It may be normal for babies not to raise their heads at 45 days of age, but it may also be related to malnutrition, strabismus, cerebral palsy, and so on.
Babies can raise their head for a short period of time at 45 days of life, but it is unstable and the range of their head raising is small, which is usually a normal physiological phenomenon. However, preterm delivery and malnutrition can lead to developmental delay, resulting in babies being unable to raise their heads for 45 days.
There are also some pathologic factors that can cause babies to be unable to raise their heads normally. For example, in congenital cervical dystocia, the baby’s head and face are skewed to the healthy side, and there may be limited neck movement. As well, babies with cerebral palsy may also have backward motor development and central motor disorders, resulting in disorders of gross motor functions such as lifting the head, rolling over, sitting, and fine motor functions such as grasping and holding.
A 45-day-old baby who cannot hold his head up may also be related to lack of exercise, etc. If the baby is still unable to hold his head up stably by 4 months, it is recommended that he should go to the hospital for examination to clarify the cause and treatment.