While some degree of bleeding is common for many pregnant women, bleeding typically only occurs within the first trimester. Contact your doctor if vaginal bleeding is heavier than your usual menstruation, if it lasts longer than a day, if it is accompanied by severe abdominal cramps or if you experience it in the second or third trimester. These are all possible signs of a more serious complication.
During the first trimester, bleeding can occur frequently for many women. The American Pregnancy Association estimates that between 20 and 30 percent of pregnant women experience slight to moderate vaginal bleeding. It typically lasts for less than a day; a longer duration or heavier bleeding may be a symptom of a more serious medical complication such as miscarriage. The American College of Obstetricians estimates that miscarriages occur in up to 15 percent of pregnancies.
Vaginal bleeding can occur because of a number of reasons. Less serious causes for vaginal bleeding within the first trimester can include implantation, urinary tract infection or cervical changes that make the vagina more sensitive. More serious causes include miscarriage, ectopic pregnancy or molar pregnancy. During the second and third semester, causes for vaginal bleeding can include preterm labor, cervical problems or placenta previa, a serious complication in which the placenta blocks the birth canal.
Even though minimal vaginal bleeding lasting for a few hours is common during the first trimester, be sure to let your doctor know about it at your next visit. The Mayo Clinic recommends that if the bleeding lasts for more than 24 hours, contact your health care provider within the next day. If you experience heavy vaginal bleeding, severe cramps or pass tissue through your vagina, contact your doctor immediately, since these are signs of miscarriage.
While vaginal bleeding does not necessarily mean a miscarriage is imminent, bleeding is the No. 1 sign of miscarriage. According to the American Pregnancy Association, around 50 percent of women who bleed during their pregnancy have miscarriages. Other signs of an impending miscarriage include intense cramping in the lower stomach, abdominal pain, chills, fever and passing tissue through the vagina. Most miscarriages occur within the first trimester.
Since vaginal bleeding during the first trimester is common and typically not a sign of a more serious complication, treatment is not usually required, though your doctor may recommend getting some rest. If the bleeding is due to a cervical infection, your doctor may choose to treat it with an antibiotic. If the bleeding is due to a miscarriage or ectopic pregnancy, your doctor may prescribe medication or recommend surgery to eliminate any remaining tissue.