Depo-Provera

Depo-Provera is a contraceptive medication that contains the synthetic hormone progestin. After injection into the upper arm or buttocks, the medication protects you from pregnancy for three months. Depo-Provera was approved for use as a contraceptive in the United States in the early 1990s.


How it works
Depo-Provera inhibits ovulation, thickens the cervical mucus and thins the lining of the uterus. Thickened cervical mucus is difficult for sperm to penetrate, and a thin uterine lining is a less favorable environment for egg implantation. The progestin in Depo-Provera is a chemical form of the natural hormone progesterone, which is produced during the second half of each menstrual cycle.

Effectiveness
When taken exactly as directed, Depo-Provera is nearly 100 percent effective in preventing pregnancy. With typical use (which allows for the fact that it may not always be used correctly), it's about 97 percent effective.

When Depo-Provera should not be used
Discuss your medical history thoroughly with your doctor before choosing a method of contraception. Depo-Provera should not be used if you may be pregnant. It may not be recommended if you are depressed, want a rapid return to fertility or have:
unexplained vaginal bleeding
a history of breast cancer
certain cardiovascular diseases
severe high blood pressure
a history of stroke
diabetes for more than 20 years or complications involving the blood vessels, nerves, kidneys or eyes
certain liver problems
an allergy to any of their ingredients
a blood clot in the legs or lungs
a severe blood clotting disorder
If you were exposed before birth to diethylstilbesterol (DES, a synthetic estrogen that was given to some women in the United States until the early 1970s), talk to your doctor about the risks and benefits of a combination contraceptive. Although the estrogen in this medication hasn't been shown to be unsafe for women who were exposed to DES, some doctors suggest avoiding combination contraceptives.


Patient preparation
If you'd like to use Depo-Provera, consult your doctor. He or she will ask questions about your medical history and do a physical exam.

Procedure
Your first Depo-Provera injection should be given within the first five days after your period begins. Protection from pregnancy typically begins immediately if you receive your shot during this time. Then, Depo-Provera must be given at regular 12-week intervals.
If you're late getting your next shot, begin using a backup method of birth control, such as male or female condoms, and consult your doctor. If you've had unprotected sex and don't want to become pregnant, you may want to talk to your doctor about emergency contraception (commonly referred to as the "morning-after pill").

If you've recently given birth and aren't breastfeeding, Depo-Provera should be given within five days after the birth. Your doctor may recommend waiting four to six weeks if you have a history of postpartum depression or you're at high risk for postpartum depression. If you're nursing, check with your doctor about the proper timing of these injections.


Stopping injections
To reverse the contraceptive effects of Depo-Provera, stop getting the injections. If you conceive immediately after stopping the injections, any trace amounts of hormone left in your body will be too small to have an effect on the developing baby. Conception typically occurs about nine months after you receive the last shot -- a delay compared to other methods of birth control.

Breastfeeding
Although the medication progestin is transferred through breast milk, the dose is minimal. Studies of children who nursed while their mothers were on Depo-Provera have noted no adverse effects. In fact, Depo-Provera actually enhances milk production.

Benefits
Depo-Provera is highly effective, which may decrease worry about unplanned pregnancy. It requires no special action just before sexual activity. Since Depo-Provera contains only progestin, it has no estrogen-related complications or side effects. Depo-Provera may also:
decrease menstrual bleeding, cramps and pain
decrease the risk of endometrial cancer, ovarian cancer and pelvic inflammatory disease (an infection of the female reproductive organs)
decrease the risk of ectopic pregnancy (a pregnancy in which the fertilized egg implants itself outside the uterus)
Depo-Provera can also be used by women with certain medical conditions to:

help manage the pain of endometriosis (when endometrial tissue, the tissue that lines the uterus, grows outside the uterus)
help prevent and limit sickle cell crises
help control seizures for those taking seizure medication
help decrease anemia (a condition marked by a decreased number of red blood cells or hemoglobin, a protein in red blood cells that contains iron)

Risks/disadvantages
Depo-Provera requires regular injections from your doctor. It does not offer protection from sexually transmitted diseases (STDs), including HIV (the virus that causes AIDS). It's important to practice safe sex with male or female condoms to help prevent STDs. If you're exposed to an STD, contact your doctor for testing and treatment.
Long-term use of Depo-Provera may cause a loss of bone mineral density (BMD) that may not be reversible even when the medication is no longer being used. This may be of special concern for adolescents. It's recommended that Depo-Provera not be used for longer than two years unless other birth control methods are inadequate. Depo-Provera may also contribute to falling levels of high-density lipoprotein (HDL or "good") cholesterol.

Studies have shown that women who use Depo-Provera don't have an overall increased risk of breast, uterine, ovarian, cervical or liver cancer. However, there may be a slightly increased risk of breast cancer within the first four years of use.

Side effects of Depo-Provera may include:

irregular menstrual bleeding for the first few months
amenorrhea (This causes some women to worry about unplanned pregnancy, while others consider this side effect a benefit.)
breast tenderness
weight gain
acne
headache
dizziness
abdominal pain
depression, anxiety or mood changes
decreased sex drive
Because Depo-Provera is a long-acting medication, most women who experience these side effects report a gradual decrease in symptoms for several months after discontinuing the medication. Another disadvantage of Depo-Provera is a slow return to fertility when the injections are stopped.


Complications
If you notice any of the following reactions after an injection, call your doctor immediately:
sudden difficulty breathing
sharp chest pain or coughing up bloody secretions
sudden intense headache, vomiting, dizziness, visual or speech impairment, weakness or numbness in a leg or arm
severe calf pain or swelling
unusually heavy or continuous vaginal bleeding
severe lower abdominal discomfort
persistent pain, bleeding or pus-like drainage from the injection site