Impact of intramural leiomyomata on in-vitro fertilization-embryo transfer cycle outcome

Purpose of review The effect of leiomyomata on implantation and pregnancy rates resulting from in-vitro fertilization-embryo transfer has not been clearly defined. Submucosal and intramural leiomyomata which distort the endometrial cavity clearly affect outcome. However, the impact and possible mechanism of action of intramural lesions, which do not clearly alter the contour of the endometrial cavity, remain controversial. This review evaluates recent literature addressing these issues. Recent findings Several recent studies have evaluated the impact of leiomyomata on the uterine environment. Alterations in uterine artery blood flow may have an impact on implantation, although conflicting results have been reported. Other recent studies have evaluated alterations in gene expression and local cytokine release which may also play a role. Five recently published clinical case-controlled trials provide conflicting information regarding the impact of these lesions on in-vitro fertilization-embryo transfer cycle outcome as measured by clinical pregnancy and implantation rates. Results varied from no effect to a highly significant and deleterious impact on cycle outcomes. These differences may be partly attributable to differences in patient inclusion criteria and inconsistencies in analyses of precise fibroid location and size. Summary Intramural leiomyomata, which impinge upon the uterine cavity, negatively affect in-vitro fertilization-embryo transfer cycle outcome. Myomectomy should be beneficial in these circumstances despite an absence of data in this regard. No definitive statements can be made regarding intramural leiomyomata, which do not distort the cavity due to differing outcomes from currently available investigations. In the absence of more clear cut data, no recommendation can be made to support routine myomectomy in these cases. Rather, clinical management should be individualized.