Shocked african american woman reading leaflet before taking contraceptive pills, sitting on couch at home

Birth control pill: everything you need to know

Combined birth control pills contain two hormones, estrogen, and progestin. ‘Mini-pills’, or progestin-only pills, only contain progestin.

The full name for the combined pill is Combined Oral Contraceptive Pill or COCP. The full name for the ‘mini-pill’ is Progestin-Only Pill or POP. But most people just call them both ‘the pill’.

How well does it work?

Failure rate

Typical use: 7 percent
Perfect use: less than 1 percent
The combined pill works very slightly better than the mini-pill for non-breastfeeding women. In breastfeeding women, who are the main users of POPs, POPs are highly effective (less than 1% pregnancy rate even in typical use)

(Read more about what ‘failure rate’ means in how well does it work?)

Pros

Very good at preventing pregnancy
You can stop taking it to try and get pregnant whenever you like
COCs make periods lighter, reduce menstrual cramps
No interruption during sex
You don’t need the man to cooperate

Cons

You’ve got to take it every day – miss a day and you could get pregnant
POPs can make periods irregular and unpredictable, with some women developing amenorrhea.
It doesn’t protect against sexually transmitted diseases
It can be expensive
You need to see a health care provider and get a prescription

How do birth control pills work?

Combined birth control pills, with two hormones, stop you from producing an egg. At the same time, they make the mucus around your cervix thicker so the sperm can’t get through.

Mini-pills, with only one hormone, work just because of this thickening of the mucus. But they also stop you from producing an egg some of the time too, depending on the dose.

Who shouldn’t take birth control pills?

You shouldn’t take any kind of birth control pills if:

You’ve had breast cancer
You’ve got blood clot problems that aren’t being successfully treated
You think you’re pregnant. (But if you’re on the pill and still got pregnant, it won’t have harmed the baby – read more in pregnancy FAQs)
Taking certain medications, such as TB drugs or drugs to treat seizures

Who shouldn’t take combined birth control pills, rather than mini-pills?
You shouldn’t take combined birth control pills, if:

You’ve had a long period of bed rest
You have migraine headaches with auras, which affect what you see
You’ve inherited blood-clot disorders, have had blood clots, or inflamed veins
You’ve had a heart attack, a stroke, or, angina
You’ve got serious heart valve problems
You’ve got lupus
You’ve had serious liver disease or liver cancer
You’ve got very bad diabetes
You’ve got high blood pressure
You’re a smoker and are 35 or older
Had a baby less than 3 weeks ago
Breastfeeding a baby less than 6 months old
Have gallbladder disease
You’re taking certain medications, such as TB drugs or drugs to treat seizures

This is why you need to see a health care provider and get a prescription before you go on the pill.

What should you do if you miss a pill?

Check the instructions for your brand of pill.

You need to take the pill at the same time every day although it’s okay if you take it three hours later or earlier. If you miss a pill, you should take the next one as soon as you can. You carry on taking the pill as normal. But at the same time, you need to use a backup birth control method, because otherwise, you could get pregnant.

Combined birth control pill: If 1 or 2 pills are missed (or if a new pack is started 1-2 days late), users should take a hormonal pill as soon as possible, with no backup method needed. If 3 or more pills are missed (or if a new pack is started 3 or more days late), users should take a pill as soon as possible and use a backup method for the next 7 days.
Mini-pill: if you take it more than three hours late, you need a backup for two days.

Back-ups might be a condom, female condom, diaphragm, or sponge. If you’ve had sex and think you might not have been properly protected, you can use emergency contraception.

What can stop the pill from working properly?

Vomiting or diarrhea can stop the pill from working properly – check the instructions for your brand of pill.

If you vomit within two or three hours of taking the pill your body might not have absorbed it properly. You should take another pill. But if you keep vomiting, you should use a backup birth control method for seven days after you get better.

Do the same if you’ve had severe diarrhea for more than 24 hours.
Certain medicines might stop the pill from working as well. They include medication for HIV, and epilepsy, and the herbal remedy St John’s wort.
You need to check with a healthcare professional if you’re taking medicines along with the pill.

How safe are birth control pills?

After a few months, most women find the pill doesn’t give them any side effects.

When you stop taking the pill it can take one or two months before your period cycle returns to how it used to be before taking the pill. If you had irregular periods before taking the pill, they might be even more irregular when you stop. Talk to your healthcare provider if you’re worried about this.
During the first two to three months, you may have:

Tender breasts
Nausea
Vomiting
Bleeding between periods (more likely with the progestin-only or ‘mini-pill’)

If you take your pill every evening or at bedtime, you’re less likely to experience nausea and vomiting.

If you’re still experiencing nausea after three months, talk with your healthcare provider about changing your prescription.

Remember if you stop taking the pill because it’s making you feel sick, you will be at risk of getting pregnant. You’ll need to use another birth control method if you have intercourse.

Combined birth control pills very slightly increase the risk of certain serious health problems including heart attacks, strokes, or blood clots. The risk gets higher if you’re over 35 or you smoke.

Progestin-only pills have fewer serious side effects than combination birth control pills. Ask your health care provider about switching if you’re getting side effects on combined pills.

Immediately contact your nearest health care provider, if you:

Get a new lump in your breast
See a bright flashing zigzag light (an aura) before getting a very bad headache
Have a sudden very bad headache
Have different or more headaches than usual
Get sore, achy legs
Notice your skin or eyes are turning yellow
Have no period after having a period every month

How do I get birth control pills?

First, go to your nearest health care provider for a prescription. They’ll first ask you about your medical history and check your blood pressure. After ruling out any serious conditions, they’ll give you a prescription.

The cost of the pills depends on where you live.

Do birth control pills have any health benefits?

Both combined and progestin-only birth control pills can:

COCs make your periods more regular and lighter
Reduce your menstrual cramps
Give some protection against pelvic inflammatory disease, which if left untreated can make you infertile

The combined birth control pill can also: