Hello. It would be helpful to have a little more information here. If you're sexually active, one possible cause of your symptoms is
genital herpes, which is caused by one of two herpes viruses (
HSV-1 or
HSV-2). Genital herpes is acquired through sexual contact -- either oral or genital -- and, once you're infected, the virus persists in your body for the remainder of your life. Some people with genital herpes have frequent outbreaks, while others have rare recurrences, and still others remain symptom-free after their initial infection.
Another possibility here -- whether you're sexually active or not -- is
folliculitis, which occurs when bacteria enter a hair follicle and begin multiplying. Folliculitis is more common in people who shave their genitals, as shaving breaks down your skin's immune barriers and irritates your hair follicles. Folliculitis can often be addressed by stopping shaving for a few days and/or applying warm packs, but sometimes antibiotics are required. As folliculitis heals it may leave darkened areas of skin that can persist for several weeks or even months. This condition, called post-inflammatory
hyperpigmentation, is not dangerous.
Since it isn't possible to diagnose your condition without an examination, if you have ongoing concerns about these spots you should see your physician.
I hope that all helps!