Combined oral contraceptive pill

What Is The Combined Oral Contraceptive Pill?

Combined Oral Contraceptive Pill

The Combined Oral Contraceptive Pill, usually called simply ‘the Pill’, contains two hormones, oestrogen and progestogen. The main way the Pill works is by stopping a woman’s ovaries from releasing an egg each month, which means that a pregnancy cannot begin.

How Well Does It Work?

With perfect use the Pill is 99.7% effective. This means that if 100 women use it correctly for one year, less than one will become pregnant.

With typical or ‘real life’ use it is less effective (91%) with up to nine women in every hundred becoming pregnant in a year.

Who Can Take The Pill?

Most women can take the Pill.

Providing there are no medical reasons not to take the Pill, women can safely use the Pill up to the age of 50.

Who Can Not Take The Pill?

You should not take it if:

  • you have had a deep venous thrombosis (blood clot in a vein), stroke or heart attack
  • you have a condition which makes you more prone to blood clots
  • you have severe liver problems
  • you have certain types of migraine
  • you are over 35 and smoke.

You also may not be able to take it if:

  • you have had breast cancer
  • you have unusual bleeding from your vagina that has not been diagnosed
  • you are breastfeeding
  • you have high blood pressure, diabetes, high cholesterol, heart disease affecting your heart valves, active liver disease, lupus, a family history of blood clots, are obese or you are on some other medications
  • you have a body mass index (BMI) of 35 or more
  • you are immobile for a period of time, eg after surgery.

If any of these things apply to you, talk it over with your doctor who will help you decide if you should take the Pill.

Please note, this list of reasons why you should not take the Pill is not exhaustive and there may be other reasons why you should not take the Pill. Please ensure you discuss your individual situation with your doctor.

Types of Pills

There are many types of pills. Each woman needs to talk with a doctor, nurse or other healthcare provider to decide which Pill is best for her. With some types, every pill in the packet has the same amount of hormones. With others, the amount changes through the month but they all work in the same way to prevent pregnancy. 

The Pill typically comes in a 28 day pack and depending on the type of pill, it will have between two and seven pills that have no hormones (sugar pills). You will usually have vaginal bleeding during the days when you take the sugar pills. 

Some types of pill are available on the PBS while others are not. Talk to your doctor about the cost of different pill types if this is an issue for you. 

Starting The Pill

We usually advise starting your first pill packet when you have a period. The instructions that come in the packet will tell you exactly how to take it. With some pills you start with a hormone pill on the first day of your period and you are protected from pregnancy straight away.

With other pills you will need to use some other contraception like condoms, as well as the Pill, until you have taken seven of the hormone pills in your packet. Be sure to ask your doctor, nurse or other healthcare provider exactly when you will be covered by the Pill you have been prescribed.

You may want to keep on using condoms with the Pill because they help to protect you from sexually transmissible infections (STIs)

If You Miss A Pill

If you are LESS than 24 hours late taking a pill (ie. it is NOT more than 48 hours since you took your last pill), take it as soon as you remember, and then take the next one at the usual time. You will still be protected against pregnancy. 

If you are MORE than 24 hours late (ie. it is MORE than 48 hours since you took your last pill), or have missed MORE than one pill, take a pill when you remember, and the next pill at the usual time. Then keep on taking the pills as usual, but use other contraception (such as condoms) as well, for the next seven days. 

IF YOU HAVE LESS THAN SEVEN HORMONE PILLS LEFT IN YOUR PACK, continue to take the remaining hormone pills in the pack as soon as you remember, but do not have the break or take the sugar pills. Go straight on to the active hormone pills in the next pack. You should still use other contraception as well (such as condoms), or don’t have vaginal sex, for seven days after the missed pills.

If you are on a pill that has different types of hormone pills in the packet, doing this can cause unexpected bleeding. Ask your doctor, nurse or other healthcare provider for advice on how to stay safe from pregnancy without getting this unexpected bleeding. 

IF YOU MISS MORE THAN ONE PILL IN THE FIRST SEVEN DAYS OF A NEW PACK OF PILLS, OR START A NEW PACK MORE THAN 24 HOURS LATE and you have had sex in the hormone pill break, or have sex in the seven days after the pills are missed, you should consider using the Emergency Contraceptive Pill (ECP). The ECP is available from pharmacies without a prescription. You will need to use other contraception such as condoms for the next seven days, as well as continuing with the Pill. 

If you are taking the Pill ‘Qlaira’® then different instructions apply for missed pills. You should check the information on the packet. 

Talk to your doctor, nurse or other healthcare provider or ring the Family Planning NSW Talkline on 1300 658 886 as soon as possible if you are concerned about missed pills. 

When The Pill Might Not Work

If you have vomiting or severe diarrhoea, the Pill might not get into your system properly and you could get pregnant. It is best to follow instructions for missed pills just to be sure.

Some drugs including certain anti-epileptic drugs (and even natural therapies) may stop the Pill from working properly. If you are taking any medications including herbal remedies, ask your doctor, nurse or other healthcare provider about this. Remember to tell your doctor you are using the Pill, as sometimes it can cause problems with other medications.

Are There Any Health Benefits From Using The Pill?

As well as effective contraception, the Pill does have some health benefits. When you are taking the Pill, periods are usually less painful, bleeding is lighter and more regular, and there may be fewer symptoms of premenstrual syndrome (PMS). Acne may also improve if you are on the Pill.

You have less chance of cancer of the ovary, bowel and endometrium (lining of the womb).

Are There Any Side Effects From Using The Pill?

Most women feel fine while they’re on the Pill, but it is common to have some side effects at first. You could have irregular bleeding in between periods, sore breasts and nausea (feeling sick) for the first couple of months. This usually settles down by your third packet of pills. Some women find nausea improves if they take the Pill at night.

Other side effects such as headaches, less desire for sex, and feeling irritable are rare. There is no evidence that the Pill is associated with weight gain. Some of these effects may be due to the Pill, but can also be caused by other things in your life. If you are worried, talk to your doctor, nurse or other healthcare provider. They may suggest you try another type of pill, or you may need to change to a different method of contraception.

In some women, the oestrogen in the Pill causes patchy brown discolouration to appear on the face, especially if you spend a lot of time in the sun. If this happens when you are on the Pill you can try to limit your sun exposure and use sun screen. If this doesn’t help, you could try switching to a progesterone-only method or a non-hormonal method of contraception. The brown discolouration can take months to fade, even if you stop taking the Pill.

Are There Any Health Risks From Using The Pill?

Serious health problems caused by the Pill are rare; the most dangerous is blood clots, usually in the legs or lungs (called thrombosis). Warning signs are severe sudden chest pain, shortness of breath, severe pain or swelling in one leg, sudden blurred vision or loss of sight, or sudden severe headache. If you have any of these symptoms contact your doctor immediately.

If You Plan To Have Surgery

If you know you are going to have surgery, tell your doctor you are on the Pill. You will probably be asked to stop taking it and to use other contraception, such as condoms, for four weeks before you go to hospital for major surgery, unless the surgeon is going to give you an anti-clotting drug.

You should also stop the Pill and use other contraception if you are immobilised for a length of time or have a leg in plaster. Talk to your doctor or Family Planning clinic if you have any questions about this.

Medical Checkups

It is good to have your blood pressure and weight checked when you renew your prescription each year. All sexually active women are advised to have a Cervical Screening Test every 5 years.

If You Miss A Period

You may sometimes miss a period while you are taking the Pill. If you have taken all your pills correctly this is unlikely to mean you are pregnant, but if this is the first time this has happened to you, it is sensible to do a pregnancy test. If the test is negative and you have taken the Pill as directed just keep taking it as usual. If you have any other unusual symptoms see your doctor, nurse or other healthcare provider.

Can You Choose To Skip Your Period?

Some women choose to skip their period by simply not taking the break between the last hormone pill, and the first hormone pill of the new packet (skipping the sugar pills). It is safe to do this. Talk to your doctor, nurse or other healthcare provider, or ring the Family Planning NSW Talkline on 1300 658 886 for more advice on this.

Other Contraceptive Pills

Other pills you may have heard of are the progestogen-only pill (POP, sometimes called the mini pill), or the Emergency Contraceptive Pill (ECP).

The progestogen-only pill is useful for women who cannot take oestrogen, but may cause irregular bleeding and has to be taken within the same three hours every day.

The Emergency Contraceptive Pill is taken after you have had intercourse without using contraception, to try to prevent pregnancy. It is available to buy from a pharmacy without a prescription. Family Planning NSW has fact sheets on both these pills.

Other Methods of Contraception

There are many other methods of contraception available. See FPNSW factsheets.

For More Information

  • Contact the Family Planning NSW Talkline on 1300 658 886 or go to our Talkline page.
  • NRS (for deaf) 133 677
  • Or visit your nearest Family Planning clinic

Find out about the combined oral contraceptive pill including how it works & it's effectiveness, who can use it, the side effects, how to take it; where to get it.

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