Ok, I know steroids cause growth plate closure (GPC), in immature users (by immature I mean age wise, not in the sense of guys 35 year olds still watching "PowerPufF Girls:The Movie"), but I have always been under the impression that all gear does, not just gear that aromatizes into estrogen. Recently I have read posts saying that only the estrogen causes GPC, not the androgenic or anabolic hormones themselves. So in theory something like say Halo would not cause GPC. Is there scientific proof (in the form of therum), that any of you guys know about, and have a link to? This is a general question I'm an old man so I don't have to worry about it, my GP have been fused for years. Thanks and any info would be great.