What is an ectopic pregnancy?

Ectopic pregnancy can be quite serious, even life-threatening, for the mother. But women who experience it can go on to subsequently have a healthy pregnancy and birth, says Dr Howard Lee

The word 'ectopic' means out of place, and so, an ectopic pregnancy is one where the fertilised egg attaches itself somewhere outside the cavity of the uterus (the womb). It can develop in the ovary, the abdominal lining, or even the cervix (neck of the womb), but the most common place - 96% of all ectopics - is somewhere in the fallopian tube.

When you realise that the female egg leaves the ovary and finds its way into the open end of the fallopian tube, in order to start its journey towards the cavity of the uterus, and that fertilisation occurs somewhere along this route, it is surprising that - in the UK - only 1 in 150 pregnancies will result in an ectopic development. Ectopic pregnancies are becoming more common due to the increase in sexually transmitted infections such as chlamydia and gonorrhea which, if untreated, can block or twist the fallopian tubes.

An ectopic pregnancy cannot survive

An ectopic pregnancy can occur anytime between the 4th and 10th week of pregnancy. In many cases the embryo stops developing and a spontaneous miscarriage occurs before about eight weeks. If this doesn't happen and the pregnancy continues to develop, the ectopic pregnancy causes pain and bleeding. If it is not treated quickly its increasing size can rupture the narrow fallopian tube and cause abdominal bleeding. The consequences, if this happens, are life-threatening.

What are the causes of an ectopic pregnancy?

There are many factors that increase the risk of an ectopic pregnancy, and they involve infection or injury that has altered the normal and highly complex function of the fallopian tubes.

  • Pelvic inflammatory disease - untreated infection can contort, scar or block the tubes.
  • Appenticitis and peritonitis where the appendix bursts can cause adhesions or scarring
  • Tubal surgery - any previous operation on the fallopian tubes - such as sterilisation and its reversal - makes an ectopic pregnancy more likely.
  • Previous ectopic pregnancy - it is a sad fact that up to 20 per cent of the pregnancies that follow an ectopic will themselves become ectopic.
  • Previous termination of pregnancy - increased risk of ectopic pregnancy among women who have had pregnancies terminated, especially if there has been an associated infection.
  • IVF and fertility drugs - where the ovaries are being stimulated by a fertility drug, or where a test-tube fertilisation technique is being used to help an infertile couple, there is an increased risk that any resulting pregnancy will be ectopic.
  • Advancing age - ectopic pregnancies are more common in the older woman.
  • Intra-uterine contraceptive coil - if this method fails to prevent a pregnancy, there is a slightly increased risk of it being ectopic.
  • Often, none of these increased risk factors can be demonstrated.

    How an ectopic pregnancy happens

    • As an emergency - the woman might not even know she's pregnant, and none of the usual signs of nausea or breast tenderness will be apparent, but she'll feel unwell and may collapse suddenly, needing emergency admission to hospital.
    • Many women miss a period, have a positive pregnancy test, some lower abdominal pain, and some irregular vaginal bleeding - which may be red or brown. The woman may feel faint or generally unwell. This usually occurs around 6-10 weeks of pregnancy because the fallopian tube contracts in response to the stretching caused by the growing embryo. Bleeding will occur into the abdominal cavity if the tube ruptures and this will result in severe abdominal pain.
    What are the tests that help to diagnose an ectopic pregnancy?

    There are various tests, and the first of these is a pregnancy test itself. There are, nowadays, fairly sensitive urine tests available, which can give an answer quickly. This can be followed up by a blood test. Vaginal ultrasound scanning can demonstrate a normally positioned womb pregnancy and therefore exclude an ectopic pregnancy in a tube.

    Sometimes, because of the early stage of development, a pregnancy test may be positive but the position of the pregnancy cannot be seen with ultrasound scanning. In this case, a woman needs to be carefully monitored and this may mean staying in hospital. The changing blood levels of the pregnancy hormone are noted, and together with other features, can indicate a normal or an ectopic pregnancy growth. Sometimes women have a laparoscopic examination (where a small telescope tube is placed into the abdomen). This will then give a definitive diagnosis.

    What treatments are possible?

    Once an ectopic pregnancy is diagnosed, there are several different treatments possible -unfortunately, these do not include the transplantation of this pregnancy into the womb.

    • A small number of ectopics do not cause the fallopian to rupture because the development stops and a miscarriage occurs.
    • In a few other cases, an injection may be possible to shrink the ectopic pregnancy.
    • Laparoscopic surgery, where either the tube is opened, or the tube itself removed, may also be a possibility.
    • In most cases, open, lower abdominal surgery is performed in order to operate on the affected fallopian tube.

    Whenever possible, surgeons attempt to conserve both of the tubes as this does seem to improve the chances of a normal pregnancy next time. A young woman, with a normal second tube and no signs of previous infection or scarring - will have a lower chance of another ectopic. A woman who has had severe pelvic inflammation, with damage to the other tube, has a higher risk of another ectopic pregnancy.

    It is very upsetting for a couple, who have been excited by the prospect of a new baby, to discover that their pregnancy is ectopic,and to realise that it will never be able to develop into a live birth.

    Coping with this grief at a time when marked hormone changes are taking place makes it all the more difficult. Tears and great emotional stress follow an ectopic pregnancy, along with quite unfounded feelings of guilt. Do ask for help or counselling or you can talk to other couples on our Coping with Miscarriage board (LINK). You can also contact The Miscarriage Association who have support groups across the country, and have more information about ectopic pregnancies.

    It is a horrible experience to go through but do remember, at least 50% of woman will go on to have a successful pregnancy next time.