by Anai Rhoads

If you don't see your question here, look in "Grief and Loss's" frequently asked questions.

Intercourse, falling, and exercise does not typically cause a miscarriage. The fetus is well protected by the mother's bones and muscle as well as by the amniotic fluid. There is also no evidence that conceiving while taking birth control pills increases the risk of miscarriage. Becoming pregnant while using an IUD, however, does make you more likely to miscarry or develop an infection.

As many as 25 percent of all pregnancies end in miscarriage, half of them before the woman even realizes she is pregnant. Fortunately, most women who miscarry, even more than once, can become pregnant again and give birth to a healthy baby.

What are the warning signs?

Any bleeding from the vagina during pregnancy suggests the possibility of miscarriage. Call your doctor about any abnormal vaginal bleeding, even if you do not think you are pregnant. Bleeding or spotting may be the first sign that you are pregnant and that the pregnancy is at risk. Staining or bleeding does not necessarily mean that you will miscarry, however. About 15 to 25 percent of pregnant women have some spotting or bleeding early in pregnancy, and about half of these pregnancies carry successfully to term.

Bleeding that signals possible miscarriage is usually light. It can be brown or bright red and may repeatedly occur over many days. If the bleeding persists or increases, the chances of losing the baby are greater. Cramping or low backache usually develops at some point after the bleeding has started.

If you have been bleeding and an ultra sound scan (sonogram) indicates that the fetus is alive, your doctor probably will ask you to rest in bed as much as possible and avoid sexual activity. The doctor will monitor you to be sure that:

•Your cervix is closed (If it's open, it's more likely you will miscarry).
•He or she will check the discharge/blood for clotting that would indicate whether or not it contains the fetus.
•You will be given a sonogram to see if there are any fetal heart movements, and if the fetus is growing properly.

More than 90 percent of first trimester pregnancies continue when ultra sound scans indicate that the baby is alive.

Rarely, early in pregnancy, fluid is suddenly released from the vagina without bleeding or pain. If you experience this, call your doctor immediately. You will probably be instructed to stay in bed and watch for further discharge, bleeding, cramping, or fever.

Inevitable Miscarriage

When bleeding and pain are accompanied by the breaking of membranes (the amniotic sac surrounding the fetus) and the widening of the cervix, the pregnancy is viewed as an inevitable miscarriage. Uterine contractions to expel the fetus usually begin soon after these symptoms develop.

Incomplete and Missed Miscarriages

In some miscarriages, the body does not expel all the of pregnancy. This is called an incomplete miscarriage. In about 2 percent of pregnancies, the body does not discharge the fetus or placenta for several weeks, even though the fetus has died. This is known as a missed miscarriage. This can happen while a woman has neither menstrual periods nor any signs of pregnancy. Breasts may return to their pre-pregnancy state, or the woman may lose a few pounds. (Note: Not all missed miscarriages are preceded by warning signs).

An incomplete or missed miscarriage that takes place early in pregnancy is usually removed with either suction or dilation and curettage (D&C) - "opening" the uterus and scraping out its contents, through the vagina, with an instrument called a curette. These procedures not only clear the uterus but also prevent infection. When incomplete miscarriage occurs later in pregnancy, the doctor may have to induce labor to remove the fetus.

How can I minimise the risk?

Most miscarriages are caused by chromosomal (genetic) abnormalities and other physical factors that are beyond your control. There are, however, steps you can take to reduce the risk of losing a pregnancy.

•Smoking increases the risk of losing a genetically normal baby. One study showed that women who smoked more than 10 cigarettes a day were about twice as likely to miscarry, regardless of their age. The risk of losing a pregnancy increases with the number of cigarettes a woman smokes.
•Don't drink alcoholic beverages. Having an alcoholic drink twice weekly doubled the risk of losing normal babies in one study; drinking alcohol every day tripled the risk of such miscarriages. Similarly, consuming large amounts of caffeine, more than 3-4 cups of coffee per day (or the equivalent in other substances that contain caffeine, such as chocolate, or tea) slightly increases the chance of miscarriage.
•Avoid radiation and poisons. Exposure to high levels of radiation or toxic substances increases the risk of miscarriage. Arsenic, lead, formaldehyde, benzene, and ethylene oxide can cause miscarriage. Make sure you are not exposed to these substances at work, home or anywhere else while pregnant or trying to conceive.
•Prevent trauma to the abdomen. Injuries from the steering wheel or seat belt in a car, especially during the second trimester, sometimes cause miscarriage.
•Certain prescription and over-the-counter drugs are associated with fetal abnormalities and miscarriages. Consult your doctor before taking any medication when you are pregnant or trying to conceive. Some drugs can damage the fetus and cause miscarriage before you even know you are pregnant. Check out ALL medications with your doctor.

What are the causes of miscarriage?

In general, miscarriage is more common in women over 35 years old and in pregnancies involving more than one fetus. In some multiple pregnancies (twins, triplets, or more), one or more of the fetuses survives even after another one dies. The dead fetus is expelled from the mother's body when the surviving baby is born.

About 1 in 200 women has repeated miscarriages, which physicians call recurrent spontaneous abortion. In many cases, even these miscarriages happen by chance and do not signal a problem in either or both partners. Often no cause is found.

•Chromosomal Abnormalities -- Problems in the chromosomes of the embryo, by far the most common reason for loss of pregnancy, are found in more than half of miscarriages occurring in the first 13 weeks. Miscarriages apparently eliminate about 95 percent of fertilized eggs or embryos with genetic problems - perhaps nature's way of ending a pregnancy in which the child would be unable to survive. Spontaneous abortions of this type usually occur before the woman knows that she is pregnant.

Sometimes, however, chromosomal abnormalities are caused by the parent's genes. This is more likely if the woman has had repeated miscarriages or if either parent has relatives or a child with birth defects. Genetic testing of fetal material from the miscarriage can help the doctor identify the problem.

•Immune System Problems -- Some women have repeated miscarriages because their bodies see each baby as an invading organism and attack it with antibodies. Ordinarily, many elements of the immune system work together to ensure that the mother's body does not reject the baby. But when this coordination fails, a miscarriage follows. Treatments for such problems in the immune system are experimental and should not be tried until other causes for repeated miscarriage have been ruled out.

•Hormone Imbalance -- Some women do not make enough progesterone, the hormone that prepares the lining of the uterus to nourish a fertilized egg; and if the uterine lining cannot sustain an egg, miscarriage will occur. Progesterone supplements, given by injection or in vaginal or rectal suppositories, can correct this problem. The medication can also make it more difficult for a dead fetus to be expelled. A blood test and a biopsy of a small amount of tissue taken from the uterine lining can determine whether you are producing enough progesterone naturally.

•Illness -- Miscarriages are much less common in the third trimester. Those that occur are more likely to be due to maternal factors, such as an illness in the mother, than to genetic abnormalities in the baby.