Prenatal Diagnosis of Trisomy 18

Abstract

Prenatal cytogenetic diagnosis of trisomy 18 was followed by induced termination of a 20-week pregnancy in a 40-year-old multipara; the fetus had recognizable phenotypic stigmata of trisomy 18. Among external

Three successive prenatal diagnoses of 47,XY,+21

“…Various chromosomal trisomies have been detected prenatally, such as trisomy 21 (Hsu et al 1973a, Milunsky 1973, trisomy 18 (Hsu et al 1973b), trisomy 13 (Butler et al 3973), trisomy 22 (Milunsky 1973), X X Y ), X Y Y (Hsu et al 1975), and X X X (our unpublished data). To our knowledge this is the first such occurrence of three successive pre-natal diagnoses of the same trisomy and the same sex.…”

The antenatal diagnosis of trisomy 18

“…The fetus had a crown-rump length which corresponded to only 20 weeks' gestation and the placenta was small. The finding of a small placenta in this syndrome has been recorded by Hecht (1963) and by Hsu et al (1973). The study of fetuses such as this may help to determine the time of onset of the retardation in growth and development usually associated with chromosome abnormality.…”

“…The pathological findings in the fetus are typical of those seen in neonates and older children with this syndrome (Taylor 1968). It is of interest that this fetus and the one described by Hsu et al (1973) both had a Meckel's diverticulum with a small nodule at its tip. In the present case this proved to be heterotopic pancreatic tissue.…”