The Significance of Yolk Sac Number in Monoamniotic Twins

Conclusions: Two yolk sacs are present in up to a third of all MCMA twin pregnancies, dispelling the original concept that a single yolk sac is diagnostic of MCMA pregnancies. Yolk sac number should not be used to determine amnionicity. The presence of two yolk sacs on first trimester ultrasound is associated with an increased rate of male fetuses. The number of yolk sacs has no other significant impact on perinatal outcomes.Fetal Diagn Ther
Source: Fetal Diagnosis and Therapy - Category: Perinatology & Neonatology Source Type: research