A 26-year-old mother delivered a baby with fusion of both lower limbs, absent genitalia, absent anal orifice and single umbilical artery (Fig. 1). The baby cried immediately after birth and required no resuscitation but died within 5 hours. The skeletogram revealed absences of pelvic bones, fusion of both femora resulting in single thighbone and rudimentary tibia & fibula (Fig. 2). Autopsy revealed that kidneys, ureter and urinary bladder were absent, undetermined genital structures and rectum ending into a blind pouch.

Fig 1. Sirenomelia baby	Fig 2. Infantogram of baby with Sirenomelia.

Sirenomelia (mermaid baby) sequence is a rare developmental defect of the posterior axis caudal blastima with reported incidence of 1:60000 live births. It is characterized by the fusion of both lower limbs, absent genitalia and anal orifice and renal agenesis. The inci-dence is increased in monozygotic twins. Etiology is unknown with a male prepordence.

The antenatal diagnosis of sirenomelia by X-ray and ultrasonography has been reported. Sometimes because of oligohydramnios the diagnosis of sirenomelia is missed out. As it is possible to demonstrate sirenomelia as early as 20 weeks of pregnancy and it being a lethal anomaly, an early diagnosis could be useful in terminating the pregnancy.