MULTIFETAL PREGNANCY REDUCTION OF BOTH FETUSES OF A MONOCHORIONIC PAIR BY INTRATHORACIC POTASSIUM-CHLORIDE INJECTION OF ONE FETUS

The purpose of this study was to determine if a monochorionic pair of fetuses in a higher-order multiple gestation can be reduced by injecti ng only one fetus with potassium chloride. Three quadruplet and two qu intuplet gestations, each with a monochorionic pair of fetuses, were r eferred for pregnancy rejecting-injecting one of the monochorionic pai r with potassium chloride. Patients returned for a follow-up sonogram within 1 week of the procedure. The reductions were performed at an av erage 12.1 weeks' gestation, with a range of 10.7 to 14.0 weeks. Follo w-up scans 4 to 7 days after the procedure showed that both monochorio nic fetuses were dead and all other fetuses were alive. One quintuplet pregnancy underwent a second reduction procedure to twins. One quintu plet and two quadruplet pregnancies that were reduced to twins resulte d in the birth of live twins between 30.8 weeks and 36.8 weeks' gestat ions. The third quadruplet pregnancy reduced to twins is still ongoing ; the mother is pregnant with twins at 20 weeks' gestation. The quintu plet pregnancy reduced to triplets resulted in delivery of Live triple ts at 24.1 weeks' gestation, but two of the neonates died in the first few days of life. Reduction of both fetuses of a monochorionic pair i n a higher-order multiple gestation can be accomplished by intrathorac ic injection of potassium chloride into only one of the pair.