Ectopic Pregnancy

Ectopic pregnancy is  defined as a “developing embryo implanting at a site other than the cavity of  the uterus”.  The embryo may attach to  any surface within the abdomen or pelvic cavity.  98% of the time that surface is within the  fallopian tube.  This is sometimes called  a tubal pregnancy.  Rarely, the  developing embryo may attach to another site such as the cervix, ovary or  within the join between the fallopian tube and uterus.  This is called an interstitial or cornual  pregnancy.  Rarely, a so-called  heterotopic pregnancy may occur, where a twin pregnancy, implants one within  the fallopian tube and one within the endometrial or uterine cavity.  This is more common after a double embryo  transfer, in women undergoing infertility treatment.

Why is ectopic pregnancy dangerous?

Embryos that do not  implant in the uterine wall are unable to develop normally ad cannot end in a  healthy term pregnancy. Usually the embryo has already stopped developing at  the time of diagnosis. Unfortunately an ectopic pregnancy cannot Ectopic  pregnancies may cause rupture of the organ in which they are implanted,  typically the fallopian tubes.  This  generally leads to slow, prolonged bleeding although in some situations may  cause rapid bleeding.  Rapid blood loss  such as this has resulted in maternal death.   This still happens but is very unlikely as ectopic pregnancies are  nowadays diagnosed much earlier and treated expeditiously.

What causes ectopic pregnancy?

The following factors have been identified  as causes of ectopic pregnancy.   Sometimes more than one, or none, may apply:

1. Abnormalities of the fallopian tubes. If the fallopian tubes are damaged or abnormal as a result of previous infection (typically pelvic inflammatory disease) endometriosis, surgery, tumours or rarely due to malformations present since birth there is an increased risk of ectopic pregnancy. Surgery to reconstruct the fallopian tubes after tubal ligation can also increase the risk of ectopic pregnancy.  The previous infection concerned, may not have been noticed by the patient.
2. Previous ectopic pregnancies.  The base line risk of ectopic pregnancy is around 1:100 however this increases to 1:10 if a previous ectopic pregnancy has been diagnosed.
3. Previous genital or pelvic infections.  Pelvic infections, Gonorrhea or Chlamydia are a major cause of tubal problems, scarring and adhesions, which increase the risk of ectopic pregnancy.  Note that conditions such as appendicitis and endometriosis can do likewise.
4. The incidence of ectopic pregnancy high in women with infertility most likely due to an increased incidence of tubal abnormalities. Fertility drugs may also increase the risk in this population.
5. Multiple sexual partners. Having more than one sexual partner is associated with an increased risk of pelvic infection and therefore an increased risk of ectopic pregnancy.
6. IVF treatment (in vitro fertilization).  This is associated with both an increased risk of ectopic and heterotopic pregnancy.
7. Tubal ligation.  Tubal ligation is a surgical procedure in which the fallopian tubes have been cut, clamped or burnt in order to prevent further pregnancies.  Since the tube is made of living tissue, sometimes a tiny hole occurs adjacent to the point of occlusion, which means that a pregnancy is possible.  A pregnancy in this case, is commonly within the fallopian tube hence an ectopic pregnancy.  The risk of an ectopic pregnancy after tubal ligation does not decrease with a period of time.
8. Intrauterine contraception devices.. Women who become pregnant whilst using an IUD have a slightly higher risk of ectopic pregnancy. This means not that ectopic pregnancies are more common however a greater proportion of pregnancies are ectopic in this situation.
9. Smoking

Ectopic pregnancy symptoms:  How might I know that I have an ectopic?

The most common  symptoms of ectopic pregnancy include, abdominal pain, a missed or altered last  period, vaginal bleeding which may be minimal in combination with symptoms of  early pregnancy such as breast tenderness, frequent urination or nausea.

In days gone by  ectopic pregnancies more frequently presented after collapse of the patient due  to blood loss, but thankfully this is now rare. The most common symptoms are  slight abdominal pain, an abnormal period, and a slowly rising beta hCG,  (pregnancy hormone.)  Around 50% of women  have no symptoms until the fallopian tubes bleeds.

What are the consequences of ectopic pregnancy?

Ectopic pregnancies  can sometimes resolve on their own, however, the consequence of an ectopic not  resolving and progressing to rupture or intra abdominal bleeding is so severe  that waiting for an ectopic pregnancy to resolve is not recommended  treatment.  As soon as an ectopic  pregnancy is diagnosed it should be treated.

Ectopic pregnancy diagnosis

Ectopic pregnancy can  be difficult to diagnose.  Sometimes,  they form when the pregnancy is so early that they cannot be seen on an  ultrasound.  However a combination of  Beta hCG, blood tests, ultrasound and examination are helpful.  Sometimes a laparoscopy is required to  diagnose an ectopic pregnancy.

Ectopic pregnancy treatment

An ectopic pregnancy  must be treated in order to stop its growth and prevent complications.  Treatment is broadly divided into medical  treatment and surgical treatment.

1. Medical  treatment

Methotrexate is a  very successful treatment for ectopic pregnancy.  It you use Methotrexate an ectopic pregnancy  must fulfil several criteria, which I will explain to you.  Therefore Methotrexate is not appropriate in  all the patients.  However it can be a  useful way of causing an ectopic pregnancy to resolve without surgery.

2. Surgical  management

Surgery is still the  mainstay for treatment of ectopic pregnancies.   This should invariably be done via a laparoscope.  A skilled surgeon can deal with even a  ruptured ectopic pregnancy, where there is a lot of intra abdominal blood,  laparoscopically.  It should rarely or  never be needed to perform a laparotomy on someone with an ectopic pregnancy.  Sometimes, Methotrexate treatment may fail,  resulting in subsequent surgical treatment.   It is important to realize, that this is not so much a failure of  treatment or reflecting a poor treatment choice however this reflects  appropriate judgment when the desired response to Methotrexate is not  gained.

Will my fallopian tube be removed?

During surgery it is  sometimes possible to remove an ectopic pregnancy from the tube (called salpingostomy) It is nice to perform this if the woman would like to become  pregnant in the future, however this is not always possible as the tube is  usually extensively damaged by the ectopic pregnancy.  In most cases, mainstream management is  removal of the fallopian tube.  It is important  to remember, that a fallopian tube affected by an ectopic pregnancy, is rarely  of use in the future and will probably cause further ectopic pregnancies on  that side.

Consequences of removing a fallopian tube

Surprisingly, removal  of a single fallopian tube does not greatly decrease fertility.  I am often asked if it means a woman can only  fall pregnant every second month, however the fallopian tube on the opposite  side is easily able to reach across the pelvis to pick up eggs from the other  ovary.  When the ectopic pregnancy is  diagnosed and removed surgically, the ovary of the same side is left  intact.  It is surprising, that in around  10-20% of cases, one sees an ovarian cyst, from which the lady ovulated in  order to form the pregnancy on the opposite side to the ectopic pregnancy proving  this point.

Hospital stay

Duration of the  hospital stay often reflects the pre operative state in which the woman arrives  in theatre.  If she has been sick or  presented to hospital acutely unwell, then although the laparoscopic surgery  for treatment for ectopic pregnancy is very simple, an overnight stay might be  required.

Sometimes  a blood transfusion is required after the operation or during an anaesthetic  however this is unlikely.