An ectopic pregnancy happens when a woman becomes pregnant, but the egg settles outside of its normal location in the inner lining of the womb. The egg cannot develop normally, and the consequences can be serious for the woman.
Most ectopic pregnancies occur in the fallopian tube, but they can also happen in the neck of the womb, in the ovary, or in the abdominal cavity.
In a normal pregnancy, fertilization occurs in the fallopian tubes, where an egg, or ovum, meets a sperm cell. The fertilized egg then travels into the uterus and becomes implanted in the womb lining. The embryo develops into a fetus and remains in the uterus until birth.
An ectopic pregnancy can be fatal without prompt treatment. For example, the fallopian tube can burst, causing internal abdominal bleeding, shock, and serious blood loss.
According to the Centers for Disease Control and Prevention, between 1 and 2 percent of all pregnancies are ectopic. However, ectopic pregnancy is the cause of 3 to 4 percent of pregnancy-related deaths.
Fast facts on ectopic pregnancy
- Ectopic pregnancy involves the growth of an embryo outside of the womb during pregnancy. Most ectopic pregnancies take place in the fallopian tubes.
- An embryo cannot survive an ectopic pregnancy. However, if a rupture occurs, the consequences can be serious, and prompt treatment is essential.
- Risk factors include previous fallopian tube infections such as salpingitis, smoking, a history of infertility, use of contraceptive intrauterine devices (IUDs) and medications, and advanced age.
- Treatment options include laparoscopic surgery and methotrexane drug therapy.
At first, an ectopic pregnancy appears similar to a normal pregnancy. A woman will have a positive pregnancy test.
The woman will miss a menstrual cycle and may experience nausea. Her breasts will become tender, and she may experience fatigue.
After 4 to 10 weeks of an ectopic pregnancy, however, symptoms will start to indicate an abnormal pregnancy.
Symptoms may include:
- Pain on one side of the abdomen: This may be severe and continuous.
- Vaginal bleeding: The blood will be lighter or darker than during menstrual bleeding, and usually less viscous. If a woman does not know that she is pregnant, she may confuse vaginal bleeding for menstrual blood.
- Shoulder tip pain: This is a common sign of internal bleeding. The bleeding may irritate the phrenic nerve, and this leads to pain in the shoulder.
- Pain when passing urine or feces: This may also indicate an ectopic pregnancy.
- Fainting or collapse: If the fallopian tubes rupture, this may cause a woman to faint and collapse. This would be considered a medical emergency.
Other signs of internal bleeding include:
- pale skin
Fallopian tube rupture can occur after between 6 and 16 weeks of pregnancy. A ruptured fallopian tube can, however, be treated successfully.
A fertilized egg cannot survive outside the womb, and therefore will not survive an ectopic pregnancy. The pregnancy cannot be saved.
A complication of ectopic pregnancy is more likely if diagnosis or treatment is delayed, or if the condition is never diagnosed.
Internal bleeding: A woman who has an ectopic pregnancy and does not receive timely diagnosis or treatment is more likely to experience severe internal bleeding. This can lead to shock and serious outcomes.
Damage to fallopian tubes: Delayed treatment can also result in damage to the fallopian tube, significantly increasing the risk of future ectopic pregnancies.
Depression: This can result from grieving over the loss of the pregnancy and worrying about future pregnancies.
It is important to remember that pregnancy remains possible even if a fallopian tube is removed. If both tubes are removed, in-vitro fertilization (IVF) remains an option if a woman wishes to conceive a child.
The following factors lead to a higher risk of an ectopic pregnancy:
- Previous ectopic pregnancy: Women who have already had one ectopic pregnancy have a 10 percent risk of another.
- Age: The older a women is when she falls pregnant, the higher the risk of an ectopic pregnancy.
- Infection: A history of inflammations and infections of the fallopian tube, uterus, or ovaries can increase the risk of subsequent ectopic pregnancies. Infections linked to ectopic pregnancy include pelvic inflammatory disease (PID) and salpingitis. Approximately 50 percent of ectopic pregnancies are linked to salpingitis.
- Sexually transmitted infections: Some sexually transmitted infections (STIs) increase the risk of PID, such as gonorrhea or chlamydia. PID can lead to ectopic pregnancy.
- Smoking: This has been associated with an increased chance of ectopic pregnancy.
- Fertility treatment: Medications used to stimulate ovulation during fertility treatment have been linked to a higher chance of ectopic pregnancy. A history of infertility can also be connected to the development of the condition.
- Damaged or abnormally shaped fallopian tubes: These can be caused by surgery, for example, and can mean a higher risk of ectopic pregnancy.
- Previous surgery: Previous Cesarean section and fibroid removal surgeries are risk factors.
- Taking contraceptive pills or using an intrauterine device (IUD): The use of progestin contraceptives and IUDs can increase the risk of ectopic pregnancy.
- Tubal ligation: Tubal ligation is surgery received by a woman to prevent further pregnancy. If she does then become pregnant, the pregnancy could be ectopic.
However, it is possible for a woman to have an ectopic pregnancy without any of these risk factors.
A blood test can detect a hormone called chorionic gonadotropin (hCG), which is produced in increasing quantities throughout the pregnancy.
In women with a normal pregnancy, levels will double around every 48 hours. In an ectopic pregnancy, levels will be lower and will not double. Lower hCG levels could signal an ectopic pregnancy.
A urine test can tell whether an egg has been fertilized, but not whether a pregnancy is ectopic or normal. A transvaginal ultrasound can sometimes confirm an ectopic pregnancy. During this diagnostic test, a radiologist or obstetrician will produce images of the uterus using soundwaves.
If it is too early to detect an ectopic pregnancy, and the diagnosis is not confirmed, a doctor may use blood tests to monitor the condition of the patient with blood tests.
Continuous monitoring will then occur until the ectopic pregnancy can either be confirmed or ruled out through an ultrasound.
If diagnosis is made before the rupture of the fallopian tube, treatment options are available.
Keyhole surgery can be performed to remove the ectopic tissue. This is also known as a laparoscopy.
In a laparoscopy, the surgeon makes a small incision in or near the navel and inserts a device called a laparoscope to view the area.
Other surgical instruments are inserted into a tube, or through other small incisions, to remove the ectopic tissue.
If the area is damaged, surgeons might be able to repair the fallopian tubes, but they will probably have to remove the affected tube as part of this procedure.
If the other fallopian tube is still intact, a healthy pregnancy is still possible.
If severe internal bleeding has occurred, a larger incision may be needed. This procedure would be called a laparotomy.
Drug therapy is possible in cases where the ectopic pregnancy is detected early.
The doctor injects methotrexate into the muscle of the patient or directly into the fallopian tube. This halts cell growth and dissolves existing cells. If blood hCG levels do not drop, the patient may need another injection.
Adverse effects of methotrexate include nausea, vomiting, abdominal pain, and possibly mouth sores. The effect of methotrexate may be hindered if the woman consumes heavy quantities of alcohol.
Some physicians prefer a "watchful waiting" approach, as an ectopic pregnancy may terminate without intervention.
It is not possible to fully prevent an ectopic pregnancy. However, a woman can reduce the risk of PID, as this can damage the fallopian tubes and is a known risk factor for ectopic pregnancy.
STIs such as chlamydia and gonorrhea are a main cause of PID. Using a male condom can help reduce the risk of catching an STI. Choosing safe sex every time can reduce the chance of infection and increase the ability for a woman to have healthy pregnancies in the future.
As smoking is known to increase the risk of having an ectopic pregnancy, quitting also reduces the risk.
Any woman who believes that she is pregnant after a previous ectopic pregnancy should tell her doctor immediately. This will allow the doctor to determine whether the next pregnancy is also ectopic.