When the baby’s 5 senses develop in the belly

When does the fetus start hearing sounds? When does he start seeing anything? Do you feel the “taste” of the amniotic fluid”? Touch and smell when they are formed?

All of us mothers ask ourselves over the course of the nine months what life inside the belly can be like. Intrauterine life despite the closed environment is full of stimuli that arrive in a very muffled and in a certain sense filtered way and a recurring question concerns the development of the child’s 5 senses.

If you swim and have dipped your head underwater you know that sounds come in very differently (this is because sound waves in water travel much faster than in air, but our auditory system is built to hear sound waves better airborne).

The fetus uses the senses that are gradually being refined to collect and process information, and already at 20 weeks of pregnancy its nervous system is developed in such a way as to already allow it to kick and communicate with the mother.

Gradually touch, sight, hearing, taste and smell are stimulated by everything that happens in the mother’s body and by the sensations that arrive from the outside.

What the mother eats, how much she rests, how she reacts to various situations, everything is transmitted to the fetus. For this reason, once the baby is born, the mother’s voice will be familiar to him as well as the foods she will receive through breastfeeding and the music you have listened to and continue to listen to.

How the fetus “listens” to the mother

The child notices every change that takes place in the mother’s life, in her daily life.

How much she rests, how much she’s on the move, and the different degrees of noise she’s exposed to.

If the mother is under stress her body releases a hormone, cortisol (also called the stress hormone), and the fetus responds to these changes by regulating its cortisol levels.

What was discovered during a study regarding mother’s sleep-wake rhythms is also very interesting.

It has been seen that mothers who get up early in the morning tend to have children who wake up early, while those who go to bed late tend to have children who fall asleep late.

Around the 32nd week of pregnancy, the baby has generally developed 4 distinct types of activity: active sleep, peaceful sleep, active wakefulness, peaceful wakefulness.

The active sleep phase is similar to the REM phase,

Up to the 32nd week the baby spends a lot of time in the active sleep phase but then begins to spend more time awake in the active or quiet phase.

It is thought that the more regular and repetitive the mother’s habits are (sleeping, eating, exercising or relaxing), the easier it will be for the baby to develop their habits after birth.

The sense of touch

Touch is the first sense to develop in the fetus. It begins to form between 7-8 weeks of pregnancy when it begins to move.

The sense of touch begins with the development of sensory receptors in the face, mainly on the lips and nose. Over the next few weeks touch receptors begin to develop on other parts of the body.

Around weeks 10 and 11 the palms of the hands begin to become sensitive and with them they can “feel” the face, although they are inclined to move away from the stimulus if they touch the cheek.

They have little movement control at first but towards the end of pregnancy they tend to move closer to touch.

This may be a sign of the sucking reflex  essential for breastfeeding: if you stroke a baby on the edge of the mouth or on the cheek, he will tend to turn towards the stimulus ready to suck.

By 12 weeks the feet become sensitive.

Towards the 14th week the whole body of the fetus responds to tactile stimuli and as the space becomes more restricted in the uterus, the more frequently the cord will touch the baby.

4D ultrasounds often show babies “playing” with the umbilical cord.

Just as newborns tend to use their mouths to explore everything in the first few months, so even in the belly they put their fingers or toes in their mouths. They probably enjoy thumb sucking even if they haven’t yet associated the action with a consolation to hunger.

As the birth approaches, the fetus is slightly squeezed by Braxton Hicks contractions . In addition to preparing the uterus for birth, it seems that they also serve to stimulate the senses and the brain of the unborn child.

Brain scans on unborn babies suggest that fetuses don’t perceive pain until after 30 weeks , when somatosensory neural pathways finish developing. However, by the middle of the third trimester, the fetus is able to feel a full range of sensations, including heat, cold, pressure and pain throughout the body.

Hearing

It is probably the most studied sense of all because it is also the easiest to stimulate before birth. The first studies on the subject date back to the 80s when it was demonstrated that children hear while they are in the womb and are able to distinguish and identify some patterns.

In a classic study, DeCasper and Spence (1986) asked pregnant women to read aloud from Puss in the Hat during the last six weeks of their pregnancy. After birth, infants were found to show a preference for this reading presumably based on their prenatal exposure.

Since these initial studies, more research has been published suggesting that fetuses are able to hear and even learn in the womb.

Babies react to noise around 24 weeks when the tiny bones in the ear canals harden and start working together.

The uterine environment is rich in sounds or coming from within such as the heartbeat, intestinal peristalsis or the sound of blood pumping through the umbilical cord.

The noises coming from outside reach the child in a very muffled way.

Many sound waves are bounced directly off our bodies, others absorbed by tissue and skin. High-frequency sounds are bounced back more easily while low-frequency sounds get through to the baby. For this reason, the fetus can probably hear the father’s voice quite easily.

The view

From around 27 weeks the baby opens and closes his eyes but sight will be the last of the 5 senses to mature during intrauterine life.

Everything is quite dark but if mum is at the beach in a bathing suit she can probably see an orange glow.

She probably can see the tone of the glow rather than the color because the baby’s vision in the womb is thought to be black and white. Color perception is thought to develop around 2 months after birth and this is why some games for toddlers are created in black and white to make it easier for the child to see them in more detail.

Although it is dark inside the uterus, human skin lets light through and provides some illumination for the developing fetus. According to psychologist Vincent Reid of Lancaster University who has studied this problem, the womb can be a surprisingly bright place, “analogous to being in a room where the lights are off and the curtains are drawn.”

Based on this premise, Reid and his colleagues studied the reaction of third-trimester fetuses to light-spot patterns. The babies’ reactions to different light patterns were monitored using high-definition ultrasound. The researchers found that the fetuses were about twice as likely to follow the movement of dot patterns that resembled a human face, the same pattern and preference that has been demonstrated in babies after birth.

This suggests that our preference for human faces may be innate and not simply the result of experiences that occur after birth. It also clearly demonstrates that the fetus is actively responding to the outside world long before it is born.

Smell and taste

Taste and smell are intrinsically intertwined because our sense of taste is actually 90 percent made up of smell. Some aromas, such as vanilla, carrot, garlic, anise and mint, have been seen to be transmitted into the amniotic fluid, where babies usually live and drink several centiliters a day.

From about 12 weeks of pregnancy, the baby begins to swallow amniotic fluid.

This liquid brings with it the flavors and smells of the food that mom eats.

Around the 35th week the taste buds are developed enough to recognize the flavors of what mom eats.

Some studies have shown that fetuses start to have their culinary preferences already during life in the belly. For this reason it is important to vary foods during pregnancy so that the baby begins to get used to a variety of flavours.

To test this theory, one group of pregnant women were asked to drink carrot juice every day while pregnant, while another group was told to avoid it completely. Once the babies started eating solid foods, the researchers fed them cereal made with water or carrot juice. They found that babies exposed to carrot in amniotic fluid ate more carrot-flavored cereal.

As far as the sense of smell is concerned, this is already well developed at birth. It has been shown that as early as three days old, babies recognize the smell of their mother’s milk.