Kindly get your tri-pooled free testosterone level
at 9 AM. If it is normal, then your hormonal
profile is normal. Growth of hair on body is largely governed by Hormonal levels but this in turn is affected by genetic makeup. Some people have less growth of hair, despite normal hormonal profiles, running in families, while others have one or two members not having proper growth while others have good growth. This is explained by a newer explanation in Genetics and it is known by the name- EPIGENETICS. It means you have the genes meant to stimulate hair growth at adolescence but they are not turned on ie they remain non functional.
I am explaining this to you just to make sure that in case, your all reports are normal and Doctors ultimately conclude that their isn't going tobe a significant growth, you don't try silly things available in market