Contraceptive injection: advantages, disadvantages and FAQ

The contraceptive injection is an option for those who have difficulty adapting to the use of the pill, for forgetting to take it at the same time and every day.

It is a method composed of the hormone progesterone or progesterone and estrogen together, with long-term doses. The application can be carried out monthly or quarterly, in the gluteal region.

Although it is considered a practical method, it is not recommended for all women. In order to receive it, first, it is necessary to check the possibility with the gynecologist . Who should give the injection is a health professional.



One of the main attractions, shall we say, is its durability. For 1 to 3 months the woman does not have to worry about this issue on a daily basis. Other characteristics considered positive in contraceptive injection involve the following factors:

  • It does not require daily or weekly control;
  • The 3-month injection is an alternative for women in which the estrogen hormone is contraindicated;
  • It does not interfere with sexual life;
  • Some injections can be used while breastfeeding;
  • In some cases, it also helps to reduce menstrual flow and cramps.

Read more: Contraceptive IUD (mirena, copper): what it is, price, how it works


A negative characteristic of the contraceptive injection is the fact that it is irreversible for a period of 1 or 3 months. Faced with side effects, there is no way to stop its use.

Other not very advantageous points of this method are:

  • Because it is applied by injection, it may not be a good option for those who are afraid of a needle;
  • It can cause headaches and changes in mood;
  • It can cause abdominal discomfort and weight gain;
  • In some women, it causes unregulated menstrual cycles;
  • It does not protect against sexually transmitted diseases;
  • It can cause irritation and pain in the applied area;
  • Although rare, the monthly injection can cause complications such as heart attack, thrombosis and stroke;
  • It needs to be applied by someone in the healthcare field.

Common questions

Clarify some of the main doubts about the use of the contraceptive injection:

Do I need to go to the hospital for the contraceptive injection or can it be applied in pharmacies?

It must be administered by a health professional, but it is not mandatory to go to a hospital for the injection to be given by a doctor. It can be applied by the pharmacist himself, in the purchase of the medicine.

Does injectable contraception affect a woman’s fertility in the long run?

Injections temporarily interfere with a woman’s fertility, but should not make her infertile. However, it may take a little longer to get pregnant after giving up the injections, when compared to the pill.

In some women, it can take up to a year. This time, however, varies for each woman and is not associated with the time of use.

Should the reapplication of the injection be done according to the first day of the menstrual cycle?

No , reapplication does not happen according to the menstrual cycle, but according to the periodicity of the injection itself. If it is a monthly injection, it should be reapplied every 4 weeks, in the case of a quarterly injection, every 12 weeks.

Read more: Menstrual Calendar (table): how to calculate fertile period, apps

Is there a maximum number of injectable contraceptive applications that can be made?

If this is the most suitable method for you, there is no minimum or maximum number of applications. However, some check-ups should be done to check that your health is up to date and that using this method is not posing any risk.

What decides how often the use will be made are factors such as active sex life and whether or not you want a pregnancy.