mortality around the time of birth, conventionally limited to the period from 28 weeks' gestation to 1 week postnatal.
per·i·na·tal mor·tal·i·ty
(peri-nātăl mōr-tali-tē) Death around the time of birth, conventionally limited to the period from 28 weeks' gestation to 1 week postnatally. AcronymsSeePNMThesaurusSeeneonatal death