Effects of the copper intrauterine device on the expression of cyclooxygenase-1 and-2 in the endometrium

Objective: To examine the expression levels of cyclooxygenase (COX)-1 and COX-2 in the endometrium before and after insertion of the copper intrauterine device (Cu-IUD). Methods: Ten patients were investigated. Two endometrial biopsies were taken from the uterus of each patient. The first biopsy was taken prior to insertion of the Cu-IUD, and the second was taken I month after insertion on the same day of the menstrual cycle and from the same location. The levels of COX-1 and COX-2 mRNA and protein in the endometrium were determined using reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting. Results: Before insertion, expression of COX-2 mRNA and proteins was 0.399 +/- 0.014 and 14.75 +/- 1.31, respectively. Post insertion, expression of COX-2 mRNA and proteins was 0.563 +/- 0.041 and 18.61 +/- 1.93, respectively. A significant increase (P<0.05) of COX between pre and post insertion of the Cu-IUD was only seen with COX-2. There was no significant change in the level of COX-1 mRNA or proteins before and after insertion of the Cu-IUD. Conclusion: COX-2 is the primary isoenzyme stimulating overproduction of prostaglandins in the endometrium after the insertion of Cu-IUDs. (C) 2009 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.