Comparison of endometrial and subendometrial blood flow measured by three-dimensional power Doppler ultrasound between stimulated and natural cycles in the same patients.
BACKGROUND
Low implantation rates in stimulated IVF cycles may be related to suboptimal endometrial perfusion. Endometrial and subendometrial blood flow was compared between stimulated and natural cycles in the same patients undergoing IVF.


METHODS
Three-dimensional (3D) ultrasound examination with power Doppler was performed in stimulated and natural cycles of 67 consecutive patients to measure endometrial thickness, uterine artery pulsatility index/resistance index, endometrial volume, vascularization index (VI)/flow index (FI)/vascularization flow index (VFI) of endometrial and subendometrial regions.


RESULTS
Endometrial and subendometrial blood flow was absent in four (6.0%) patients in the stimulated cycle and two (3.0%) patients in the natural cycle. Endometrial and subendometrial VI/FI/VFI were significantly lower in stimulated cycles than those in natural cycles. The median (95% CI) decreases in endometrial VI/FI/VFI were 35.8% (-2.5, 216.8), 5.0% (0.1, 12.3) and 48.4% (2.5, 315.3) respectively whereas the corresponding decreases in the subendometrial region were 66.6% (-0.2, 220.5), 4.3% (0.8, 16.2) and 76.3% (41.0, 303.4) respectively.


CONCLUSIONS
Endometrial and subendometrial blood flow was significantly lower in the stimulated cycle than that in the natural cycle.
Ng
Ernest Hung Yu
EH
Department of Obstetrics and Gynaecology, The University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China. nghye@hkucc.hku.hk
Chan
Carina Chi Wai
CC
Tang
Oi Shan
OS
Yeung
William Shu Biu
WS
Ho
Pak Chung
PC
D000328:Adult; D001158:Arteries / Q000000981:diagnostic imaging; D001808:Blood Vessels / Q000000981:diagnostic imaging; D004717:Endometrium / Q000098:blood supply* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007247:Infertility, Female / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D010062:Ovulation Induction; D011674:Pulse; D012039:Regional Blood Flow; D018608:Ultrasonography, Doppler; D014599:Uterus / Q000098:blood supply; D014655:Vascular Resistance