recovery after childbirth
Refers specifically to the mother's physical recovery and convalescence following childbirth. Often used in the context of traditional postpartum care.
Since my recovery after childbirth isn't going well, I decided to rest at my parents' house for a while.
growth of a child
Describes a child's physical development and thriving, often used in older or traditional contexts. Modern Japanese more commonly uses 成長 or 発育.
This child's growth is fast; they've already started walking.