Genital Herpes: This is a common STI that can cause atrophy in the genital area, especially if left untreated or if outbreaks are frequent. Symptoms can include painful blisters, itching, and burning sensations during urination.

Syphilis: In its later stages, syphilis can cause atrophy of the genital area, among other symptoms. Early stages may present with a painless sore, followed by a rash, and eventually, if untreated, can lead to more severe health issues.
Human Papillomavirus (HPV): Certain strains of HPV can lead to genital warts, which might cause discomfort or changes in the genital area that could be perceived as atrophy. Symptoms can include itching, bleeding, and visible warts.
Chlamydia: While primarily known for causing discharge and pain, untreated chlamydia can lead to complications like pelvic inflammatory disease (PID) in women, which might result in scarring and atrophy of reproductive organs.

Lymphogranuloma Venereum (LGV): A less common STI that can cause significant complications, including atrophy and scarring of the genital and anal areas if not treated promptly. Symptoms can be mild at first but can progress to severe pain, swelling, and potentially life-threatening complications.
HIV: While not directly causing atrophy, HIV infection can lead to a weakened immune system, making an individual more susceptible to other infections that could result in atrophy. Early stages might be asymptomatic, but it's crucial to diagnose and treat to prevent progression to AIDS.

Granuloma Inguinale: A rare STI that can cause ulcerative lesions in the genital area, potentially leading to scarring and atrophy if not treated. Symptoms include painless, beefy-red ulcers without regional lymphadenopathy.
Molluscum Contagiosum: Although more commonly associated with skin lesions, in rare cases, molluscum contagiosum can affect the genital area and potentially cause atrophy if the lesions become extensive and lead to scarring. It's characterized by small, pearly, or flesh-colored bumps.