The effect of etonogestrel on VEGF, oestrogen and progesterone receptor immunoreactivity and endothelial cell number in human endometrium

Contraceptive use often leads to disrupted endometrial bleeding patterns in women. In this study, two different contraceptive regimes (Mircette, a mon ophasic oral contraceptive and Implanon, a long-acting gestagen) were used and their effects on the immunoreactivity of vascular endothelial growth fa ctor (VEGF), oestrogen receptor (ER), progesterone receptor (PR) and endoth elial cell number were determined. During the untreated normal cycle, there was a significant increase (P = 0.005) in glandular VEGF immunoreactivity and a significant decrease (P < 0.05) in PR immunoreactivity in the mid- an d late secretory phases compared with the proliferative phase. There was a significant positive correlation (gamma = 0.38, P = 0.046) between stromal VEGF immunoreactivity and endothelial cell number. This correlation was als o apparent during treatment with Implanon, but not with Mircette, Disrupted bleeding patterns were associated with Implanon and, to a lesser extent, w ith Mircette, Both contraceptives significantly reduced glandular VEGF immu noreactivity, Implanon significantly increased (P = 0.016) glandular PR sta ining, but Mircette significantly reduced (P = 0.027) stromal PR staining w hen compared,vith secretory before-treatment biopsies. There were no change s in endothelial cell number or glandular or stromal ER during the normal c ycle, or with use of either contraceptive. There was no association between the parameters measured with bleeding patterns and histological category.