Expecting A Child

( the woman is pregnant so they are expecting that a baby will born ... )

Expecting a child is when the woman is pregnant and will give birth to a new baby. Example: "My wife and I are expecting our first child." Reply: "Congratulations!"

The woman or the couple who are getting ready ("expecting") to have a baby ("a child") are "expecting a child." Example: "You will need to take better care of yourself. You are expecting a child."