Circadian changes in uterine artery and ovarian stromal blood flow after pituitary down-regulation.
OBJECTIVE
To investigate changes in the uterine artery and ovarian stromal blood flow in relation to the time of the day after pituitary down-regulation during in vitro fertilization treatment.


METHODS
Thirteen women were recruited. The uterine artery blood flow was studied using pulsed color Doppler ultrasonography and the ovarian stromal blood flow was measured using three-dimensional power Doppler ultrasonography. Ultrasound scan examinations and blood pressure measurements were performed in the morning and evening.


RESULTS
The diastolic and the mean arterial pressures were significantly higher in the evening. An increase in the uterine artery pulsatility index and resistance index in the evening was observed. The ovarian vascularization index, vascularization flow index, and right ovarian flow index were significantly lower in the evening.


CONCLUSIONS
Despite the small sample size, we have demonstrated the presence of a diurnal change in uterine artery and ovarian stromal blood flow after pituitary down-regulation. Such changes may be related to the systemic change in the sympathetic system and hence vascular resistance. Future study regarding ovarian stromal blood flow should take into account the effect of the time of the day on the readings in order to avoid misleading interpretation of data.
Department of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, SAR. cwcchan@graduate.hku.hk
Carina C W
CC
Chan
Ernest H Y
EH
Ng
Oi-Shan
OS
Tang
Pak-Chung
PC
Ho
D000328:Adult; D002940:Circadian Rhythm; D015536:Down-Regulation; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D010053:Ovary / Q000098:blood supply* / Q000166:cytology; D010902:Pituitary Gland / Q000502:physiology*; D012039:Regional Blood Flow; D018615:Ultrasonography, Doppler, Color; D018617:Ultrasonography, Doppler, Pulsed; D014599:Uterus / Q000098:blood supply*