What is a contraceptive implant?

A contraceptive implant is a type of contraception (birth control). It’s a small, thin, flexible rod that’s inserted under the skin on the inside of your arm.

The implant is 4 cm long and made of plastic. It continuously releases small amounts of a hormone, etonogestrel, that prevents pregnancy. Etonogestrel is a progestogen hormone.

There is only one brand of contraceptive implant available in Australia, called Implanon NXT. You can feel the implant under your skin, but you usually can’t see it.

The contraceptive implant is a type of long-acting reversible contraceptive (LARC).

How does the contraceptive implant work?

The hormone in a contraceptive implant is slowly released into your body over 3 years.

It prevents pregnancy by:

• thickening the mucus at the entrance to your uterus (womb) so sperm can't get through
• preventing ovulation (eggs being released from your ovaries)

How is a contraceptive implant put in?

You need a prescription for the implant, and it needs to be inserted by a trained doctor or nurse. The procedure is done using a local anaesthetic to numb your skin, so you don’t feel any pain.

You may need to keep using another type of contraception for 7 days after the implant is put in.

The implant must also be removed by doctor or nurse who is trained in using contraceptive implants. The implant is taken out using a local anaesthetic. A new implant can be put in at the same time.

How well does the contraceptive implant work to prevent pregnancy?

The contraceptive implant works very well — less than 1 in 100 people using the implant get pregnant.

Certain medicines can reduce the effectiveness of the implant. Make sure your doctor knows about all the medicines you use.

Are there any side effects?

You may have some side effects where the implant is inserted or other general side effects.

Side effects at the site of the implant

You may have some bruising or soreness in your arm after having the implant (Implanon NXT) put in or taken out. It may also be a little itchy for a few days, but you should try not to scratch or rub the skin.

You may have a small scar at the implant site.

See your doctor if you can’t feel your implant at any time after it has been inserted. In the meantime, use back-up contraception.

Periods

Contraceptive implants cause changes to your periods. Most women find they have lighter periods than before, and some find their periods stop altogether. Others have:

• irregular periods or vaginal bleeding
• more frequent periods
• longer-lasting periods

These changes may settle after a few months. See your doctor if you have long-lasting or heavy bleeding that continues.

Other side effects

Other possible side effects may include:

• headaches
• acne
• changes in mood
• weight gain
• breast tenderness
• loss of libido (interest in sex)

What are the advantages and disadvantages of the contraceptive implant?

Advantages of the implant:

• It’s very effective at preventing pregnancy.
• It lasts for 3 years, but can be removed earlier.
• It doesn’t interfere with having sex.
• There’s no need to remember to take a pill or have injections.
• It’s not expensive.
• It can be used after having a baby and when breastfeeding.
• It might make your periods less painful and lighter, or they may stop altogether.
• It may improve acne.
• Periods usually return within one month of removing the implant.

Disadvantages of the contraceptive implant:

• It might change the pattern of your periods or cause vaginal bleeding, especially in the first 3 months.
• It can cause slight bruising and pain when inserted or removed.
• It might move from its original position.
• It may leave a small scar and cause other side effects.
• A contraceptive implant won’t protect you from sexually transmitted infections (STIs).

Who is the contraceptive implant not suitable for?

Contraceptive implants are not suitable for people who have breast cancer. It also should not be used if you are pregnant or think you might be pregnant.

The implant may also not be recommended if you:

• have had breast cancer in the past
• have severe liver disease
• have unusual vaginal bleeding
• develop certain heart problems, stroke or mini-strokes during its use
• take certain medicines

Resources and support

Family Planning Australia has a full range of fact sheets on contraception.

The Royal Women’s Hospital has information about long-acting reversible contraception (LARC), including contraceptive implants, in English, Arabic, Chinese, Hindi, Spanish, Urdu and Vietnamese.

You should talk to your health professional about the benefits and risks of getting a medical implant. Use the Therapeutic Goods Administration's guide on what to ask. The information is in English, Arabic, Croatian, Farsi, Greek, Italian, Korean, Mandarin, Spanish, Turkish and Vietnamese.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.