THE PROGNOSIS OF FETUSES WITH TRANSIENT NUCHAL TRANSLUCENCY IN THE FIRST AND EARLY 2ND-TRIMESTER

Objective. The purpose of this study was to evaluate the prognosis of fetuses with transient nuchal translucency before 15 weeks of gestatio n. Study design. A nuchal translucency's measurement of greater than o r equal to 5 mm was considered abnormal. In the period from 1994 to 19 95, twelve fetuses were diagnosed at our institution with nuchal trans lucency. The fetuses all underwent karyotyping and a complete ultrason ographic search for any associated anomalies and a resolution of nucha l translucency at 1-2 week gestational age intervals. Results. Five ca ses ('Transient NT') demonstrated transient nuchal translucency. Seven cases ('Persistent NT') demonstrated persistent nuchal translucency. The 984 cases with no or less than 5 mm of nuchal translucency (contro l group) gave birth at the same lime. The mean initial week of diagnos is was 12.0 +/- 1.6 weeks in 'Transient NT', and 13.6 +/- 1.8 weeks in 'Persistent NT:. The mean maternal age was 30.8 +/- 6.3 years old in 'Transient NT', 28.9 +/- 3.0 years old in 'Persistent NT', and 30.5 +/ - 43 years old in the control group. Abnormal karyotypes were detected in one case in 'Transient NT', and in four cases in 'Persistent NT'. Structural malformations were detected in two cases (40%) in 'Transien t NT', seven cases (100%) in 'Persistent NT', and 30 cases (3.0%) in t he control group. Conclusions. Regardless of the spontaneous resolutio n of abnormal nuchal translucency, there was a high association with b oth karyotypical and structural abnormalities, and the prognosis of su ch cases was generally poor, especially persistent NT's prognosis.