Dichorionic multiple gestations
Selective termination can be easily carried out in dichorionic
gestations by the transabdominal percutaneous
procedure.39 Under ultrasound guidance, the
intracardiac injection of KCl is given to the targeted fetus using a 20
or 22-gauge needle until asystole is confirmed.
Evans40 published the largest multicenter series on
outcomes of ST in dizygotic pregnancies for structural or chromosomal
anomalies. They reported loss rates with gestation of procedure with
rates of 5.4% at 9-12 weeks, 8.7% at 13-18 weeks and 9.1% at
>25 weeks, although these did not reach significance. The
mean gestation at delivery was 35.7 weeks with a liveborn infant in
>90% of cases. They concluded ST, in the most experienced
hands, can be technically performed in all 3 trimesters (if legal) with
good outcomes in >90% of cases.
This report was followed by several single-center
series41-43 which confirmed ST in DC pregnancy with
discordant anomaly to be a safe, feasible and effective option. With
experience, the procedure-loss rate is reported as 4% and mean
gestational age at delivery as 38 weeks.