Managing twins discordant for fetal anomaly
M A Rustico1, M G Baietti, D Coviello
1University of Milano, Department of Obstetrics and Gynaecology, Ospedale V. Buzzi, Milano, Italy.
Prenatal Diagnosis
|September 20, 2005
Summary
Selective termination in twin pregnancies with fetal anomalies depends on chorionicity. Dichorionic twins allow KCl injection, while monochorionic twins require umbilical cord occlusion, with bipolar cord coagulation yielding 70-80% survival rates.
Area of Science:
- Perinatology
- Maternal-Fetal Medicine
- Reproductive Medicine
Background:
- Twin pregnancies exhibit a higher incidence of structural anomalies than singleton pregnancies.
- Selective termination is considered for anomalies affecting only one fetus in 1-2% of twin pregnancies.
- Chorionicity is a critical factor in determining the method for selective termination.
Purpose of the Study:
- To outline the distinct approaches to selective termination in twin pregnancies based on chorionicity.
- To detail the techniques for achieving fetal demise in dichorionic and monochorionic twins.
- To report the efficacy of bipolar cord coagulation in monochorionic twin selective termination.
Main Methods:
- Review of techniques for selective termination in twin pregnancies.
- Description of KCl injection for fetal asystole in dichorionic twins.
- Explanation of bipolar cord coagulation for umbilical cord occlusion in monochorionic twins under ultrasound guidance.
Main Results:
- In dichorionic twins, KCl injection into the affected twin's circulation is safe due to absent placental anastomoses.
- In monochorionic twins, complete occlusion of umbilical arterial and venous flow is essential to prevent complications.
- Bipolar cord coagulation demonstrates a 70-80% survival rate for the co-twin.
Conclusions:
- Selective termination strategies must be tailored to chorionicity.
- Bipolar cord coagulation is an effective method for selective termination in monochorionic twins.
- Careful technique selection is crucial for optimizing outcomes in anomalous twin pregnancies.
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