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Updated: Jun 16, 2026
09:04
Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas
Published on: September 5, 2011
[Discordant anomaly in twin pregnancy]
1CMCO-SIHCUS, Service de gynécologie-obstétrique, 67300 Schiltigheim/Strasbourg, France. romain.favre3@orange.fr
Journal De Gynecologie, Obstetrique Et Biologie De La Reproduction
|February 10, 2010
Summary
Monochorionic pregnancies have a fourfold higher risk of fetal loss and increased malformations compared to dichorionic ones. Selective fetal reduction is complex, with specific interventions for conditions like twin-to-twin transfusion syndrome and selective IUGR.
Area of Science:
- Perinatology
- Maternal-Fetal Medicine
- Reproductive Genetics
Context:
- Monochorionic pregnancies carry a significantly elevated risk of fetal loss (4x) and malformations compared to dichorionic pregnancies.
- Selective intrauterine growth restriction (sIUGR) affects 12.5-25% of these pregnancies, with diagnostic challenges and low positive predictive value.
- Umbilical flow velocity waveforms (absent or intermittent diastolic flow) are critical indicators of mortality risk for the growth-restricted fetus and leucomalacia in the larger twin.
Purpose:
- To review the risks and management strategies for fetal complications in monochorionic and dichorionic pregnancies, including selective intrauterine growth restriction (sIUGR) and twin-to-twin transfusion syndrome (TTTS).
- To highlight the increased incidence and types of fetal malformations in twins, particularly monochorionic gestations, and discuss diagnostic and therapeutic approaches.
- To provide an expert viewpoint on interventions such as selective feticide and cord coagulation for complex twin pregnancy complications.
Summary:
- Monochorionic twins face higher risks of fetal loss and malformations, including central nervous system, urinary tract, and cardiovascular anomalies.
- Prenatal diagnosis of sIUGR is challenging, with specific umbilical flow patterns indicating poor prognosis and risks for both fetuses.
- Management strategies vary from intensive monitoring and genetic assessment to selective feticide or cord coagulation, depending on the specific condition and gestational age.
Impact:
- Improved understanding of risks associated with monochorionic pregnancies can lead to earlier detection and intervention for fetal complications.
- Advances in diagnostic tools and therapeutic options, like bipolar cord coagulation, offer better outcomes for complex twin gestations.
- This review underscores the importance of patient involvement in decision-making for invasive procedures, emphasizing personalized care in high-risk twin pregnancies.
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