Implant

The contraceptive implant is a small plastic rod which is about 4cm long and is inserted sub-dermally, typically on the inner aspect of the non-dominant arm of the patient.

The contraceptive implant works by slowly releasing a progestin hormone that suppresses ovulation.

It may also thicken the cervical mucus, making it harder for the man’s sperm to pass into the uterus. It is a simple procedure to insert the implant but it does require training, particularly to avoid inserting the implant too deep and damaging blood vessels or nerves below the skin.

A correctly inserted implant can be felt under the skin.

Depending on the implant, it needs to be replaced every 3-5 years.

It can take up to seven days for the implant to start working.

Common products

• Etonogestrel (single rod implant , also called Implanon or Nexplanon), which lasts 3 years
• Levonorgestrel (double rod implant, also called Sino-Implant II, Zarin, TRUST or Femplant), which lasts 4 years, or separately another double rod implant called Jadelle, which lasts 5 years

The expiry date on implant packaging relates to the last day that the implant can be inserted for it then to last its expected lifespan.

How effective is the contraceptive implant at preventing a pregnancy?

The implant is very effective at preventing a pregnancy, with less than a 1% failure rate per year (5 pregnancies per 10,000 women).

Over the lifespan of any implant the pregnancy rate does not go above 1%.

What are other good things about the implant?

An implant is safe and suitable for most women. Once inserted the woman does not need to think about it until it needs replacing. It works 7 days after it’s been put in and stops working as soon as it is taken out, allowing an almost immediate return to fertility.

The few reasons that an implant may not be suitable for a woman include breastfeeding a child less than 6 weeks old; abnormal vaginal bleeding; the presence of severe liver damage or cirrhosis; a history of or current deep vein thrombosis; or a history of or current breast cancer.

What women say they like about implants

According to the WHO, some women prefer implants because: they do not require the user to do anything once they are inserted; they last a long time; they work well at preventing a pregnancy; and they do not interrupt sex.

Contrary to the IUD, many women also prefer the implant insertion process as it does not require them to bare their intimate areas to a provider.

What aspects of the implant might women not like/ should they be aware of?

An implant can cause side effects.

Common side effects include changes in bleeding pattern (from irregular bleeding to complete absence), headaches, abdominal pain and skin changes (acne worse or better).

The effects of the implant on the menstrual patterns may cause confusion in some women (who believe a lighter/absent period indicates pregnancy or the elimination of their fertility) and this should be carefully explained during the counselling process.

Women should also be aware that the presence of an implant will not affect their ability to work or do manual labour. If the woman’s weight increases to over 80kg while using a levonorgestrel two-rod implant then this may reduce the lifespan of the implant. In such cases the implant should be replaced one year earlier than the intended lifespan.

Removal of an implant is a small surgical procedure. A replacement implant can be inserted at the same time.

Unlike condoms, implants do not protect against sexually transmitted infections.