title: Antenatal detection of grossly distended bladder owing to absence of the urethra in a fetus with trisomy 18.
abstract: An ultrasonic examination revealed a grossly distended fetal abdomen. Amniocentesis at 19 weeks' gestation showed raised amniotic fluid alphafetoprotein, a second band of specific acetylcholinesterase, and a fetal karyotype 47,XY,+18. The pregnancy was terminated and the necropsy examination showed absence of the urethra, grossly distended bladder, hydroureters, and congenital heart anomalies.
mesh_terms: D000328:Adult; D002869:Chromosome Aberrations / Q000175:diagnosis*; D025063:Chromosome Disorders; D002902:Chromosomes, Human, 16-18; D004108:Dilatation, Pathologic; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D011296:Prenatal Diagnosis; D014314:Trisomy; D014521:Urethra / Q000002:abnormalities*; D001745:Urinary Bladder Diseases / Q000196:embryology / Q000209:etiology