From Longman Dictionary of Contemporary Englishbe with childbe with childold useBABY/HAVE A BABY to be pregnant → child
Examples from the Corpus
be with child• Because our dear Claire is with child by Byron.• I wonder how good he was with children?• It was for this reason that I had Zowie because I could see how he was with children.• The man had run off and I was with child.• And if he were mistaken, it was just possible that the lass was with child.• The main problem is with children diving on the floor which can lead to some one getting hurt.• He must have noticed that she was with child.• When friendships finally became possible for him they were with children of the lower orders. 