First Direct Evidence That Babies React to Taste in the Womb

A study led by Durham University in U.K. has provided initial evidence that unborn babies react to taste in the womb. This suggests that pregnant women’s eating habits might also influence the post-natal taste preferences of their newborns.

Durham’s Fetal Neonatal Research Lab took 4D ultrasound scans of one hundred pregnant women in the northeast of England who were between week 32 and 36 of gestation to see how their unborn babies responded after being exposed to flavors from foods eaten by their mothers.

This was examined by measuring frame-by-frame the facial movements of the fetuses to determine their responsiveness to flavors transferred via maternal consumption of a single-dose capsule of either carrot or kale.

The results showed that fetuses exposed to the carrot flavor showed more “laughter-face” responses while those exposed to the kale flavor showed more “cry-face” responses.

Exposure to just a small amount of carrot or kale flavor was enough to stimulate a reaction.

How unborn babies experience taste

Humans experience flavor through a combination of taste and smell, the university explains in an article. In fetuses, this happens through inhaling and swallowing the amniotic fluid in the womb.

Previous studies had already suggested that babies can taste and smell in the womb, but they were based on post-birth research strategies while this new study is the first to see these reactions prior to birth.

The full study, published in the journal Psychological Science, maintains that taste buds in human fetuses develop anatomically at eight weeks along in gestation and can detect tastants from week 14. Odor-active molecules can be also sensed from the 24th week of gestation.

Hence, unborn babies can detect flavors including tastants and odorants in the amniotic fluid in the last trimester of pregnancy.

Researchers at Durham University have now begun a follow-up study with the same babies post-birth to determine whether the flavors they experienced in the womb affect how they react to different foods.