I suppose you could say this, but it's not clear and doesn't sound at all natural. As it's written, we might even conjecture that she is a delivery agent and someone else is the recipient. Moreover ,this type of in-wedlock birth is usually not commented on. It would be more usual to hear that she will deliver a child whose father is not her husband. Of course I am making these remarks in a vacuum, as you've provided us with no context.