First the Facts

• There are three different ways to take combined hormonal contraception (CHC):
  • A pill
  • A patch
  • A vaginal ring
• It prevents pregnancy by stopping ovulation (the release of an egg)
• It is over 99% effective if taken correctly
• Not everyone can use CHC due to certain medical conditions or risk factors
• This type of contraception does not protect against sexually transmitted infections

How Does It Work?

• CHC contains two hormones: oestrogen and progestogen
• Oestrogen and progestogen are released into the bloodstream, preventing your brain releasing hormones that usually trigger ovulation
• It also thickens your cervical mucus making sperm penetration more difficult, and thins the lining of the womb, making implantation of a fertilised egg less likely
• The combined contraceptive pill is different to the progestogen only pill (‘mini pill’) as it also contains oestrogen (two hormones, rather than one)
• It is less effective when not taken correctly

How Do I Take It?

The Combined Contraceptive Pill

• A pill that contains the hormones oestrogen and progesterone.
• There are various regimens that are all effective, and how you take the pill depends on personal preference.

21 days of pill taking followed by a 7-day break (or you can take a shorter break):

• The ‘traditional’ way of taking the pill
• Withdrawal bleed during the break, also known as the hormone-free interval (HFI), where no pills containing hormones are taken
• Re-start the pill on day 8 even if still bleeding
• You may wish to shorten the pill-free week/HFI to 4 days, which can be beneficial to those who experience troublesome symptoms (e.g. headache, mood disturbance) on pill/hormone-free days

Taking a pill every day with no break:

• Also known as ‘extended use’
• You may have ‘breakthrough bleeding’ and if you prefer, you can take a 4- or 7-day break at this time to allow a withdrawal bleed before re-starting (this is called ‘flexible extended use’). This should only be used once 21 pills have been taken

Taking a pill every day for 90 days, followed by a 4- or 7-day break:

• ‘Tricycling’
• You will likely have a withdrawal bleed during the break
• Regimens different to the ‘traditional’ method can have the advantage of reducing the number of withdrawal bleeds overall
• In addition, some women get headaches, mood disturbance on pill/hormone-free days, so reducing the number of days without taking a pill can help these symptoms
• Theoretically, extended regimens can reduce the risk of pregnancy, as pill taking around the pill-free week is the most important. Extended regimens reduce the risk of a missed pill.

The Contraceptive Patch

• A patch containing the hormones oestrogen and progesterone
• The patch is replaced once per week
• It’s a little bit like ‘the pill through the skin’
• You can take a seven-day break after three weeks of patch use, or continue using one patch per week omitting or reducing the patch-free week as with the combined pill
• You can use this method to suit your preferences as described above in ‘the combined contraceptive pill’ section.
• The patch reduces the frequency of having to remember to do something to a minimum of weekly rather than daily

The Contraceptive Vaginal Ring

• A plastic ring containing the hormones progesterone and oestrogen that is inserted into the vagina
• The vaginal ring is replaced once per month
• Remove the ring after 3 weeks of use and have a ring/hormone-free week followed by insertion of a new ring
• Alternatively, you can keep the vaginal ring in for 4 weeks and replace it on day 29 of use.
• You can use this method to suit your preferences as described above in ‘The Combined Contraceptive Pill’ section

What If I Don’t Take Combined Contraception Correctly?

• Contraception is only effective if taken correctly
• If you have not correctly taken your contraception for more than 48 hours (e.g. missed pills, not having your patch on or your ring in your vagina), then you are at risk of pregnancy
• You should resume using your contraception and use extra precautions for 7 days (condoms or no sex)
• If your break is due to start in 7 days, you should omit this and continue with the pill, patch or ring
• If you have had condomless sex around this time you should speak to your local doctor, clinic or pharmacy to discuss whether you need to take emergency contraception

Does It Work Straight Away?

Combined contraception does not always work straight away; it depends when it is started:

• If started within the first 5 days of your period, it will work straight away
• If started after day 5 of your period, you must use another contraceptive (e.g. condoms) for 7 days. This is because it will take 7 days for the CHC method to start working
• It works straight away if commenced within 5 days of miscarriage or abortion. If it is commenced after this, you must use condoms for 7 days
• You should not use any CHC directly after childbirth due to the increased risk of blood clots (at least 3 weeks after if not breast-/chestfeeding, and 6 weeks if you are breast-/chestfeeding)

Are There Any Side Effects?

• Side effects (e.g. mood disturbance, breast tenderness, headaches, nausea) may settle after the first few months of use, and if not, you may wish to try an alternative, e.g., you may experience less side effects with a different combined pill
• CHC usually reduces heavy bleeding. However, some people may experience frequent or irregular bleeding whilst using it. Overall, periods are usually less heavy and less painful while using CHC
• Future fertility is not affected by CHC. Fertility returns almost immediately after stopping it
• There is no evidence that CHC causes weight gain

Special Considerations

• Vomiting and severe diarrhoea can affect absorption of your pill, and additional precautions should be used whilst you are experiencing symptoms and for 7 days after recovery
• Enzyme-inducing drugs can affect metabolism of your pill, patch or vaginal ring. This can reduce how effective the method is, and you should check with a doctor, nurse or pharmacist if you are prescribed any new medication
• Some herbal remedies can also increase metabolism and increase the failure rate of your contraception

Where Can I Get Combined Hormonal Contraception?

You can get it from:

• A sexual health, genitourinary medicine or contraception clinic
• Young person’s clinic
• GP surgeries
• You may be able to get repeat prescriptions online

Is Combined Hormonal Contraception Right for Me?

CHC is not suitable for everyone. Before starting this type of contraception your doctor or nurse will ask you about your personal and family medical history, as well as information about medications you may be taking. If you can take CHC, then this can be continued until 50 years of age, and then you should switch to an alternative method.

You should avoid CHC if:

• You smoke and are 35 years old or over
• You are 35 years old or over and stopped smoking less than a year ago
• You are very obese (body mass index ≥ 35 kg/m²)
• You gave birth less than 3 weeks ago and you are not breast-/chestfeeding
• You gave birth less than 6 weeks ago and you are breast-/chestfeeding

Some medical conditions may mean that CHC is less suitable, for example:

• Current or previous venous thrombosis (deep vein thrombosis (DVT) or pulmonary embolism (PE))
• Heart disease or stroke
• Systemic lupus erythematosus with positive antiphospholipid antibodies
• A heart abnormality or circulatory disease, including hypertension (raised blood pressure)
• Migraine with aura
• Current or past breast cancer or you have a gene that is associated with breast cancer (BRCA1 / BRCA2)
• Active liver or gall bladder disease
• Diabetes with complications
• You are immobile for a long period of time
• You are at an altitude of more than 4,500 metres for more than a week

There are risks and benefits of using CHC:

Written by Dr Nikki Kersey and Dr Paula Briggs
Reviewed and edited by Dr David Rook
Last updated: June 2025 by Dr David Rook