Concerning twin-to-twin transfusion syndrome (TTTS), the following statements are correct:

• A. True
• B. False: TTTS occurs in monochorionic (shared placenta) pregnancies, not dichorionic diamniotic.
• C. True
• D. False: Severe TTTS has a poor prognosis (perinatal death >80%) without treatment, not an excellent one.
• E. True

TTTS facts

• Caused by placental vascular anastomoses in monochorionic (not dichorionic) twins.
• Donor: hypovolaemia, anaemia, oligohydramnios, stuck twin, IUGR. Recipient: hypervolaemia, polyhydramnios, cardiac failure, hydrops.
• Severe TTTS (stage 2 or above) has a perinatal death rate >80% without treatment.
• Treatment: fetoscopic laser ablation of anastomoses (or amnioreduction; selective fetocide).

Why A is true

TTTS is due to anastomoses in monochorionic twins.

Why B is false

TTTS occurs in monochorionic, not dichorionic diamniotic, pregnancies.

Why C is true

Donor oligohydramnios, recipient polyhydramnios.

Why D is false

Severe TTTS has a poor prognosis (perinatal death >80%) without treatment.

Why E is true

Fetoscopic laser ablation is a treatment.