Ectopic pregnancy

What is an ectopic pregnancy?

During ovulation, an egg (ovum) is released from one of the ovaries. Conception occurs when the egg meets a sperm in the fallopian tube. Normally, the fertilised egg moves down the fallopian tube and into the uterus (womb) to implant in the uterine lining (endometrium).

Ectopic pregnancy is a pregnancy that develops outside the uterus, usually in one of the fallopian tubes. In almost all cases, the embryo dies. The developing placenta cannot access a rich blood supply and the fallopian tube is not large enough to support the growing embryo.

In around 15 per cent of cases, the tube ruptures, causing pain, internal bleeding and shock. This is a medical emergency needing immediate surgery and, in some cases, a blood transfusion. In an emergency, call triple zero (000) for an ambulance or go immediately to the nearest hospital emergency department.

An ectopic pregnancy can also develop in the cervix (entrance to the womb), the abdominal cavity and the ovary itself, but these cases are rare. Around 5 in 1,000 pregnancies are ectopic.

Symptoms of ectopic pregnancy

The symptoms of ectopic pregnancy can mimic miscarriage or the symptoms of other reproductive disorders, such as pelvic inflammatory disease (PID) or endometriosis. An ectopic pregnancy can first appear as a normal pregnancy.

The symptoms of ectopic pregnancy can include:

• the usual signs of pregnancy, such as amenorrhoea (missed period), morning sickness and breast tenderness
• pain in the lower abdomen
• pain in the lower back
• cramps on one side of the pelvis
• vaginal bleeding or spotting
• sudden and severe pain in the lower abdomen (if the fallopian tube ruptures).

Risk factors for ectopic pregnancy

Ectopic pregnancy is caused by a fertilised egg not being able to move through the fallopian tube. This can be caused by a blockage in the tube or because the tiny hairs inside the tube are not able to sweep the fertilised egg towards the uterus.

Factors that can increase a woman’s risk of having an ectopic pregnancy include:

• successful reversal of a tubal sterilisation
• endometriosis
• past infection with PID or salpingitis (inflammation of the fallopian tubes) and associated scarring
• defects of the fallopian tube
• use of assisted reproductive technologies
• past ectopic pregnancy
• damage to the fallopian tube caused by a ruptured appendix.

Contraception and ectopic pregnancy

The contraceptives currently available in Australia do not increase the risk of ectopic pregnancy. However, of pregnancies that occur while using contraception, a percentage are ectopic. These include around:

• 5 per cent in women using copper IUDs or progestogen-only pills (mini pills)
• 10 per cent in women using the contraceptive implant
• up to 50 per cent in women using hormone-releasing IUDs.

If a pregnancy occurs as a result of a failed tubal sterilisation, there is also a higher risk that it will be ectopic, but the percentage is unknown.

Because implants and IUDs are extremely effective methods of contraception and pregnancy is highly unlikely, these methods can be used in women with a past history of ectopic pregnancy. The progestogen-only pill can also be considered. Women who use these forms of contraception need to be aware of the symptoms of ectopic pregnancy.

Diagnosis of ectopic pregnancy

Around 15 per cent of cases of ectopic pregnancy are diagnosed in the emergency room after the fallopian tube has ruptured. In most cases, ectopic pregnancy can be diagnosed using a range of tests, some of which are standard medical procedures for all pregnant women, including:

• pelvic examination
• blood tests
• ultrasound
• laparoscopy (‘keyhole’ surgery).

Treatment for ectopic pregnancy

A ruptured fallopian tube is a medical emergency. Laparoscopic surgery is done to remove the embryo and attempts are made to repair the fallopian tube. A blood transfusion may also be needed.

For non-emergency ectopic pregnancy, medication is often successful, but sometimes surgery is still needed. Any woman thought to have or found to have an ectopic pregnancy will need careful observation. Most women who have had an ectopic pregnancy can become pregnant again, but they will need careful follow up, as their risk of ectopic pregnancy is higher.

Early screening for ectopic pregnancy is vital

Screening and developments in early pregnancy monitoring have considerably reduced the number of deaths from ectopic pregnancy. Women who are at high risk must be monitored closely during early pregnancy through blood tests and ultrasound.

It is important to tell your doctor if your medical history includes any of the known risk factors. You should also see your doctor immediately if you have unusual pregnancy symptoms such as cramping, pain or vaginal bleeding.

Risk reduction for ectopic pregnancy

Many cases of ectopic pregnancy are caused by scarring of the fallopian tubes. Suggestions on how to reduce your risk of fallopian tube damage include:

• treating any pelvic infection promptly
• treating any sexually transmissible infection (STI) promptly
• avoiding STIs by always using a condom when having sex if the risk of an STI is at all possible.

Where to get help

• In an emergency, call triple zero (000) for an ambulance or go immediately to your nearest hospital emergency department
• Your GP (doctor)
• Obstetrician
• The Royal Women’s Hospital Tel. (03) 8345 2000