Alternate Names: Tubal pregnancy; Cervical pregnancy; Abdominal pregnancy
Causes and Risks:
Ectopic pregnancies are usually caused by conditions that obstruct or slow the passage of a fertilized ovum (egg) through the Fallopian tube to the uterus. This may be caused by a physical blockage in the tube, or by failure of the tubal epithelium to move the zygote (the cell formed after the egg is fertilized) down the tube and into the uterus.
Most cases are a result of scarring caused by previous tubal infection or tubal surgery. Up to 50% of women with ectopic pregnancies have a medical history of salpingitis or PID (pelvic inflammatory disease). Some ectopic pregnancies can be traced to congenital tubal abnormalities, endometriosis, tubal scarring and kinking caused by a ruptured appendix, or scarring caused by previous pelvic surgery and prior ectopic pregnancies. In a few cases, the cause is unknown.
On occasion, a woman will conceive after elective tubal sterilization. The risk of an ectopic pregnancy occurring in this situation may reach 60%. Women who have had surgery to reverse previous tubal sterilization in order to become pregnant also have an increased risk of ectopic pregnancy (when reversal is successful).
The administration of hormones (specifically estrogen and progesterone) can alter the normal ciliary movement of the tubal epithelium. Slow movement of the fertilized egg down the fallopian tube can result in tubal implantation. Women who become pregnant despite using progesterone-only oral contraceptives have a 5-fold increase in the ectopic rate. Progesterone-bearing IUDs increase the risk of ectopic pregnancy from 5% (in non-medicated IUDs) to 15%, and the "morning after pill" is associated with a 10-fold increase in risk (when its use fails to prevent a pregnancy).
The incidence data for ectopic pregnancies ranges from 1 in every 40 to 100 pregnancies. In any case, the incidence of ectopic pregnancy is on the rise (the rate increased four-fold between 1970 and 1992).
Increased risk is associated with women who have a history of salpingitis and/or PID, tubal surgery of any type (including tubal ligation and reversal of), or prior ectopic pregnancy. The incidence in the U.S. is higher in black women than in Caucasian women.
Prevention:
Forms of ectopic pregnancy, other than tubal, are probably not preventable. However, tubal pregnancies, which make up the majority of ectopic pregnancies, may be prevented in some cases by avoiding those conditions that might cause scarring of the Fallopian tubes. Such prevention may include:
- avoiding risk factors for PID (multiple partners, intercourse without a condom, and contracting sexually transmitted diseases, also called STDs)
- early diagnosis and adequate treatment of STDs
- early diagnosis and adequate treatment of salpingitis and pelvic inflammatory disease (PID)
Symptoms:
If rupture and hemorrhaging occurs before successfully treating the pregnancy, symptoms may worsen and include:
- Severe, sharp, and sudden pain in the lower abdominal area
- feeling faint or actually fainting
- referred pain to the shoulder area
Signs and Tests:
A pelvic examination may reveal uterine adnexal (Fallopian tube or ovary region) tenderness.
This disease may also alter the results of the following tests:
- serum progesterone (found to be less than 15 ng/ml in 80% of women with ectopic pregnancies and greater than 15 ng/ml in 90% of women with normal intrauterine pregnancies)
Treatment:
In the event that pelvic-organ rupture has occurred because of the ectopic pregnancy, internal bleeding and/or hemorrhage may lead to shock. Nearly 20% of ectopic pregnancies present themselves in this manner. This is an emergency condition. Therefore, initial treatment may be to address shock by keeping the woman warm, elevating her legs, and administering oxygen. Treatment with intravenous fluids and sometimes a blood transfusion is performed as soon as possible.
Surgical laparotomy is performed to stop the immediate loss of blood (in cases in which rupture has already occurred), or to confirm the diagnosis of ectopic pregnancy, remove the products of conception, and repair surrounding tissue damage as much as possible.
In non-emergency cases, mini-laparotomy or laparoscopy are the most common surgical treatments. Such procedures have similar outcomes. However, they are less invasive and are available at a lower cost because they require minimal hospitalization or outpatient treatment.
Non-surgical (medical) management is being implemented in many medical centers for ectopic pregnancies without suspected immediate danger of rupture. In such cases, methotrexate is administered with careful outpatient monitoring of the woman and serial quantitative HCGs and CBCs.
Prognosis: About 85% of the women who have experienced one ectopic pregnancy are later able to achieve a normal pregnancy. A subsequent ectopic pregnancy may occur in 10 to 20 % of cases. Some women fail to become pregnant again, while others become pregnant and spontaneously abort during the first trimester. The maternal death rate from ectopic pregnancy in the U.S. has decreased in the last 30 years to < 0.1%. Fetal death rate is nearly 100%.
Complications:
- Rupture, with resulting hemorrhage leading to shock and the risk of requiring a blood transfusion or rarely of death, is the most common complication.
- Infertility occurs in 10 to 15% of women who have experienced an ectopic pregnancy.
A woman who has an early pregnancy or who has had the opportunity to become pregnant and has symptoms (especially lower abdominal pain and/or abnormal vaginal bleeding) should notify her health care provider. Ectopic pregnancy can occur in any woman who is sexually active, regardless of contraceptive use.
