A pregnancy that takes place outside the uterus is called an ectopic pregnancy. In a normal pregnancy, the fertilised egg implants itself in the uterine wall and the fetus grows there. In an ectopic pregnancy, the implantation can take place anywhere outside the uterus, in the fallopian tubes (tubal pregnancy), ovaries (ovarian pregnancy) or in the abdomal cavity.
Ectopic pregnancy is a complication that has to be medically terminated. Of the ectopic pregnancies, more than 97% take place in the fallopian tubes.
What are the causes?
An ectopic pregnancy is caused by the inability of the fertilised egg to travel to the uterus for successful implantation. This may be because of an abnormality of the fallopian tubes which prevents the egg form travelling downwards. Women who have undergone tubal sterilisation or who have had successful reversal of the sterilisation are more likely to contract infections and are more at risk for ectopic pregnancies.
There are other risk factors that may increase the chances of an ectopic pregnancy are:
Pelvic inflammatory disease
Previous ectopic pregnancy
Hormonal imbalance leading to impaired fallopian tube contraction
Placement of an intra-uterine device.
What are the symptoms?
Some of the symptoms of an ectopic pregnancy may be the same as those which occur during a normal pregnancy, and, thus may not be immediately discernible. These may include abdominal pain, vaginal bleeding, weakness and dizziness. They may also be accompanied by tenderness in the breasts, nausea, low back pain, and stomach cramps. Occasionally there is major bleeding into the abdomen and the patient may present in a state of shock with a rapid pulse and low blood pressure.
How is it diagnosed?
Ectopic pregnancies are often difficult to diagnose and the first clue may be that the periods become irregular. A pregnancy test that measures the level of the hormone human chorionic gonadotropin (HCG) is able to discern whether the pregnancy is normal, in which case, the hormone levels double every day or ectopic pregnancies when the tests do not follow this pattern.
Some other tests that may be done to make the diagnosis are – white blood count, ultrasound examination and laparoscopy.
What is the treatment?
The treatment measures may be chemical or surgical. Chemical treatment involves drug therapy with methotrexate. It is a non-urgent form of treatment in which the fetus is dissolved without harming the tubes and the surrounding organs. The drug brings down the HCG levels in the blood thus nullifying the pregnancy. The HCG levels are brought down to zero within four weeks.
The second form of treatment is surgery. Laparotomy is the procedure through which all of the fetus and other products of conception are removed. The ruptured surrounding organs are also cleaned and repaired. The operation involves making a 5 cm incision in the abdominal wall through which the fallopian tubes are accessed. The ectopic pregnancy is then removed and the wound is closed.
What are the chances for future pregnancies?
There is a chance that the next pregnancy may also be ectopic. If one of the fallopian tubes is removed during surgery (salpingectomy), the chances of conception may be reduced. However, under supervision, pregnancy can be attempted again. Physical healing depends on the patient's general health.