Trisomy 18 and trisomy 13 are conditions often referred to as "incompatible with life" or "lethal anomalies." If there is long-term survival, the outlook is considered "grim." Developmental status is presumed to be minimal. Yet, Baty et al. [1994; 49:189-194] described a variety of developmental skills in their sample. An additional 22 children with trisomy 18 and eight with trisomy 13 are desc...
