If you watch a new mom and her baby, it's easy to see that the little one responds to mother's touch.
That responsiveness actually begins before birth. Researchers in Scotland compared fetal responses when pregnant women spoke to their babies or rubbed their bellies. "Overall results suggest that maternal touch of the abdomen was a powerful stimulus, producing a range of fetal behavioural responses," the researchers write.
Scientists have studied how unborn babies respond to their mothers' voice, but whether, how and when they're affected by touch was much more of a mystery.
"I think the study gives us a bit of a better understanding to how fetuses respond to maternal voice versus touch and when they do so," says Erin Clark, MD, an OB-GYN at University of Utah Health. "They seem to differentiate between the two."
The researchers found that fetuses in the third trimester responded more to their mothers than those in the second trimester. The responses were different, with fetuses moving around more in response to touch and "quieting down" (their heart rates decreased) in response to their mother's voice.
"Early stimulation with voice or touch does seem to be getting through to fetuses," Clark says. "Parents want to know they're getting through to that little baby and responding in that way."
Clark says moms who already talk to or sing to their baby bumps might also want to consider rubbing their bellies to connect with the new family member while they're waiting to meet him or her.
"Touch can be a part of that," she says. "It's one of those ways you can connect with your fetus as early as the 21st week."