When does the sense of smell develop in a fetus?

Dr. Michael Roizen, MD
Internal Medicine
It used to be that scientists believed fetuses had about as much of a sense of smell as they had a sense of fashion; that's because smelling typically depends on such basics as air and breathing. Now, though, it's believed that amniotic fluid jets though the nasal and oral cavities to actually help a fetus smell. That ability starts at about 30 weeks; before that time, tissues plug up the nasal cavities.

The sense of smell begins developing much earlier, as olfactory epithelial cells form in a fetus at 9 weeks along with nostrils. These cells connect to molecules that bind with the olfactory nerve (which leads to the brain).

After your baby develops a sense of smell, he can actually smell everything that you eat or inhale. The lesson: Mom should eat what she wants her baby to like to smell.
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.