Clomiphene citrate does not affect the secretion of α3, αV and β1 integrin molecules during the implantation window in patients with unexplained infertility

BACKGROUND: The expression of integrin molecules on the endometrium suggests that certain integrins may participate in the cascade of molecular events leading to successful implantation. A prospective, controlled study was carried out to investigate the effect of clomiphene citrate (CC) on secretions of beta (1), alpha (3) and alpha (V) integrin molecules in the endometrium of patients with unexplained infertility during the implantation window. METHODS: A total of 40 endometrial samples was evaluated in both spontaneous (n = 13) and ensuing clomiphene-treated cycles (100 mg on days 5-9) and also from fertile women serving as controls (n = 14) during postovulatory 7th or 8th day of menstrual cycle. A semiquantitative grading system (H-score) was used to compare the inmumohistochemical staining intensities. Endometrial thickness and serum oestradiol and progesterone concentrations were also measured on the day of sampling. RESULTS: Staining of alpha (v) but not beta (1) and alpha (3) integrins was significantly less intense in infertile cases than fertile control cases (1.42 +/- 0.12 versus 2.21 +/- 0.13 respectively, P = 0.012) and this was not restored to normal concentrations with treatment. CONCLUSIONS: Our study indicated that cc treatment significantly decreased the endometrial thickness and increased oestradiol and progesterone concentrations. However, secretion of alpha (v,) beta (1) and alpha (3) integrin molecules, which might play a role in implantation, was not affected.