Depo-Provera injection contains the active ingredient medroxyprogesterone acetate, which is a synthetic form of the naturally occurring female sex hormone, progesterone.
Depo-Provera injection is as a long-term form of contraception. It is usually given into the muscle of the buttock or upper arm. The injection produces a reservoir of medroxyprogesterone in the muscle, which is then continuously released into the bloodstream over a period of 12 weeks.
The medroxyprogesterone prevents pregnancy in three main ways. Firstly, it prevents eggs from being released from the ovaries (ovulation). It also increases the thickness of the natural mucus at the neck of the womb, making it more difficult for sperm to cross from the vagina into the womb. By preventing sperm entering the womb, successful fertilisation of any eggs that are released is less likely. The hormone also changes the quality of the womb lining (endometrium), making it less receptive for any fertilised eggs to implant into.
The contraceptive effect of the injection lasts for three months. The first injection should be given in the first five days of a normal menstrual cycle (day one is the first day of your period). This will protect you from pregnancy immediately. The injection can also be given at any other time in your cycle if your doctor is sure that you are not pregnant, but you will need to use additional contraception, eg condoms for the first seven days after having the injection. Further injections should be given every 12 weeks to provide continued contraception.
For women who are using this method of contraception after having a baby, the injection should be given within the first five days after the birth if you are not breastfeeding. However, if it is given within this time you should aware that there is an increased risk of heavy and prolonged bleeding. If you are breastfeeding, you should not be given the first injection until at least six weeks after the birth. Again, further injections should be given every 12 weeks to provide continued contraception.
If you have had a miscarriage or abortion at under 24 weeks, you can have this injection immediately after and you will be protected against pregnancy straight away. If you have the injection more than seven days after the miscarriage or abortion, you will need to use extra contraception to prevent pregnancy for the first seven days after having the injection.
The injection can be used on a short-term basis for partners of men having avasectomy (to provide protection until the vasectomy becomes effective), for women who are being immunised against rubella (to prevent pregnancy during the period of activity of the virus) and in women awaiting sterilisation.
It is very important that you discuss the pros and cons of this form of contraception with your doctor before you are given the injection, particularly with regards to having children after stopping the injections. Fertility does return once the injections are stopped, but the time varies from one women to the next. Most women should start to ovulate 5 to 6 months after their last injection, but may not conceive until 10 to 15 months after their last injection (or sometimes even longer). You should also be made aware of the potential side effects, as the injection cannot be reversed once it has been given.
It is used for contraception.
Not to be used in
- Known or suspected pregnancy.
- History of hormone dependent cancer, eg breast cancer or cancer of the reproductive organs.
- History of liver cancer.
- Active liver disease.
- Vaginal bleeding of unknown cause.
- Current blood clot in a vein of the leg (deep vein thrombosis) or in the lungs (pulmonary embolism).
- Severe disease of the arteries, eg that has caused a stroke or heart attack.
- High blood pressure (hypertension).
- Women who have had a blood clot in the lung (pulmonary embolism), stroke, or blood clot in the eye (retinal thrombosis) when previously on Depo Provera.
- Severe diabetes with complications affecting the eyes, kidneys or nerves.
- Rare hereditary blood disorders called porphyrias
Pregnancy and Breastfeeding
- This medicine should not be used in pregnancy and your doctor should check that you are not pregnant before giving you the first injection. If you are more than two weeks late for any subsequent injection you will also need to have a pregnancy test. Seek medical advice from your doctor.
- This medicine passes into breast milk, however there are no reported harmful effects on the nursing infant when this contraceptive is used by breastfeeding mothers. If you are breastfeeding, you should not be given your first Depo-Provera injection until at least six weeks after the birth.
- Menstrual changes, eg irregular bleeding or spotting, heavy bleeding, or stopping of menstrual bleeding.
- Weight gain.
- Abdominal pain.
- Weakness or loss of strength (asthenia).
- Difficulty in sleeping (insomnia).
- Leg cramps.
- Hot flushes.
- Excessive fluid retention in the body tissues, resulting in swelling (oedema).
- Hair loss (alopecia).
- Decreased sex drive.
- Inflammation of the lining of the vagina (vaginitis).
- Discharge of white fluid from the vagina (leukorrhoea).
- Breast tenderness or pain.
- Abscess at injection site.