Contraceptive: what is it for and how does each type work?

The contraceptive is mainly used to prevent pregnancy. In addition to inhibiting conception, these drugs are also used to treat various syndromes and diseases in the female reproductive system, such as endometriosis and polycystic ovary syndrome.

Understand what the contraceptive is for and the differences between each type in the following text:


How does contraceptive work in the body?

Birth control pills have two different ways of acting in the body. One of them affecting sperm with the modification of cervical mucus (secretion produced by the cervix), the other function is to reduce and prevent ovulation. Such actions depend on the type of pill and the brand.

How does the birth control pill work?

Birth control pills are combinations of hormones that act in the body to prevent pregnancy. If taken correctly, the contraceptive pills guarantee an efficiency of around 96% against an unwanted pregnancy, this during all days of the month.

But, it is important to note that, during the first pack , the pills may not be having an effect.

Therefore, it is recommended that in this initial month, the prevention of pregnancy is done with two contraceptive methods, that is, with the pill and another form of prevention (such as condoms).

If you forget to take a dose, you should take that tablet as soon as you remember, even if you need to take two pills together.

If more than one dose is missed during the same pack, the drug’s effectiveness may be reduced.

If in doubt, read the package leaflet or see a gynecologist.

There are two types of birth control pills: cartons that have 28 doses and those that have 21 doses. One tablet should be taken daily. Understand better:

Carton with 28 doses

The pack with 28 doses should be taken for 28 consecutive days, without interruption and preferably at the same time.

It is recommended that you start the pack on the first day of menstruation. When finishing a card, start another one without any pause between them.

When taking this pill, it is not common to have bleeding from the exhaust. But it can happen eventually. If it is recurrent, it is advisable to look for a gynecologist who can prescribe another contraceptive medication.

Carton with 21 doses

The pack with 21 doses should be taken for 21 consecutive days, without interruption. After these three weeks, you should take a 7-day break before starting a new pack.

Escape bleeding can happen during that week when you are not taking the pill. But, the period that this bleeding will occur varies for each woman.

It is recommended that you start the pack on the first day of menstruation.

After 28 days (21 taking the pill and 7 without taking it) start a new pack, regardless of whether or not menstruation comes.

For example, if your period started on the first day, start taking the pill that same day. On the 21st, it will be the last dose. Between the 22nd and 27th the tablet should not be taken. Start a new card on the 28th of that month (8th day).

Read more: Morning after pill: how it works, how to take it, names and price   

When to choose contraceptive injection?

The contraceptive injection contains hormones that prevent ovulation and, consequently, pregnancy. This injection, applied to the gluteal region, must be administered by a health professional. Therefore, if in doubt, consult your doctor or pharmacist.

If the goal is to avoid a pregnancy, the contraceptive injection is more effective than the pills, because it needs to be taken only once and there is no risk of forgetting the doses.

However, the contraceptive injection has some negative aspects. Once taken, the drug’s effect cannot be stopped during its action on the body.

In addition, it is common for women to have their menstrual cycles unregulated during or after this treatment.

This injection is not recommended for all women. Therefore, before taking it, it is advisable to seek a gynecologist, who can prescribe the best contraceptive treatment.

This injection can be monthly and quarterly:


The injection should be given, preferably, on the first day of menstruation. However, there is a tolerance of up to 5 days after the start of menstruation. The next injections should be given every 30 days;


The injection should be given up to one week after the start of menstruation. The next dose will be taken between 90 and 95 days.

What is the contraceptive patch for?

The contraceptive patch prevents pregnancy by releasing hormones like estrogen and progesterone . Because it is glued to the skin, hormones are constantly released into the bloodstream. This prevents the woman from ovulating, ensuring the effectiveness of this method.

The method can be applied to the upper arms, the abdomen, the buttocks and the back. Because it is beige in color and looks like a plaster, the adhesive tends to be discreet, but can be seen depending on the type of clothing you are wearing.

The contraceptive must remain in the same place for a week , until it is replaced by another that can be applied in the same place or in different parts of the body.

This method should be done in the same way as the pill pack with 21 doses, that is, the woman should use the patches for 3 consecutive weeks and stay the next week without using it. During that week without the patch, menstruation may go down.