Discordance in nuchal translucency measurements in monochorionic diamniotic twins as predictor of twin-to-twin transfusion syndrome.
OBJECTIVE
Discordance in nuchal translucency measurements in monochorionic diamniotic twin pregnancies was assessed as predictor of Twin-to-Twin Transfusion Syndrome.


METHODS
A total of 61 monochorionic diamniotic twins were enrolled. Nuchal translucency (NT) and crown-rump-length (CRL) discordance was calculated as the percentage of delta NT and CRL (absolute difference NT/CRL fetus 1 and fetus 2) of the largest measurement, and correlated with subsequent development of Twin-to-Twin Transfusion Syndrome.


RESULTS
Twin-to-Twin Transfusion Syndrome developed in 14/61 (23%) of cases. A NT discordance of 20% or more best predicted Twin-to-Twin Transfusion Syndrome development, with a sensitivity of 64% and a specificity of 78%. We found a positive predictive value of 50% and negative predicted value of 86% for Twin-to-Twin Transfusion Syndrome development if NT discordance was 20% or more.


CONCLUSIONS
NT discordance of more than 20% in monochorionic diamniotic twins is associated with an increased risk for subsequent development of Twin-to-Twin Transfusion Syndrome, and with earlier presentation of symptoms.
Linskens
Ingeborg H
IH
Department of Obstetrics and Gynaecology, VU University Medical Center, Amsterdam, The Netherlands. I.Linskens@vumc.nl
de Mooij
Yolanda M
YM
Twisk
Jos W
JW
Kist
Willem J
WJ
Oepkes
Dick
D
van Vugt
John M
JM
D000328:Adult; D005260:Female; D005330:Fetofetal Transfusion / Q000175:diagnosis / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D048208:Nuchal Translucency Measurement; D011237:Predictive Value of Tests; D011247:Pregnancy; D014427:Twins