The success rates for treatment with in-vitro-fertilisation (IVF) can be described as no more than reasonable. A constant search for ways to improve these results is going on. One possible way has come from an unexpected source, by scratching the lining of the womb (uterus). This is performed in a painless procedure using a thin plastic device (Pipelle) which is normally used for taking a biopsy of the uterine lining (endometrium). The best time to do this is apparently once in the latter half of the cycle preceding the IVF treatment cycle. One ‘scrape’ on each of the four surfaces of the uterus (back, front and both sides), by passing the instrument through the neck of the womb seems to be enough to do the trick. Most of the research has been performed on women who have failed to conceive in one or more of their previous cycles and the results so far have been very encouraging in producing pregnancies in those whose previous treatment has failed.
While the improvement in pregnancy rate by endometrial scratching is become clearer with each piece of research published, the way it works remains a mystery. The mechanism by which an embryo implants and starts to grow in the uterus is immensely complicated by the number of factors involved, both from the side of the embryo and from the endometrium. These range from factors which encourage the penetration of the embryo into the uterine lining, deal with nourishment, increase blood supply and ensure that the embryo will not be rejected as a ‘foreign body’. Whatever the mechanism, now being vigorously investigated, endometrial scratching may be a small step forward to improve the outlook for infertile couples undergoing IVF.