Ouch, there's a page I'd rather not see again, lol.
But in all seriousness and lack of unnecessary sarcasm, isolated growth hormone deficiency (IGHD) typically (more like almost always) results in a penile size deficit. In clinical studies, HGH treatment improved the growth of the genitalia and gonads in prepubertal boys at a very successful rate (18/20). These boys also grew up to have normal genitalia and gonads.
I don't think you're going to have any luck finding studies where hGH was administered to boys with normal penile size, Times, but in the studies that have been done on boys with a IGHD, it is very obvious that hGH affects penis size in prepubescence. Adults that suffered from IGHD grew up to have subnormal sized genitalia and gonads. Had they been administered with hGH before puberty,
they wouldn't have grown up to be steroid.com moderators. Just joking
PMID: 6406387 [PubMed - indexed for MEDLINE]