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What is Twin-Peak sign in First-trimester sonography signifies and explain in detail?
Two separate placentas suggest dizygosity. Identification of a thick dividing membrane generally 2 mm or greater suppos a presumed diagnosis of dichorionicity. The twin peak sign or Lamda sign is seen by examining the point of origin of the dividing membrane on the placental surface. The peak appears as a triangular projection of placental tissue extending a sho distance between the layers of the dividing membrane. Reference: William&;s Obstetrics; 24th edition; Chapter 45; Multifetal Pregnancy