Estrogen-progestin Contraceptive Use During Adolescence Prevents Bone Mass Acquisition: a 4-year Follow-up Study

Background: Estrogen-progestin contraception may affect estrogen production and alter the development of peak bone mass.

Study Design: A 4-year follow-up with 122 adolescent women aged 12-19 years. The data were divided into three groups based on estrogen-progestin contraceptive (EPC) use: (i) nonusers (n=52), (ii) 1-2 years of use (n=24) and (iii) use for more than 2 years (n=46). The estrogen dose of the preparations was < or =35 mcg. Height, weight, and the amount of exercise (ratio of work metabolic rate, h/week) as well as bone mineral content (BMC) of lumbar spine and femoral neck were measured repeatedly.

Results: There was a significant trend showing less of an increase in the mean adjusted BMC of lumbar spine in the group of adolescent women who had used EPC for more than 2 years compared with the two other groups. In the mean adjusted BMC of the femoral neck, there was a significant trend of a smaller increase in EPC users for more than 2 years compared with 1-2 years of use.

Conclusions: Long-term EPC with low-dose estrogen preparations seems to suppress normal bone mineral accrual in adolescent women.