Twenty-two selective terminations in multiple gestations were performed by a number of different methods. In 17 dichorionic pregnancies there was a successful delivery in surviving singletons or twins. In five monochorionic pregnancies undergoing selective termination there was a successful delivery in only one and a pregnancy loss in the other four. Six of the 18 delivered pregnancies were complicated by premature labor and delivery. Among the several methods used for selective termination, intracardiac potassium chloride injection appears to be the procedure of choice in dichorionic pregnancies.
PIP: Physicians selectively terminated 22 fetuses of multiple gestations between November 1983-August 1987. In the case of same sex twins, after initially identifying 1 fetus by amniocentesis as chromosomally abnormal, fetal blood samples were drawn for karyotyping 48-72 hours before selective termination to identify the affected fetus. These samples were repeated at time of termination to confirm termination of that fetus. Practitioners used ultrasound to perform all procedures, except hysterotomy, and to confirm asystole in the affected fetus and normal heart activity in the remaining fetus (es). 18 patients delivered normal infants, 6 of whom delivered at a gestational age of 37 weeks. Only 1 infant of the 5 monochorionic pregnancies lived. In this case, termination of the sibling fetus occurred via hysterotomy and the physician prescribed oral tocolytics for the mother. Procedures used and their results for dichorionic pregnancies follow. Potassium chloride injections into the heart or into the pericardial region of the chest resulted in a reduced premature labor rate (20%) than did cardiac puncture with air embolization (33.3%). This may be due to decreased intrauterine manipulation and decreased procedure time required to administer the potassium chloride injections. 1 exsanguination was to be performed, but the affected fetus died in the interim between fetal blood sampling and the scheduled day of confirmation. As this study confirmed, poor outcome of remaining normal fetuses is based on premature labor and monochorionic placentation. New techniques add to the many social and ethical considerations of selective termination, especially in those cases where the aborted fetuses are normal.