P05.13: Selective reduction of conjoined twins at 13 weeks of a triplet pregnancy

Abstract

Advances surrounding the assisted reproduction has increased the number of multiple pregnancies. Monoamniotic twins can occur in about 5% of monochorionic pregnancies, and in about 1% of those the twins are conjoined. Pre-natal diagnosis is important to improve obstetrical management. A 37 years old woman was submitted to in vitro fertilization. Early diagnosis of a triplet gestation was made, two of them thoraco-omphalopagus and the other fetus, in another amniotic sac/placenta, was normal. After discussion, parents decided to being submitted to a selective reduction of the monoamniotic twins at 13 weeks, by the infusion of KCl in the heart of conjoined twins. The remaining fetus continued to develop and was born at 37 weeks, with a normal outcome in the perinatal period. In monochorionic twins there is about a 25% risk of death or neurological handicap when one of the fetus die. Although unknown risks of the selective reduction of the conjoined twins, parents were lucky in their decision. There are only four other cases reported in which dichorionic monoamniotic pregnancies with conjoined twins, that underwent selective termination or spontaneous embryo reduction to singleton in the first trimester, that resulted in term delivery of the normal fetus. We think that with new interventions (occlusions of the umbilical cord by laser or diathermy) safer terminations may be possible.