Postnatal

1. (of a baby) after being born, of or pertaining to the period immediately after birth
2. (proscribed) (of a mother) after giving birth

In careful usage postnatal refers to the baby, after being born, while the mother, after giving birth, is referred to as postpartum. In casual usage postnatal may be used for both.

(give birth): postpartum

prenatal

(be born): postpartum