The influence of uterine abnormalities on uterine peristalsis in the non-pregnant uterus: A systematic review

Uterine peristalsis is the rhythmic wave-like motion of the subendometrial layer of the uterus. These contractions change throughout the menstrual cycle in terms of direction, frequency and amplitude, and can be analysed with various methods. Not much is known about uterine peristalsis in patients with uterine abnormalities. To that end, we decided to systematically review the available studies for evidence on the influence of uterine abnormalities, including leiomyomas, endometriosis, adenomyosis and congenital uterine anomalies, on uterine peristalsis. After a systematic search of relevant databases, sixteen eligible studies were included in this review; eight case-control studies and eight controlled prospective cohort studies. The sample sizes ranged from twelve to 205 participants. Various methods of analysing uterine contractions were used, including transvaginal ultrasound, hysterosalpingo-radionuclide scintigraphy, cine MRI and intrauterine pressure measurement. Studies varied in their design, uterine contraction measurement method and patient groups. Generally however, uterine abnormalities do seem to have an influence on uterine peristalsis. Compared to healthy controls, the specific phase of the menstrual cycle (namely the periovulatory and luteal phases) seems to play a major role in the observed effect on uterine contractions. The included studies were difficult to compare directly due to heterogeneity however, and sample sizes were relatively small. Despite these limitations, it can be concluded that uterine abnormalities likely have a menstrual phase-dependent effect on uterine peristalsis and contraction features. These aberrant contractions potentially play a role in the relationship between (benign) uterine abnormalities and infertility, along with other associated symptoms (i.e., dysmenorrhea, abnormal uterine bleeding). It is not yet possible to make a definite conclusion on the nature of this effect however. Further research is needed on objective measurement tools, treatment and clinical consequences of abnormal uterine peristalsis in patients with uterine abnormalities.