Endometrial breakdown in women using Norplant is associated with migratory cells expressing matrix metalloproteinase-9 (gelatinase B)

Abstract

Norplant, subdermally implanted slow-release levonorgestrel, is an effective and widely used contraceptive agent but has a high rate of discontinuation due to unacceptable abnormal uterine bleeding. Matrix metalloproteinases (MMPs) are expressed in normal cycling endometrium and are postulated to be responsible for the tissue breakdown at menstruation. We have compared the immunolocalization of MMP-9 and migratory cells in endometrium from Indonesian women using Norplant with normal controls. Positive MMP-9 immunostaining was observed intracellularly within stromal and intravascular leukocytes and extracellularly in areas of tissue lysis adjacent to these migratory cells. The MMP-9 positive ..