Baby’s sense of smell is one of her most developed senses at birth – when she was still only capable of seeing and processing things 8 to 12 inches away, she was already able to smell as well as you could, and in some specific instances, even better. By the time Baby is a few hours old, she can differentiate her mother’s scent from all other smells, as long as she has had some skin-on-skin-contact to learn it.
Baby‘s sense of smell isn’t the over-achieving sense out of nowhere, though – her ability to smell has been developing since her nasal cavity started to separate from her mouth at around 9 weeks of gestation, and has been fully functional since some time between 30 and 33 weeks of gestation.
For a long time, scientists believed babies in the womb had no sense of smell because instead of breathing air, they inhaled amniotic fluid. However, studies now show that newborns only a few hours old recognize the scent of their mothers’ amniotic fluid, proving that a sense of smell becomes fully developed in the womb and suggests that scent plays a part in the taste-preferences babies develop before they’re born, based on their mothers’ diets.