A thin, plastic rod, the length of a matchstick, secured under the skin of a woman's upper arm. It lasts for three years and is 99% effective. The most commonly-used implant is Nexplanon so you may hear it referred to as that.
The implant releases a constant and even dose of the hormone progestin into the bloodstream. This stops the ovaries from making eggs and thickens the mucus in the cervix, forming a plug in the neck of the womb, which makes it harder for sperm to pass through and fertilise an egg. The womb also becomes thinner, which means if an egg were to fertilise, it couldn't attach itself to the womb.
Convenience. It lasts for up to three years, so unless you remove it, you don't have to think about contraception during that time. It's good for women who can't use the hormone oestrogen, which is found in the pill, contraceptive patch and vaginal ring and it can be fitted any time during the monthly cycle. It's 99% effective, doesn't affect fertility or cause weight gain and evidence shows it can help reduce heavy periods and menstrual pain.
It can cause side effects such as headache, nausea, acne, breast pain and mood swings. It may also affect periods, making them irregular or stopping them altogether. It doesn't protect against sexually transmitted infections (STIs) so to have safe sex, you will still need to use condoms.
Most women, including those who have just giving birth, are breastfeeding or have had a miscarriage or termination. The implant may not work for women who have or have had cervical or breast cancer, a stroke, heart attack, have a chronic health condition or take medications for HIV, epilepsy or tuberculosis (TB), so seek medical advice first.
Last updated April 20, 2018