Definition and categories of newborns

Infant refers to a baby from birth to 3 years old. Babies from birth to 28 days are called newborns. According to different indicators, newborns can be divided into different categories.

1. Classification according to gestational age

(1) Premature babies: babies born under 37 weeks of gestational age usually

(2) Full-term infants: newborn infants whose gestational age is over 37 weeks but are born under 42 weeks, with normal physiological indicators, which are also called normal infants.

(3) Expired babies: newborns born at 42 weeks of gestational age and above

2. Classification according to weight

(1) Normal weight infants: newborns whose birth weight is between 2500 and 3999 grams.

(2) Giant babies: newborns with a birth weight greater than or equal to 4000 grams.

(3) Low birth weight babies: newborns whose birth weight is less than 2500 grams.

(4) Very low birth weight babies: newborns weighing between 1000 and 1449 grams.

(5) Ultra-low birth weight infants: newborns weighing less than 1000 grams.

3. Classification according to the relationship between weight and gestational age

(1) Small for gestational age: newborns whose birth weight is below the 10th percentile of the same gestational age

(2) Suitable for gestational age babies: newborns whose birth weight is between the 10th to 90th percentiles of the same gestational age weight

(3) Children larger than gestational age: New birth weights above the 90th percentile of the weight of the same gestational age

4. Classification according to age after birth

(1) Early newborn: refers to newborns within 7 days after birth.

(2) Late neonates: refers to neonates from the second to four weeks after birth.

The newborn is born at full-term, with normal weight, suitable for gestational age, without abnormalities, and is a normal baby. Otherwise, there are various abnormalities, such as low birth weight infants, premature infants or diseases, etc., which are all high-risk infants.