Imaging recommendation · Abdomen · Pelvis

Monochorionic-diamniotic twins with discrepant fluid / growth, suspected twin-twin transfusion syndrome

Q: What's the alternative imaging for monochorionic-diamniotic twins with discrepant fluid / growth, suspected twin-twin transfusion syndrome when severe (stage ii-iv) → fetal therapy candidate?

MRI — Fetal MRI + tertiary center referral for fetoscopic laser ablation (no contrast).

Recommended: Obstetric Ultrasound + serial AFI / fetal Doppler is the preferred imaging study for monochorionic-diamniotic twins with discrepant fluid / growth, suspected twin-twin transfusion syndrome. Mono-di twin pregnancy; one twin oligo (donor) + one polyhydramnios (recipient).

Recommended study

Obstetric Ultrasound + serial AFI / fetal Doppler

US No contrast Preferred Abdomen · Pelvis Outpatient Reviewed 2026-05

Mono-di twin pregnancy; one twin oligo (donor) + one polyhydramnios (recipient). Quintero stages I-V.

If the default doesn't apply

Severe (Stage II-IV) → fetal therapy candidate

MRI Fetal MRI + tertiary center referral for fetoscopic laser ablation No contrast

Watch-outs

Time-critical intervention

Stage III + (abnormal Doppler) — fetoscopic laser ablation between 16-26 weeks improves outcomes.

Co-twin demise

Risk of neuro injury / death in surviving twin from acute hemodynamic shift.

Pearls

Quintero stages: I (discordant fluid), II (no donor bladder), III (abnormal Doppler), IV (hydrops), V (demise).
Selective IUGR is a different mono-di complication — Type I/II/III based on Doppler patterns.
Laser photocoagulation of placental anastomoses is treatment of choice.