What is the contraceptive implant?
The contraceptive implant is a small, flexible plastic rod (about the size of a matchstick) that’s inserted under the skin of your upper arm. It slowly releases a hormone called progestogen to prevent pregnancy.
In the UK, the most commonly used implant is Nexplanon
How does it work?
The implant prevents pregnancy by:
- Stopping ovulation (no egg is released)
- Thickening cervical mucus, making it harder for sperm to reach the egg
- Thinning the womb lining, making it less likely for a fertilised egg to implant
How effective is it?
Over 99% effective
That means less than 1 in 1000 people will get pregnant while using it.
How long does it last?
- Up to 3 years
- You can have it removed at any time
- Fertility returns quickly after removal
What’s the fitting like?
- Inserted in a quick procedure by a trained nurse or doctor
- Local anaesthetic is used – it’s painless after numbing
- The implant sits just under the skin of your non-dominant upper arm
- A small bandage is placed over the site
- You may have some bruising or soreness for a few days
What are the benefits?
- Highly effective and long-lasting
- No daily pill to remember
- Can help make periods lighter or stop altogether
- Reversible – fertility returns as soon as it’s removed
- Safe to use while breastfeeding
- Suitable if you can’t use oestrogen
Are there any side effects?
Common (especially in the first 6 months):
- Changes to periods – may become irregular, lighter, heavier, or stop completely
- Spotting between periods
- Mood changes
- Headaches
- Breast tenderness
- Skin changes (e.g. acne)
These usually improve with time. If bothersome, speak to your doctor – removal is always an option.
Risks (rare):
- Minor bruising or infection at the insertion site
- The implant may move slightly (very rarely makes removal difficult)
- A small number of people may not tolerate the hormone well
Who is it suitable for?
It’s ideal for people who:
- Want long-term contraception without daily effort
- Prefer a non-oestrogen method
- Are breastfeeding
- Have heavy or painful periods or endometriosis
Not suitable if you:
- Have liver disease
- Have certain types of cancer (like breast cancer)
- Have unexplained vaginal bleeding (needs checking first)
After care and checks:
- You’ll be able to feel the implant under your skin
- No ongoing appointments needed unless there’s an issue
- Make a note of the removal date (in 3 years)
- Removal is quick and done in the same way as insertion
Does it protect against STIs?
No – the implant does not protect against sexually transmitted infections.
Use condoms for protection against STIs.
When to see a doctor:
- You can’t feel the implant
- It feels like it’s changed position
- You have side effects you’re struggling with
- You want to remove or replace it
- It’s approaching the 3-year expiry