As long as the head circumference is normal, it is not less than 46 cm when 1 year old and not less than 47 ~ 48 cm when 2 years old, so don't worry.
Under normal circumstances, when the baby is born, the posterior fontanel is very small or closed, which can only accommodate the size of a fingertip, and it will be closed at the latest 6 ~ 8 weeks after birth. At birth, the oblique diameter of the anterior fontanel is about 1.5 ~ 2.5 cm.
After birth, with the development of the head, the head circumference gradually increases, and the anterior fontanel will also increase. Six months after birth, with the gradual ossification of the skull, it gradually becomes smaller and generally closes at 1 year ~ 1 year.
Extended data:
Halogen door closing time
First of all, it is normal for a baby to close his fontanel when he is 1 year old to 1.5 years old. Some babies will close their fontanels later, and some babies will close their fontanels earlier, mainly depending on their physical fitness.
It is normal for babies to close the halogen door about two months earlier or later. If the fontanelle is not closed after two years old, you should go to the hospital for examination.
Secondly, as the baby grows up, the fontanel will gradually close, which can reflect the development and health of the baby's head. The closure of the baby's halogen door is affected by the disease. The premature or delayed closure of fontanel may be caused by this disease. If it is more than two years, we must understand the reasons.
Finally, if the infant's fontanel is closed prematurely, it is considered to be caused by brain dysplasia, and the head circumference should be measured regularly. Too small head circumference is microcephaly, which leads to the closure of fontanel, occipital protrusion and too wide forehead, which will also affect the health of babies.
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