Reasons for an ectopic pregnancy

Any sexually active woman of childbearing age is at risk of an ectopic pregnancy and often the reason for the ectopic pregnancy will never be determined. However, ectopic pregnancies are more likely if you have had:

  • Previous ectopic pregnancy
    There is an increased risk of a subsequent ectopic pregnancy after someone has experienced an ectopic pregnancy.
  • Fertility Treatment
    There is a chance of ectopic pregnancy resulting from embryo transfer during IVF treatment as embryos can travel into the Fallopian tube, for example, during the implantation stage.
  • Older age
    There is an increased risk of ectopic pregnancy for older women.
  • Pelvic Inflammatory Disease
    This is a past infection of the Fallopian tubes caused, for example, by a sexually transmitted infection like Chlamydia trachomatis.
  • Tubal Surgery
    An operation on the Fallopian tubes, such as sterilisation.
  • Endometriosis
    This is a condition where cells like the ones lining the womb grow elsewhere in the body but still react to the menstrual cycle each month and bleed despite there being no way for the blood to leave the body. It is not known why endometriosis increases your risk of ectopic pregnancy.
  • Abdominal Surgery
    Any previous operation on the tummy, such as caesarean section, appendicectomy
  • A copper contraceptive coil (IUCD)
    The coil prevents a pregnancy in the uterus but is less effective in preventing a pregnancy in the Fallopian tube.
  • The ‘mini-pill’ (progesterone-only pill)
    This type of contraceptive pill alters the ‘motility’ of the tube i.e. the ability for an egg to move through it.
  • The Morning After Pill
    It is possible to become pregnant in the same cycle after trying to prevent pregnancy with emergency oral contraception.
  • Cigarette Smoking
    Research by the University of Edinburgh showed that smokers have an increased level of the protein PROKR1 in their Fallopian tubes. The protein is instrumental in helping pregnancies implant in the womb, but when present in the Fallopian tubes can hinder the progress of a fertilised egg, increasing the chances of a pregnancy being ectopic.
  • Diethylstilbestrol (DES)
    This was a synthetic oestrogen given to women with a history or risk of miscarriage in the 1950’s to 1970’s. Unfortunately, in some cases, the medicine resulted in the reproductive organs of the fetus not forming properly. If your mother took this medicine then it may have contributed to changes in the way your reproductive organs developed. However, doctors can usually see this when performing an ultrasound scan or when you are treated with surgery. Any changes in your reproductive organs as a result of DES are unlikely to go unnoticed.

It is important to remember that the ectopic pregnancy was not your fault and that there was nothing you could have done to prevent it happening.

The following commonly asked reasons are NOT causes of ectopic pregnancy:

  • Ectopic pregnancy is not hereditary
    i.e. it is not a condition that passes from parent to offspring. You are no more at risk of an ectopic pregnancy than anyone else, even if your immediate family members suffered.
  • Miscarriage is not related to ectopic pregnancy
    Unfortunately, miscarriage is a very common event that occurs in one in five first trimester (first 12 weeks) pregnancies but there is no link between the two conditions.
  • Abortion is not linked to ectopic pregnancy
    The decision to terminate pregnancy is a big decision based on the circumstances at the time and, if in those precise circumstances again back where the decision was being made, or in some cases having the decision made for us, then many of us would probably make the same decision over and over again. There are many inaccurate research articles online, often used as propaganda by pro-life groups, making tenuous links between termination and ectopic pregnancy. There is nothing at all, however, to be gained by frightening ourselves about a termination and whether it might or might not have contributed to a subsequent loss. We would ask anyone struggling with this issue to please be gentle with yourselves and don’t believe everything you read on the web, in the news, or in magazines. Always check the source of the figures that are quoted. Most of all, don’t beat yourselves up for something that cannot be changed and is unlikely to have contributed anyway.
  • Exercise and sport in general
    Including intense exercise like spinning, makes no contribution to ectopic pregnancy.
  • There is no evidence at all to link ectopic pregnancy to flying
    But you should not fly if you have or might be having an ectopic pregnancy.