What Are Contraceptive Injections? How Do They Work? Advantages And Disadvantages

A contraceptive injection contains depot medroxyprogesterone acetate (DMPA), a hormone similar to progesterone, which is naturally produced in the body by the ovaries.

What Are Contraceptive Injections?

As well as being known as Depo or Depo-Provera, contraceptive injections are also known as Depo. After entering the body, these depots release progesterone hormone into the veins. It has been said that if these injections are administered correctly at the right time, they have a 99 per cent likelihood of success [1].

A contraceptive injection is also composed of progesterone, estrogen hormones, or just progesterone hormones, just like birth control pills. These hormones enter the body, prevent egg production, and thicken the mucus in the cervix, thereby preventing egg formation and fertilisation [2].

What Is The Use Of Contraceptive Injections?

For women who do not want to take pregnancy pills daily, contraceptive injections are the best option. Typically, the effect of these injections lasts 8 to 13 weeks after administration. However, if the injection is administered for three months, you do not have to take the pill every day, nor do you have to remember to take it according to the prescribed date [3].

What Are The Types Of Contraceptive Injections?

There are two main types of injectable contraceptives [4]:

1) Progestogen-only Injectables (POI) containing only synthetic progesterone.

The medication comes in two types: a) Depot MedroxyProgesterone Acetate (DMPA) - three monthly injections. b) Norethisteroneenanthate (NET-EN) - two monthly injections.

2. A combined injectable contraceptive (CIC) is a monthly injection of estrogen (usually ethinylestradiol) and progesterone.

Contraceptive injections are classified according to their duration. For example, a monthly injection lasts for one month. Secondly, there is an injection that is effective for two months. Finally, there is a third injection that is effective for three months, the most popular injection.

How Do Contraceptive Injections Work?

By thickening the cervical mucus, the injections make it more difficult for sperm to move through the cervix, and thinning the womb's lining decreases the likelihood that a fertilised egg will implant successfully.

Usually, Depo-Provera and Noristerat (brands of contraceptive injections) are injected in the lower arm. Still, they can also be injected into the upper arm [5].

Sayana Press (brands of contraceptive injections) injections can be administered in the tummy (abdomen) or thigh, and you would typically be able to administer them on your own.

As long as you are not pregnant, you may have the injection at any time during your menstrual cycle. However, the injection during the first five days of your menstrual cycle will immediately protect you from becoming pregnant.

You will need to use additional contraception, such as condoms, for seven days after receiving the injection if you receive the injection on any other day of your cycle.

What Are The Benefits And Side Effects Of Contraceptive Injections?

The benefits of contraceptive injections are as follows:

• The duration of each injection is either eight weeks or 13 weeks.
• Sexual activity is not interrupted by it.
• If you cannot use oestrogen-based contraception, this is an option.
• There is no need to remember to take a pill every day.
• While breastfeeding, it is safe to use [6].
• It does not interact with other medications.
• Some women may benefit from it because it reduces heavy, painful periods and relieves premenstrual symptoms.

The side effects of contraceptive injections are as follows:

• After stopping the injections, you may experience irregular periods, heavier periods, shorter periods, or no periods - this may continue for several months after you stop the injections.
• There is no protection against STIs provided by it [7].
• Until your periods return to normal and you become pregnant, there may be a delay of up to one year.
• Depo-Provera and Sayana Press contraceptive injections may cause some individuals to gain weight.
• Side effects may include headaches, acne, hair loss, decreased sex drive, and mood swings.

Any side effects may persist as long as the injection lasts (8 or 13 weeks) and for some time afterwards [8].

On A Final Note...

A contraceptive injection is a hormone injection that prevents pregnancy. It works for 12 weeks. The injection contains depot medroxyprogesterone acetate (DMPA), similar to progesterone. Currently, contraceptive injections are not available in India.