Our psychologists have shown the first direct evidence that babies react differently to various smells and tastes while in the womb by looking at their facial expressions.
Durham's Fetal Neonatal Research Lab led on the study which took 4D ultrasound scans of 100 pregnant women who had taken either carrot or kale capsules beforehand.
The researchers then looked at how the fetuses reacted.
Other studies have suggested that babies can taste and smell in the womb, but they are based on post-birth outcomes while our study is the first to see these reactions before birth.
Laugh and cry-face responses
Fetuses exposed to the carrot flavour showed more "laughter-face" responses while those exposed to the kale flavour showed more "cry-face" responses.
Exposure to just a small amount of carrot or kale was enough to stimulate a reaction.
Humans experience flavour through a combination of taste and smell. In fetuses this happens through inhaling and swallowing the amniotic fluid in the womb.
Healthy eating habits
The findings could further our understanding of the development of human taste and smell receptors.
The researchers also believe that what pregnant women eat might influence babies' taste preferences after birth and potentially have implications for establishing healthy eating habits.
They have now begun a follow-up study with the same babies post-birth to see if the influence of flavours they experienced in the womb affects how they accept different foods.
