Advantages:
It’s a very reliable method of birth control.
You never have to think about it. Once inserted it can remain in place for 3-5 years.
   It can be removed any time. Fertility will return quickly.
Disadvantages:
Your periods may become irregular or excessive. There can be spotting. About 20% of the girls stop having periods; for some this is an advantage, others experience it as a disadvantage.
It requires a minor surgery (local anaesthetic) for insertion and removal.
The implants may be slightly visible.
Possible side effects may be weight gain, losing hair, developing headaches or darkening of the skin over the implant.
It does not protect you against STD’s.