What is an ectopic pregnancy?
An ectopic pregnancy is a pregnancy that develops outside the uterine cavity. Under normal circumstances, an ovum is fertilized in the Fallopian tube and then implants in the uterus. In the case of an ectopic pregnancy, the egg fails to reach the uterus and develops in a fallopian tube (tubal pregnancy, which occurs in 96% to 98% of ectopic pregnancies), in an ovary, on the cervix or in the abdomen.
What's more, in an ectopic pregnancy, the fetus cannot develop. It sometimes dies of its own accord, or an operation is required to halt its growth and remove it. In fact, if the fertilized egg is not removed and the pregnancy continues, medical intervention is mandatory. Treatment is then urgently required, as the growth of the pregnancy can lead to the bursting of the Fallopian tube, causing internal haemorrhage. An ectopic pregnancy is still the leading cause of death for women in the 1st trimester of pregnancy. There are around 2 ectopic pregnancies for every 100 births, and one ectopic pregnancy for every 13 miscarriages.
What are the causes and risk factors of an ectopic pregnancy?
The exact cause of an ectopic pregnancy is still unknown. However, it is believed that an ectopic pregnancy can be explained by the fact that a fertilized egg that is too large has not been able to travel all the way down the Fallopian tube to reach the uterus, and therefore gets stuck there. This is known as a tubal pregnancy.
Sometimes, the spermatozoon has fertilized the egg when it was not in the fallopian tube. The egg then implants in an ovary, the peritoneal cavity or the fallopian tube. In many cases, it is an anomaly in the fallopian tube that has blocked the migration of the egg.
It is thought that risk factors such as :
- STDs
- A history of salpingitis (infection of the fallopian tubes following a chlamydia infection)
- Pelvic inflammatory disease (fallopian tubes, ovaries or uterus). Often caused by gonorrhea or chlamydia infection)
- Repeated curettage or aspiration
- Active or passive smoking (estimated to cause 1 in 5 EPs)
- A history of EP
- Surgery to overcome infertility diethylstilbestrol (synthetic hormone prescribed to women in France between 1950 and 1977 during pregnancy to prevent miscarriage, prematurity, etc.)
- Mother's age during pregnancy
- Medically assisted reproduction (MAP)
- IUD (in very rare cases)
- Tubal, pelvic or abdominal surgery
- abortion
- Delayed menstruation
- Unusual and/or irregular periods
What are the symptoms of an ectopic pregnancy?
At the start of an ectopic pregnancy, the fertilized egg develops normally.
Symptoms include