Depo Provera

Depo-Provera is a contraceptive (birth control) product which is injected every 3 months.

It is the brand name for a depot formulation of medroxyprogesterone acetate manufactured by Pfizer Inc. It is a hormonal birth control method containing the pregnane (17a-hydroxyprogesterone derivative) progestin medroxyprogesterone acetate, without oestrogen, and is administered to women in the form of an intramuscular injection once every 11 to 13 weeks.

Depo-Provera causes the ovaries to stop releasing eggs. It is 99.7% effective in preventing pregnancy.

Benefits
Depo-Provera has several advantages:
* Highly effective at preventing pregnancy;
* Injected every 3 months. The only continuing action is to book subsequent follow-up injections every twelve weeks, and to monitor side effects to insure that they do not require medical attention;
* No oestrogen. No increased risk of deep vein thrombosis (DVT), pulmonary embolism (PE), stroke, or myocardial infarction;
* Culturally acceptable. Some cultures believe injections are especially efficacious. Injections also afford privacy because use is not detectable;
* Miinimal drug interactions (compared to other hormonal contraceptives);
* Decreased risk of endometrial cancer. Depo-Provera reduces the risk of endometrial cancer by 80%. The reduced risk of endometrial cancer in Depo-Provera users is thought to be due to both the direct anti-proliferative effect of progestogen on the endometrium and the indirect reduction of oestrogen levels by suppression of ovarian follicular development;
* Decreased risk of iron deficiency anemia, pelvic inflammatory disease (PID), ectopic pregnancy, and uterine fibroids;
* Decreased symptoms of endometriosis;
* Decreased incidence of primary dysmenorrhea, ovulation pain, and functional ovarian cysts;
* Decreased incidence of seizures in women with epilepsy. Additionally, unlike most other hormonal contraceptives, Depo-Provera's contraceptive effectiveness is not affected by enzyme-inducing antiepileptic drugs;
* Decreased incidence and severity of sickle cell crises in women with sickle-cell disease;

Warnings and precautions:
* Depo Provera can require up to fourteen days to take effect. This means pregnancy can occur within fourteen days of the first Depo injection;
* Takes seven days to take effect if given after the first four days of the period cycle. Effective immediately if given during the first four days of the period cycle;
* Offers no protection against Sexually transmitted diseases (STDs);
* Depo Provera can affect menstrual bleeding. After a year of use, 55% of women experience amenorrhoea; after 2 years, the rate rises to 68%. In the first months of use "irregular or unpredictable bleeding or spotting, or rarely, heavy or continuous bleeding" was reported;
* Delayed return of fertility. The average return to fertility is 9 to 10 months after the last injection. By 18 months after the last injection, fertility is the same as that in former users of other contraceptive methods;
* Long-term studies of users of Depo-Provera have found slight or no increased overall risk of breast cancer. However, the study population did show a slightly increased risk of breast cancer in recent users (Depo use in the last four years) under age 35, similar to that seen with the use of combined oral contraceptive pills.[16];
* Infants born to women exposed to Depo during pregnancy in one study had an 80% greater chance of dying in the first year of life;
* Black box warning: While it has long been known that Depo-Provera causes bone loss, it has recently been discovered that the osteoporotic effects of the injection grow worse the longer Depo-Provera is administered, may remain long after the injections are stopped, and may be irreversible;

Side effects:
In the largest clinical trial of Depo-Provera, the most frequently reported adverse reactions (which may or may not be related to the use of Depo-Provera) were:
* menstrual irregularities (bleeding or amenorrhoea or both);
* abdominal pain or discomfort;
* weight changes;
* headache;
* weakness/fatigue;
* nervousness;

Contraindications:
Conditions where the theoretical or proven risks usually outweigh the advantages of using Depo-Provera:
* Multiple risk factors for arterial cardiovascular disease;
* Current deep vein thrombosis (DVT) or pulmonary embolus (PE);
* Migraine headache with aura while using Depo-Provera;
* Before evaluation of unexplained vaginal bleeding suspected of being a serious condition;
* Past history of breast cancer and no evidence of current disease for 5 years;
* Active liver disease: (acute viral hepatitis, severe decompensated cirrhosis, benign or malignant liver tumours);
* Conditions of concern for hypo-oestrogenic effects and reduced HDL levels theoretically increasing cardiovascular risk:
- Hypertension with vascular disease
- Current and history of ischemic heart disease
- History of stroke
- Diabetes for > 20 years or with nephropathy/retinopathy/neuropathy or vascular disease;
* Current or recent breast cancer (a hormonally sensitive tumour);
* Pregnancy;

Related topics
* Sexual Health Advice & Leaflets