An ectopic pregnancy occurs when a fertilized egg implants and grows outside the main cavity of the uterus. Pregnancy begins with a fertilized egg. Normally, the fertilized egg attaches to the lining of the uterus.
An ectopic pregnancy most often occurs in a fallopian tube, which carries eggs from the ovaries to the uterus. This type of ectopic pregnancy is called a tubal pregnancy. Sometimes, an ectopic pregnancy occurs in other areas of the body, such as the ovary, abdominal cavity or the lower part of the uterus (cervix), which connects to the vagina.
An ectopic pregnancy can't proceed normally. The fertilized egg can't survive, and the growing tissue may cause life-threatening bleeding, if left untreated.
You may not notice anything at first. However, some women with an ectopic pregnancy have the usual early signs or symptoms of pregnancy — a missed period, breast tenderness and nausea.
If you take a pregnancy test, the result will be positive. Still, an ectopic pregnancy can't continue as normal.
Signs and symptoms increase as the fertilized egg grows in the improper place.
Early warning of ectopic pregnancy
Often, the first warning sign of an ectopic pregnancy is pelvic pain. Light vaginal bleeding may also occur.
If blood leaks from the fallopian tube, you may feel increasing abdominal pain, an urge to have a bowel movement or pelvic discomfort. If heavy bleeding (hemorrhaging) occurs, you may feel shoulder pain as blood fills your pelvis and abdomen. Your specific symptoms depend on where the blood collects and which nerves are irritated.
If the fertilized egg continues to grow in the fallopian tube, it can cause the tube to rupture. Heavy bleeding inside the abdomen is likely. Symptoms of this life-threatening event include extreme lightheadedness, fainting, severe abdominal pain and shock.
When to see a doctor
Seek emergency medical help if you have any signs or symptoms of an ectopic pregnancy, including:
- Severe abdominal or pelvic pain during pregnancy
- Abnormal vaginal bleeding
- Extreme lightheadedness or fainting
- Other concerning symptoms, especially if you have risk factors for an ectopic pregnancy
A tubal pregnancy — the most common type of ectopic pregnancy — happens when a fertilized egg gets stuck on its way to the uterus, often because the fallopian tube is damaged by inflammation or is misshapen. Hormonal imbalances or abnormal development of the fertilized egg also might play a role.
Some things that make you more likely to have an ectopic pregnancy are:
- Previous ectopic pregnancy. If you've had this type of pregnancy before, you're more likely to have another.
- Inflammation or infection. Sexually transmitted infections, such as gonorrhea or chlamydia, can cause inflammation in the tubes and other nearby organs, and increase your risk of an ectopic pregnancy.
- Fertility treatments. Some research suggests that women who have in vitro fertilization (IVF) or similar treatments are more likely to have an ectopic pregnancy. Infertility itself may also raise your risk.
- Tubal surgery. Surgery to correct a closed or damaged fallopian tube can increase the risk of an ectopic pregnancy.
- Choice of birth control. The chance of getting pregnant while using an intrauterine device (IUD) is rare. However, if you do get pregnant with an IUD in place, it's more likely to be ectopic. Tubal ligation, a permanent method of birth control commonly known as "having your tubes tied," also raises your risk, if you become pregnant after this procedure.
- Smoking. Cigarette smoking just before you get pregnant can increase the risk of an ectopic pregnancy. The more you smoke, the greater the risk.
An ectopic pregnancy can cause your fallopian tube to burst open. Without treatment, the ruptured tube can lead to life-threatening bleeding.
There's no way to prevent an ectopic pregnancy, but here are some ways to decrease your risk:
- Limit your number of sexual partners.
- Always use a condom during sex to help prevent sexually transmitted infections and reduce your risk of pelvic inflammatory disease.
- Don't smoke. If you do, quit before you try to get pregnant.