Pathophysiologic features of "thin" endometrium.
OBJECTIVE
To characterize pathophysiologic features of a "thin" endometrium.


METHODS
A prospective observational study.


METHODS
University Hospital and City General Hospital.


METHODS
Patients with normal-thickness endometrium (Normal-Em group: endometrial thickness >or=8 mm; n = 57) and thin endometrium (Thin-Em group: endometrial thickness <8 mm; n = 17).


METHODS
Blood flow impedance of the uterine radial artery (RA) was assessed as resistance index (RI) by transvaginal color-pulsed Doppler ultrasonography. The area of glandular epithelium, the number of blood vessels, and vascular endothelial growth factor (VEGF) expression were examined in the midluteal-phase endometrium.


RESULTS
The RA-RI in the Thin-Em group was significantly higher than in the Normal-Em group throughout the menstrual cycle. Endometrial thickness was significantly correlated with RA-RI. Growth of glandular epithelium, the number of blood vessels, and VEGF expression were significantly lower in the Thin-Em group than in the Normal-Em group.


CONCLUSIONS
A "thin" endometrium was characterized by high blood flow impedance of RA, poor epithelial growth, decreased VEGF expression, and poor vascular development.
Miwa
Ichiro
I
Department of Obstetrics and Gynecology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
Tamura
Hiroshi
H
Takasaki
Akihisa
A
Yamagata
Yoshiaki
Y
Shimamura
Katsunori
K
Sugino
Norihiro
N
D000328:Adult; D001808:Blood Vessels / Q000473:pathology; D002452:Cell Count; D004717:Endometrium / Q000098:blood supply / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D004958:Estradiol / Q000097:blood; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000097:blood / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology*; D009929:Organ Size / Q000502:physiology; D011374:Progesterone / Q000097:blood; D011446:Prospective Studies; D012039:Regional Blood Flow; D017154:Stromal Cells / Q000378:metabolism / Q000473:pathology; D014463:Ultrasonography; D014599:Uterus / Q000098:blood supply / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D055815:Young Adult
C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D011374:Progesterone; D004958:Estradiol