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The baby is 3 months old
Medical expert of the article
Last reviewed: 06.07.2025
A 3-month-old baby is a baby who brings more and more joy to his parents. He continues to develop intensively, but the most important thing he can do consciously is smile, recognizing familiar, dear faces. It is the smile of a three-month-old baby that causes endless delight and admiration. There is information, however, not confirmed either scientifically or statistically, that a baby's smile has more than 70 variations.
Obviously, there are many more ways to show parental joy, and a small hint of a child's smile is enough for them. In addition, the baby learns to react emotionally to the appearance of familiar people, he literally pleases those around him every day with his new skills and achievements, among which should be the following:
- A small child of 3 months perfectly recognizes everyone who is regularly with him in the house. This is, of course, mom and dad, possibly grandma and grandpa. The child willingly gives his smile to unfamiliar faces, because for him all people represent joy and comfort.
- A baby can show his character by crying, not related to hunger or an overflowing diaper. A child can be capricious when he is not given attention, protest against food that is unpleasant for him (complementary feeding).
- The baby begins to make sound combinations, “cooing”, as if talking to his parents.
- The child can reach out and touch rattles hanging in front of him.
- The baby can grab toys and even put them in his mouth.
- The baby can bend and unbend his fists, often pulling them into his mouth, as well as his legs, which he begins to see and study.
- If you place a three-month-old baby on his stomach, he should be able to lift his head and chest, using his arms as support.
- The baby is able to roll over onto its side on its own.
- If you take a child under the arms, he will try to rest his feet on the surface.
- The baby holds his head much better and turns it actively.
- The child reacts well to sounds and is able to show with his eyes and head turns that he has found the source of the sound.
A 3-month-old baby is a baby that has become much heavier than in the first month of its life. On average, it is considered that by three months a baby should gain from 800 grams to a kilogram in weight. The baby's height also increases - by 3-4 centimeters. The baby's respiratory system develops, digestion becomes more stable. It has been proven that by the third month, the area of the mucous inner lining of the stomach in a small baby increases almost threefold compared to the first month of life. All the reflexes that the baby received from birth (innate) are gradually replaced by skills and conditioned reflexes.
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Baby 3 months: routine and nutrition
The feeding schedule remains almost the same - eating every 3-3.5 hours, that is, 5-6 feedings. It is imperative to introduce a night break in feeding - this helps the mother get enough sleep and recover after childbirth much faster, and it is time for the baby to accustom its digestive tract to eating during the day. At this age, the child does not yet need complementary feeding, it receives enough nutrients from breast milk. After feeding, the baby needs to be accustomed to wakefulness to activate digestive functions, after an hour of quiet games, the child needs to be put to bed, sleep should last about three hours (2-2.5 hours). It is necessary to switch to four times a day sleep, and at night it is necessary to accustom the baby to a full sleep - at least 10 hours. Daily exercise in the fresh air remains mandatory, it is advisable to walk in any weather, of course, dressed adequately for temperature conditions.
Baby 3 months: vaccinations
During this period, the baby must undergo a rather complex vaccination, vaccinations against four serious, sometimes deadly diseases - tetanus, whooping cough, diphtheria, which can lead to suffocation, and poliomyelitis. The epidemic situation concerning these diseases is relatively stable throughout the world, but for reasons that are still unclear, there are periodic outbreaks of diphtheria or whooping cough. Of course, all vaccinations are not guaranteed to be 100% safe, and the child's condition after vaccination may be different. Vaccinations should be prescribed against the background of the baby's absolute health, in order to give the active immune system the opportunity to adequately meet strains of viruses or bacteria. Today, in pediatrics, it is customary to carefully examine a child before vaccinations, and prescribe tests to clarify the child's health.
3 month old baby: typical health problems
Babies of this age should not have any diseases or signs of them. But, unfortunately, absolutely healthy children are not often found in clinical pediatric practice today. Perhaps these disorders and signs of diseases can be explained by hereditary factors, since today even a healthy mother is a rarity. If the parents have latent or obvious chronic diseases, the baby can inherit the property and characteristics of the system or organ, but not the disease itself. More and more often, pediatricians record diathetic rashes in children at the age of three months, intestinal colic, which was rarely discussed about fifty years ago, has become almost inevitable. Both diathesis and colic are a violation of the digestive process, therefore, it is necessary to start solving the problem with nutrition, diet and its composition. If the child is breastfed for 3 months, the mother should adjust the diet. If the baby is bottle-fed, formulas should be selected more carefully and complementary foods should be excluded until the child reaches four months.
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