Outcome prediction in monochorionic diamniotic twin pregnancies with moderately discordant amniotic fluid.
OBJECTIVE
The aim of this study was to identify predictors of twin-to-twin transfusion syndrome (TTTS) and selective intrauterine growth restriction (sIUGR) in monochorionic diamniotic (MCDA) twin pregnancies with moderate amniotic fluid discordance (mAFD).


METHODS
Monochorionic twins with mAFD (n = 45; gestational age, 15-29 weeks) were assessed for extent of fluid discordance, fetal growth discordance and fetal cardiac dysfunction, and were followed longitudinally. A prediction algorithm was constructed for TTTS and sIUGR and validated in an unrelated cohort (n = 52).


RESULTS
Cardiac dysfunction could not predict TTTS or sIUGR. Twins below 20 weeks of gestation with a fluid discordance of ≥ 3.1 cm had a risk of TTTS of 85.7%. Sensitivity for TTTS was nevertheless only 55%. An intertwin weight discordance of ≥ 25% had 63% sensitivity and 76% specificity for sIUGR without TTTS.


CONCLUSIONS
The outcome of MCDA twins with mAFD remains unpredictable, yet high-risk and low-risk subgroups for TTTS can be identified based on severity of fluid discordance and gestational age.
Van Mieghem
T
T
University Hospitals Leuven, Division of Woman and Child, Department of Obstetrics and Gynecology, Fetal Diagnosis and Therapy Unit, Leuven, Belgium.
Eixarch
E
E
Gucciardo
L
L
Done
E
E
Gonzales
I
I
Van Schoubroeck
D
D
Lewi
L
L
Gratacos
E
E
Deprest
J
J
D000653:Amniotic Fluid / Q000000981:diagnostic imaging*; D001530:Belgium / Q000453:epidemiology; D001699:Biometry; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging* / Q000453:epidemiology; D005330:Fetofetal Transfusion / Q000000981:diagnostic imaging / Q000453:epidemiology; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D011379:Prognosis; D013030:Spain / Q000453:epidemiology; D014430:Twins, Monozygotic; D016216:Ultrasonography, Prenatal