Ectopic pregnancy

Of all women that get pregnant, around 2% of them will develop an ectopic pregnancy. It can be a life threatening condition that needs to be diagnosed as soon as possible. What is it, why does it happen and how can it be treated? Let’s find out!

Ectopic pregnancy is a pregnancy that develops outside the uterine cavity. The word ectopic comes from the Greek terminology “ektopos” and means out of place. A normal pregnancy develops in the uterus, therefore an extrauterine one is not normal nor healthy. Don’t know how a normal pregnancy happens? Read our previous post.

In an ectopic pregnancy the fertilised egg becomes an embryo and is implanted outside of the uterus. Most cases of extrauterine pregnancies happen in the fallopian tube (98%) but the embryo can fix itself on the cervix, ovary, abdomen, liver, spleen or caesarean section scar as well. As the embryo is implanted outside the uterus, it does not have the suitable environment for growing and developing, therefore the process of transforming into a fetus stops.

Ectopic pregnancy is a common cause of sickness and death in fertile women in the first trimester of pregnancy. In developed countries around 1-2% of pregnancies are ectopic, while in developing ones it is supposed to be a higher percent. In the developing world 1 in 10 patients with ectopic pregnancy ultimately dies from this condition because of the lack of proper medical services, leading to late diagnosis. Therefore, 10% of women diagnosed with ectopic pregnancy end up dying because of it. The most frequent causes of death related to ectopic pregnancy are hemorrhage, infection and anesthetic complications.


Symptoms of an ectopic pregnancy are usually pelvic pain and vaginal bleeding in the gestational period of 6 to 10 weeks. Unfortunately, these are also normal symptoms during pregnancy so it is hard to diagnose based only on these signs. Other symptoms include: shoulder tip pain, syncope (fainting) or abdominal tenderness (pain when pressing on the abdomen).

One third of patients have no clinical signs (signs observed by the doctor) and 9% of them have no symptoms (patients feel good). Some cases of ectopic pregnancies can even mimic other conditions such as appendicitis, gastrointestinal or urinary tract diseases, urinary tract infection or misscariage, making the diagnosys very difficult.

Risk factors

The exact cause of ectopic pregnancies is not completely elucidated, but in the last decades the incidence of ectopic pregnancies has risen, due to several factors: an increase in risk factors, the increased use of ART (assisted reproductive technology) and increased awareness, as a result of medicine evolving. Unfortunately, around 50% of women with this condition do not have an identifiable risk.

The major risks that can cause ectopic pregnancy are: damage of the fallopian tube as a result of surgery or infection with Chlamydia trachomatis, smoking or IVF (in vitro fertilization).

Risk factors:

  1. Damage of the fallopian tube

  2. Previous pelvic or abdominal surgery

  3. Previous pelvic infection: infection with Chlamydia trachomatis has been linked with 30-50% of all ectopic pregnancies. The mechanism is still unknown, but it is claimed that the infection and recurrent infections cause tubal inflammation and tubal damage over time. Another infection that can cause ectopic pregnancy is caused by Neisseria gonorrhoeae.

  4. Assisted reproduction technology (ART): in vitro fertilisation has an 2-5% chance of developing into an ectopic pregnancy. The first IVF pregnancy, that was unsuccessful, was an ectopic one. The risk of developing an ectopic pregnancy increases with the number of embryos transferred during IVF treatment. Women who undergo IVF because of infertility related to fallopian tube damage, are more prone to developing ectopic pregnancies than women that approach this method because of male infertility.