A larger study with longer follow-up concluded that "use of DMPA during pregnancy or breastfeeding does not adversely affect the long-term growth and development of children". This study also noted that "children with DMPA exposure during pregnancy and lactation had an increased risk of suboptimal growth in height," but that "after adjustment for socioeconomic factors by multiple logistic regression, there was no increased risk of impaired growth among the DMPA-exposed children." The study also noted that effects of DMPA exposure on puberty require further study, as so few children over the age of 10 were observed. 
Earlier age hair loss and hair graying are a sign of overall rapid body ageing in some (but definitely far from all) people. In the latest BBC article that I linked to above, one of the scientists quoted suggests that DNA damage from ageing was a potential reason for early onset hair loss, early onset hair graying and early onset heart disease. Of course there are many people who go bald or grey very early and live to be over a 100 with no signs of heart disease…probably because they have certain genetic protections (., high HDL “good” cholesterol levels ) towards heart disease.
DHT is a potent agonist of the AR, and is in fact the most potent known endogenous ligand of the receptor. It has an affinity (K d ) of to nM for the human AR, which is about 2- to 3-fold higher than that of testosterone (K d = to nM)  and 15–30 times higher than that of adrenal androgens .  In addition, the dissociation rate of DHT from the AR is 5-fold slower than that of testosterone.  The EC 50 of DHT for activation of the AR is nM, which is about 5-fold stronger than that of testosterone (EC 50 = nM).  In bioassays , DHT has been found to be - to 10-fold more potent than testosterone.