Yes, I think it's possible. I have dreams all the time about friends' unborn AND born children. I am a firm believer in pre-birth communication and astral projection (leaving your body during sleep) - and I think the babies come visit me quite often. Usually they are around a few months old to a few years old, and they are either laughing or scared. The laughing ones just come around to say "hi there! Look at me! Woo hoo!" and get some snuggles. The scared ones need some hugs, and they seem to be frustrated at how small they are, and how dependent they've chosen to become by being reborn as infants. At least, that's my "take" on it all - it's more like measuring the emotions present as an instant snapshot rather than a movie. I have a couple who visit me quite regularly and I remember the dreams vividly the next morning. I still dream about my preschool kids, "my" kids, all the time. I don't doubt that we are connected in some special manner, by love, even though we live in different states and towns.
And pregnancy is such a magical time - I have no doubt that the little infant souls are checking out who will be in their lives and giving us the once over!