Overall, the team found that mothers talked to their babies about three times as much as fathers did, even though the recordings were done when both parents were around. (sciencenews.org)
You'll also notice that you (and most people, by the way) tend to use higher tones when talking to a baby. (babypreppers.com)
It's natural to start talking to your baby as soon as it's born.... (playconnectgrow.org)