Increased type III and V collagen expression in human corpora lutea in early pregnancy

Objective: To investigate the possible involvement of collagen in the characteristic structure and function of human corpora lutea (CL), type V collagen expression was determined,in the-CL-tissues during the menstrual cycle and early pregnancy. Design: In vitro experiment. Setting: Department of Obstetrics and Gynecology, Wakayama Medical University, Wakayama, Japan. Patient(s): Regulatory cycling women and pregnant women with ovarian tumor and ectopic pregnancy, who underwent adnexectomy. Intervention(s): Composition of the various types of collagen in human CL was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Main Outcome Measure(s): Expression of type V collagen. Result(s): The ratios of type III to type I collagen and the ratios of type V to type I collagen in the CL tissues were significantly increased in early pregnancy compared with those in the menstrual cycle. Conclusion(s): These results suggest that alterations in composition of collagen might play an important role in determining the physiology and structure of the CL during the menstrual cycle and early-pregnancy.