Contraceptive pills and injections
Key points about contraceptive pills and injections
- Contraceptive pills and injections use hormones to prevent pregnancy.
- Contraceptive pills are available in 2 types – the combined pill and the progestogen-only pill.
- The contraceptive injection is called Depo Provera.
- These contraceptive options are suitable for most people, but you need to remember to take the pill every day at the same time or the injection every 13 weeks.
- Talk to your doctor or nurse about if this form of contraception is suitable for you.

These contraceptive methods prevent pregnancy using hormones. You have to take them regularly for them to work well, which makes them different from the long-acting reversible contraceptives (LARC) which you can “fit and forget” for several years. Read more about LARCs.
- Contraceptive pills include the combined pill and the progestogen-only pill.
- The injection is called Depo-Provera, or ‘the Depo’. It is given through a needle into your buttock or upper arm muscle.
Contraceptive pills and injections are suitable for most people but not everyone. Depending on the type, they may NOT be suitable if you have medical conditions such as:
- migraines
- high blood pressure, heart conditions or stroke
- blood clots in the past, or high risk of blood clots
- liver disease
- gallstones
- diabetes
- breast cancer.
Some options may also NOT be suitable if:
- you are overweight with a BMI of more than 35
- you are aged over 35 years and you smoke
- you are taking certain medicines, over-the-counter medicines or herbal supplements.
Your doctor or nurse will be able to work out with you which method is safe and suits you best.
Pros | Cons |
---|---|
✔ They don't interfere with having sex. |
✘ You need to remember to take the pill every day at the same time or the injection every 13 weeks. |
There are 2 types of oral contraception available in New Zealand. These are:
- the combined pill, known as ‘the pill’, which contains the hormones oestrogen and progestogen
- the progestogen-only pill, which contains only progestogen.
Combined pill ('the pill')
The combined pill contains the female hormones oestrogen and progestogen. It works by stopping your ovaries from releasing an egg each month. The combined pill makes periods more regular and lighter, so it is also used to treat heavy or painful periods.
Most people can take the combined pill. However, it may not be suitable if you have some medical conditions. Talk to your doctor or nurse to see if it is suitable for you.
The combined pill needs to be taken every day, but many people do forget one from time to time, so in real-life usage it has an average failure rate of 8% compared with a failure rate of 1% if taken every day.
Chance of getting pregnant: 1–8%.
This means that for every 100 people taking the combined pill for 1 year, there would be between 1 and 8 pregnancies.
Read more about the combined pill.
Progestogen-only pill
The progestogen-only pill works by making your cervical mucus thicker and changing the lining of your womb. This makes it less likely that a sperm fertilises an egg and if an egg is fertilised it less likely to bury itself in your womb to grow. Cerazette is a progestogen-only pill which also stops your ovaries releasing an egg each month.
The progestogen-only pill is safer than the combined pill for some people with medical conditions and has no risk of blood clots. However, it may cause irregular bleeding and it has to be taken at exactly the same time each day which some people find difficult. It can be used while you are breastfeeding.
Chance of getting pregnant: 1–8%.
Real-life usage has an average failure rate of 8% compared with a failure rate of 1% if taken at exactly the same time every day. This means that for every 100 people taking the combined pill for 1 year, there would be between 1 and 8 pregnancies.
Read more about the progestogen-only pill.
The common side effects include irregular bleeding, no periods or a change in weight. It may take up to 1 year for your periods and fertility to return after stopping this method.
Chance of getting pregnant: 1–6%.
This means that for every 100 people using the injection for 1 year, there would be between 1 and 6 pregnancies.
Read more about Depo-Provera.
The video series below explains how the combined oral contraceptive pill works and tells you how to use it.
1. Video: Three ways to take The Pill
This video may take a few moments to load.
2. Video: Learn how to continuously use the Norimin contraceptive pill
This video may take a few moments to load.
3. Video: Learn how to continuously use the Ava 30 contraceptive pill
This video may take a few moments to load.
4. Video: Levlen - how to take it
This video may take a few moments to load.
The following links provide further information about hormonal contraception. Be aware that websites from other countries may have information that differs from New Zealand recommendations.
Combined oral contraceptive pill(external link) Sexual Wellbeing Aotearoa, NZ
Progestogen-only contraceptive pill(external link) Sexual Wellbeing Aotearoa, NZ
Depo Provera injection(external link) Sexual Wellbeing Aotearoa, NZ
Combined hormonal contraceptives(external link)(external link) Patient Info, UK
The combined oral contraceptive(external link) Patient Info, UK
Apps
Fertility apps
Women's health apps
References
- NZ Aotearoa’s guidance on contraception(external link)(external link) Ministry of Health, NZ, 2020
- Oral contraceptives – selecting a pill(external link)(external link) BPAC, NZ, 2019
Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.
Reviewed by: Dr Alice Miller, FRNZCGP, Wellington
Last reviewed:
Page last updated: