Journal of Ultrasound in Medicine, Vol 8, Issue 2 83-88, Copyright © 1989 by American Institute of Ultrasound in Medicine
Prenatal diagnosis of sirenomelia
M. Sirtori, A. Ghidini, R. Romero and J. C. Hobbins
Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Connecticut 06510.
Prenatal sonographic findings of sirenomelia (or mermaid fetus) were
retrospectively reviewed in eleven proven cases. Sonography showed
oligohydramnios in all the cases, five (45%) of which had severe
oligohydramnios that limited prenatal diagnosis by poor visibility. In five
cases (45%), sirenomelia was correctly diagnosed by ultrasound; in the
remainder, only bilateral renal agenesis was identified. All eleven fetuses
had other associated malformations: congenital heart defects (4), skeletal
deformities (10), and abdominal wall defects (4). Death resulted from
termination of pregnancy in six cases and stillbirth in three cases. Two
newborns died at 24 and 36 hours of neonatal life, respectively. We
concluded that some cases of sirenomelia can be detected on prenatal
sonograms by demonstration of a single lower extremity, oligohydramnios,
and bilateral renal agenesis. Sirenomelia is a lethal condition and can be
detectable in the second trimester of pregnancy, allowing for termination
of pregnancy.
