Uterine contractility during the menstrual cycle

Abstract

The non-pregnant uterus shows different patterns of contractility during the menstrual cycle. A renewed interest in uterine contractility has resulted from reports of non-invasive ultrasound (US) based studies. To clarify the changes in uterine contractility occurring throughout the menstrual cycle, we prospectively studied uterine contractions (UC) at six representative stages with US and intrauterine pressure (IUP) based approaches in 30 cycling volunteers. Results showed UC frequency could be measured by either US or IUP. UC amplitude and resting pressure tone could only be assessed by IUP. Conversely, direction of UC displacement could only be assessed by US. UC frequency increased at mid-cycle and decreased throughout the luteal phase suggesting oestradiol and progesterone exert positive and negative actions on uterine contractility, respectively. UC amplitude increased throughout the menstrual cycle to maximum values in the late luteal phase. Retrograde UC were most frequent at mid-cycle and convergent ('opposing') UC predominated during the luteal phase. While the former pattern ensures sperm transport, the latter may facilitate embryo implantation. In conclusion, UC changes throughout the menstrual cycle assessed by US and IUP emphasize the hormonal dependence of uterine contractility. Although UC patterns favouring sperm transport appear regulated by oestradiol, uterine quiescence and the dominance of convergent UC prevailing at the time of implantation are linked to progesterone. These data will serve to identify and treat possible dyskinetic changes in uterine contractility, particularly in women suffering from infertility, endometriosis, and dysmenorrhea.

A new method for analysis of non‐pregnant uterine peristalsis using transvaginal ultrasound

“…The maximum amplitudes of transverse cavity centerline movement were 0.5-1.5 mm with a mean ± SD of 0.94 ± 0.34 mm. 7 Proliferative TVS 0.6-5.4 Bulletti et al 12 Proliferative: Catheter + TVS late follicular 2.70 ± 0.6 periovulatory 3.50 ± 0.6 Nakai et al 13 Proliferative MRI 2.82 Present study Proliferative and early secretory TVS 2.94 ± 0.6 *Data given as range, mean or mean ± SD. MRI, magnetic resonance imaging; TVS, transvaginal sonography.…”

“…This study included 18 healthy non-pregnant women aged 28-41 years (12 of whom were 35 years or older) who had anatomically normal uteri and were in the proliferative (15 women at days [10][11][12][13][14] or early secretory (three women at days 15-18) phase of their menstrual cycle. The study was approved by the hospital ethics committee and all women gave written informed consent to participate.…”

Three‐dimensional fiber architecture of the nonpregnant human uterus determined ex vivo using magnetic resonance diffusion tensor imaging

“…The uterus, unlike the brain, for instance, undergoes constant small movements due to normal breathing and spontaneous uterine contractions (Bulletti et al, 2000). Because these effects can lead to poor MR measurements using DTI, data were obtained from five ex vivo organs of patients aged between 34 and 61 years subjected to hysterectomy for medical reasons.…”

‘Venous lakes’ — a corrosion cast scanning electron microscopy study of regular and myomatous human uterine blood vessels

“…Buletti et al [7] injected specimens with coloured latex and noted that venous vessels can form large dilatations -the so called 'venous lakes'. He found that they are more numerous at early and midluteal phases.…”

“…Bulletti et al [7] stated that the most important morphological changes occur on spiral and arcuate arteries, as well as on venous lakes. Further data on the morphology and variations of the venous lakes, using SEM, should be acquired.…”