Sirenomelia is extremely rare congenital malformation that characterized by the complete or incomplete fusion of the low extremities and associated by the various organs’ disorders, such as urinary system, which determined the poor outcome in these infants that died during antenatal or early neonatal period. Prenatal ultrasonography, especially during first-second trimester, permits to establish the presence of sirenomelia. Due to the rarity of this malformation, the own observation of first case of sirenomelia in one infant from twins is presented, which borne in Ukraine. Diagnosis of sirenomelia was established at the planned ultrasonographic screening of multigravida mother. After the birth, neonate with sirenomelia was transferred at the intensive care unit of Lviv regional children’s clinical hospital «OXMATDYT». At the first examination, the throughout fusion of lower extremities, the absent of one kidney, bladder, and external genitalia was revealed. With increasing signs of renal and respiratory failure baby died at 9 days after birth. Conclusions. Sirenomelia is extremely rare congenital malformation that associated with the high mortality during early neonatal period due to the presence of underlying congenital malformations, such as urinary system. Ultrasonography during the prenatal period is the screening methods for the diagnosis of this malformation. No conflict of interest was declared by the authors. Key words: sirenomelia, diagnostic, twins.

Purpose – to analyze own results of surgical treatment of serious forms of disorders of sexual development (DSD) in children after feminizing surgeries. To define practical protocol guides on the choice of the type of surgical correction. Materials and methods. Over the past 5 years surgeons of Lviv regional paediatric clinical hospital «OHMATDYT» have examined 12 children with DSD, signs of hermaphroditism (intersex). After complex examination the following states were diagnosed: androgenital syndrome in 5 girls (referred for further treatment to Kyiv paediatric medical centres); true hermaphroditism – 1 child; mixed gonadal dysgenesis (MCG) – 3 children; female pseudohermaphroditism (without determining genesis) – 1 child; partial testicular feminization syndrome, Morris syndrome (male pseudohermaphroditism) – 2 children. In connection with marked masculinization of external genitalia two children with MCG and the girl with pseudohermaphroditism underwent feminizing surgery, namely genital zone reconstruction, mobilization and excision of urogenital sinus walls, excision of genital cavernous bodies (in children with MCG) with clitoroplasty, vulvoplasty with labioplasty and vaginoplasty. Children with Morris syndrome are being prepared to feminizing surgery. Results. Each child had a personal examination plan. Verification of a child’s state lasted from several weeks to 2–3 months. Children who underwent feminizing surgery did not have male structures and had relatively well-developed female structures. More «natural», less traumatizing correction was preformed for each specific case. In all children who underwent surgery vagina opened into urogenital sinus lower than external urethral sphincter, so there was no need to form front vagina wall (back and side walls were formed). Out of all children treated in our hospital gender was legally changed to the opposite. Conclusions. The birth of a child with DSD is a most challenging problem for parents, doctors, psychologists and social workers. Such states require complex examination. Children with severe hypospadias must undergo genetic examination. Statistic data and our own experience show higher frequency of feminizing surgeries in such cases. The most difficult part of such surgeries proves to be the excision of genital cavernous bodies with clitoroplasty and clitoris translocation; the most responsible part in functional sense is vaginoplasty. Surgical treatment is not the final stage of treatment for such patients. Children with DSD require constant further dynamic checkups by gynaecologists, urologists, oncologists, endocrinologists, psychologists with relevant therapy correction. The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local ethics committee of all participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Key words: disorders of sexual development (DSD), hermaphroditism, feminizing correction.