What Should You Know About Combined Oral Contraceptive Pill

June 30, 2021 | Written By: Mohd Syafiq

What Should You Know About Combined Oral Contraceptive Pill

Combined oral contraceptive pill (COCP)

The COCP is a combination of two synthetic hormones, oestrogen and progestogen. They mimic natural hormones. They mimic the natural hormones, oestrogen and progesterone, produced by a woman’s body. It is also known as ‘the pill’.

How does it work?

The COCP works in the same ways as the patch and vaginal ring and prevents pregnancy by:

• Preventing the release of an egg.

• Making the mucus at the entrance of the womb thicker, hence making it more difficult for the sperm to enter.

• Thinning the womb lining, making it harder for the egg to be implanted.

How effective is the COCP?

It is over 99% effective if taken correctly and according to instructions.

How do I start taking the COCP?

If you are starting on your first pack of the COCP, it is best to take the first pill on the first day of your period. If you start taking it on any other day, you need to add on another contraceptive method such as condoms for the first 7 days of pill-taking.

Most 21-day COCPs contain the same amount and type of hormones in all the pills of the same pack

You have to take pills for 21 days

  • Take your pill at around the same time each day. Choose a convenient time to take it, and set an alarm to remind yourself if you find it hard to remember


After that, stop taking the pill for 7 days.

  • During this time, you will usually have some bleeding which will appear like a period. As long as you have been taking the pills correctly and you start the next pack on time, you are still protected from pregnancy during this 7-day pill-free break.

Start the next pack after the 7-day pill-free break, even if you are still bleeding.

 There are also some COCPs that contain varying amounts of hormones in different pills of the same pack. This variation is indicated by different pill colours. For these, the pills need to be taken in the correct order.
Some COCPs contain 28 pills in the pack:
Some of the pills are dummy pills that do not contain any medications. The dummy pills are distinguished from the active pills by a different colour. The pills need to be taken in the correct order. After the last tablet of the pack, start the new pack immediately the next day. There is no break between packs of pills.

What do I do if I forget to take my pill?

Take the missed pill as soon as you remember. If you missed more than one pill, take only one replacement pill (leave any earlier missed pills).

Take your next pill at your usual dosage time, even if this means taking two pills in a day (one replacement pill at the time you remember, and the next one at your usual time).

The leaflet that comes with your pill will advise you on what to do next. If you are still unsure, check with your doctor or pharmacist as soon as you can. This depends on:

• How many hours you are late in taking your pill

• How many pills you missed

• In which part of the cycle the pills were missed

Depending on the factors above, you may not be protected against pregnancy and may have to use another contraceptive method, such as a condom for the next 7 days. You may need the morning-after pill if you missed two or more pills in the first week of the pack, and had unprotected sex in the past 7 days. 

Will I still be protected from pregnancy if I am vomiting or have diarrhoea?

The COCP may not be absorbed properly if you vomit within 2 hours of taking it. Take a replacement pill as soon as you are able to and the subsequent pill at your usual dosage time. If vomiting continues, follow the advice concerning missing pills.

If you have severe diarrhoea

The leaflet that comes with your COCP will advise you on what to do. If you are still unsure, check with your doctor or pharmacist as soon as you can.

Will it cause any side effects?

Like all other medications, the COCP may result in some side effects including:

• Nausea

• Headaches

• Sore breasts

• Mood swings

However, these side effects usually subside over time. If you are concerned about them, or should the side effects persist, speak to your doctor or pharmacist. They might switch you to a different formulation of the pill. 

Breakthrough bleeding, or bleeding between periods is common when you first start taking the COCP and your body adjusts to it. The incidence of breakthrough bleeding will decrease with time. Talk to your doctor or pharmacist if your breakthrough bleeding continues after 3 months. They may recommend a different formulation of the pill for you. 

Will it make me fat?

It has not been proven that the COCP causes weight gain.

Is it suitable for me?

If there are no medical reasons for you not to take the COCP, and you do not smoke, the COCP can be taken until menopause. The COCP may not be suitable for you if you have certain conditions, or if you have risk factors for venous thromboembolism or arterial disease. Speak to your doctor or pharmacist before starting on COCP or if you:

• Have a body mass index (BMI) of over 35 kg/m2

• Are over 35 years of age and smoke or stopped smoking under a year ago

• Have high blood pressure

• Have or have had a blood clot, or have a parent, child, brother or sister who has had a blood clot before they were 45 years of age. Venous thromboembolism is the medical term for this

• Are unable to walk around or move much due to an operation, accident or disability

• Have or have had a heart attack, stroke or angina

• Have or have had migraines. Especially migraines with aura

• Have or have had breast or liver cancer

• Have or have had diabetes with complications of the kidneys, nerves or eyes 

Important: Inform your doctor or pharmacist of any illness or operations you have had, or have. 

Will other medications affect its effectiveness?

There are certain medications and herbal supplements that may affect the effectiveness of the COCP. These include certain medications for epilepsy, tuberculosis, meningitis and HIV; and a herbal supplement called St John’s wort. If you need to take any of these, your doctor or pharmacist might advise you to use a different method of contraception. If you are given any medications, always let your doctor or pharmacist know that you are taking the COCP.

Is it true that it will increase my risk of getting a blood clot? 

The COCP may cause your blood to clot more easily. However, the risk of getting a blood clot is very small and the benefits of the COCP normally outweigh the risks for most women. Your doctor or pharmacist will check if you have risk factors for developing blood clots before recommending the COCP. Different types of COCPs also carry different risks of causing blood clots – speak to your doctor or pharmacist to find out more.

The following symptoms could be caused by blood clots. Seek urgent medical attention if you develop any of them while on the COCP:

• Unexplained painful swelling in the leg

• Weakness or numbness of the face, arm or leg

• Breathing difficulties

• Chest pain

If you are immobile for a long time (in a wheelchair or your leg is in a cast), it may not be advisable for you to take the COCP. 


Will it increase my risk of getting cancer?

Research shows COCP is associated with a significant reduction in the risk of the womb and ovarian cancer that increases with the duration of COCP use and persists for many years after stopping COCP. The use of COCP is also associated with a reduced risk of colon cancer. 

Some research suggested current use of COCP is associated with a small increased risk of breast and cervical cancer. However, the risk reduces over time after stopping COCP.

Can I use it if I am breastfeeding?

This is not recommended because the COCP might affect breast milk. Alternative contraceptive methods that are suitable for breastfeeding mothers include:

• Progestogen-only pill

• Condoms

• Contraceptive implant

• Contraceptive injection

• Diaphragm

• Natural family planning

• Contraceptive cap

When can I start on the COCP if I have just given birth?

If you are not breastfeeding, you can start on the COCP on the 21st day after delivery. If it is started more than 21 days after delivery, use additional precautions such as condoms for the first 7 days of pill-taking.

When can I start on the COCP if I have just had a miscarriage?

The COCP can be started up to 5 days after a miscarriage. If it is started more than 5 days after a miscarriage, use additional precautions such as as condoms for the first 7 days of pill-taking.

What are the advantages and disadvantages of the COCP?

Advantages: 

Over 99% effective at preventing pregnancy if taken correctly. In addition to contraception:

• It can reduce painful periods, heavy periods and premenstrual syndrome (PMS).

• It may improve acne.

• It may reduce the risk of womb, ovarian and colon cancer

 • It may reduce the risk of developing ovarian cysts.

• It may reduce the risk of pelvic infection.

Disadvantages:

• It may cause temporary side effects at the beginning, such as headaches, nausea, sore breasts and mood swings. Your doctor or pharmacist might advise you to try a different formulation if they do not subside after a few months of pill-taking. 

• It does not protect you against sexually transmitted infections (STIs). A condom is the only contraceptive method that can also protect against STIs.

• It may cause breakthrough bleeding. The incidence of breakthrough bleeding will decrease with time.


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