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. 2025 Feb;65(2):253-276.
doi: 10.1002/uog.29166. Epub 2025 Jan 15.

ISUOG Practice Guidelines (updated): role of ultrasound in twin pregnancy

A Khalil  1 , A Sotiriadis  2 , A Baschat  3 , A Bhide  1 , E Gratacós  4 , K Hecher  5 , L Lewi  6 , L J Salomon  7 , B Thilaganathan  8 , Y Ville  9
Affiliations

ISUOG Practice Guidelines (updated): role of ultrasound in twin pregnancy

A Khalil et al. Ultrasound Obstet Gynecol. 2025 Feb.
No abstract available

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Figures

Figure 1
Figure 1
Ultrasound images in the first trimester of: (a) a dichorionic diamniotic twin pregnancy, in which the twins are separated by a thick layer of fused chorionic membranes; and (b) a monochorionic diamniotic twin pregnancy, in which the twins are separated by only two thin amniotic layers. In monochorionic twins, the base of the insertion may still be triangular (empty lambda/T sign (arrow)); however, it does not contain chorion and should not be confused with the full lambda/twin peak sign (arrow) of dichorionic twins.
Figure 2
Figure 2
Ultrasound monitoring pathway in uncomplicated dichorionic twin pregnancy.
Figure 3
Figure 3
Ultrasound monitoring pathway in uncomplicated monochorionic twin pregnancy. DVP, deepest vertical pocket; EFW, estimated fetal weight; MCA, middle cerebral artery; PI, pulsatility index; PSV, peak systolic velocity; UA, umbilical artery.
Figure 4
Figure 4
Classification of selective fetal growth restriction in monochorionic twin pregnancy. In Type I, the umbilical artery Doppler waveform has positive end‐diastolic flow, while in Type II there is absent or reversed end‐diastolic flow (AREDF). In Type III, there is a cyclical/intermittent pattern of AREDF.
Figure 5
Figure 5
(a) Midsagittal ultrasound image of pump twin in a pregnancy affected by twin reversed arterial perfusion (TRAP) sequence. (b,c) Sagittal views of TRAP mass. (d) Intrafetal laser treatment as a means to arrest the flow in the TRAP mass. The needle is positioned, under ultrasound guidance, in the TRAP mass in the fetal pelvis near the cord insertion.
See this image and copyright information in PMC

References

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