An implant is a small rod made of plastic. This rod is inserted under the skin (typically in the upper arm), where it releases hormone.
This article is part of our Contraception Series!
What we're covering
What side-effects could I get?
What happens to my fertility if I stop?
Note: the information below was sourced from references (1-5), unless stated otherwise.
What is it?
An implant is a small rod made of plastic. This rod is inserted under the skin (typically in the upper arm), where it releases hormone. Depending on the type of implant available in your country, the implant releases a type of progestin (explained below) continuously over three to five years. When this period has passed, you have to get it replaced to stay protected. If you’re looking for protection that lasts even longer, an IUD may be more suitable for you.
To prepare you for the insertion of the implant, you’ll usually receive an injection of a local anesthetic (lidocaine). This may be a bit painful. Inserting the implant is very quick: it usually takes about five minutes. You shouldn’t feel this happening if you’ve had the lidocaine injection. Afterwards, a bandage is usually applied, and you will typically experience some tenderness and bruising for a few days.
No physical examinations are usually necessary before insertion of the implant.
How does it work?
The hormone progestin (a synthetic [man-made] version of the natural hormone progesterone) prevents ovulation, thickens the mucus present in the cervix, and makes the endometrium thinner. This combination of effects prevents the release of an egg in the first place, but also prevents sperm from coming into the uterus through the cervix (thereby stopping fertilization of any egg that is released anyway), and makes the conditions in the endometrium less favorable to implantation of a fertilized egg.
How effective is it?
The implant is one of, if not the most effective contraception available. The perfect use and typical use effectiveness is nearly 100%; out of 1000 people* with an implant, only 1 person will become pregnant within a year.
In some people, it’s less effective due to medications they’re taking (for example, medication for seizures or St. John’s wort). Ask your doctor about any interactions with drugs and supplements you take, because this might increase your risk of pregnancy.
What are possible side-effects?
Sometimes, implants can cause irregular light bleeding or spotting from the vagina. Some people stop menstruating completely. Other possible side-effects include headache, worsened or improved acne, weight gain, pain in your abdomen, nausea, and mood changes. Some cases have been reported in which the implant moves around or comes out the skin, but it’s very rare that this leads to dangerous situations (6).
Your risk of endometrial cancer may be reduced.
Note that only a portion of people experience (some of) these side-effects, and some people will experience side-effects not listed here. Whether you will, depends on many different factors.
When can't I use it?
When you’re pregnant, suffer from thrombosis, or have a liver tumor, active severe liver disease, heart disease, certain rheumatic diseases, abnormal genital bleeding that has not been diagnosed yet, or breast cancer.
Sometimes, you can get an implant even if you have one of these things. Talk to your doctor to find out if your health issue would definitely mean you can’t get an implant.
Does it work immediately?
This depends on when your implant was inserted. If you got your implant within five days of starting your menstruation, you’re protected immediately. If you got your implant after more than five days since starting your menstruation, you need to use another method of contraception (for example, a condom) if you’re having sex in the seven days following your implant insertion. You also need to do this if you’re more than three weeks postpartum and aren’t breastfeeding. Check with your doctor which situation applies to you if you’re not sure.
What happens to my fertility if I stop using it?
Fertility typically returns in about a month following removal of your implant (7).
Does it protect against sexually transmitted diseases (STDs)?
No. Hormones alone do not protect against STDs. If you’re having sex with someone new or untested, use a barrier method as well.
*People, here, means anyone who is able to become pregnant, including girls, women, and non-binary people and transgender men who still have their uterus, vagina, and ovaries.
Are you curious about other methods to protect yourself from an unwanted pregnancy? Read about other birth control options here!
This article is pending medical review.
Written by Juliëtte Gossens
Reviewed by Sophie Oppelt and Selina Voßen
Edited by Juliëtte Gossens
McFarlane I (ed.). Seeing the unseen: The case for action in the neglected crisis of unintended pregnancy. United Nations Population Fund. 2022. Available from: https://www.unfpa.org/sites/default/files/pub-pdf/EN_SWP22%20report_0.pdf
Hacker NF, Gambone JC, Hobel CJ (eds.). Hacker & Moore’s Essentials of Obstetrics & Gynecology. 6th ed. Philadelphia: Elsevier; 2016.
Hoffman BL, Schorge JO, Halvorson LM, Hamid CA, Corton MM, Schaffer JI (eds.). William’s Gynecology. 4th ed. New York: McGraw-Hill Education; 2020.
Centers for Disease Control and Prevention. The United States Medical Eligibility Criteria for Contraceptive Use, 2016 (US MEC). Available from: https://www.cdc.gov/reproductivehealth/contraception/mmwr/mec/summary.html
Centers for Disease Control and Prevention. 2016 U.S. Selected Practice Recommendations for Contraceptive Use (U.S. SPR). Available from: https://www.cdc.gov/reproductivehealth/contraception/mmwr/spr/summary.html
Van Schie D, Lagro-Janssen T. Een hormoonimplantaat komt spontaan naar buiten. Medisch Contact. February 2nd, 2022. https://www.medischcontact.nl/kennis-carriere/wat-ziet-u/wat-ziet-u-gezien/een-hormoonimplantaat-komt-spontaan-naar-buiten.htm [Accessed September 21st, 2022]
Girum T, Wasie A. Return of fertility after discontinuation of contraception: a systematic review and meta-analysis. Contraception and Reproductive Medicine. 2018;3:9. DOI: 10.1186/s40834-018-0064-y
Please note: the information we provide to you here is for educational purposes only. If you’re experiencing any discomfort or have any complaints or questions about your health, please contact your doctor or other relevant health professional. We don’t provide medical advice.