dichorionic diamniotic
Pronunciation: die-kor-ee-ON-ik die-am-nee-OT-ik
A type of twin pregnancy where each fetus has its own separate chorion and amnion, representing the lowest-risk twin configuration.
Full Definition
Dichorionic diamniotic (DCDA) twins represent the most common and lowest-risk type of twin pregnancy, where each fetus develops within its own separate chorion (outer membrane) and amnion (inner membrane). This configuration occurs in all dizygotic (fraternal) twins and approximately one-third of monozygotic (identical) twins, depending on when embryonic splitting occurs. DCDA twins have separate placental circulations, eliminating the risk of twin-to-twin transfusion syndrome and other complications associated with shared circulation. Chorionicity determination is best accomplished in the first trimester by identifying the lambda sign or twin peak sign at the membrane insertion site.
Usage
Usage note: Often abbreviated as DCDA. Chorionicity is more important than zygosity for pregnancy management.
In Context
- "Early ultrasound confirmed dichorionic diamniotic twinning with lambda sign present." — First trimester ultrasound report
- "The dichorionic diamniotic twins showed appropriate growth without signs of twin-to-twin transfusion syndrome." — Growth assessment report