Lars B. Olding has written:

'Bacterial infection in cases of perinatal death' -- subject(s): Bacterial diseases, Diseases, Fetus, Perinatal death

The term puerperal infection refers to a bacterial infection following childbirth.

HPV appears to be transferred from the mother to the infant during the birth process.

Approximately 20,000 infants are born each year to mothers who test positive for the hepatitis B virus.

That is the correct spelling of the adjective "perinatal" (around the time of birth).