An ectopic pregnancy occurs when a fertilized egg implants itself somewhere outside the uterus. Usually, the egg implants itself in one of the fallopian tubes. However, it can also occur on an ovary, inside the abdomen, or in the cervix. Medical or surgical treatment is necessary to prevent the serious complications an ectopic pregnancy can cause.
Normally, a fertilized egg implants in the uterus. But if the fertilized egg implants somewhere other than the uterus, the pregnancy is said to be "ectopic." Ectopic simply means "located in an abnormal position."
When an ectopic pregnancy occurs, in most cases, the fertilized egg implants in one of the fallopian tubes. Because the fallopian tube is narrow and its walls are thin, the fetus only has to be about the size of a jellybean before the fallopian tube bursts, causing major bleeding.
Occasionally, an ectopic pregnancy will occur in places other than the fallopian tube. For example, the fertilized egg may implant on an ovary, in the abdominal cavity, or in the cervix.
An ectopic pregnancy is also known as a tubal pregnancy because most ectopic pregnancies occur in the fallopian tube.
Ectopic pregnancies are rare; they occur in about 1 out of every 60 pregnancies. Certain risk factors can make an ectopic pregnancy more likely:
- A history of pelvic inflammatory disease (PID)
- Women whose mothers took diethylstilbestrol (DES) while pregnant
- Sexually transmitted diseases, such as chlamydia or gonorrhea
- A previous ectopic pregnancy
- A previous tubal surgery for infertility
- Tubal sterilization procedure, such as laparoscopic tubal ligation or postpartum tubal ligation, within the past 1 to 2 years
- History of IUD (intrauterine device) use
- Pregnancy with an IUD in place
- Prolonged infertility
- Multiple sex partners
- Vaginal douching.