Comparison of anthropometric and densitometric variables and bone formation markers after 24 months between adolescents receiving low-dose oral contraceptives and the control group.
bone mass gain
Note: Controls: adolescents who did not use oral contraceptives.COC1: adolescents receiving an oral contraceptive containing 20 μg EE/150 μg desogestrel.COC2: adolescents receiving an oral contraceptive containing 30 μg EE/3 mg drospirenone.BMI: Body mass index; BMD: Bone mineral density; BMC: Bone mineral content; BAP: Bone alkaline phosphataseANOVA for comparison of means between the three groups. Different lowercase letters indicate significant differences between the three groups (p<0.05). Bonferroni test for multiple comparisons between the three groups.An average bone mass gain in all segments was observed in the control group, with a gain of 4.85 g in lumbar BMC and of 0.051 g/cm2 in lumbar BMD. Different results were obtained for the COC2 group, with a reduction of 0.012 g/cm2 in lumbar BMD and of 0.43 g in lumbar BMC (p = 0.001). An increase in the lumbar spine densitometric parameters was observed among users of EE/Desogestrel (COC1) but this increase was lower than that detected in adolescents of the control group (2.15 g in lumbar BMC and 0.019 g/cm2 in lumbar BMD; p = 0.258 and p = 0.342, respectively). Analysis of total body BMD and BMC after 24 months showed an increase in the control group but not in the groups of COC users (p<0.05). Subtotal BMC decreased in the COC2 group after 24 months (reduction of 1.47 g), while the control group exhibited an increase of 100.83 g and the COC1 group of 21.56 g over the same follow-up period (p = 0.005) (