Genetics and developmental pathology of twinning
Martin A Weber1, Neil J Sebire
1Department of Paediatric Pathology, Great Ormond Street Hospital for Children, London, UK.
Seminars in Fetal & Neonatal Medicine
|July 29, 2010
Summary
Twin pregnancies have a higher risk of congenital anomalies. This review examines risks related to zygosity, chorionicity, and genetics, including unique monochorionic complications and perinatal mortality factors.
Area of Science:
- Perinatology
- Reproductive Medicine
- Genetics
Background:
- Twin pregnancies carry an elevated risk of congenital malformations compared to singleton gestations.
- Understanding the factors influencing these risks is crucial for improving perinatal outcomes.
Purpose of the Study:
- To review the risks of congenital anomalies in dizygotic and monozygotic twin pregnancies.
- To explore associations between zygosity, chorionicity, and genetic factors in twin malformations.
- To detail specific malformations in monochorionic twins and address perinatal mortality.
Main Methods:
- Literature review of studies on twin pregnancy and congenital malformations.
- Analysis of associations between zygosity, chorionicity, and genetic factors.
- Discussion of pathological mechanisms for unique monochorionic complications.
Main Results:
- Twin pregnancies, particularly monozygotic, show increased congenital malformation rates.
- Zygosity and chorionicity are significant factors influencing anomaly risk.
- Monochorionic twinning is linked to specific conditions like conjoined twins and TRAP sequence.
Conclusions:
- Congenital malformations are a significant concern in twin pregnancies.
- Zygosity, chorionicity, and genetic factors play key roles in twin anomaly development.
- Addressing these factors is vital for reducing perinatal mortality in multiple births.
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