Serum procollagen I carboxyterminal propeptide (PICP) levels through puberty: relation to height velocity and serum hormone levels. 
The synthesis of type I collagen, the major component of the organic bone matrix, is reflected by procollagen I carboxyterminal propeptide (PICP) levels.  Conflicting reports have been made about the relationship between PICP levels and puberty.  We have studied PICP levels in serum in relation to pubertal stage, height velocity, oestradiol, testosterone, androstenedione, dehydroepiandrosterone sulphate, insulin-like growth factor I and growth hormone levels in 32 healthy boys aged 7.2-15.8 years and 32 healthy girls aged 7.2-14.8 years.  The PICP levels in girls tended to be higher during midpuberty: in boys the levels were higher at the end of puberty.  The PICP levels correlated strongly with height velocity in boys and girls.  In conclusion, PICP correlates especially with height velocity.  The variation of PICP between subjects during puberty is considerable.  The PICP levels may predict growth at a certain moment, especially in cases where only one height measurement is available.