Relationship of thyroid blood flow to reproductive events in normal Chinese females

The purpose of this study was to investigate the blood flow characteristics in the superior thyroid artery (STA) in normal females of prepubertal, rep roductive, and postmenopausal age. The study was performed in 29 prepuberta l girls, 27 females of reproductive age, and 26 postmenopausal women. The p eak systolic velocity (PSV) and the pulsatility index (PI) of the STA were measured repeatedly during one menstrual cycle in females of reproductive a ge, and measured once in each prepubertal and postmenopausal subject. Diffe rent waveforms were observed in females of prepubertal, reproductive, and p ostmenopausal age, The PSV of the STA increased progressively in females fr om prepubertal to postmenopausal phases. The PI of the STA in all of the pr epubertal girls was lower than that of adult females in different phases of the menstrual cycle, In adult females, the PI in the follicular phase was significantly higher than those in the ovulatory and luteal phases, In all of the postmenopausal women, the PI was comparable to that in older prepube rtal subjects and in adult females during the ovulatory and luteal phases, The results suggest that oestrogen may affect thyroid blood flow during the normal menstrual cycle, Growth and progressive change of arterial structur e are suggested to affect the thyroid blood Bow in prepubertal and postmeno pausal states. (C) 1999 World Federation for Ultrasound in Medicine & Biolo gy.