WHAT IS THE CONTRACEPTIVE INJECTION?
The contraceptive injection is a hormonal contraceptive containing Depot Medroxyprogesterone Acetate (DMPA). DMPA is a progestogen that is similar to the hormone progesterone made by your body. DMPA has been available as a contraceptive method for many years.
HOW IS IT GIVEN AND HOW OFTEN?
The contraceptive injection is given by a doctor or nurse every twelve weeks in the upper arm or buttock.
HOW DOES IT WORK?
The contraceptive injection works by preventing ovulation (an egg being released from the ovary). It also thickens the mucus in the cervix which makes it difficult for sperm to enter the uterus (womb). The DMPA is released slowly into your body over time and each injection protects you from becoming pregnant for twelve weeks.
HOW EFFECTIVE IS THE CONTRACEPTIVE INJECTION?
The contraceptive injection is 96% effective in preventing pregnancy. It is more effective if you have the repeat injection right on time every twelve weeks.
WHAT ARE THE POSSIBLE SIDE EFFECTS?
The most common side effect of the contraceptive injection is a change in your menstrual bleeding. Many people find their bleeding ceases altogether over time. This has no harmful effects and most people using the contraceptive injection find this a positive side effect. Some people will continue to experience light irregular bleeding and a small number may experience heavy bleeding or longer bleeding.
Other possible side effects include:
A small amount of weight gain, headaches, and mild acne may occur in some people. Other people report a change in mood or sexual interest, but there is no evidence that these are caused by the contraceptive injection.
WHAT ARE THE ADVANTAGES?
- It is a highly effective contraceptive
- It is relatively inexpensive
- It only needs to be given every 12 weeks
- Commonly there is lighter or no bleeding.
- It can reduce period pain, heavy periods, and premenstrual symptoms (PMS)
- It can reduce anaemia resulting from heavy periods
- It is suitable if you cannot use oestrogen containing contraceptives
WHAT ARE THE DISADVANTAGES?
- There can be a delay to the return of normal fertility in people who use the contraceptive injection. On average this delay is around eight months following the last injection. For this reason, it is not recommended if you are thinking of becoming pregnant in the near future. The contraceptive injection does not affect fertility in the long term.
- There is evidence that there is a small reduction in the density of the bones while people are using the contraceptive injection.
- This effect is reversed when you stop using it.
- Once the injection has been given it cannot be reversed and the effects will be present for twelve weeks.
- You will need to see a health care provider every twelve weeks for the injection.
WHO CAN USE THE CONTRACEPTIVE INJECTION?
Most people can use the contraceptive injection. It is considered safe to use while breastfeeding.
WHEN IS THE CONTRACEPTIVE INJECTION NOT SUITABLE?
The contraceptive Injection may not be suitable for you if you:
- Have a history of breast cancer
- Have a history of stroke or heart disease, or risk factors for these conditions
- Have unexplained vaginal bleeding that might indicate a serious underlying condition
- Have a history of severe liver disease or liver tumours
- Are considering pregnancy in the near future
HOW DO I START THE CONTRACEPTIVE INJECTION?
To start the contraceptive injection, you will need to see a doctor. They will be able to assess if it is suitable for you. This will also give you an opportunity to discuss this method of contraception and to ask any questions you might have.
The doctor will then work out the right time for you to have the first injection. If you are using another hormonal contraception you may be able to start straight away, If you are not currently using a hormonal method of contraception, the first injection needs to be given within 5 days of the start of your period. This ensures that there is no risk of pregnancy at the time. You will be given a prescription to get the DMPA at a pharmacy then return to have the injection. In some clinics, such as SHFPACT, DMPA is kept in stock on the premises so can be given to you at the time without the need to go to the pharmacy.