Provera is a prescription drug containing medroxyprogesterone acetate, a type of synthetic progesterone. Progesterone is one of the hormones that controls the menstrual cycle and ovulation, the monthly release of an egg from the ovaries. Progesterone also helps to prepare the womb lining for pregnancy and shed the lining each month when pregnancy does not occur (a process you know as your monthly period).
Why is Provera Prescribed?
Provera is most commonly used to treat various disorders related to the menstrual cycle, which are often the result of a hormonal imbalance. These disorders include irregular or abnormal uterine bleeding, amenorrhea (lack of periods), excessive bleeding and endometriosis, a condition in which cells that normally line the uterus grow outside the womb or in other parts of the body.
"Provera is most often used to induce a withdrawal bleed or a 'period' in women who ovulate or menstruate infrequently," explains Michele Hakakha, M.D., a board-certified obstetrician and gynecologist based in Los Angeles and co-author of Expecting 411: Clear Answers and Smart Advice for Your Pregnancy. It may also be prescribed for a short period if a woman is trying to conceive, in conjunction with the ovulation-stimulating drug Clomid.
Provera and Ovulation Stimulation
When prescribed for women trying to get pregnant, Provera is usually given for 10 days. After that time a woman can expect bleeding from two to 10 days later. "This regimen is often used for women who are trying to conceive, to initiate an artificial period so that the fertility drug Clomid (clomiphene citrate) can be started. Clomid is started on day three, four or five of a menstrual cycle and helps ensure ovulation," says Dr. Hakakha.
Provera does help regulate the menstrual cycle, but it can also interfere with ovulation, says Dr. Hakakha. "Typically Provera is used for short periods of time in specific situations (for example, to bring on a period) and is rarely used continuously by women trying to conceive, as it can prevent ovulation and thin the lining of the uterus, making implantation of an embyro very difficult," Dr. Hakakha continues. Few women take Provera because they're trying to conceive.
Provera and Pregnancy
Not only can Provera interfere with ovulation, it is also not recommended for use during pregnancy. "Provera is a type of progesterone that is used to stop menstrual bleeding and when the drug is stopped, it causes withdrawal bleeding," says Daniel Roshan, M.D., a board-certified obstetrician and assistant professor at the New York University School of Medicine, who specializes in high-risk fetal medicine. "There is no use for it in pregnancy; however, other kinds of progesterone are used to support and maintain the pregnancy."
"Provera is for menstrual irregularity, and once a woman is pregnant, should not be taken," advises Dr. Roshan. "Progestrone suppositories or Prometrium (another type of synthetic progesterone) are okay to take if needed."
Oddly enough, the side effects of Provera are similar to the side effects of pregnancy: nausea, vomiting, breast tenderness, and headaches. But if you become pregnant or are thinking about becoming pregnant while taking Provera, you should tell your healthcare practitioner right away.
Provera does not cause miscarriage, but some studies have shown that there may be a link between certain birth defects in mothers who are exposed to progestins such as Provera during the first trimester of pregnancy. Provera has been classed as a category X drug by the U.S. Food and Drug Administration, meaning that it can cause birth defects and is contraindicated for use in pregnancy.
Although Provera may affect ovulation and impair fertility, you are not advised to take Provera as a substitute for some other form of contraception because it does not prevent the release of an egg (ovulation). As Dr. Hakakha points out, Provera can prevent ovulation and thin the uterine lining, making it more difficult for an embryo to implant. "It is not, however, a form of birth control," she adds. Ask your doctor which type of contraception you should use while taking Provera; to avoid any drug interactions, consider a non-hormonal method.
Copyright © 2011 Meredith Corporation.