What are the differences between early embryonic death, mummy, stillbirth and abortion?

Embryonic death occurs before a fetus is formed (identifiable body parts) and this accounts for most losses (20-40%) in swine. Mummies are pigs that are lost after day 40 but before farrowing and the size of the mummy reflects when the loss occurred. Stillbirths are pigs that are lost around the time of birth and may be prepartum or intrapartum. Abortions are pigs that are expelled from the uterus before parturition.