Miscarriage is loss of a pregnancy up to 20 weeks; most occur by 12 weeks. Miscarriage before seven weeks of pregnancy is common; as many as 10 to 25 percent of diagnosed pregnancies end in miscarriage, according to the American Pregnancy Association. Once the fetal heartbeat is detected, the rate of miscarriage drops, according to the University of Maryland Medical Center. Medically, miscarriage is called a spontaneous abortion. Most miscarriages are caused by chromosomal abnormalities in the fetus, according to the Mayo Clinic.
Cramping
Cramping and backache are common in early pregnancy, and often accompany implantation of the embryo. But if miscarriage is occurring, cramps are more severe than menstrual cramps, according to the American Pregnancy Association. Cramping will increase if miscarriage is about to occur.
Bleeding
Spotting or bleeding is another common symptom in 20 to 30 percent of pregnancies, and can be a sign of miscarriage. Fifty percent of women who have spotting go on to have healthy babies, according to the American Pregnancy Association. Brown spotting is sometimes referred to as a threatened miscarriage. Bed rest may be prescribed, but since most miscarriages are caused by abnormal chromosomes, it likely won't stop miscarriage from occurring. However, if bleeding goes from brown spotting to bright red bleeding that increases, contains clots and is accompanied by cramping, miscarriage is likely.
Passing Tissue
Passing tissue from the vagina, especially if accompanied by bleeding and cramping, is a sign of miscarriage. If fetal tissue is passed, miscarriage is inevitable. When a medical practitioner does a vaginal examination, he can tell whether or not the cervix is beginning to open, or dilate. This is another sign of inevitable miscarriage, according to the University of Maryland Medical Center.
Decreased Pregnancy Symptoms
Sometimes the symptoms of pregnancy such as nausea, fatigue or sore breasts suddenly decrease. This sometimes happens in an missed miscarriage, when the fetus has died but has not been expelled from the uterus, according to the American Pregnancy Association. If miscarriage doesn't naturally occur, or if only part of the pregnancy tissue is passed, a dilation and curettage may need to be done to remove all the tissue. Infection can result if all tissue isn't removed, according to the Mayo Clinic. Fever, chills or vaginal discharge may occur if infection is present.
