Fetal behavior during pregnancy

In short: Four-dimensional ultrasound reveals the hidden world of the baby in the womb. This article describes how the baby develops and behaves during pregnancy, from the first divisions of the cells to movements that can be watched on the scan.

Fetus ….. World of secrets that can be discovered by four dimensional ultrasound

Fetal life starts by the fertilization of ova by sperm followed by division of the cells that will increase in number and the organs start to be formed and start functioning forming in that way a human being that is modest in size and complicated in development and behavior that use the uterus as a place of residence until it’s time for him to meet the outside world!!!

The four dimensional ultrasound has opened a window in to the woman’s uterus to discover the secrets of that human being and to answer a lot of questions that surround him and that stunned the scientists for long period of time and that stimulated the curiosity of parents such as: when the fetus start moving? What are that movements? And when does the mother feel them? And does the fetus have senses? Does he feel pain? Does he sleep? Does he dream? Does he have the ability to learn and does he have memory? Is stimulating the fetus is a healthy phenomenon? A lot of questions that were impossible to be answered without the massive development that has occurred on the ultrasound devices.

The first fetal movement-that doctors can observe- starts between the seventh week and the middle of the eighth week and it can’t be felt by the mother. And it’s a sudden movement that continues for one to two seconds as if the whole body of the fetus that is around 2 cm in length in that period of time is moving and this movement is preceded by his heart beats that can be monitored during the 6th week. And from that moment the practical fetal life starts inside the uterus of his mother and every day the fetus grows up is associated with an increase in complexity of his movements and his organs start functioning gradually. Those movements take different shapes and the scientists thought for long period of time that those movements start as a reaction but it was found later on that they are spontaneous and unplanned movements that develop gradually with time until the fetus start to flex and extend his arm then flex and extend his limps and moving his whole body without the appearance of the movements of limps. And that overall body movement increase in strength from the 8th week- when it starts- until the 12th week so it ranges between strength and weakness. But the greatest thing which distinguishes it is that it gives this little creature an intimation of high confidence that he keeps for himself always.

And one of the funny movements that can be monitored and that start in the 9th week is the hiccup which is associated with a contraction in the diaphragm and it can be monitored by the doctors in the abdominal and chest movements, and the hiccup usually is repeated in a short and fixed periods of time and it rarely happen for one time only.

On the other hand the mouth movements are various and start by opening and closing the jaw and by chewing like movements since the 10th week and then yawning in the middle of the 11th week that start by opening his mouth and relaxing the tongue and staying in that situation for 1 to 8 seconds and it might be asked by some people what make the fetus to yawn?!

The exact reason for yawning is still not known, even in adults. The old idea that we yawn because the brain lacks oxygen has not been confirmed, and the fetus does not breathe air but receives its oxygen through the placenta. In the fetus, yawning is thought to reflect the normal development of the brain and of the cycles of sleep and wakefulness. Yawning is a normal, common behavior seen in healthy fetuses, and it becomes less frequent as the pregnancy approaches term.

Sucking and swallowing can be noticed in the middle of the 12th week and at that time the fetus can be seen sucking his finger or putting his hand on his face, opening and closing his fingers, putting one hand over the other and moving his feet, making acrobatic movements trying to attract the attention of his parents and to deliver a message from his little surrounding that he is he is a human being with an individual personality and special needs, even if it was before the 1st trimester of the pregnancy. And as the fetus is approaching the expected date of delivery, his behavior becomes as close as possible to the behavior of the newly born baby. And in spite of all those movements that start early in pregnancy, the mother doesn’t feel them until the 16th to 20th week of pregnancy. And the proportion of movements that are felt by the mother is negligible when compared to the overall movements of the fetus that sleeps and wakes up and moves on a rate of 50 movements per hour. And he goes through the same sleep stages of us, he feels sleepy and goes in a deep sleep and he has dreams during his sleep that can make him smile or annoyed and in many times he might feel angry and frown his eyebrows, and this can be seen during sleep and wakefulness.

Sleep stages change and take its final shape with the fetal brain development until it becomes the same as in the new born when approaching the time of delivery. And it’s worth mentioning that the fetus in the 32 weeks sleeps in 85-90% of his day. It remains to say that the movements of the eye lids appear between the 18th and the 20th weeks but it can’t be distinguished easily by the doctors.

The most complicated question is that does the fetus have the same senses that we have?! After the researches that was done by the scientists the answer was yes. And the first sense that appears in the fetus is the sense of touch that starts in the face in the 7th week and then it moves gradually to the rest of the body. In the 14th week of pregnancy the sense of taste starts so we find the fetus sucking and swallowing and the strangest thing is that the speed of swallowing of the amniotic fluid depends on the taste of this fluid that change according to the type of the mother nutrition. And it was found by the scientists that the swallowing becomes faster when the taste is sweeter!!

The sense of hearing in the fetus starts earlier than many people think: the first responses to low-pitched sounds can be seen from about the 19th–20th week, and by about the 25th week most fetuses respond to sound. By the time of birth the baby has already had several months of experience hearing his mother’s heartbeat, the blood flow and the sounds of her stomach and intestines, as well as voices that reach him through the abdominal wall and the uterus, although his hearing will continue to mature after birth. And the fetus can be monitored by the ultrasound vibrate strongly in response to the powerful acoustic stimuli. He even born preferring the voice of his mother and there are many cases recorded when the fetal heart beats became slower by hearing the voice of his mother or a story by a familiar voice to him as he doesn’t only hear the voices, he distinguishes them too and this is a proof that the ability to learn and the memory are formed in the human before he meets the outside world. And those conclusions by the scientists came out by the prolonged observation of the fetuses within the researches, in addition to the monitoring of the fetus behavior, as a reflex to the voice was seen in the 24 weeks fetus.

The vision is the last sense formed in the fetus and this sense was discovered by the Japanese scientists by shedding a strong light to the abdomen of the mother and they registered a response from the fetus. However, most scientists advised not to do such experiences on the fetuses before he becomes ready to receive such stimulants. In premature babies, damage to the retina (retinopathy of prematurity) is mainly related to the immaturity of the eye’s blood vessels and to oxygen levels, which is why neonatal units carefully control the oxygen given; studies have shown that reducing light exposure does not prevent it. For example, the brain of the fetus during the 6 months of pregnancy is not ready to receive or translate the signals of the eyes which affect the fetal brain development.

In general, the scientists are against the external influences that are over expected in all its types the audio, the visual or the sensual effects, that exceeds the limits of the short, quiet conversation and the story telling for short periods of time. Because all those influences have an effect on the fetal life in terms of sleep and alertness which affects the brain and nerves development and thus will give an adverse results to that expected by the parents like the increase in the mental development of the fetus in the future. And the best way to achieve this goal is by providing a uterine environment that is free from toxic materials for a mother without any psychological pressures and to have a healthy nutrition. Scientists have shown that a child’s intelligence depends on both genetic factors and the environment, including the environment inside the uterus, so avoiding smoking, alcohol and harmful substances and having good nutrition are important for the baby’s brain development.

On the other hand, the fetus shows reflex reactions to touch and needles from early in pregnancy: if touched by a needle during a procedure, it may withdraw, and studies in London found a rise in stress hormones (such as beta-endorphin) when the fetus was exposed to a needle. However, most scientific bodies (such as the RCOG) believe that the nerve connections needed to consciously feel pain are not formed before about 24 weeks of pregnancy. And this is the result of experiments that done by scientists in London to prove that the enfant can feel pain after this fact has been denied by the embryos surgeon for long period of time. It remains to say that crying-like movements (mouth opening, chin trembling and deep breathing movements) have been recorded on ultrasound in fetuses in the last third of pregnancy.

How this test is performed is described in our article on amniocentesis during pregnancy.

After all what mentioned above, everything we see by a 4 dimensional ultrasound can be explained, so this tiny creature has an independent personality that has its special hallmark that gives an inspiration of what he will be in the distant future.

And the most beautiful thing that can be seen by a 4 dimensional ultrasound is twin playing or awakens one another or even hitting each other… it is a world full of secrets.

Images displayed are for infants of varying ages that was captured by a 4 dimensional ultrasound in Doctor Najeeb Layyous centre which is located in Amman- Jabal Al-Hussein- Next to Amal Hospital.

Dr Najeeb Layyous F.R.C.O.G

Consultant Obstetrician, Gynecologist and Infertility Specialist