Already prescribed Nexplanon?

Having decided that the contraceptive implant fits your current lifestyle and a doctor has checked that you can use it, the following patient information will tell you more about the implant, what to expect when it is inserted and how your periods may change during its use.

*The Nexplanon diary card is a small information booklet about the implant including a diary card that you can use to keep a record of your bleeding pattern once you've had the implant inserted.

Tell me more about the implant

Things you should know about the contraceptive implant:

  • What is it?

    It is a long-acting, reversible contraceptive in the form of a small, flexible rod.

  • Where is it inserted?

    It is inserted just under the skin on the inside of the upper arm.

  • How big is the implant?

    It is 40 mm long and 2 mm wide. So, about the same size as a hairgrip or a matchstick.

  • How long does it last?

    Nexplanon can be left in place for up to 3 years.

  • How does it work?

    To become pregnant, sperm has to fertilise the eggs released from your ovaries. Nexplanon releases a small amount of a synthetic hormone (a progestogen called etonogestrel) into your body every day which prevents the monthly release of eggs from your ovaries.

  • Will it fit my lifestyle?

    The implant may be suitable for you if you want a contraceptive without the pressure of remembering to take daily pills, if you don’t feel ready to have a baby, or if you want to forget about contraception for a while before having another baby. You can discuss contraceptive options with your doctor or nurse to determine whether the implant is right for your lifestyle. In addition, you can explore different options on, a website produced by MSD.

  • How reliable is Nexplanon?

    No method of contraception is 100% effective. However, Nexplanon is more than 99% effective. This means that in any given year, less than one in every 100 women who use it will get pregnant.

  • How quickly will it start to work?

    Nexplanon starts working immediately provided it is inserted and used as recommended.

  • What side effects could occur?

    As with most medicines, there is a possibility of some side effects with Nexplanon. The most common ones reported are: irregular bleeding, acne, headaches, breast tenderness and pain, weight changes and vaginal infection. However, these don't occur in everyone.

    Check the patient information leaflet you were given for more information and always discuss any concerns you might have with your doctor or family planning nurse.

  • How will I know when it’s time to remove it?

    Nexplanon must be removed after 3 years, and sooner in someone of above average weight. When the implant was inserted you should have been given a user card that states the latest date by which it should be removed. Please keep the card somewhere safe, and make an appointment to see your doctor well before this date.

What happens during insertion?

If you’ve been prescribed Nexplanon but not yet had the implant inserted by a trained implant fitter, the following summarises the relatively quick and simple procedure.

  • Lie down
    You will be asked to lie on your back with the arm that the contraceptive implant is to be inserted into slightly bent at the elbow and turned outwards.
  • Insertion site cleaned
    The insertion site will be identified and a disinfectant used to clean the area.
  • Local anaesthetic given
    A local anaesthetic will be used to numb the area. The skin covering the insertion site will be stretched slightly to allow a needle to be inserted directly under it.
  • Nexplanon inserted
    The Nexplanon implant will then be inserted and the healthcare professional will check it is in the right position.
  • Feel the implant
    You will be asked to feel the Nexplanon implant, although you should not be able to see it.
  • Sterile dressing applied
    A sterile dressing and a pressure bandage to minimise bruising will be placed over the site of insertion. The pressure bandage can be removed after 24 hours, and the sterile dressing after 3–5 days.
  • User card given
    This notes the implant’s location, date of insertion, and the latest date that it should be removed or replaced. Keep this card in a safe place as it will help when you want to remove or replace your implant.

Will my periods change?

Every woman is different where periods are concerned. Because the contraceptive implant contains a progestogen and no estrogen, you may experience some changes to your normal vaginal bleeding pattern. When you are using Nexplanon, your menstrual bleeding may change and become absent, irregular, infrequent, frequent, prolonged, or rarely heavy.

  • Become lighter or less frequent
  • Stop altogether
  • Become heavier
  • Last longer

All of these changes are common to progestogen-only methods of contraception. The bleeding pattern that you experience during the first three months generally indicates your future bleeding pattern. Painful periods may improve.

Keep a period diary

Keeping a diary can help you monitor how your bleeding pattern changes with the use of the contraceptive implant. Download the Nexplanon Diary Card, which contains an example of a bleeding pattern diary.

Talk about changes

Please consult your doctor or family planning nurse if you are worried about any bleeding pattern changes that may occur while using the contraceptive implant.  

Did you know these facts about using the implant?

*The insertion time will depend on your recent contraceptive history as well as your personal situation e.g postpartum, breastfeeding, abortion, miscarriage...

Sign up for the e-mail reminder service

Nexplanon can remain in place for up to 3 years after which time it should be removed and replaced, or another contraceptive method used.

You will need the user card you that were given when the implant was inserted to sign up for this free e-mail reminder service.

If you do not have the user card, please consult the healthcare professional or practice where the implant was inserted.

Before signing up to this service, speak with your healthcare professional about the planned date for removal.

Anytime After Nine Ltd maintains the e-mail reminder service independently of MSD and will not share your information with anyone.

Reporting side effects: If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in the package leaflet. You can also report side effects directly via the Yellow Card Scheme at By reporting side effects you can help provide more information on the safety of this medicine.