Miscarriage is when a baby dies in the womb before 20 weeks of pregnancy.

Among women who know they are pregnant, about 10 to 15 out of 100 pregnancies (10 to 15 percent) end in miscarriage. As many as half of all pregnancies may end in miscarriage—we don’t know the exact number because many may happen before a woman knows she’s pregnant.

Most miscarriages happen in the first trimester (13 weeks) of pregnancy. Second-trimester miscarriage happens in just 1 to 5 out of 100 pregnancies (1 to 5 percent) between 13 and 19 weeks.

What causes miscarriage?

We don’t understand all the causes of miscarriage. Possible causes include:

  • Chromosome problems. This is the cause of more than half of miscarriages that happen in the first trimester. Chromosomes are tiny, thread-like structures in cells that carry our genes. Each person has 23 pairs of chromosomes (46 in all). One chromosome in each pair comes from the mother, and the other comes from the father. Most chromosome problems happen when an egg or sperm cell has too many or too few chromosomes. Pregnancy happens when a man’s sperm fertilizes a woman’s egg. If either has the wrong number of chromosomes, miscarriage may happen.
  • Blighted ovum. This is when a fertilized egg implants in the uterus but doesn’t develop into a baby. This is sometimes caused by chromosome problems. In early pregnancy, the woman may notice that her pregnancy symptoms have stopped, and she may have dark-brown vaginal bleeding. 
  • Smoking, alcohol and drugs. If you smokedrink alcohol, use street drugs or abuse prescription drugs, you may increase your chances of having a miscarriage.
  • Mom’s health. Some health conditions may increase a woman’s chances for having a miscarriage. Treatment of these conditions before and during pregnancy can sometimes help prevent miscarriage. If you have any of these health conditions, tell your health care provider before or as soon as you know you’re pregnant.These include:
    • Hormone problems. Hormones are chemicals made by the body.
    • Infections
    • Diabetes. This is having too much sugar in your blood. This can damage organs in your body, including blood vessels, nerves, eyes and kidneys.
    • Thyroid disease. The thyroid is a gland in your neck that makes hormones that help your body store and use energy from food.
    • Lupus and other autoimmune disorders. Immune disorders mean your immune system doesn’t work correctly and can’t protect your body from infection.

    You may have heard that getting too much caffeine during pregnancy can cause miscarriage. Caffeine is a drug found in foods, drinks, chocolate and some medicine. It’s a stimulant, which means it can keep you awake. Some studies say caffeine may cause miscarriage, and some say it doesn’t. Until we know more about how caffeine can affect pregnancy, it’s best to limit the amount you get to 200 milligrams each day (about one 12-ounce cup of coffee).

    What are the signs and symptoms of miscarriage?

    Signs and symptoms include:

    Many women have these signs and symptoms in early pregnancy and don’t miscarry. If you have any of the signs or symptoms, call your health care provider. Your provider may want to do some tests to make sure everything’s OK. These tests can include blood tests, a pelvic exam and an ultrasound. An ultrasound is a test that uses sound waves and a computer screen to show a picture of your baby inside the womb.

    How long does it take to recover from a miscarriage?

    It can take a few weeks to a month or more to physically recover from a miscarriage. Depending on how long you were pregnant, you may have pregnancy hormones in your blood for 1 to 2 months after you miscarry. Most women get their period again 4 to 6 weeks after a miscarriage.

    It may take longer to recover emotionally. You may have strong feelings of grief about the death of your baby. Grief is all the feelings you have when someone close to you dies. You may feel sad, angry, confused or alone. At times, your feelings may seem more than you can handle. You may have trouble concentrating. You may feel guilty about things that happened in your pregnancy. It’s OK for you to take time to grieve, ask your friends for support, and find special ways to remember your baby.

    If you miscarry, when can you try to get pregnant again?

    This is a decision for you to make with your partner and your health care provider. You’re most likely medically OK to get pregnant again after you’ve had at least one normal period. But you may not be emotionally ready to try again so soon. Miscarriage can be hard to handle. You may need to take time to grieve the loss of your baby. You may want to wait a while before trying to get pregnant again.

    Your provider may want you to have some medical tests to try to find out more about why you miscarried. If so, you may need to wait until after you’ve had these tests to try to get pregnant again.

    Last reviewed July 2012