baby

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Height and weight standard of baby

Age of baby	Baby boy's weight (kg)	Baby boy's height (cm)	Girl's weight (kg)	Girl's height (cm)
birth	2.9-3.8	48.2-52.8	2.7-3.6	47.7-52.0
January	3.6-5.0	52.1-57.0	3.4-4.5	51.2-55.8
February	4.3-6.0	55.5-60.7	4.0-5.4	54.4-59.2
March	5.0-6.9	58.5-63.7	4.7-6.2	57.1-59.5
April	5.7-7.6	61.0-66.4	5.3-6.9	59.4-64.5
May	6.3-8.2	63.2-68.6	5.8-7.5	61.5-66.7
June	6.9-8.8	65.1-70.5	6.3-8.1	63.3-68.6
August	7.8-9.8	68.3-73.6	7.2-9.1	66.4-71.8
October	8.6-10.6	71.0-76.3	7.9-9.9	69.0-74.5
December	9.1-11.3	73.4-78.8	8.5-10.6	71.5-77.1
May	9.8-12.0	76.6-82.3	9.1-11.3	74.8-80.7
18 months	10.3-12.7	79.4-85.4	9.7-12.0	77.9-84.0
21	10.8-13.3	81.9-88.4	10.2-12.6	80.6-87.0
2 years old	11.2-14.0	84.3-91.0	10.6-13.2	83.3-89.8
2.5 years old	12.1-15.3	88.9-95.8	11.7-14.7	87.9-94.7
3 years old	13.0-16.4	91.1-98.7	12.6-16.1	90.2-98.1
3.5 years old	13.9-17.6	95.0-103.1	13.5-17.2	94.0-101.8
4 years old	14.8-18.7	98.7-107.2	14.3-18.3	97.6-105.7
4.5 years old	15.7-19.9	102.1-111.0	15.0-19.4	100.9-109.3
5 years old	16.6-21.1	105.3-114.5	15.7-20.4	104.0-112.8
5.5 years old	17.4-22.3	108.4-117.8	16.5-21.6	106.9-116.2
6 years old	18.4-23.6	111.2-121.0	17.3-22.9	109.7-119.6
7 years old	20.2-26.5	116.6-126.8	19.1-26.0	115.1-126.2
8 years old	22.2-30.0	121.6-132.2	21.4-30.2	120.4-132.4
9 years old	24.3-34.0	126.5-137.8	24.1-35.3	125.7-138.7
10 years old	26.8-38.7	131.4-143.6	27.2-40.9	131.5-145.1

Basic law of weight gain index

·Normal term babies weigh about 2000-4000 grams at birth.

·In the first three months, the baby's weight increased by 180-200g per week, 150-180g per week at 4-6 months, 90-120g per week at 6-9 months, and 60-90g per week at 9-12 months.

·In terms of weight growth multiples, the baby's weight at 6 months is twice that at birth, about 3 times at the age of 1, about 4 times at the age of 2, and about 4.6 times at the age of 3.

·In the second year of life, the baby's weight increases by 2500-3000 grams on average.

·After the age of 2, the average annual growth rate is about 2000 grams until puberty.

Formula for calculating baby weight at different stages:

·Weight within 6 months=birth weight+month age × 600g

·7-12 months weight=birth weight+month age × 500g

·2-7 years old Weight=age × 2 ＋ 8000g

Tips

1. When measuring the baby's weight, it is necessary to discharge the urine and stool first and then empty the stomach

2. The weight of clothes and diapers should be subtracted

3. The weight should be measured once a month within one year old

4. Boys of the same age are heavier than girls

Basic rule of length growth index

·Length is the sum of the length of fingers, trunk and lower limbs. The proportion of the three is different in different stages of the baby.

·The average length of the baby at birth is about 50 cm.

·In the first year, the growth of body length was the fastest. The average growth was 2.5 cm per month from January to June, 1.5 cm per month from July to December, and 25 cm per month at the age of one year, about 1.5 times that at the time of birth.

·In the second year after birth, the growth rate of the baby's length began to slow down, increasing only 10-12 cm throughout the year.

·From the age of 2 until puberty, the baby's length increases by 6-7cm on average every year.

·The younger the age, the larger the proportion of head and upper body. The lower body grows faster than the upper body with age.

·The formula for calculating the length of 2-7-year-old babies=age × 5+75cm

Tips

1. Take off shoes, hats and socks when measuring your baby.

2. It is better to measure in the morning, so that more accurate values can be easily obtained.

The babies under 3.3 years old can be measured in the lying down position. When measuring, pay attention to straightening the knee joint and fixing the head with hands.

4. Boys of the same age are longer than girls.