Sep 05, · Some of the most common causes of genital rashes are infections: Jock itch, a fungal infection, or ringworm of the groin area. The rash is red, itchy, and scaly, and it may blister. Diaper rash, a Author: Mary Ellen Ellis. Itchy rashes near the groin often appear due to a yeast infection as well. The skin in the groin area is extremely sensitive and may show allergic reactions when exposed to certain chemicals present in detergents, soaps, deodorants, and latex used in condoms.