Raised alpha-fetoprotein levels in amniotic fluid and maternal serum associated with distension of the fetal bladder caused by absence of urethra.

Prune belly in trisomy 13

“…Prognosis in those babies born alive is determined by the amount of functional renal tissue remaining and the degree of pulmonary hypoplasia (Woodhouse et al, 1982). As well as being found as an isolated abnormality, on occasion with raised serum and amniotic AFP (Nevin et al, 1978), prune belly has been reported in association with trisomy 18 (Nevin et al, 1983). To assess fully a fetus in whom prune belly is diagnosed prenatally by USS, amniocentesis and fetal karyotype analysis should be performed.…”

Antenatal Ultrasonic Diagnosis of Complete Urethral Obstruction in the Fetus

“…The infant died at the age of two months. In Nevin's report ( 5 ) , an absence of the urethra was found, with an extremely distended bladder and other malformations in different organs. The infant died at birth.…”