There are multiple causes of bleeding during pregnancy, most of which are not life-threatening. Mothers are naturally anxious about the prospect of pregnancy loss, complications or preterm birth. Small amounts of bleeding after sex or vaginal exams may be normal. Blood-tinged mucus discharge at term is a sign that labor will begin soon. However, a woman should seek medical care if she is bleeding heavily, is in pain or has cramping that doesn't subside with fluids and rest.
Implantation
Spotting at ten days to two weeks after conception is a common and benign occurrence. It is a time when dividing cells have nearly reached the embryonic period and are becoming firmly embedded in the uterine wall. Many women with healthy pregnancies experience very light bleeding without cramps during the first months, especially during times when a menstrual period would normally have been expected.
Ectopic Pregnancy
By the fourth day after fertilization, the cells have developed into a blastocyst that normally makes its way to the uterus. When the blastocyst implants outside the uterine cavity, the result is an ectoptic pregnancy. Although a woman has the signs and symptoms of very early pregnancy, the embryo cannot develop outside the womb. Pain, which may be constant, usually precedes bleeding. Symptoms may begin between five and ten weeks, marked by brown bloody discharge that resembles a menstrual period, or spotting. According to The Nemours Foundation, 95 percent of ectopic pregnancies implant in the fallopian tubes. Doctors can determine if the pregnancy is ectopic by measuring hormone levels in the blood and using ultrasound imaging. Early treatment may allow preservation of the fallopian tube. Surgery is required to save the mother's life if the tube ruptures.
Miscarriage
Bleeding during the first half of pregnancy is called a threatened abortion. Bleeding may be bright red or brown, slight, and persist for several days. Lower abdominal cramping or back pain may accompany bleeding. Heavy bleeding does not always indicate a miscarriage but should be evaluated by a healthcare professional. Many women feel better if they rest, but normal activity is not thought to change the outcome. According to an article published in the October 2005 issue of "American Family Physician," approximately 20 percent of known pregnancies end in miscarriage, more than half because of chromosomal abnormalities in the embryo.
Placenta Previa
Painless bleeding that is sudden in onset during the third trimester could be because of placenta previa, a condition in which the placenta either covers or is at the margin of the cervical opening. As the cervix begins to dilate, bleeding occurs and serious hemorrhage may result. Placenta previa is more common in women who are over the age of 35, have had many babies, are carrying twins or who have had previous cesarean births. Smokers are also at increased risk. The diagnosis can be confirmed by ultrasound.
