Intrauterine administration of levonorgestrel 5 and 10 μg/24 hours in perimenopausal hormone replacement therapy. A randomized clinical study during one year

Abstract

Objective. To investigate the clinical effects especially with regard to histopathology and bleeding patterns by levonorgestrel (5- or 10 μg/24 h) released from an intrauterine system (IUS) in combination with estradiol valerate (2 mg) given daily or transdermal estradiol (50 μg/24 h) in perimenopausal women. Design. A prospective randomized single blind comparison during twelve months. Subjects. One hundred and twelve perimenopausal women with vase-motor symptoms. Outcome measures. Histopathological assessment of the endometrium, ultrasonographic measurement of endometrial thickness, bleeding patterns, and acceptability. Results. A total of 108 women started the study and 12 discontinued. The most common reason for discontinuation was frequent bleeding (six women). Thus, 96 (89%) women were followed for twelve months. In both the 5- and 10 μg levonorgestrel IUS groups the endometrium in all women but one was non-proliferative after twelve months and no case of hyperplasia was found. Irregular bleeding was reported during the first months of treatment but decreased after six months. At the end of the study 62% in the 5 μg- and 61% in the 10 μg group were amenorrhoic. The effects on bleeding patterns did not differ between the two levonorgestrel dosages. Conclusion. Continuous combined HRT was well accepted in perimenopausal women when the progestogen was given in an IUS. IUS's releasing 5- or 10 μg/24 h levonorgestrel seemed to minimize the progestogenic side effects and proved to be sufficient for effective prevention of endometrial stimulation by estrogen treatment in HRT in perimenopausal women.