Since what is required for an erection is good blood flow and a healthy nerve pathway, it would seem that something is amiss in one or the other of those areas. How could that relate to HGH? I would probably start taking a look at the possible connections and just eliminate them one by one. Enlarged prostate? High Blood pressure? Enlarged heart? Swelling of tissues to the point of impeding blood flow or nerve pathways to your groin area? Maybe an old injury of the spine or peripheral area that is being pinched by the tissue swelling of a beginning HGH cycle? Radical change in mineral balance (potassium, magnesium, calcium, sodium, etc.)? Radical change in blood sugar levels (maybe undiscovered diabetes complicated by HGH use)? Or ????

I would start by investigating these and seeing if you can isolate something that would clue you in on which is the problem. If you had zero issues up to this point, and the ONLY variable is HGH, then I would think it would be something along the list above ... even though you must be one of the one-in-a-billion class of side effects. HGH is worlds more likely to offer an assist in the erection department that to interfere with one, and certainly the side effects listed above are REALLY out of the scope of the norm.

Best of luck on tracking down the source of your woes, and also in your anti-aging endeavors. I would be interested in hearing what you find out.