Abstract
Twin girls born at term were noted to have hypertrophic and erythematous mucosal sulci extending from the posterior vaginal fourchette to the anterior ridge of the anus on their newborn exams. Pregnancy was complicated by gestational hypertension and dichorionic diamniotic twin pregnancy. No known traumas were sustained during delivery to either twin. Dermatology and obstetrics/gynecology were consulted who confirmed the diagnosis of perineal groove. Primary care follow-up was recommended, with referral to pediatric gynecology if the lesions did not epithelize by 2 years of age. Our case of perineal grooves is unique in that, to our knowledge, it is the first reported case of perineal grooves identified in both twins. Clinicians in the newborn nursery and primary care settings should perform routine genitourinary and anal examinations on all newborns to identify this benign lesion, which may limit misdiagnosis, inappropriate treatments, and invasive workups in the future.