CHAPTER 114 Hydrometrocolpos

Introduction Hydrocolpos is an uncommon congenital disorder consisting of cystic dilatation of the vagina caused by obstruction of the distal genital tract, resulting in retained fluid. If there is also associated uterine enlargement, the term hydrometrocolpos is applied. Vaginal obstruction may result from a high vaginal septum, varying degrees of vaginal atresia, cloacal malformations, or an imperforate hymen. Hydrocolpos may manifest at birth as a palpable mass or it may present at puberty as progressive accumulation of menstrual blood, causing haematometrocolpos. Hydrocolpos and hydrometrocolpos are the third most common causes of all abdominal masses in the newborn, accounting for 15% of all abdominal masses in female newborns, with an estimated occurrence rate of 1 in 16,000 female deliveries. The clinical features of hydrometrocolpos in the newborn are dominated by the abdominal mass with regional compression (Figure 114.1). An overly distended vagina can compress the adjacent organs and cause abdominal pain, intestinal obstruction, ureteral obstruction, hydronephrosis, bladder perforation, respiratory distress, and lower extremity venous stasis. Accordingly, presentation of hydrometrocolpos depends on the degree of compression of the surrounding structures by the uterovaginal swelling. Although the rarity and variable presentation of hydrometrocolpos can lead to delayed diagnosis and erroneous management, it should be considered in the differential diagnosis if a female neonate is found to have a large abdominal mass. Early diagnosis and treatment of hydrocolpos or hydrometrocolpos is important to minimise various complications of mechanical pressure exerted on surrounding structures. The most important step is a comprehensive perineal examination. Cross-sectional imaging and dye studies help in early diagnosis and demarcating the exact anatomy as well as revealing associated renal anomalies.1 Comprehensive management is necessary, usually involving surgical treatment, to provide normal phenotypic appearance and to preserve reproductive potential. Demographics Prevalence data for Africa were not available. In general, the prevalence of hydrocolpos is estimated to be approximately 1 in 16,000 births.2 Imperforate hymen is the most frequent congenital malformation of the female genital tract.3 The incidence is estimated to be 0.1%.4 However, manifestations of imperforate hymen presenting as an abdominal mass in the perinatal or neonatal age are extremely rare, with an estimated incidence of 0.006%.4 Vaginal atresia is estimated to occur in 1 in 5,000 to 1 in 10,000 live female births; approximately 1 in 70,000 to 1 in 80,000 females are born with a transverse vaginal septum, with septa more frequently occurring in the middle and upper third of the vagina.5 Persistent cloaca has an incidence of 1 in 250,000 live born infants. Twenty-five percent of patients with persistent cloaca present with associated hydrocolpos.6