In 1994, we published a case with trisomy 13 who presented with ectrodactyly [Urioste et al., 1994: Am J Med Genet 53:390-392]. Recently, Kuschel and Gillessen-Kaesbach [2000: Am J Med Genet 90:87-88] presented an infant with trisomy 13 who also had oligodactyly, and they considered their case as the second published with oligodactyly. Here, we present three cases with any type of limb deficiencies who, together with the one that was published previously [Urioste et al., 1994], correspond to the total of 75 cases with trisomy 13 identified in the Spanish Collaborative Study of Congenital Malformations (ECEMC). This gives us a minimum frequency of 5.33% (CI:1.45-13.65) for trisomy 13 cases having limb deficiencies whereas these defects have a frequency of 5.51 per 10,000 births in our population. Consequently, we think that limb deficiencies could be considered as one of the defects that constitute the spectrum of anomalies observed in infants with trisomy 13.