Bone mineral density in users of two kinds of once-a-month combined injectable contraceptives

Abstract

Objective The objective of this descriptive study was to compare bone mineral density (BMD) between users of two kinds of once-a-month combined injectable contraceptives (CICs) and control subjects. Subjects and Methods This cross-sectional descriptive study included 97 women aged between 20 and 45 years using CICs containing either 25 mg of medroxyprogesterone acetate and 5 mg of estradiol cypionate for 12–82 months or 50 mg of norethindrone enanthate and 5 mg of estradiol valerate for 12–60 months, matched by age (±1 year) and body mass index (BMI; kg/m 2) (±1) with users of the TCu 380A intrauterine device as control subjects. BMD was evaluated at the midshaft of the ulna and at the distal section of the radius of the nondominant forearm using double X-ray absorptiometry. Results There was no difference in BMD between users of either CIC and nonusers at either section of the forearm studied. There was also no difference in BMD between users of the two CICs at either section of the forearm. Conclusions Women aged between 20 and 45 years, currently using one of these two kinds of CICs, presented BMDs similar to those of control subjects paired by age and BMI.