- Pertaining to the period immediately before and after birth. The perinatal period is defined in diverse ways. Depending on the definition, it starts at the 20th to 28th week of gestation and ends 1 to 4 weeks after birth. The word "perinatal" is a hybrid of the Greek "peri-" meaning "around or about" and "natal" from the Latin "natus" meaning "born."
* * *Occurring during, or pertaining to, the periods before, during, or after the time of birth; i.e., before delivery from the 22nd week of gestation through the first 28 days after delivery. [peri- + L. natus, pp. of nascor, to be born]
* * *peri·na·tal -'nāt-əl adj occurring in, concerned with, or being in the period around the time of birth <\perinatal mortality> <\perinatal care>
* * *adj.relating to the period starting a few weeks before birth and including the birth and a few weeks after birth.
* * *peri·na·tal (per″e-naґtəl) [peri- + natal] pertaining to or occurring in the period shortly before and after birth; variously defined as beginning with completion of the twentieth to twenty-eighth week of gestation and ending 7 to 28 days after birth.
Medical dictionary. 2011.