Miscarriage, or in medical terminology spontaneous abortion, is the termination of a pregnancy from natural causes before the time the fetus can survive for even a few minutes outside the uterus. (Induced abortion is the term used for those expulsions of an embryo or fetus that are artificially induced by mechanical means or drugs.) Miscarriage generally occurs before the twentieth week of pregnancy. A fetus born dead from natural causes after twenty weeks is called stillborn. Perhaps 50 to 78 percent of all fertilized eggs spontaneously abort. Only about 10 to 15 percent of the time are women aware that they have miscarried. Spontaneous abortions often seem to be functional in that they naturally eliminate many fetuses that may have birth defects.
Before miscarrying, a woman usually has spotting or more obvious bleeding and discharge from the vagina. The uterus contracts, causing pelvic cramps. Bleeding, discharge, and cramps become more severe if the miscarriage continues, and part or all of the contents of the uterus may be expelled. One miscarriage does not mean that later pregnancies will spontaneously abort, however, and about 70 to 90 percent who have miscarried eventually become pregnant again. Only about 1 percent of women suffer three or more miscarriages, perhaps because of anatomical, hormonal, genetic, or immunological factors.
About 85 percent of miscarriages happen in the first twelve weeks of pregnancy; the remaining 15 percent occur between thirteen and twenty weeks. The most likely reason is an abnormality in fetal development, usually as a result of extra chromosomes (about 60% of miscarriages). Occupational exposure to some chemicals may increase the chances of having a miscarriage. Other possible causes include chronic infections, unrecognized diabetes in the mother, and defects in the uterus. About one-third of the time there is no known cause for the miscarriage. Many studies have indicated that emotional disturbances in the mother's life are not usually linked with miscarriage. Miscarriage does, however, cause emotional disturbance in the lives of many women. Women tend to blame themselves: "I exercised too hard"; "Stress at work caused this"; "I fell down and hurt the baby." However, stress or physical trauma rarely results in a miscarriage, and health care professionals advise women not to blame themselves.
American society tends to define the loss of the fetus as "just a miscarriage," but most women who experience a miscarriage see the loss as a death— the death of a life or the death of a dream. Research indicates that losing a baby due to miscarriage can be a devastating experience for family members. Some women consider suicide after a miscarriage. Some couples' relationships are thrown into turmoil as a result of the loss. Some surviving siblings will feel guilt that they somehow caused the death, and will grieve in silence. However, researchers have found that families who support each other through these difficult times are likely to end up feeling stronger and more deeply committed to each other.
See also: Abortion
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JOHN D E FRAIN