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[Osteoporosis and hormonal contraception].

OBJECTIVE
To analyse the influence of the contraceptive treatment on bone mass.


DESIGN
Literary review.


SETTING
Department of Gynaecology and Obstetrics, 1st Faculty of Medicine, Charles University, Prague, Czech Republic.


METHOD
Informations were collected from full-texts which were taken from database Medline.


RESULTS AND CONCLUSION
The lowering of bone turnover under combined oral contraception was shown in all studies. It is favourable for bone mineral density after 30 years when bone loss starts. The positive influence is significantly dependent on the length of treatment. Only gestagen drugs have no positive effect on bone mass. The influence of contraception on mineral density in term of physiological bone density increasing before 20-25 year is not clear. Some of studies informed us about adverse effects of extremely-low dose oral contraception on mineral density in this group.