title: [Difference between perinatal mortality in multiple pregnancies obtained spontaneously versus assisted reproduction].
authors.affiliation: Departamento de Ginecología y Obstetricia, Unidad Médica de Alta Especialidad, Hospital de Especialidades Núm. 23, IMSS, División de Ciencias de la Salud, Universidad de Monterrey, NL.
authors.forename: Yazmín
authors.initials: Y
authors.lastname: del Rayo Rivas-Ortiz
authors.forename: Ricardo Jorge
authors.initials: RJ
authors.lastname: Hernández-Herrera