Human Development

What the Unborn Sense in the Womb

Interview With Dr. Carlo Bellieni
During its gestation the fetus is "already a member of the family, and company for the mother even before being born," says neonatologist Carlo Bellieni.
Dr. Bellieni [Department of Neonatal Intensive Therapy of the University Polyclinic Santa Maria Le Scotte of Siena] talked about his research on life-before-birth for his latest book "L'Alba dell'Io" (Dawn of the I), published by Società Editrice Fiorentina.
Q: Until the 1980s it was thought that the maternal uterus was a sort of strongbox for the fetus. What has changed since then?
Bellieni: Very much. Today we know that the fetus is a pluri-sensorial being whose senses enter into action with a pre-ordained sequence: first, tactility is manifested; then the chemical; the sense of balance; hearing; and finally sight.
The early development of the senses in the uterus has a double function: that of forming the central nervous system, providing stimuli which interact with the growth of groups of neurons, directing it on a physiological path, and of introducing the unborn to the exterior world — bringing about a kind of learning in the uterus.
Q: Is it true that the senses enter into action precociously before birth?
Bellieni: Already in the eighth week after conception the receivers of touch are present in the fetus in the area of the mouth, which later are extended throughout the whole surface of the body in a few months.

But it is around the 22nd to 24th week when the connections will be ready with the cerebral cortex. The fetus responds to the stimuli that come through the mother's womb.
Q: Tell us about the fetus' hearing and taste.
Bellieni: Toward the 25th week of gestation, the fetus has developed hearing. Within the uterus the mother's voice comes with much greater intensity than another's voice — or the father's! — and the fetus gets used to this voice, so much so that several experiments have shown us that the newborn is able to distinguish the mother's voice from that of a strange voice, just as it is able to distinguish the mother's scents.
This will serve to recognize the maternal milk, which has a taste and smell similar to the amniotic fluid which for nine months has soaked its tongue and lips.
Q: Does the fetus have memory?
Bellieni: Research was published in Pediatrics in 2001 which showed that at the moment of weaning the child prefers tastes that it perceived in the uterus in a certain period, although these tastes were not given to it during lactation. Therefore the fetus has memory.
This, which seemed to be only the prerogative of psychiatrists, today is the patrimony of the pediatrician to explain several phenomena.
We recently carried out a study on what happened to the children of ballerinas who during pregnancy did not stop dancing: They needed to be rocked to sleep more energetically than the others!
Moreover, what is it to rock the newborn to sleep if not to reconstruct that serene environment he had in the uterus: rhythmic movements, the mother's perfume, an indistinct voice but present and humming, darkness — but the presence of walls and limits that he would not find if left abruptly in a bed?
Q: Have you carried out other studies on the fetus' memory?
Bellieni: Yes, for example on short-term memory, demonstrating that the fetus gets used to external stimuli as a child that is already born.
We have used sonorous stimuli sent through the wall of the uterus and have measured echo-graphically how the fetus reacts, ill-at-ease, blinking his eyes and then how it gets used to the noise.
Q: Is it true that the fetus dreams?
Bellieni: Studies on the premature newborn give increasing data on the characteristics of sleep in the uterus.
In 2000, professor Rivkees of Yale University showed the presence of a day-night rhythm from the midpoint of gestation. Today we know that from the 28th week of gestation the phases of sleep can be differentiated. From the 30th week, active sleep is present, which is equivalent to an adult's REM sleep, when most dreams take place.
Therefore nothing prevents us from saying that in the uterus the fetus has all the "instruments" to dream: an appropriate cerebral electrical activity and the presence of stimuli that will make their contents.
Sleep is also most important in the uterus because the greatest proliferation of nervous cells occurs there, and the preferential production of certain hormones.
Q: Does the fetus feel pain?
Bellieni: It seems impossible, but the pain of the fetus and the newborn was acknowledged only at the end of the '80s.
Nevertheless, it is clear that our premature babies born at 23-24 weeks feel pain. And the hormonal changes after the painful stimulus have been demonstrated in fetuses of 20 weeks or slightly more.
On the very little ones born before their term, we have recently experimented with a system of analgesia based on non-pharmacological techniques of distraction. We were right.
The premature newborn feels pain, cries, but is also able to interact with the one near him, accepting being consoled and distracted, so much so that he/she no longer feels pain! A video of three American scholars on the fetus' crying may be downloaded online [see (].
Q: How does a child spend the day before being born?
Bellieni: The fetus has a world of sensations, but also of actions. The fetus responds in its own way to external stimuli. It is frightened if it hears noise; it responds to patting.
But it exercises itself for life in the open air: It does breathing exercises constantly, even when immersed in the amniotic fluid, and attempts have been registered to emit sounds visualizing the vocal cords.
It has hiccups and makes faces as though smiling or crying. Its movements respond to phases of calm or movement of the mother, and also of the amount of sugar the mother eats.
Q: What would you say in conclusion?
Bellieni: That the fetus is already a new member of the family and company for the mother even before being born.

[, ZE05100422 Rome, 4Oct05]