The COCP contains a low dose of oestrogen and progestogen hormones, similar to those naturally produced by the body. There are many different pills available and it is generally recommended to use the lowest possible dose of hormones. Some hormone combinations can be used for specific problems.
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
There are many combined pills
available. They differ in the type and
dose of the 2 hormones they contain.
How does the Pill work?
It works by:
- preventing ovulation (egg
release from the ovary)
- thickening the mucous in the
cervix to prevent the sperm
entering the uterus (womb)
- thinning the lining in the uterus,
making it unsuitable for
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, but it is
less effective than this if not taken
according to instructions. The typical
effectiveness rate in studies of
women using the Pill is 91%. This
rate reflects the fact that the Pill may
not always be taken consistently.
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
- breast tenderness or
- mood changes
- breakthrough bleeding
Other possible side effects that may
occur over time include:
- Skin changes including acne or
chloasma (brown discoloration
on the face)
- Change is sexual response
- Weight gain: studies suggest
this is not related to the pill
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 is a rare but very
serious complication which occurs
when blood clots form in major blood
vessels. This can occur
spontaneously, after an operation or
accident, on the COCP, during and
Warning signs of a thrombosis 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 or go to your
nearest emergency department
It is important to understand how big
the risk is for you. The information below
shows the risk in women in different
situations, from women who are not
pregnant and not taking the pill (two
women in every 10,000 in one year)
to the highest level of risk, for women
after they have had a baby (200
times more than the lowest level, and
60 times more than the lowest risk
level for a woman on the pill).
For every 10,000 women in one year,
thrombosis occurs in:
- 2 women not using the Pill/ring
and who are not pregnant
- 6-12 women using the vaginal
- 29 women during pregnancy
- 300-400 women soon after
having a baby
For the COCP, the risk of thrombosis
varies with the type of progesterone:
- 5-7 women using 1st
generation pills (the pills that
have been in use for the
longest time – containing
levonorgestrel or norethisterone
- 9-12 women using other pills
If blood clots are a specific concern
for you, visit your doctor who can
assess your particular risk based on
your personal and family health
history, as there are specific blood
disorders that might increase the risk
What are the advantages of the
Pill as a method of
- Very effective method of
contraception when taken every
- Readily accessible by most women
- Fertility returns soon after
stopping the pill
- Control over bleeding so that it
can be predictable
What are the disadvantages of
the Pill as a method of
- Must be taken on a daily basis
- Efficacy depends on the reliability of the woman in taking it as directed
- Needs to see a doctor for review
- The cost of the pill varies with the
- The pill gives no protection
against sexually transmitted infections (STIs)
- Some rare but potentially serious side effects
- Some risks associated with Pill use in a number of health conditions, limiting its safety and ability to be used in these situations
What are the possible health benefits of the Pill?
- Lighter periods
- Less period pains
- Can improve acne
- Useful for gynaecological conditions: premenstrual syndrome, endometriosis, recurrent ovarian cysts
- Can reduce or assist with symptoms of the perimenopause and polycystic ovarian syndrome
- Reduced risk of cancer of the uterus, bowel and ovary
- May decrease the odds of developing bacterial vaginosis (imbalance of natural organisms in the vagina and vulva potentially leading to symptoms)
Can all women take the pill?
Most women can safely take the Pill. Your doctor will review the suitability of the method with you before prescribing the pill. Your doctor will ask about your own and your family history:
- A history of blood clots or current health conditions and inherited conditions that might increase your chance of a blood clot
- Certain types of migraine
- A history of stroke or heart problems or risk factors for a cardiovascular problem: smoking, overweight, high blood pressure, high cholesterol
- Gall bladder or liver disease
- Breast cancer
- Unexplained vaginal bleeding - this must be investigated before starting the pill
- Cervical cancer screening status
- History of polycystic ovarian syndrome
- Medications – prescribed and over-the-counter
- The possibility of current pregnancy and past pregnancies and their outcomes
- Breast feeding
- Plans for future pregnancies
Starting the Pill
After the review by your doctor, you will be able to fill your prescription.
Australian pill packets contain both hormonal 'active' pills and 'inactive' pills. ‘Inactive’ pills are sometimes called the ‘sugar pills’.
Your doctor will explain starting the Pill with you, based on the particular Pill being prescribed for you, as all packages look different. Key points:
- 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
- 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 else should I know about 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 – missing out the ‘sugar’ pills of each pack.
The pill can be stopped for a ‘period’ at any time of your choosing. If you decide to take the pill continuously, without a break, and you start to bleed, then stop the pill for 3 days and then restart the pill.
To renew your pill prescription you will need to see a doctor at least once a year.
The pill may not be effective if:
- Your pill is late
- Vomiting occurs within 2-3 hours of taking the pill
- Severe diarrhea occurs
- Other medications are taken
- Some non-prescribed medications, for example St John’s wort (hypericum), can interfere with the action of the pill
For some medications, you cannot rely on the Pill for prevention of pregnancy while on the medication and then for the next 7-28 days of ‘active’ hormone pills.
Check with your doctor for any of these issues.
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 True clinics.