Miscarriage is one of the causes of vaginal bleeding during pregnancy in about 15 to 20 percent of women, according to MedlinePlus. Most miscarriages happen during the first seven weeks of pregnancy, though technically they can occur up until the 20th week after conception. Clot-like bleeding and severe pain usually accompany a miscarriage; failure to get prompt medical attention can lead to fatal infections.
Most miscarriages can’t be prevented even with medical help, but prompt medical attention usually helps protect future childbearing abilities. Many women who have miscarriages deliver healthy children from future pregnancies. A number of women also miscarry without realizing they were actually pregnant. Women over the age of 35 are at a heightened risk of miscarriage, and once a woman has a miscarriage she’s much more likely to suffer from another. Uncontrolled diabetes, immune system problems or genetic abnormalities in a fetus usually cause miscarriages.
Sometimes light bleeding occurs right after a fetus implants itself into the womb, according to the American Pregnancy Association. Such blood is usually lighter in color than menstrual blood and usually happens about 6 to 12 days after conception.
A Pap smear tests for cervical cancer and other abnormalities, and are often ordered during pregnancy. Sometimes the test itself causes an inflamed cervix which can cause light bleeding or “spotting,” according to the Baby Center.
Sexual intercourse is usually safe during pregnancy, but can sometimes can an inflamed cervix. Anytime the cervix becomes inflamed, vaginal bleeding can result and is not something for an expectant mom to fret over unless the blood becomes thick, according to the Baby Center. However, pregnant women who bleed even lightly after intercourse should not have sexual relations again until they speak to their doctors, according to the American Pregnancy Association.
An ectopic or tubal pregnancy is one of the most potentially serious causes of vaginal bleeding during pregnancy, according to the Mayo Clinic. When a hopeful mom’s fetus nests in her fallopian tube instead of her uterus, ectopic pregnancy results. The Mayo Clinic notes that medical experts don’t exactly know why a few women have tubal pregnancies, but that women who had a lot of sexual partners before conception appear to be at heightened risk for this problem.
Ectopic pregnancies cause serious bleeding and pain and can become life-threatening medical emergencies. Such pregnancies must be medically terminated with drugs or surgery. Tubal pregnancies usually are detected within the first trimester; failure to promptly address this condition can lead to loss of reproductive organs and even death.
American Pregnancy Association: Bleeding During Pregnancy
Baby Center: Vaginal Bleeding or Spotting During Pregnancy
Mayo Clinic: Ectopic Pregnancy