Postpartum mania?

Is there such a thing as post partum mania or post partum manic depression? My wife just gave birth to a beautiful baby girl last week and we are home and everything is good but my wife is behaving really strangely. Like for the last couple of days she is humming with energy and doesn’t seem to need sleep and can’t stop talking. Her ideas are just bubbling out and they aren’t really making a lot of sense. I had a friend with bipolar who killed himself when I was a teenager and this is how he used to act when he was manic. I am worried but she does seem to be very happy so I don’t know if I need to be concerned or not. Do I?