We believe that pregnancies implant in the Fallopian tube because of a combination of factors: a failure of the mechanisms which move the pregnancy along the Fallopian tube into the womb and a change in the environment in the Fallopian tube that allows early implantation to occur.
We also know that some things make you more at risk of having an ectopic pregnancy. If you’ve had previous abdominal surgery (for example, your appendix removed or a caesarean section) your risk is said to be increased up to 4 times. If you’ve had a sexually transmitted infection like Chlamydia, then your risk is increased up to 2 and 3 times. If you’re a smoker again your risk is increased between 2 and 3 times. And interestingly, if you’ve had fertility treatment, such as IVF, then your risk is increased as well.
How these risk factors cause ectopic pregnancy is something that we don’t really understand, but we’ve been doing research on this in Edinburgh.
See link: www.ectopic.org.uk/index.php/press/press-releases.