Imperforate hymen presenting as vaginal cyst in a 16-month-old child - considerations for an early diagnosis.

Imperforate hymen is a congenital anomaly of female external genitalia, which is mostly diagnosed in puberty, at the age of 9-13 years, or very rarely at a younger age. Clinical picture varies from abdominal pain and low back pain to acute urinary retention. We describe a case of a 16-month-old female infant where the imperforate hymen presented as a vaginal cyst. The cyst was first observed by the patient's mother, although the child had been examined by a paediatrician on several occasions after birth. Complete workup performed for differential diagnosis, mostly to exclude other reproductive system anomalies, led to the final diagnosis of imperforate hymen. The aim of this report is to emphasise the necessity of thorough examination of genitalia in female newborns in order to avoid possible complications associated with this diagnosis later in life, as well as other, more severe differential diagnostic anomalies.