Top 6 Stages of Child Development

The baby teeth stage spans from ages 1 to 6. Compared to the breastfeeding stage, growth slows down, and bodily functions gradually become more refined. Motor skills develop rapidly.

Mentally, children begin to show strong development, with an eagerness to learn, curiosity, and a tendency to make observations about their surroundings. Therefore, the environment plays a significant role in their mental development. The central nervous system develops, especially speech, and children become more receptive to education, often starting school by the end of this stage.

The adolescent stage spans from ages 7 to 15. During this time, the structure and function of a child’s body parts are fully developed, resembling that of an adult. Children at this stage have the ability to absorb knowledge quickly, think critically, and make judgments, fostering intellectual growth.

From the age of 10 and especially during the prepubescent years, children begin to recognize gender-specific psychological and physiological differences, and their physical development accelerates.

Girls typically begin puberty between the ages of 9 and 12, and it usually ends around 17 to 18 years old. Boys experience puberty a bit later, starting between 10 and 12, and finishing around 19 to 20 years old. During this stage, children experience rapid growth and significant changes in their psychological and physiological states. Hormonal and reproductive activities dominate, and reproductive functions reach maturity.

Due to the significant psychological and physiological changes, mental and hormonal development can be unstable, which makes children more prone to mood swings, optimism, and disappointment. As a result, they may engage in impulsive behaviors such as suicide or criminal acts. This period also increases the risk of mental disorders and cardiovascular issues.

The fetal stage, also known as the development period in the womb, begins at conception and ends with birth. The typical duration of this stage is 280 to 290 days, calculated from the first day of the last menstrual period. This period is divided into two phases: The embryonic development phase lasts for the first three months and focuses on the formation and differentiation of organs (organogenesis). By the eighth week, the embryo weighs around 1g and measures 2.5cm; by the twelfth week, it weighs 14g and is about 7.5cm long. During this phase, the fetus gains little weight and mostly increases in length. By the end of this period, all the essential organs have developed to form a fully-formed human. Exposure to harmful substances (such as dioxins, viruses, or certain medications) can interfere with organ formation, potentially leading to birth defects or deformities.

The development of the fetus during this stage is closely linked to the health and nutrition of the mother. It is crucial for the mother to manage the pregnancy well, identify any health issues early, and seek treatment as needed.

The newborn period starts from the moment the baby cries at birth until four weeks after delivery. At this stage, the baby has started adapting to life outside the womb. The first breath is taken as the baby cries. Immediately after birth, the circulatory system begins to function, replacing the placental circulation.

The digestive system also begins to work, as the baby starts breastfeeding, swallowing, and absorbing the mother's milk. The baby's nervous system is still immature, so all stimuli are overwhelming, causing the baby to sleep most of the time. Other organs also start functioning and adapting gradually. Additionally, due to the environmental changes, the baby experiences some physiological phenomena like jaundice, skin peeling, physiological weight loss, temperature fluctuations, and umbilical cord shedding.

The breastfeeding period begins after the newborn phase and lasts until the child reaches 12 months. During this time, the baby's organs develop rapidly but are not fully matured. The child grows quickly, doubling their birth weight within the first six months and tripling it by the end of the first year. Height increases by 50%. The nutritional needs are high, so it's important to ensure the baby receives breast milk, and when they reach six months, solid foods can be introduced.

Alongside physical development, mental and motor skills also grow quickly. From birth, the baby only has a few reflexes, but by the end of the breastfeeding period, the child can speak, walk, understand much more, and interact happily with those around them.