Background: Uterine contractility, also known as uterine peristalsis (UP), is a critical determinant of fertility, affecting sperm transport and embryo implantation. Increased uterine peristaltic activity has been associated with reduced pregnancy rates. However, data are heterogeneous and uterine contractility has not been widely translated into clinical practice. Cine-MRI, although limited by cost and heterogeneity in data reporting, has emerged as a promising tool to assess uterine dynamics and increase our knowledge of UP in physiological and pathological conditions. Objective: This systematic review and meta-analysis aimed to describe patterns of UP in physiological and pathological uterine conditions, including endometriosis and fibroids, using cine-MRI. Methods: A systematic literature search of the Medline, Embase, Cochrane and CENTRAL databases and Google Scholar was conducted up to May 2024, including studies evaluating UP by cine-MRI. Clinical studies evaluating uterine contractility were included, excluding those affected by therapeutic interventions or unrelated pathologies. This meta-analysis pooled data from studies comparing uterine contractility in patients with endometriosis. Results: In the 13 included studies (365 women), uterine contractility varied significantly according to menstrual cycle phases and pathological conditions. This meta-analysis showed that women with endometriosis had higher uterine contractility in the luteal phase (0.74; 95% CI: 0.27-1.21) but not in the periovulatory phase (SMD 0.8; 95% CI: -3.78-5.37). Conclusions: Cine-MRI is a promising diagnostic tool for the analysis of UP. Endometriosis is associated with impaired UP, which may be a cause of the decreased implantation rate and infertility in endometriosis. However, further research is needed to consolidate the effect of UP on implantation and fertility and to develop standardised and cost-effective tools to assess uterine contractility and tailor infertility treatment.
Keywords: MRI-cine; endometriosis; fertility; infertility; uterine contractility; uterine peristalsis.