In a new study, researchers at the University of Edinburgh concluded that female smokers who’ve experienced an ectopic pregnancy have raised levels of the protein PROKR1 in their fallopian tubes.
Ectopic pregnancies occur when a fertilised egg becomes implanted outside the womb, usually in the fallopian tubes.
The increased presence of PROKR1 is thought to hinder the transfer of eggs to the uterus by preventing the muscles in the fallopian tube walls from contracting.
According to the scientists, a chemical in cigarette smoke called cotinine is responsible for the harmful levels of the protein.
‘This research provides scientific evidence so that we can understand why women who smoke are more at risk of ectopic pregnancies and how smoking impacts on reproductive health,’ said Dr Andrew Horne, from the university’s Centre for Reproductive Biology.
‘While it may be easy to understand why inhalation of smoke affects the lungs, this shows that components of cigarette smoke also enter the bloodstream and affect seemingly unconnected parts of the body like the reproductive tract.’
It’s thought that smoking increases the risk of ectopic pregnancy by up to four times, with the egg implanting itself in the fallopian tube instead of the womb in 98 per cent of cases.
This can cause the tube to rupture and affect a woman’s ability to conceive in future.
Metro UK