Implanon: Pros, Cons & Side Effects Explained

Implanon is a hormonal contraceptive implant into the upper arm, lasting for several years. Implanon works very well for many people, causing no side effects^1–3.

If you are sensitive to hormonal contraception, it might be wiser to try other contraceptive options, as this is a long-term hormonal implant.

It is advisable to carefully consider all of your options before choosing Implanon.

Implanon contains: 68mg etonogestrel (progestin-only)

Pros of Implanon

You don’t have to worry about your birth control for up to three years
If it isn’t working for you, you can always take it out and the effects will go away shortly after
It protects you against unwanted pregnancy and is very effective at this function
You can breastfeed with Implanon in
You can get Implanon in after a miscarriage or abortion

Cons of Implanon

Hormonal birth control always comes with risks, as you are interrupting the natural function of hormones in your body (think bone density, vaginal microbiome, mood)
Hormones in birth control are synthetic, with each variant of hormone, by manufacturer, slightly molecularly different (which is why some brands of birth control work better for some people)
The implant leaves a small scar, and carries a small risk of infection with it, as with all skin breakages
Increased risk of ectopic pregnancy
These hormones affect the way your body metabolises carbohydrates and fats, making diabetes and pre-diabetic states something to be aware of, as well as the way your body stores fat (in a nutshell, it can make you fat)

Side effects of Implanon

Everyone reacts to medication differently, and Implanon is no different, but there are patterns to the impact of this drug on your system.

Carefully monitor how you feel, your skin and weight after Implanon is implanted.

Changes to bleeding cycles are likely to occur, so you may stop getting periods, or may bleed infrequently or sporadically, or conversely bleed more often and more heavily. It is unlikely that you will keep your regular cycle.

Mood changes and heavy, irregular bleeding are the two main reasons for having the Implanon implant removed^4,5.

In all studies, the adverse reactions to Implanon were:

Headache 24.9%
Vaginitis 14.5%
Weight increase 13.7%
Acne 13.5%
Breast pain 12.8%
Abdominal pain 10.9%
Pharyngitis (sore throat) 10.5%
Leukorrhea (vaginal discharge) 9.6%
Influenza-like symptoms 7.6%
Dizziness 7.2%
Dysmenorrhea (period pain) 7.2%
Back pain 6.8%
Emotional lability (instability) 6.5%
Nausea 6.4%
Pain 5.6%
Nervousness 5.6%
Depression 5.5%
Hypersensitivity 5.4%
Insertion site pain 5.2%

When Implanon is a bad idea

If you are sensitive to hormonal birth control, other options might suit you better (IUD, condoms, diaphragm)
Check that you are not pregnant before getting Implanon implanted
If you have a history of thrombosis or related disorders, hormonal birth control may not be the best option
If you have liver-related problems, you can’t have Implanon in, because hormones are excreted via the liver and bowel
If you have abnormal genital bleeding of no known cause
Any history of progestin-sensitive cancers
Allergy to the ingredients
In people with out-of-control high blood pressure
If you are concerned about weight changes, hormonal birth control may not be the best option
If you are very overweight, the implant can stop working as well over time

References

1.
Croxatto HB. A multicentre efficacy and safety study of the single contraceptive implant Implanon. Human Reproduction. Published online April 1, 1999:976-981. doi:10.1093/humrep/14.4.976
2.
Moray KV, Chaurasia H, Sachin O, Joshi B. A systematic review on clinical effectiveness, side-effect profile and meta-analysis on continuation rate of etonogestrel contraceptive implant. Reprod Health. Published online January 6, 2021. doi:10.1186/s12978-020-01054-y
3.
Darney P, Patel A, Rosen K, Shapiro LS, Kaunitz AM. Safety and efficacy of a single-rod etonogestrel implant (Implanon): results from 11 international clinical trials. Fertility and Sterility. Published online May 2009:1646-1653. doi:10.1016/j.fertnstert.2008.02.140
4.
Utaile MM, Debere MK, Nida ET, Boneya DJ, Ergano AT. A qualitative study on reasons for early removal of Implanon among users in Arba Minch town, Gamo Goffa zone, South Ethiopia: a phenomenological approach. BMC Women’s Health. Published online January 2, 2020. doi:10.1186/s12905-019-0876-1
5.
Akilimali PZ, J. H, P. A, K. P. K, J. B. Incidence and determinants of Implanon discontinuation: Findings from a prospective cohort study in three health zones in Kinshasa, DRC. Todd CS, ed. PLoS ONE. Published online May 11, 2020:e0232582. doi:10.1371/journal.pone.0232582