Uterine peristalsis

The non-pregnant uterus is characterized by spontaneous myometrial contractions, which are known as uterine peristalsis that have essential roles during early human reproduction. Uterine peristalsis is responsible for removal of menstrual debris, rapid transport of sperm through the female genital tract for fertilization to occur in the fallopian tube and transporting the embryo to a proper implantation site in the uterine wall. The spontaneous contractions were observed to propagate from the cervix to the fundus at a rate of 1–5 contractions per minute during the proliferative and secretory phases, with the direction being reversed and the contractions’ rate slowed to 0.5–2.5 contractions per minute during menstruation. The highest intrauterine pressures were observed during menstruation. We have developed objective computerized procedures for analysis of the dynamic characteristics of uterine peristalsis from transvaginal ultrasound (TVS) imaging. These methods are designed to evaluate the characteristics of intrauterine fluid and endometrium interface or the endometrium-myometriun interface (EMI). The EMI is visible in most cases during TVS, independent of the content within the uterine cavity. Moreover, the data can be computed at any specific distance from the fundus in the mid-sagittal cross-section, thus being capable of detecting local pathologies in this region. Recently, we modified the tracking procedures of the instantaneous EMI and apply the methodology of the active contours (snakes) model to study uterine peristalsis in abnormal uteri, for example, after Caesarean sections in women at fertile age as shown in the movie below with 4 panels.