Lower pregnancy rate in women with high uterine peristalsis before embryo transfer: a systematic review and meta-analysis

Uterine activity, also known as peristalsis, is particularly important during the embryo implantation phase of fertility treatment. However, despite previous studies, most clinicians have not paid sufficient attention to uterine peristalsis. Recent studies have recognised its importance and evaluated contractility parameters prior to embryo transfer.

A systematic literature search was conducted in Medline, Embase and Cochrane up to January 2024. Inclusion criteria were studies involving patients undergoing in vitro fertilization treatment in which uterine contractility was assessed. Studies were excluded if they included therapeutic interventions that affected contractility, or if they focused on uterine pathologies such as adenomyosis or fibroids. The meta-analysis included trials that compared clinical pregnancy rates in women with high versus low uterine peristalsis.

A total of 2634 women were included in the systematic review, of whom 1134 (43.1%) underwent embryo transfer and were eligible for meta-analysis. Women with more than two uterine contractions (UC)/min had a significantly lower clinical pregnancy rate compared with women with lower uterine contractility (OR 52, 95% CI: 0.38- 0.69).There was moderate heterogeneity between studies (I2 = 55, p < 0.01).

Our study shows lower clinical pregnancy rates in women with high uterine contractility, highlighting the vital role of uterine peristalsis during embryo implantation. Therefore, reducing uterine activity prior to embryo transfer may potentially improve pregnancy rates. However, due to the limited and heterogeneous data available, the influence of uterine peristalsis on reproductive outcomes, including live birth rates, remains unclear. Publication History Article published online: 01 October 2024 © 2024. Thieme. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany