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.
Subject(s)
Bone Density , Contraceptive Agents, Female/administration & dosage , Absorptiometry, Photon , Adult , Body Mass Index , Cross-Sectional Studies , Estradiol/administration & dosage , Estradiol/analogs & derivatives , Female , Humans , Injections , Medroxyprogesterone Acetate/administration & dosage , Norethindrone/administration & dosage , Norethindrone/analogs & derivatives , Radius , UlnaABSTRACT
BACKGROUND: The aim of the study was to compare bone mineral density (BMD) before insertion and at 18 months of use of etonorgestrel- and levonorgestrel-releasing contraceptive implants. METHODS: One hundred and eleven women, 19-43 years of age, were randomly allocated to two groups: 56 to etonorgestrel and 55 to levonorgestrel. BMD was evaluated at the midshaft of the ulna and at the distal radius of the non-dominant forearm using dual-energy X-ray absorptiometry before insertion and at 18 months of use. RESULTS: There was no difference in baseline demographic or anthropometric characteristics, or in BMD of users of either model of implant. BMD was significantly lower at 18 months of use at the midshaft of the ulna in both groups of users. However, no difference was found at the distal radius. Multiple linear regression analysis showed that the variables associated with BMD at 18 months of use in both implant groups were baseline BMD, body mass index (BMI) and difference in BMI (0 versus 18 months of use). CONCLUSIONS: Women of 19-43 years of age using either one of the implants showed lower BMD at 18 months of use at the midshaft of the ulna, however, without a difference at the distal radius.
