How big will my baby be at birth calculator
Birth Weight Percentile Calculator
Created by Dominika Śmiałek, MD, PhD candidate
Reviewed by Dominik Czernia, PhD candidate and Jack Bowater
Based on research by
Villar J, Cheikh Ismail L, Victora CG, Ohuma EO, Bertino E, Altman DG, Lambert A, Papageorghiou AT, Carvalho M, Jaffer YA, Gravett MG, Purwar M, Frederick IO, Noble AJ, Pang R, Barros FC, Chumlea C, Bhutta ZA, Kennedy SH “International Fetal and Newborn Growth Consortium for the 21st Century (INTERGROWTH-21st). International standards for newborn weight, length, and head circumference by gestational age and sex: the Newborn Cross-Sectional Study of the INTERGROWTH-21st Project“ Lancet (September 2014)See 1 more source
Hadlock FP, Harrist RB, Martinez-Poyer J. “In utero analysis of fetal growth: a sonographic weight standard.“ Radiology (October 1991)
Last updated: Jun 27, 2022
Table of contents:- Average baby weight by a week of delivery ⏳
- Average weight of newborn baby 👶
- Abnormal newborn weight causes
- Birth weight percentile calculator ⚖️
- Newborn weight percentile calculator in practice
- FAQ
Are you looking for a tool to estimate your baby's weight at birth, regardless of their gestational age? Use this birth weight percentile calculator to find out where among their peers your child places. It not only shows the average weight of a newborn baby, but this calculator also adjusts their weight according to the week of pregnancy in which the baby was delivered.
In the article below, you can find some information on the average newborn weight, the average newborn weight classification, and an explanation of how to use this birth weight percentile calculator.
Average baby weight by a week of delivery ⏳
The weight of a baby at birth differs depending on their age when they are delivered, which causes their adjusted age to differ. The age from which a baby can survive outside the uterus is 24 weeks old.
On the other side are babies that are 41 weeks old. If they're not born before that time, induction of delivery is necessary to prevent complications, such as meconium aspiration.
Because of such a wide range of possible pregnancy length, the average weight of a newborn baby may also vary.
Average weight of newborn baby 👶
The average birth weight for newborns born full-term is between 5.
5 lb (2.5 kg) and 8.8 lb (4 kg).
What is the classification?
- Extremely low birth weight (ELBW) is a term used for infants who weigh less than 1,000 g at birth (2.2 lb).
- Very low birth weight (VLBW) describes babies born weighing less than 1,500 grams (3.3 lb).
- Low birth weight (LBW) is when a baby's weight is less than 2,500 g (5.5 lb), no matter the gestational age.
- Normal weight (NBW) is if the baby weight is between 2,500 and 4,000 g (5.5 - 8.8 lb)
- High birth weight (HBW) is for babies born weighing more than 4 kg (8.8 lb).
There are more babies every year born at both extremes - with HBW and LBW. What are the reasons? For HBW mostly the increasing quality of life and the number of metabolic and chronic diseases among mothers, such as diabetes. For babies with a low birth weight, developments in medicine and healthcare mean that they are now more likely to survive in utero.
Also, children from multiple pregnancies, such as twins, triplets, etc. tend to be delivered preterm and with a weight lower than the average.
Infants with ELBW, VLBW, or LBW are at a high risk of complications such as hypothermia, hypoglycemia, perinatal asphyxia, respiratory distress, anemia, impaired nutrition 🍼, infection, neurological trouble, and hearing problems.
Abnormal newborn weight causes
A preterm birth (before week 38) or slow prenatal growth may cause low birth weight. There are however other causes, such as genetic factors, maternal health issues, or problems with the placenta. 👩
A weight over 4 kg is usually due to a big baby, or the mother gaining more weight than average during the whole pregnancy. Again, the cause may be genetic or due to maternal issues (such as diabetes).
Birth weight percentile calculator ⚖️
To estimate the newborn weight percentile, you only need to know two values. The first one is the gestational age of the baby at birth, given in weeks.
The second one is their weight.
Once you put in the data, the result - the exact percentile - will appear. The result is estimated based on the fetal weight equation proposed by Hadlock et al.
Below the calculator you can see a birth weight percentile chart with percentiles marked in different colors. The 50th percentile is the average weight of a newborn baby. It means that 50% of babies born at that age weigh more than this value and 50% weigh less. Your result is a dark dot, found somewhere between the percentile lines. The X values are the gestational age at which the baby may be born (between 24 and 41 weeks), and the Y values are weight. The color lines are percentile lines to help you read where your result is.
Newborn weight percentile calculator in practice
Let's work on an example of a newborn weight percentile calculation. Lucy, born yesterday, was born in the 35th week of pregnancy, a bit too early.
The neonatologist wants to calculate the percentile she's in according to her weight. The physician knows that preterm birth is a cause of low weight relative to children born on their due date. She uses this birth weight percentile calculator to estimate how Lucy's weight compares with the other children born at week 35.
She weighs 2350 g (5.181 lb). According to our calculator, that puts her between the 25th and 50th percentile (to be precise, the 43.42th percentile). This means that a little more than 50% of the children born at 35 week of pregnancy weight more, while a little more than 40% of infants have a lower weight than her. She has a perfectly normal body mass!
FAQ
How do we call babies with birth weight lower than the average?
Such a baby can be classified as either:
- Low birth weight (LBW): 1500–2500 grams;
- Very low birth weight (VLBW): 1000–1500 grams;
- Extremely low birth weight (ELBW): 750–1000 grams; or
- Incredibly low birth weight (ILBW) (which is very rare): 500–750 grams.
What do we need to know to estimate the newborn weight percentile?
The tables for birth weight percentiles require these data points:
- Gestational age at the time of birth;
- Gender of a baby; and
- Current weight of a baby.
How to estimate the birth weight percentile?
We estimate the newborn percentile using the birth weight percentile curves or tables. Such graphs require us to know the gestational age, gender and weight of a baby. All these points of information allow us to find the specific place on a curve and compare your baby's growth to that of the general population.
Why is my baby losing weight after birth?
It is entirely normal for a baby to lose around 7–10% of their weight soon after birth. The weight loss is primarily due to the excretion of their first urine and stool. The baby will regain the lost weight during the next 2 weeks.
Dominika Śmiałek, MD, PhD candidate
Gestational age
Weight
Percentile
Check out 7 similar percentile calculators 👶
Baby percentileChild BMI percentileChild height percentile… 4 more
You Can Predict Your Newborn's Weight
Equation Just as Good as Ultrasound, Easier to Use
Written by WebMD Editorial Contributors
Sept. 26, 2002 - A new baby's gender, name, time of birth, and birth weight are nice information for a birth announcement, but birth weight is especially important for an obstetrician. A large size at delivery has long been associated with an increased risk of injuries to a newborn and its mom. So the better a doctor can predict birth weight, the easier the delivery may be.
Most of the time, birth weight is predicted with ultrasound. Now researchers say a mathematic equation is just as good a predictor and can predict birth weight earlier than ultrasound for some newborns.
Duke University Medical Center doctors tested the accuracy of an equation that calculated birth weight based on stage of pregnancy, mother's height and weight, third-trimester weight gain rate, the number of other children, and fetal sex.
When they used it for 244 women who gave birth to single babies, the equationaccurately predicted birth weight within an average of 8% of actual birth weight. For 87% of the births, weight was predicted within 15% of the actual weight. Ultrasound is estimated to predict within 8-15% of true birth weight.
It was also easier for doctors to identify babies who might be bigger than 8.8 pounds, a weight at which the risk of delivery problems begin to increase.
The researchers say the equation is easier to use and more efficient than ultrasound. "The equation requires no additional testing, trained staffing, or equipment, and the information needed can be gleaned from the mother's current medical records," says Gerard Nahum, MD, of Duke's department of obstetrics and gynecology. "It can be computed by most doctors in about two to three minutes," he says in a news release.
The mathematical formula does have its limitations.
The study looked at only white nonsmokers who didn't have high blood pressure or diabetes and who gave birth to a single baby after 37-42 weeks of pregnancy. Researchers say others were excluded because differences in racial groups are linked to differences in birth weight. And high blood pressure and premature birth are linked to low birth weight while diabetes is linked to high birth weight.
A key to the equation's accuracy is knowing exactly -- or nearly exactly -- how long a woman has been pregnant, which is calculated using the last day of the her last period or by analyzing an early ultrasound.
Nahum says the equation also can be used early in the third trimester, since most women see their doctors every two weeks by that time. Third-trimester weight gain can be calculated once the woman has been weighed twice during the third trimester.
For those of you who have a thing for math, here's the equation:
Birth weight (g) = gestational age (days) x (9.
38 + 0.264 x fetal sex + 0.000233 x maternal height [cm] x maternal weight at 26.0 weeks [kg] + 4.62 x 3rd-trimester maternal weight gain rate [kg/d]] x [number of previous births + 1]).
Pointers for performing the calculations:
- Perform all multiplications before the additions.
- Gestational age is the stage of your pregnancy in days, or days since the onset of your last normal menstrual period plus 14.
- For fetal sex, use 1 for a boy, -1 for a girl, or 0 if sex is unknown.
- For mother's height, inches multiplied by 2.54 gives you centimeters.
- For the mother's weight, pounds divided by 2.2 gives you kilograms.
- For the baby's birth weight, take the number from your calculation and divide by 453 to get your baby's estimated weight in pounds.
If you don't have a thing for math, you might want to show this to your obstetrician. -->
How to find out how tall a child will be when he grows up: calculator and growth rates
Health
- Photo
- Photo Alto / Legion
pediatrician
In the first year of life, children literally grow by leaps and bounds hours and grow 25 centimeters by their first birthday.
Growth hormone is produced in the endocrine gland, which is located in the brain. This happens when the baby is sleeping, which is why healthy and restful sleep is so important.
“From one to three years old, a child on average gains 10 centimeters a year,” says pediatrician Marina Fedyushina. - From three to six years, the growth rate decreases: the mark on the stadiometer increases by about 4-5 centimeters. Until the age of 10, there is a slight slowdown, and already from the age of 11 (for girls) and from 13 years (for boys) there is a sharp jump in growth rates. After 40 years, we begin to decrease a little. This is due to fluid loss from the intervertebral discs.”
Place of birth matters
Obviously, growth is due to heredity. It is the genes that determine whether your son will be teased by Gulliver, and your daughter by Thumbelina. Not so simple.
“In 2014, American scientists conducted a large-scale study on the influence of genes on human growth,” says Doctor of Biology Antonina Volkova .
- The project was carried out by specialists from 300 institutes, and the number of participants reached 250 thousand people. The experiment proved that human growth is influenced by various gene variations, and there are about 300 hundreds of them. It is important what were your ancestors (not just parents), from whom you got a certain appearance.
The scientists also found out that the northerners are much taller than the inhabitants of the southern regions. For the first time, the German biologist Karl Bergman told the world about this, he said that a hot climate contributes to a slowdown in growth processes.
- Photo
- Photo Alto/Legion
Growth Formulas
Doctors have come up with a few simple formulas that can be used to predict where in the ranks your child will stand in physical education classes.
1. The most common formula
Boy height (cm) = (Mother's height + Father's height) * 0.
54 - 4.5 (cm)
Example: (165 + 183) * 0.54 - 4.5 (cm) = 183 .4 (cm)
Girl's height = (mother's height + father's height) * 0.51 - 7.5 (cm)
Example: (159 + 173) * 0.51 - 7.5 (cm) = 161.8 (cm)
2. Dr. John Hawker's formula
An employee of one of the largest private medical centers in the world, the Mayo Clinic, proposed the following calculations:
The boy's height is = (Father's height + Mother's height): 2 + 6.4
Example: (183 + 165): 2 + 6.4 (cm) = 180.4 (cm)
Girl's height = (Father's height + Mother's height): 2 - 6.4
Example: (173 + 159): 2 - 6.4 (cm) = 159.6 (cm)
Boy's height = (Father's height + Mother's height * 1.08): 2
Example: (183 + 165 * 1.08): 2 = 180.6 (cm)
Girl's height father * 0.923 + mother's height): 2
Example: (173* 0.923 + 159): 2 = 159.3
- Photo
- Image Source/Legion
reasons:
-
Emotional overloads,
-
Irrected nutrition,
-
Chronic diseases,
-
Climatic and geographical conditions,
-
Chromosomal disorders (for example, Daun's disease), 9,0002,
003
-
malformations of bones.
4. The Smirnov-Gorbunov formula
The authors of the sensational article "Short stature in childhood" Professor Vladimir Smirnov and endocrinologist Gleb Gorbunov also wondered what height a child would have in adulthood. This formula allows an error of as much as 8 cm:
Boy's height = (Father's height + Mother's height + 12.5): 2 ±8
Example: (183 + 165 + 12.5): 2 ±8 = 188.25 (cm) or 172.25 (cm)
Girl's height = (father's height + mother's height - 12.5): 2 ±8
Example: (173 + 159 - 12.5): 2 ±8 = 167.75 (cm) or 151.75 (cm) )
5. The formula for the growth of a child per year
According to the World Health Organization, the normal height of a one-year-old boy is considered to be from 71 to 80.5 cm, for girls - from 68.9 to 79.2 cm. If you want to know what will be your baby by the age of 20, it is necessary to add 100 cm (for a boy) and 95 (for a girl) to the height that the baby reached at 12 months.
Based on this formula, boys can only grow to 180.
5 cm and girls to 174.2. How then to be with Ivan Urgant, who has reached a height of 195 cm?
Professional sports can also change appearance. If you don’t want a modeling career for your child, then feel free to give it to gymnastics: a serious load on the joints and bones, spinal injuries contribute to problems with the development of the skeleton, children grow poorly. Although the famous gymnast Laysan Utyasheva has grown to 167 centimeters, this is quite a normal height for a girl. But swimming, football, hockey, tennis, volleyball will allow you to become taller, faster and stronger.
Pediatricians themselves do not particularly trust these methods of calculating height.
“There will always be errors,” continues Marina Fedyushina. - The growth rate, in addition to heredity, is influenced by various factors. First of all, this, of course, is the state of the endocrine glands. Do not discount nutrition and lifestyle. Lack of vitamins, smoking and alcohol slow down the growth of the child”
Yulia Evteeva
0001
Ekaterina Miroshkina
economist
Author profile
The Ministry of Labor has published a draft resolution with the coefficient of indexation of maternity capital according to actual inflation: in 2022, the size of this type of state support will increase by 8.
4%. The maximum amount of the increase will be 53,712.27 R. So far, there is no government decree, but there is no doubt that everything will be so.
Previously, mother's capital was indexed to planned inflation: in 2020 - by 3%, in 2021 - by 3.7%.
- Source:
- Ministry of Labor
What will be the capital in 2022
639,431.83 R → 693,144.1 R;
155,550 R → 168,616.2 R.
The amount is determined by the year the state support was ordered, and not by the date the certificate was issued. Details are further in the article.
Maternity capital for the first child
For the first child, maternity capital is assigned only at birth starting from 2020.
If you dispose of state support before February 1, the amount will remain the same - 483,881.83 R. When using mother capital from February 1, 2022, it will increase to R 524,527.9 - by R 40,646.07.
Capital for the second child
The amount depends on the year the children were born.
Change in maternity capital for the second child
| When the children were born | Maternity capital in 2021 | Maternity capital in 2022 |
|---|---|---|
| The first and second - up to 2020 | 483 881.83 r for the second | 524 527.9 r for the second |
| The first - the second - in 2020 or later | 639 431, 83 r on the second | 693 144.1 r on the second |
| The first and second - from 2020 | 483 881.83 r for the first | 524 527.9 r for the first, 168 616 ,2 R on the second |
The first and second child
were born until 2020
Matkapital in 2021
483 881.83 r for the second
Matkapaled in 2022
524 527.9 r for the second
The first child was born up to 2020 ,
The second - in 2020 or later
Matkapital in 2021
639 431.
83 r for the second
Matkapital in 2022
693 144.1 r for the second
The first and second child
were born from 2020
Matkapital in 2021
483 881.83 r for the first, 155 550 r for the second
Matkapal in 2022
524 527.9 r for the first, 168 616.2 r for the second
If the mother capital was previously assigned for the first child, but the entire amount has already been used, only the surcharge for the second child is indexed. That is, at the birth of another child in the family, you can receive 168,616.2 rubles.
Capital for the third or subsequent children
The amount of state support depends not only on the date of birth of the child, but also on the rights to maternity capital until 2020.
Change of uterus for the third child
| When children | were born in 2021 | Matkapal in 2022 |
|---|---|---|
| Two - until 2020 | 9021.524,527.9 R for the third | |
| Two — until 2007, third — from 2020 | 639 431.83 r on the third | 693 144.1 r for third |
| Two - to 2020, from 2020 | 483 881.83 on the second | 9020 r for second 9
Two - until 2007, the third - up to 2020
Matkapital in 2021
483 881.83 on the third
Matkapal in 2022
524 527.9 r for the third
two - until 2007 - until 2007 - until 2007 , third — since 2020
Matkapital in 2021
639 431.83 r for the third
Matkapital in 2022
693 144.1 r for the third
two, the third - from 2020
Matkapyal in 2021
483 881.83 for the second child
Mother capital in 2022
524 527.9 R for the second child
If the mother capital was assigned to the second child until 2020, and then the third was born, there are no additional payments. Only the amount that the family did not use can be indexed.
Rights of parents with maternity capital
Maternity capital for twins
When twins are born, the amount of maternity capital depends on whether there are other children in the family and what year they were born.
If these are the first children for the mother and they were born before 2020, the capital is assigned to the second child, but according to the old rules. From February 1, 524,527.9 rubles can be used. Including the increase, this is a total of 693 144.1 Р. 1 R;
If the family already had two children, the mother capital is not required for the birth of twins. He has already been appointed before. Only the unused amount can be indexed.
Exception for cases where two children were born before 2007. Then the mother capital will be assigned to the third child - the first of the twins - in the amount of 693,144.1 rubles. In 2020, it is assigned automatically - according to data from the registry office. An electronic certificate arrives in the mother's personal account at public services within a few days after the birth is registered. You don't need to do anything for this.
If the child was born earlier or the certificate has not arrived, you can apply: at public services, through the PFR website or in person. It takes 5 working days for processing.
To spend the mother's capital, you need to submit one more application - for an order. When paying off a mortgage, this can be done at the bank. In other cases, at public services or in person, including through the MFC. The decision will be made within 10 working days after the submission of documents, the transfer of money - within 5 days after the decision.
