What causes ectopic (tubal) pregnancies? Can anything be done to prevent one from happening? --Petra

An ectopic pregnancy occurs when the embryo attaches somewhere other than inside the uterus - such as the inner wall of the fallopian tube (most common), the ovary (less common) or the pelvic sidewall (least common). While an abdominal pregnancy may in rare cases continue to term, tubal and ovarian ectopics must be removed to prevent rupture and life-threatening bleeding. I am frequently asked if the pregnancy can be transferred into the uterus, or even to the male partner ... shucks, we just don't have that worked out.

Most women with ectopic pregnancies have no known risk factors. But we do know that if you have had an infection in the fallopian tubes (pelvic inflammatory disease, or PID) or tubal surgery, you are more likely to have an ectopic pregnancy. If you have had previous ectopic pregnancies, you have a 25-50 percent chance of having another.

But there have been major advances in the treatment of tubal ectopics that make it a far less difficult situation to manage. If the pregnancy is detected early enough, we can usually treat it medically using the drug methotrexate, rather than resorting to surgery. Early detection and treatment also minimizes the risk of tubal rupture and emergency surgery. Suspicion is the key to early detection. Symptoms associated with ectopic pregnancy are generally pain on one side, spotting, pregnancy symptoms and a mass or fullness on the pelvic exam. So if you have any of these signs, or if you have any of the high-risk factors and get pregnant, you should have an ultrasound evaluation.