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Professional Technical IVT

monoamniotic twins

Identical twins sharing both placenta and amniotic sac, representing the highest-risk twin pregnancy.

Full Definition

A rare form of monozygotic twinning where both twins develop within a single amniotic sac and share one placenta, occurring in approximately 1% of monozygotic twin pregnancies. This represents the highest-risk category of twin pregnancy due to the potential for cord entanglement, which can lead to fetal demise. Other complications include twin-twin transfusion syndrome and selective growth restriction. Management typically involves intensive monitoring from diagnosis and planned delivery between 32-34 weeks gestation to minimize the risk of sudden fetal death from cord accidents.

Usage

Usage note: Use 'MoMo' as informal shorthand only in internal communications; spell out fully in formal reports.

In Context

  • "Monoamniotic twins were diagnosed with evidence of cord entanglement at 18 weeks." — Ultrasound report
  • "MoMo twins require delivery planning by 34 weeks due to cord accident risks." — Management protocol

Also known as

monoamniotic monochorionic twins MoMo twins

Contrasted with

diamniotic twins

Don't confuse with

monochorionic diamniotic twins conjoined twins

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