Contraceptive pregnancy worries

Questions raised over three-year implant, Implanon, after 500 pregnancies


If you’re happy with the size of your family right now and are currently using a contraceptive or thinking about using one, read on.


The effectiveness of a particular contraceptive implant called Implanon has been called into question after it was revealed that more than 500 women who were using the implant have become pregnant.

However, the Department of Health has advised that there is no need for immediate alarm among users of Implanon, but if you are worried, talk to your GP about your options.

What is important to remember is that no form of contraception is 100% effective, even if you use it according to instructions.

Contraceptive implants, which have grown in popularity over the past five years, work by slowly releasing hormones over a number of years into your blood stream. These hormones affect your menstrual cycle in a similar way to the contraceptive Pill.

The implant is inserted under the skin in your upper arm and can stay there for up to three years, after which time it stops working and needs to be removed. It can also be removed before this time if you no longer want contraception or it causes side effects.

Implanon is said to be over 99% effective, and so statistically you’d expect one woman in every 1000 to become pregnant while using it over a three year period.

In comparison the contraceptive Pill claims to be around 99.8% effective and so also carries a small risk of pregnancy. The Mini Pill carries more risk, with an effectiveness of around 97.2%.

It’s thought that the Implanon pregnancies may have been due to incorrect insertion of the implant rather than it not working properly. Indeed, the NHS has received over 1000 complaints about Implanon, the majority of which have come from doctors and nurses, who have found the device difficult to insert and impossible to check afterwards.

The manufacturer, MSD, has now produced an alternative contraceptive implant called Nexplanon, designed to reduce the risk of errors when inserting the implant. Nexplanon can also be checked after implanation using X-rays or CT scans.


If you are concerned about Implanon speak to your doctor or call the FPA helpline on 0845 122 8690 (9am-6pm Mon to Fri in England) or 0845 122 8687 (9am-5pm Mon to Fri in Northern Ireland), but don’t try to remove it yourself.


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