The birth of more than one baby or young animal from a single pregnancy.
 multiple births are more common than ever before
mass noun the use of these medications increases the risk of multiple birth
 Example sentencesExamples
-  The incidence of multiple births increases with the age of the mother.
 -  Multiple births can cause complications during pregnancy.
 -  Intrauterine insemination alone does not increase the risk of multiple birth.
 -  There was an increased risk to the babies' health because it was a multiple birth.
 -  All multiple births must be delivered in hospitals.
 -  During the pregnancy, they were told of the risks of proceeding with the multiple birth.
 -  In four generations, the family have not been able to trace any other multiple births.
 -  Doctors expect to see more multiple births as women wait until later in life to have children.
 -  Both multiple births were unaided by any sort of fertility treatment.
 -  The increase in multiple births due to fertility treatments has caused concern among doctors.