Integrins as markers of uterine receptivity in women with primary unexplained infertility.
OBJECTIVE
To assess uterine receptivity in women with unexplained infertility using integrin cell adhesion molecules as markers.


METHODS
Prospective, controlled study design.


METHODS
Eighty-seven nulliparous women with unexplained infertility and 32 fertile and infertile parous controls.


METHODS
Immunohistochemical staining for alpha 1, alpha 4, and beta 3 integrin subunits in endometrial biopsies obtained during the window of implantation (days 20 to 24), using the semiquantitative HSCORE by two observers in a blinded fashion.


RESULTS
All endometrial biopsies from parous controls contained positive immunostaining for the alpha 1, and beta 3 integrin subunits in glandular epithelium. Some samples from parous controls were missing the alpha 4 subunit. In contrast, compared with parous controls, biopsies from women with unexplained infertility had reduced significantly beta 3 expression, with similar expression of alpha 1 and alpha 4. Two distinct defects in integrin expression were identified: "out-of-phase" samples that lacked beta 3 because of histologic lag (type I defects) and "in-phase" endometrium that still failed to express this integrin (type II defects). These subclassifications accounted for 26% and 39% of the total unexplained infertility group, respectively.


CONCLUSIONS
Abnormal endometrial integrin expression was a frequent finding in women with unexplained infertility. These data suggest that defective uterine receptivity may be an unrecognized cause of infertility in this population of women.
Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill 27599-7570.
B A
BA
Lessey
A J
AJ
Castelbaum
S W
SW
Sawin
J
J
Sun
D000328:Adult; D015415:Biomarkers / Q000032:analysis; D001706:Biopsy; D004717:Endometrium / Q000166:cytology / Q000473:pathology*; D005260:Female; D005298:Fertility; D006801:Humans; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D007247:Infertility, Female / Q000473:pathology*; D039423:Integrin alpha1; D039441:Integrin alpha4; D039661:Integrin beta3; D016023:Integrins / Q000032:analysis*; D015588:Observer Variation; D011446:Prospective Studies; D012016:Reference Values; D016037:Single-Blind Method; D014599:Uterus / Q000502:physiology* / Q000503:physiopathology
D015415:Biomarkers; D039423:Integrin alpha1; D039661:Integrin beta3; D016023:Integrins; D039441:Integrin alpha4