Humans have five basic senses: Sight, smell, taste, hearing and touch.
You may be wondering just when, during your pregnancy, your tiny baby can start feeling, smelling, tasting, hearing and see. You will be surprised to know that it is a lot earlier than you think!
Your baby’s senses begin to develop from the moment of conception with all the senses established by week 8 (gestational age) but maturing at varies rates.
What this means is that although the senses begin to develop very early on, they only really start functioning properly later in your pregnancy.
What is The First Sense a Baby Develops in The Womb?
Before you even knew you were pregnant, at just 3 weeks after conception, your baby’s first sense to develop is the sense of touch.
The skin, which contains millions of sensory receptors, is the sensory organ for touch.
Research done by Montagu (1978) with a single light hair stroke on the embryo, showed that just before 8 weeks gestational age, “the first sensitivity to touch manifests in a set of protective movements to avoid a mere hair stroke on the cheek”.
Skin sensitivity then extends to:
• The genital areas by 10 weeks gestational age,
• The palms by 11 weeks gestational age,
• The soles of the feet by 12 weeks gestational age,
• The abdomen and buttocks by 17 weeks gestational age and
• The entire body with the exception of the top of the head by 32 weeks gestational age.
Your baby uses this newfound sense of touch to explores his/her environment in the womb by stroking his or her face, sucking on a thumb, touching the rest of his/her body, touching the uterine wall and the umbilical cord.
Another study, using 4-D scans, published in 2013 by Durham and Lancaster universities “found, for the first time, that a fetus was able to predict, rather than react to, his/her own hand movements towards his/her mouth as they entered the later stages of gestation compared to earlier in a pregnancy”.
This showed that, in the womb, babies open their mouths before bringing their hands to their mouths.
Touch, the strongest sense at birth, is a critical survival sense and is the main way in which infants learn about their environment and bond with other people.
Most of what a newborn learns about the world is learned through touch—holding, caressing, dressing, diapering, cuddling, etc.
Can Your Baby Smell While Still In The Womb?
Initially researchers thought that because smell depends on air and breathing, a fetus could not smell in the womb, but subsequently research has shown that the sense of smell is very strong at birth and that this may come from smells learnt in the womb.
Your baby’s nasal cavity is fully formed and the chemoreceptors for smelling are ready as early as 9 weeks gestational age, but it is only at 13 weeks gestational age that the olfactory nerves (used to recognize smell) connect to the brain.
Although everything is functioning at 13 weeks, in the womb, your baby suffers from an extremely stuffy nose due to giant plug of tissue blocking his/her nasal cavities until about 28 weeks gestational age. So it is only after 28 weeks gestational age that your baby can smell and respond to odors through the amniotic fluid passing through your baby’s mouth and nose.
When your baby is born, his/her sense of smell is set to discover the world. This is seen soon after birth, when your baby is placed on your chest, he/she will instinctively seek out your breast milk and latch on.
Can Your Baby Taste What You Are Eating While Pregnant?
Just 8 weeks after conception, your baby is beginning to develop taste buds and by 13-15 weeks gestational age your baby has taste buds similar to an adult’s.
Amazingly, the amniotic fluid (that surrounds your fetus in the womb) can smell strongly of strong tastes from a mother’s diet such as curries, garlic, coffee, vanilla, carrot, aniseed and mint.
Ultrasound scans show that a foetus can swallow liquid or suck as early as the 5th month.
So, during the second trimester, your unborn baby will likely start sampling the flavor buffet in the amniotic fluid – flavored by the food and beverages you have consumed in the past few hours.
Based on the amount of swallowing that takes place when exposed to sweet, sour and bitter tastes, studies have shown that your unborn baby already has a sweet tooth – preferring sweet tastes over bitter and sour ones.
It is reckoned that at 21 weeks, a fetus can discern full-on flavors in the amniotic fluid using his/her senses of smell and taste. During the last trimester, the fetus is swallowing up to a liter a day of amniotic fluid!
Have You Ever Wondered If Your Baby Can Hear Sounds in the Womb?
The hearing organs start forming when your tiny embryo is just 3 weeks old, starting at the inner ear and slowly building up to the ear canal, until eventually you’ll be able to see the outer ears on an ultrasound image.
By week 16 (gestational age), although the bones and tissue that make up your baby’s ears are in place, it is still a few more weeks before the nerves conducting sound become functional, at around 20 weeks gestational age.
To begin with, your unborn baby only hears low noises, such as the whooshing noises as the blood moves through your blood vessels, gurgling noises from your stomach, and your heartbeat, but as development continues he/she starts to hear higher pitched noises too.
During your second trimester, around 23/24 weeks gestational age, you’ll begin to notice that your baby reacts to certain noises and may jerk or even begin to hiccup after hearing a loud sound.
From the sound of your voice, barking dogs and other loud, startling noises in your home, your baby starts to make sense of a lot of the outside world.
Eventually he/she will be able to recognize and distinguish some of them. As your pregnancy progresses, the volume of the sound required for your baby to hear and respond also gets progressively lower.
While your baby will already have well-functioning ears at birth, they’ll continue to develop for the first six months, hearing a wider range of frequencies.
Can Your Baby See in the Womb?
Vision is the last sense to develop in your unborn baby.
This is because for about the first 26 weeks of your pregnancy, your baby’s eyelids remain closed for the retinas to fully develop. Around week 26, your baby’s tiny eyelids open and even begin to blink!
At 6 months babies can distinguish light in the womb.
At 32 weeks gestation your baby can track a bright torchlight shone and moved across your pregnant belly.
By week 33 gestational age, the pupils of the eye can detect light and constrict and dilate, allowing your baby to see dim shapes.
In the last trimester of pregnancy, rapid eye movements (REM) have been seen in the fetus (in adults, these occur when we are dreaming). Perhaps your baby is dreaming too.
Newborns have all the eye structures necessary to see, but they still need to learn to use them by developing skills such as focusing, teaming their eye movements, recognizing depth, developing eye-hand coordination, and making spatial judgements.
According to the American Optometric Association, at birth and up to about 3 months of age, your baby’s eyes cannot focus on objects more than 8 to 10 inches (20 to 25 cm) from his/her face and can only see in black and white and shades of grey.
By 8-12 weeks of age, infants should start to follow people or moving objects with their eyes. It is generally believed that infants have good color vision by five months of age.
By the age of 6 months, your baby can see more distinctly and move his/her eyes quicker and more accurately to follow moving objects and visual acuity improves from about 20/400 at birth to approximately 20/25 (20/20 is considered normal vision).
You can make use of the above knowledge and begin to stimulate your baby’s developing senses of hearing, smell, sight, touch and taste by interacting with your unborn baby. For example:
• Take time out every day to massage your pregnant belly – not only will it help you to relax, but it will stimulate your baby through touch.
• Talking or singing to your baby – read stories and play music.
• Maintaining a healthy diet.
It’s never too early to start bonding with your baby!