Body composition and resting metabolic rate of perimenopausal women using continuous progestogen contraception

Objective The effect on body composition and in particular on fat mass (FM) of 12 months' use of a desogestrel (DSG)-only contraceptive pill or the levonorgestrel-releasing intrauterine system (LNG-IUS) was evaluated in women in the perimenopause. Methods An observational study comprised 102 perimenopausal women: 42 received a 75 μg DSG pill, 34 received the 52 mg LNG-IUS, and 26 received no treatment. Body composition, body weight and resting metabolic rate (RMR) were evaluated at baseline and again after 12 months. Results FM did not change in the control group (- 0.5 ± 1.6%) but significantly increased in the LNG-IUS group (+ 1.1 ± 2.9%; p = 0.02 vs. controls) and in the DSG group (+ 2.8 ± 3.5%; p = 0.0001 vs. controls; p = 0.02 vs. LNG-IUS). Women treated with DSG or the LNG-IUS showed a non-significant increase in body weight, body mass index and waist circumference. RMR did not significantly vary in the control group (- 3.8 ± 292.9 kJ/ 24 h) and tended to decrease but not significantly in the LNG-IUS (115.5 ± 531.8 kJ/ 24 h) and DSG groups (305.9 ± 556.9 kJ/24 h). Conclusions The results of this preliminary study seem to indicate that in perimenopausal women continuous use of the DSG-only pill and to a lesser extent the LNG-IUS may favour FM accumulation.