title: Vanishing twins: the frequency of spontaneous fetal reduction of a twin pregnancy.
abstract: This study examines the outcome of 126 twin pregnancies diagnosed by ultrasound examination at 6-16 weeks' gestation. Fifty-nine patients conceived by in vitro fertilization (IVF) and embryo transfer and had a routine scan. The 67 non-IVF pregnancies had a scan for other clinical indications including threatened abortion. When live twins were detected prior to 7 weeks'gestation, only 71% of pregnancies resulted in live twin neonates. Each fetus of a multiple pregnancy had a 19% chance of dying in utero or in the neonatal period of diagnosed prior to 7 weeks, and 11% if both were found to be alive between 7 and 10 weeks. The fetal loss rate was similar for IVF and non-IVF pregnancies.
authors.affiliation: Royal Women's Hospital, Melbourne, Australia.
authors.forename: A
authors.initials: A
authors.lastname: Sampson
authors.forename: L C
authors.initials: LC
authors.lastname: de Crespigny