Endometrial perfusion across the normal human menstrual cycle assessed by laser Doppler fluxmetry

Abstract

This study investigated variations in microvascular perfusion of human endometrium across the menstrual cycle, using a laser Doppler technique to assess red blood cell (RBC) flux. Endometrial RBC flux was monitored by laser Doppler fluxmetry via a fibre optic probe inserted transvaginally into the uteri of 19 conscious normal volunteer women, on four occasions at weekly intervals over one menstrual cycle. Regional variation in RBC flux was investigated in 16 surgical patients under general anaesthesia and in five excised uteri. Endometrial perfusion exhibited short-term temporal variations consistent with the cardiac cycle and often also showed vasomotion (5-12 cycles/min). Mean endometrial perfusion differed between phases of the menstrual cycle in conscious women, being highest during early proliferative and early follicular phases. There were no significant regional differences in local mean endometrial perfusion in anaesthetized patients. No evidence of endometrial ischaemia/reperfusion episodes was found in any subject using this technique. This study provides benchmark data of variations in RBC flux per unit volume of tissue in the luminal approximately 1 mm of endometrium, across the normal human menstrual cycle. Flux values were highest at times associated with endometrial growth and preparation for implantation, indicating that RBC flux may be a useful parameter for assessment of endometrial physiology.

The human corpus luteum: life cycle and function in natural cycles

“…Steer et al (115) reported that the chance of pregnancy was maximal when the uterine pulsatility index (PI) was in the range of 2.00 to 2.99. Subsequently, Gannon et al (116) used an intrauterine laser Doppler technique to measure endometrial microvascular blood flow, which varied throughout the menstrual cycle, with increases in blood flow during the early follicular and early luteal phases.…”

Regulation of endometrial vascular remodelling: role of the vascular endothelial growth factor family and the angiopoietin–TIE signalling system

“…Peri-menstruation, no significant changes in blood flow were observed and no ischaemia/reperfusion episodes have been detected (Fraser & Peek 1992). Only very low levels of hypoxia-inducible factor 1 a (HIF1A) and HIF2A, early markers of hypoxia, have been observed in the human endometrium (Gannon et al 1997). An alternative theory to vasoconstriction and hypoxia suggests that menstruation is an inflammatorytype process (Salamonsen 2003).…”

Recent advances in endometrial angiogenesis research

“…Overall blood flow in the endometrium was not significantly reduced peri-menstrually [87] and no endometrial ischaemia/reperfusion episodes have been detected peri-menstrually by a Doppler technique [88]. In addition, only very low levels of the early markers of hypoxia HIF-1a and HIF-2a have been observed in the human endometrium [89].…”