Multifetal pregnancy reduction

The number of multiple pregnancies has dramatically increased, mainly owing to the development of assisted conception techniques. In multiple pregnancies there is an inverse relationship between the number of fetuses, and the length of gestation and infant birth weight. Multifetal pregnancy reduction (MFPR), a process by which we can reduce the number of fetuses, has been proposed as an option in order to improve pregnancy outcome. It is performed usually in the first trimester, by transabdominal injection of potassium chloride into a fetal heart, under ultrasonographic guidance. A review of the literature suggests that MFPR reduces the risk of pregnancy loss and severe prematurity in quadruplets and higher-order pregnancies. The risk of miscarriage seems to be associated with the final number of fetuses. In triplets reduced to twins, severe preterm delivery rate is lower and gestation is prolonged in comparison to average figures for triplets reported in the literature. © 2004 Parthenon Publishing. A member of the Taylor & Francis Group