptives, you’re switching types, or you’re starting up again after a break. We’ll take a closer look at the two types of birth control pills, how and when to start taking them, and how long they take to become effective.

When it comes to planning when to start birth control pills, the bottom line is this:you can safely start taking your oral contraceptives at any point in your menstrual cycle. So, if you’ve just received your pills, you can start taking them right away.

Here are a few more of the most common questions people ask when choosing when to start birth control pills.

When to start birth control pills

There are three approaches that people tend to use when starting birth control pills.

1. Start immediately

This is the easiest approach. If you’re eager to get started, you can take your first oral contraceptive at any time.  Take your pill at the same time every day to ensure effectiveness. Use back up contraception like condoms for one week while the pill kicks in.

2. Start during your period

If you receive your birth control prescription while you are on your period, there’s no reason you can't start your pack that same day. Remember to use backup birth control for the first seven days as your body adjusts and your oral contraceptives become effective.

3. Start on Sunday

Some people choose to start their birth control pills on the Sunday following their period. This is due to some birth control packs beginning on a Sunday, but it’s unnecessary to start taking your oral contraceptives on any specific day in relation to your menstrual cycle. You can start on any day. Just remember to use back up protection for a week.

What day of the week should you start taking birth control pills?

The effectiveness of your birth control pills does not change depending on what day of the week you start taking them. You can start on any day.

Can you start birth control on your period?

If you are on your period when you receive your birth control prescription, you can start taking your pills that same day. Keep in mind that the timing of everyone’s natural fertility window can be highly unpredictable, so you can’t completely rely on the idea that you won’t get pregnant while on your period. You should always use some form of birth control regardless of where you are in your menstrual cycle. Make sure to use a backup birth control method for the first seven days to prevent pregnancy while taking birth control pills. You can start taking oral contraceptives at any time as long as you make sure to use protection while you wait for your birth control pills to take effect.

What do I do if I miss a birth control pill?

It can be scary to realize that you’ve missed a pill, but don’t freak out. The steps you should follow if you miss a pill can differ depending on what week of your pill pack you’re on when you miss one, and how long it’s been since you missed it. In general, you should take your missed pill as soon as you remember, but you can follow these guidelines to ensure that you’re still protected against pregnancy.

Do birth control pills protect against STIs?

While birth control pills are effective to prevent pregnancy, they don't protect against STIs. You should always make sure to put your safety first and use some form of STI prevention, especially with a new partner.

Types of birth control pills

There are two different types of birth control pills, and they differ in terms of how long it takes for them to take effect. Here are the main differences between them:

Combination pills (COCs)

Combination pills contain two hormones, estrogen and progestin, and are the most commonly prescribed form of birth control pill.

Starting combination birth control on your period

You can start taking your COCs at any time. Make sure to use additional birth control for the first seven days if you plan on being sexually active during that time.

Most COCs come in either 28-day or 21-day packs, although there are also 91-day packs available. Here’s how to take your oral contraceptives, depending on which pack you are prescribed.

28 days:

Take one pill every day for 28 days, then start a new pack. The last 4-7 pills of a 28-day pack are generally placebo pills that may contain iron or other supplements. You don’t need to take the placebos to prevent pregnancy, so you can either take them as usual or skip taking a pill on those days. Different packs may have a different number of placebos, but you should recognize them because they are a different colour. If you are unsure, please speak to your pharmacist or prescribing health care practioner.

21 days:

Take one pill every day for 21 days. Since your pack does not contain placebos, you can either not take any pills for seven days and get your period during this time, or you can immediately start a new pack of birth control pills, skipping your period.

91 days:

These packs contain three months of hormone pills and one week of placebo pills. This means that you will only get your period four times a year, which can be helpful for a number of reasons. You can also use your 28- or 21-day packs and skip the placebo pills or seven-day break between packs in order to achieve the same effect.

Progestin-only pills (POPs) 

Progestin-only pills, also called mini-pills, contain just one hormone instead of two. All POPs need to be taken at the same time every day in order to be effective.

When to start taking progestin only birth control pills

Birth control pills can take up to seven days to become effective against pregnancy, so make sure that you continue to use another form of birth control during this time. Since you need to take them around the same time every day, it’s a good idea to set an alarm or phone reminder. POPs only come in 28 day packs, and every single pill contains hormones, so you need to take all of the pills in your pack. You may get your period during the fourth week of your POPs, but you also may not have any period at all.

Other birth control options

Birth control pills aren't the only game in town when it comes to contraception. Patches, rings, IUDs, and emergency contraception (aka the morning after pill) give you lots of choice. Explore your options below:

Birth control patch

IUDs (intrauterine devices)

Emergency contraceptives

Now that you know more about birth control in general, as well as how to start birth control pills on your period, you’ll be able to choose the method that works for you and start when you want.

Want to explore your options? Start your online assessment with a healthcare practitioner through Felix today.

Medically reviewed by


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