Aim. The objective of the present study was to evaluate the influence of normal cyclic fluctuations of the hormonal status in the women of the reproductive age on the state of the great saphenous vein. Material and methods. The study included 25 nulliparous women of the reproductive age having no complaints as regards venous problems in the absence of instrumentally detectable signs of vascular lesions in the lower extremities. All the participants of the study underwent ultrasound and photopletythmographic examination of the venous system in the lower extremities during different phases of the menstrual cycle. Results. Transient reflux in the end of the luteal phase of the menstrual cycle was detected in 54% of the examined great saphenous veins that were characterized by the deteriorated elastic/resilient properties as it was apparent from the significant reduction of the venous refilling time assessed by photopletythmography. Conclusion. The maximum level of endogenous progesterone in the end of the luteal phase of the menstrual cycle is associated with the deterioration of the elastic/resilient properties of the venous walls and the development of transient blood reflux that disappears during the follicular phase. It is concluded that the possibility of transient venous reflux in the women should be taken into consideration when planning and implementing diagnostic and therapeutic measures.