The influence of levonorgestrel intrauterine system on endometrial VEGF/Ang-1/Ang-2 of women with adenomyosis

Objective To determine the alteration of endometrial VEGF/Ang-1/Ang-2 expression of women with adenomyosis after using levonogestrel intrauterine system,and elucidate the possible mechanism of breakthrough bleeding in the use of LNG-IUS on angiogenesis and vascular stability.Methods Endometrial biopsies was obtained from 41 women with adenomyosis undergoing treatment with LNG-IUS by using Pipelle suction curette,determine the endometrial VEGF/Ang-1/Ang-2 expression through immunohistochemistry.We also took the endometrial tissue from patients diagnosed as adenomyosis without any treatment as control groups.Results The LNG-IUS group was divided into bleeding group (16 cases) and non-bleeding group (25 cases),according to the bleeding patterns in the last 3 months before biopsy.The staining for VEGF/Ang-2 in bleeding group was significantly higher than that in nonbleeding group (P0.05).The Ang-1 staining in glandular epithelium and stromal cells between two groups was not significant different (P0.05).Divided the LNG-IUS group into the less than 1-year group,1-2 year group and more than 2-year group,we had found that the 1-2 year group and the more than 1-year group exhibited significantly lower immunoreactivity for VEGF and Ang-2 in both glandular epithelium and stromal cells (P0.05),while there were no significant differences in immunoreactivity for the Ang-1 among different groups (P0.05).Conclusion VEGF and Ang1,Ang-2 may play a role in provoking breakthrough bleeding in the use of LNG-IUS by influencing angiogenesis and vascular stability.