Combined Oral Contraceptive Pill

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The Combined Oral Contraceptive Pill is an oral contraceptive containing hormones. It is taken daily to prevent pregnancy.

What is the Pill?

The Pill contains low doses of 2 hormones – an oestrogen and a progestogen. These are similar to the hormones naturally produced in the female body.

There are many combined pills available. They differ in the type and dose of the 2 hormones they contain.

How does the Pill work?

The Pill works by:

preventing ovulation (egg release from the ovary)
thickening mucus in the cervix so sperm cannot enter the uterus (womb)
changing the lining of the uterus, making it unsuitable for pregnancy

How effective is the Pill?

The Pill is 99% effective when taken correctly. This means that if 100 women take the Pill, 1 woman could become pregnant in a year. It is less effective than this if not taken according to instructions. The typical effectiveness rate in studies of women using the Pill is 92%. This rate reflects the fact that the Pill may not always be taken consistently.

What are the advantages of the Pill as a method of contraception?

very effective method of contraception when taken correctly and consistently
fertility returns soon after stopping
predictable and regular bleeding pattern
can be stopped and started to suit contraceptive needs

What are the disadvantages of the Pill as a method of contraception?

needs to be taken on a daily basis
requires medical review for prescriptions
some types of the Pill are expensive
does not protect against sexually transmitted infections (STIs)

What are the possible health benefits of the Pill?

bleeding may be lighter, shorter and more regular with less discomfort
can be used to manage heavy periods and/or painful periods
can be useful in managing a number of conditions including premenstrual syndrome, endometriosis, recurrent ovarian cysts and polycystic ovarian syndrome
women who have ever used the Pill have a reduced risk of cancer of the ovary and uterus
usually improves acne

What are the possible side effects of taking the Pill?

The Pill has few side effects. Some side effects tend to settle within 2 or 3 months of starting the Pill. During this time some women may experience:

nausea
breast tenderness or enlargement
mood changes
breakthrough bleeding
headaches

Other possible side effects that may occur over time include:

skin changes including acne or chloasma (patchy brown skin discolouration of the face)
missed periods
change in sexual interest
weight gain – however studies show that on average, weight gain is not related to the Pil

If you continue to have problems while on a particular type of Pill, discuss it with your doctor, as there may be a more suitable pill for you or you may decide to change to another method of contraception.

What are the possible serious risks of taking the Pill?

While serious risks are extremely rare in healthy women taking the Pill, it is important to note the following:

Thrombosis
A rare but very serious complication occurring when blood clots form in major blood vessels. It is important to recognise the warning signs and seek immediate medical help if any of the following are experienced:
sudden severe chest pains
severe calf pain or swelling in one leg
sudden severe headache
sudden onset of blurred vision or loss of sight

To reduce the risk of thrombosis in the veins after surgery, women may be advised to stop taking the Pill and use another method of contraception before and after a major operation.

Cancer risk
Some studies have shown a slightly increased risk of breast cancer in women currently taking the Pill. However a more recent study found no increase in breast cancer. It is important to discuss your individual concerns with your doctor. There is also some research that suggests that cancer of the cervix may be slightly more common in women taking the Pill. This should not be a concern if you take part in regular cervical screening by having a Pap smear every 2 years.

Is the Pill suitable for all women?

Most women can safely take the Pill.

Your doctor will review the suitability of the method with you prior to providing a prescription.

In assessing your suitability consideration is given to a number of important factors:

history of clotting disorders or thrombosis
history of stroke or heart attacks
cardiovascular risk factors including smoking, high blood pressure, high cholesterol levels or being overweight
certain types of migraine headaches
liver or gall bladder disease
diabetes
breast cancer
unexplained vaginal bleeding (this should be investigated before using the Pill)

The doctor will also review:

any history in your family of clotting disorders or thrombosis
any medications that may interfere with the Pill working effectively
if you are breastfeeding or if you have recently had a baby

What do I need to know about starting the Pill?

Starting the Pill for the first time requires an assessment by a doctor and a prescription. This assessment enables you to ask any questions you may have and be certain that it is the most suitable method for you.

There are different types of packaging of pills. Australian pill packets contain both hormonal 'active' pills and 'inactive' pills. ‘Inactive’ pills are sometimes called the ‘sugar pills’.

Your health professional will explain starting the Pill with you, based on the particular Pill being prescribed for you, as all packages look different. Key points:

when commencing the first pill packet it is usual to start taking the first pill on the first day of a period
if you start on an 'active' pill on any of the first 5 days of your cycle (day 1 of the cycle is the day your period starts) then you are protected against pregnancy immediately
when starting the first packet of the Pill at any other time in your menstrual cycle, you will be protected from pregnancy only after you have taken 7 hormone 'active' pills

What do I need to know about the ongoing use of the Pill?

The Pill needs to be taken at a regular time every day. It can be useful to link pill taking with other activities that are part of your daily routine.

A monthly bleed occurs during the 'inactive’ pills and many women prefer to have this regular period. However if you do not want to have a monthly bleed you can safely take the hormone pills continuously. See your health professional for more information about this.

To renew your pill prescription you will need to see a doctor at least once a year.

The Pill may not be effective if:

a pill is late or missed
vomiting occurs within 2 to 3 hours of taking a pill
you have severe diarrhoea
medications are taken

Certain medications, including antibiotics, may interfere with the effectiveness of the Pill. Always ask your doctor if you will need to follow the missed pill advice (see back page) if you are prescribed any additional medication.

Generally you cannot rely on the Pill for prevention of pregnancy while on the medication and then for the next 7 days of ‘active’ hormone pills.

Some non-prescribed medications, such as St John’s wort (or hypericum), can also make the Pill less effective. Always check with the pharmacist.

If you are concerned about any of the above situations, check with your doctor or health professional.

What should I do if I am late in taking the Pill or miss a pill?

If you are 24 hours or more late for any pills, consult the missed pill section on the back page of this factsheet. If you aren't certain what to do, seek further advice as soon as possible, particularly if you think you may need Emergency Contraception.

Do I need Emergency Contraception if I have missed a pill?

Emergency Contraception may be required if you miss pills and sexual activity occurs without a condom being used. Emergency Contraception should particularly be considered for pills missed in the first week of ‘active’ pills, ie, the first 7 hormone pills taken after the 7 day break on the ‘inactive’ pills.

Emergency Contraception is most effective when taken within 24 hours, but may be taken up to 120 hours (5 days) after unprotected sexual intercourse. It is available without a prescription from pharmacies, general practitioners (GPs), Sexual Health or Family Planning Queensland (FPQ) clinics. See FPQ's Emergency Contraception factsheet.

What should I do if I am sick?

If you vomit within 2 to 3 hours of taking the Pill it may not be effective. Take another pill as soon as you can. Severe diarrhoea may also interfere with the Pill's effectiveness. Follow the missed pill advice as outlined.

Where is the Pill available?

The Pill is available on prescription and can be obtained from your local GP or FPQ clinic.

TIPS FOR PILL TAKERS

Choose a time of day for pill taking that is easy to remember. Simple reminders can help, such as a mobile phone prompt or keeping the Pill packet somewhere that you will notice throughout the day
If you have any side effects, including irregular bleeding, keep taking the Pill and see your health practitioner.
Stopping the Pill mid packet may cause more bleeding and increase your risk of pregnancy.
Never have more than the 7 day break from the ‘active’ hormone pills.
Don't be late in starting the hormone pills after 7 days of ‘inactive’ pills.

Disclaimer

Family Planning Queensland (FPQ) has taken every care to ensure that the information contained in this publication is accurate and up-to-date at the time of being published. As information and knowledge is constantly changing, readers are strongly advised to confirm that the information complies with present research, legislation and policy guidelines. FPQ accepts no responsibility for difficulties that may arise as a result of an individual acting on theadvice and recommendations it contains.