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Blood flow changes in dichorionic twins with growth discordance
Mariola Ropacka-Lesiak1, Grzegorz Bręborowicz, Anna Dera
1Department of Perinatology and Gynecology, Poznan University of Medical Sciences, Poznan, Poland.
Summary
Doppler ultrasonography effectively predicts adverse outcomes in dichorionic twins with growth discordance. Umbilical artery pulsatility index (PI) differences are key indicators for fetal well-being and small for gestational age (SGA) risk.
Area of Science:
- Maternal-fetal medicine
- Diagnostic imaging
- Perinatology
Background:
- Dichorionic pregnancies with fetal growth discordance face increased risks.
- Accurate prediction of pregnancy course and neonatal outcome is crucial.
Purpose of the Study:
- To assess Doppler ultrasonography's role in predicting pregnancy outcomes in dichorionic twins with growth discordance.
- To evaluate umbilical artery (UA) and middle cerebral artery (MCA) pulsatility index (PI) for predictive value.
Main Methods:
- Doppler examination of UA and MCA in 106 dichorionic twins.
- Defined abnormal UA PI (>95th percentile) and MCA PI (<5th percentile).
- Assessed UA PI difference of ~0.5 between twins as abnormal.
Main Results:
- Abnormal UA PI and PI difference correlated with earlier delivery, severe growth discordance, low birth weight, and adverse fetal outcomes.
- Cerebro-umbilical (C/U) ratio abnormalities linked to lower birth weight, adverse outcomes, and preterm delivery risk.
- MCA PI showed poor correlation with neonatal outcomes.
Conclusions:
- The UA PI difference of ~0.5 demonstrated the highest predictive value for adverse fetal outcomes and small for gestational age (SGA) risk.
- UA PI and C/U ratio showed limited sensitivity.
- MCA PI was less effective in predicting outcomes.
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