Exploring the presence of markers of decidualisation in the fallopian tubes: a systematic review

The Fallopian tubes (FTs) are part of the female upper genital tract. The healthy FT provides the biological environment for successful fertilisation and facilitates the subsequent movement of the conceptus to the endometrial cavity. However, when the FT is damaged, as with salpingitis, pyosalpinx and hydrosalpinx, it may increase the risk of an ectopic pregnancy, a life-threatening condition. Decidualisation refers to a multifactorial process by which the endometrium changes to permit blastocyst implantation. The decidualisation reaction is vital for endometrial receptivity during the window of implantation. To date, no comprehensive review that collates evidence on decidualisation in the human FT has been conducted. Therefore, the aim of this review is to compile the current evidence on cellular decidualisation occurring in the healthy and pathological FT in women of reproductive age. A literature search was conducted using five databases and identified 746 articles, 24 of which were analysed based on inclusion and exclusion criteria. The available evidence indicates that the FT are able to undergo decidual changes under specific circumstances, however, the exact mechanism by which this occurs is poorly understood. Further research is needed to elucidate the mechanism by which decidualisation can occur in the FT.