Cite

Figure S1

Ultrasound images of umbilical flow according to the classification of FGR in MC twins by Gratacós et al.20 FGR, foetal growth restriction; MC, monochorionic.
Ultrasound images of umbilical flow according to the classification of FGR in MC twins by Gratacós et al.20 FGR, foetal growth restriction; MC, monochorionic.

sFGR definition by expert consensus: A Delphi procedure.

Definition establish in Delphi procedure
DC twins MC twins
EFW <3rd centile or
EFW of one foetus <10th centile EFW of one foetus <10th centile
AC is not taken into account AC of one foetus <10th centile
The disproportion between foetal weight ≥25% The disproportion between foetal weight ≥25%
UAPI of smaller foetus >95th centile UAPI of smaller foetus >95th centile
2/3 have to be present to recognise sFGR 2/4 have to be present to recognise sFGR

Assessment of hypertrophic twin pregnancies depending on chorionicity.

sFGR twins Color Doppler Foetal growth assessment
DC Biweekly or more frequent Biweekly
MC Once a week or more frequent

sFGR definition in twins among societies.

Society Date of publication Definition of sFGR Growth charts Other twins recommendation
NICE 2019 ≥25% EFW discordance and EFW of one foetus <10th centile for GA Undefined
ACOG 2019 One foetus has EFW <10th centile and disproportion between EFW >20% Undefined
ISOUG 2016 One foetus has EFW <10th centile and the intertwin weight discordance >25% Singleton
RAN-ZOG 2017 Undefined Undefined Recommendation about MC twins but without definitions of FGR
SOGC 2017 AC and/or EFW of one or both twins are <10th centile or when growth discordance is identified Singleton
ACR 2017 One foetus EFW <10th centile and the intertwin EFW discordance >25% Singleton
FIGO 2019 One foetus EFW <10th centile and the intertwin EFW discordance >25% Twin
Delphi consensus 2019 Separates MC and DC twins, EFW <3rd centile or contributory factors Singleton

Recommended GA at delivery in stable twins pregnancies complicated by sFGR according to Doppler assessment compared with FGR singleton pregnancies.

sFGR Type
Chorionicity I II III IV
DC UAPI >95th centile CPR <5th centile AEDF REDF, DV PI >95th centile DV a wave reversed
MC I II III
UAPI >95th AREDF iAREDF DV a wave reversed (it is not stage IV in MC)
Recommended GA at delivery (weeks)
DC 34–36 30–32 30–32 >26 <26 expectant management or selective termination

This is the UK-recommended treatment. In Poland, it is not legally possible to terminate a pregnancy or perform selective termination after the end of 22 weeks.

MC 34–36 30–32 30–32 >26 <26 SLPCV, selective termination (RFA, cord occlusion)
Singletons 37 34 30 26 <26 expectant management

The perinatal outcome of the second twin in the case of IUD of sFGR foetus depends on chorionicity.

Perinatal outcome DC MC
Second twin IUD 3% 15%
Preterm labour before 32 weeks 54% 68%
Abnormalities in CNS imaging of survivor 16% 34%
Neurodevelopment retardation of survivor 2% 26%
eISSN:
2719-535X
Language:
English