Definition of Ectopic Pregnancy

An ectopic pregnancy is a pregnancy which occurs outside the uterus. Often called a "tubal pregnancy," most ectopic pregnancies occur in the fallopian tubes. However, on rare occasions, the fertilized egg may implant in the ovaries, cervix, or abdomen. Since the fallopian tubes are not large enough to accommodate a growing embryo, the pregnancy cannot continue normally. If the problem is identified early, the embryo is removed. In some cases, the embryo grows until the fallopian tube is stretched so much that the tube ruptures. Rupture of the tube is a true medical emergency because of maternal hemorrhage (severe blood loss).

Incidence

Ectopic pregnancy rates are rising. Ectopic pregnancies occur in 7 per 1,000 reported pregnancies in the United States. Maternal death rates have dropped significantly with modern technology which allows for early detection of ectopic pregnancy. Maternal death is rare (less than 1 in 2500 cases).

Risk Factors

Most ectopic pregnancies occur because the fertilized egg cannot pass through the fallopian tube to the uterus. The egg is unable to pass through narrowed or blocked tubes. Any condition which may have damaged the fallopian tubes increases a woman’s risk for an ectopic pregnancy. Pelvic inflammatory disease (PID) is the single greatest risk factor. PID is an infection of the female reproductive organs which can cause scarring of the organs. The risk factors for ectopic pregnancy include:

• Pelvic inflammatory disease
• Previous tubal pregnancy (repeat rate is about 12%)
• History of Endometriosis
• Previous tubal surgery
• Multiple induced abortions
• Pelvic adhesions (bands of scar tissue that constrict the tube, most often a result of pelvic surgery)
• Use of medications to stimulate ovulation <
• Use of an intrauterine device (IUD)—primarily because of the risk of scaring

Symptoms of an Ectopic Pregnancy

• Sharp pain in the abdomen or pelvis which may be intermittent or constant
• Irregular vaginal bleeding , often after a skipped period
• Abdominal tenderness
• Dizziness or fainting

Diagnosis of an Ectopic Pregnancy

If a woman presents with symptoms that make the physician suspect an ectopic pregnancy, the doctor will probably run a series of tests:

• A pregnancy test will be run (if the pregnancy has not already been confirmed).
• Blood levels of HCG will be evaluated. Human chorionic gonadotropin is a hormone that is present in a woman’s system during pregnancy. In a normal pregnancy, HCG levels doubles about every two days
• during the first 10 weeks of pregnancy. In an ectopic pregnancy, though, the HCG level climbs significantly more slowly. This difference helps distinguish between a normal and an ectopic pregnancy. A physician may run HCG tests over a period of days to examine the pattern of increase.
• Blood levels of Progesterone may be evaluated. Progesterone levels are high during pregnancy. In an ectopic pregnancy, progesterone levels are lower than during a normal pregnancy.
• An ultrasound will be done to determine if the uterus contains a developing fetus. The ultrasound allows the doctor to visualize the uterus and ovaries from outside the body. The ultrasound may be done abdominally or vaginally.
• Occasionally, culdocentesis is done. In culdocentesis, a needle is inserted at the top of the vagina, between the uterus and the rectum, to check for blood. The presence of blood may indicate bleeding from a ruptured fallopian tube.

Treatment of an Ectopic Pregnancy

The management of ectopic pregnancy depends on the size of the embryo and whether the tube has ruptured. In all cases, the pregnancy must be terminated. If the tube is not ruptured, the physician has several treatment options. If the embryo is small (ideally, less than 2 cm and the HCG is less than 1000mlU/ml), the physician may use the drug methotrexate to treat the pregnancy. Alternately, the embryo may be flushed out of the tube in procedure called a salpinostomy. The third treatment option is a laparsopy. A laparsocopy is a surgical procedure which requires general anesthesia (occasionally, regional anesthesia is used). During the procedure the surgeon inserts a long hollow tube (called a laparoscope) into a small incision made in or just below the navel. Using the laparascope, the physician can locate and remove the ectopic pregnancy and, hopefully, repair the fallopian tube. If the tube has ruptured, the phsycian must perform an emergency laparascopic procedure to remove the embryo. Usually, the tube must be removed, too. Follow-up care includes lab work to monitor the HCG level to ensure that all the tissue was removed.

Fertility after an Ectopic Pregnancy

If the ectopic pregnancy was treated without the loss of a tube, a woman still has a very good chance for future successful pregnancies. Loss of a tube reduces success rates (to about 40%), but a woman can still become pregnant and have a successful pregnancy with one intact tube. If infertility occurs, treatment techniques can still help a woman achieve pregnancy.

A woman who has had an ectopic pregnancy is at increased risk for another ectopic pregnancy. She should speak with her physician about her risk, and measured for early evaluation of embryo placement (use of an ultrasound as soon as pregnancy is confirmed). Women in fertility treatment are also at increased risk for ectopic pregnancy (particularly with in vitro methods). Most fertility specialists perform an ultrasound shortly after a pregnancy is confirmed to check for embryo placement and, when appropriate, the other lab tests are also performed.