In a normal pregnancy an egg is released and fertilized by sperm in one of the fallopian tubes. The egg then moves to the womb and implants itself in the lining where the cells split and growth begins.
An ectopic pregnancy is when there is perhaps damage to the fallopian tube and the egg doesn't move to the womb but implants itself in the fallopian tube making it impossible for the egg to grow and develop normally. In a few cases this is only detected during routine pregnancy testing and the woman experiences no obvious symptoms. Most women however have abnormal vaginal bleeding and abdominal pain ranging from mild to severe. These symptoms can appear anywhere between week five and week fourteen. If an ectopic pregnancy is left to develop growth of the egg can cause the fallopian tube to split or rupture, causing life threatening internal bleeding so it is vital to detect and treat an ectopic pregnancy as early as possible.
While in around half the cases of ectopic pregnancy the egg dies before it can grow, a medication called methotrexate is sometimes administered. This stops the egg developing and allows the pregnancy tissue to be absorbed into the woman's body.
Because an ectopic pregnancy can appear to be a normal pregnancy, taking in some cases many weeks to diagnose, many women need counseling and support to deal with the devastating loss.