When you have a baby, one of the first things people like to know — besides the baby's name — is their birth weight. Even before the baby's born, parents can start to worry about its growth and development in the womb, particularly if they've been told they're having a big baby. But does size really matter?
Babies come in all shapes and sizes
More than 9 out of 10 babies born at term (37 to 40 weeks) weigh between 2.5kg and 4.5kg.
If your baby weighs 4.5kg or more at birth, they are considered larger than normal. This is also known as 'fetal macrosomia' and large for gestational age (LGA). (If they weigh less than 2.5kg, they may be considered smaller than normal. )
How is a baby's size measured?
During routine antenatal check-ups, your doctor or midwife may estimate the growth and size of your baby by measuring the 'fundal height'. That is the measurement from your pubic bone to the top of your uterus.
An ultrasound can also give health professionals an idea of how big your baby is likely to be, but it's not very accurate.
Your doctor may also check the level of amniotic fluid. Excessive amniotic fluid, which surrounds the baby in the womb, can indicate the baby is larger than average, since larger babies can produce more urine.
However, there's no way of reliably measuring your baby's weight until after they are born. In many cases, women who are told they're going to have a large baby actually give birth to a baby within the normal range.
Why is my baby big?
A baby may be large at birth due to genetic factors, the mother's health or, in rare cases, a medical condition that causes the fetus to grow too quickly.
Several factors can contribute to large birth weight. For example:
the baby's parents' height and stature
if the baby is a boy (baby boys tend to be larger than baby girls)
having older siblings (the chance of fetal macrosomia increases with each pregnancy)
a previous pregnancy in which the baby was large
being overdue by more than 2 weeks
if the mother has diabetes during pregnancy
if the mother gains a lot of weight during pregnancy or is obese
if the mother is aged 30 or older
In some cases, larger-than-normal birth weight doesn't have a clear cause and can't be explained.
Giving birth to a large baby
Most large babies who weigh more than 4.5kg do not have a difficult birth. But there are still some risks associated with having a big baby.
Labour may take longer and be more likely to involve complications. There's an increased risk of having a forceps or vacuum-assisted delivery or a caesarean, and of birth injury to the mother or baby.
There is a link between fetal macrosomia and shoulder dystocia. Shoulder dystocia occurs during a vaginal birth when the baby's head has been born, but one of the shoulders becomes stuck behind the mother's pelvic bone. The baby's shoulders need to be released quickly so the baby's body can also be born, and they can start breathing.
Shoulder dystocia can happen during any birth. At least half of all babies who experience shoulder dystocia at birth weigh less than 4kg.
Large babies can be born via a normal, vaginal delivery — but it's best to give birth where you can access specialist medical services, just in case things don't go according to plan. Every pregnancy and birth is unique, so talk to your doctor or midwife about the best place for you to give birth.
After the birth of a large baby
Since many large babies are born to mothers with diabetes, some babies will need help regulating their blood sugar after they're born. Later in life, the risk of childhood obesity or being overweight may increase and the baby may develop other problems with their metabolism.
A larger than average baby may need help breathing following the birth, so they may be admitted to the neonatal intensive care unit (NICU) or special care nursery (SCN).
There is also an increased risk of jaundice (yellowing of the skin) among large babies.
Regardless of their size at birth, a baby's weight is always monitored closely after they are born to make sure they are healthy and growing properly. But their weight isn't the only thing that's important. How well they are feeding and the number of wet nappies and poos they produce daily can also indicate that your baby is doing well.
Can you avoid having a large baby?
Often there's nothing you can do to avoid having a large or small baby. But looking after yourself during pregnancy is important for all women. You should consider:
giving up smoking (if you currently smoke)
eating a balanced, healthy diet
maintaining your weight or, if overweight, losing weight before conception if possible
if you have diabetes, trying to manage it properly
avoiding alcohol and illegal drugs
Where to seek help
Always talk to your doctor, obstetrician or midwife first if you are concerned about your pregnancy, your own health or the health of your baby.
If you are worried about your baby's growth — or how fetal macrosomia might affect you as a mum — call Pregnancy, Birth and Baby on 1800 882 436 to speak to a maternal child health nurse.
Australian Institute of Health and Welfare (Australia's mothers and babies data visualisations), South Australian Perinatal Practice Guidelines (Fetal growth – accelerated), Department of Health (Clinical practice guidelines: Pregnancy care), health.vic (Gestational diabetes), The Royal Australian and New Zealand College of Obstetricians and Gynaecologists (Shoulder dystocia)
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: September 2020
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Guide to a healthy pregnancy
Pre-existing diabetes and pregnancy
Weight gain in pregnancy
Check-ups, tests and scans available during your pregnancy
Routine antenatal tests
Having a small baby
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The information is not a substitute for independent professional advice and should not be used as an alternative to professional health care. If you have a particular medical problem, please consult a healthcare professional.
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What Causes Big Babies? Busting Myths About Macrosomic Babies
Knowing the facts about what does (and doesn’t) cause larger newborns can provide comfort for parents-to-be.
Giving birth is never easy. And hearing from a doctor that your little nugget isn’t so little may cause expectant mothers added anxiety.
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Big babies can pose a challenge — but not as much as parents might fear.
“There are a lot of myths out there,” says David Marzano, M.D., an OB-GYN at University of Michigan Von Voigtlander Women’s Hospital.
The medical term for a large baby is macrosomia. A newborn receives this designation if he or she weighs 8 pounds, 13 ounces or larger at birth.
About 8 percent of the nation’s deliveries involve babies with macrosomia, according to the American College of Obstetricians and Gynecologists. But only 1 percent of newborns weigh 9 pounds, 9 ounces or more.
Marzano debunked some of the myths he hears from moms-to-be:
Myth: Baby size predictions are always right
Marzano uses three methods to predict a baby’s size but he readily admits they’re far from foolproof. The first is Leopold’s Maneuvers, which involves a doctor using both hands on the mother’s belly to feel the baby’s parts to determine size and location in the uterus.
“After a few years of experience, you get pretty good at predicting how big a baby is going to be with this method, but sometimes you’re surprised,” says Marzano, who delivered the largest baby of his career on the first day of his internship: a 12-pound, 6-ounce bundle of joy.
He also does his own research, asking the patient her birth history and using observational skills to see if both parents are unusually tall or heavy, often good predictors of a bigger baby.
The final tool is an ultrasound during the third trimester. But predictions using this technology can be off by as much as 20 percent, meaning a baby expected to weigh 10 pounds could be anywhere from 8 to 12 pounds. It is the least accurate tool late in this pregnancy stage, Marzano says.
Myth: Pregnant women who gain weight have bigger babies
Marzano has seen his share of patients who say they are bigger than their previous pregnancy or gained next to nothing compared to their last child.
SEE ALSO: Pregnant and Want Advice on Healthy Weight Gain? Google Isn’t Your Best Bet
This is not as important: “I’ve had these tiny women who’ve gained practically no weight and who exercise regularly give birth to large babies,” he says. “It makes me think, hmm, nature’s weird.”
Mothers with uncontrolled diabetes, both pre-existing and gestational — which first develops during pregnancy — run a higher risk of having babies with macrosomia.
Other influential factors include mothers with obesity, those with a prior history of macrosomia and babies who are overdue.
Moms with diabetes, whether gestational or a pre-existing sugar issue, must control their sugar with diet and exercise to avoid high sugar levels, Marzano explains.
The reason? Women with high sugar pass that glucose through the placenta. The baby’s pancreas senses it and makes more insulin to handle that higher load of sugar, a process that converts it into fat. The end result may be a larger baby.
Meanwhile, the higher sugar poses risks to the child after being born.
“That baby has to be monitored closely for several hours because it’s used to releasing more insulin because of mom’s sugar,” Marzano says. “When you clamp the cord, you take away the baby’s sugar supply and the baby’s blood sugar drops because there is more insulin present.”
Myth:A pregnant mother should eat for two
Should a mom-to-be double up at mealtime?
“That’s a myth,” Marzano says. “It probably came from a good place long ago when malnutrition was an issue, but that’s not a huge problem in the United States. ”
Marzano says that it wasn’t long ago when doctors advised every expectant woman to gain 30 to 40 pounds. Now, guidelines depend on mom’s starting weight. Average-weight mothers should gain 20 to 30 pounds; women who are overweight should shoot for 10 pounds. Women with obesity should stay the same weight, while morbidly obese women may lose weight, even while pregnant.
“Minimizing the weight gain is a better target than telling someone to lose weight, but letting them know that may prevent a 50-pound weight gain,” Marzano says.
Myth: Vegetarian diets prevent macrosomia
Giving up steak and seafood won’t affect a newborn’s weight.
“There is no evidence that a vegetarian has a lower risk of having a big baby than a person on a regular diet,” Marzano says.
While a healthy lifestyle can positively impact a growing baby, genetics can also play a large role, especially when it comes to conditions like gestational diabetes.
“Hormones that are involved with gestational diabetes are often not something mom can influence, and the higher blood sugar levels caused by those hormones can result in larger fetal growth,” Marzano says, adding that the condition can occur even in women who have no risk factors.
Myth: Large babies must be delivered via C-section
The risk of complications to both mom and baby increases with a newborn’s size, but that doesn’t mean a cesarean delivery is necessary, Marzano says. Both patient and doctor will discuss the risks and consult fellow medical experts.
If multiple signs indicate a baby will weigh more than 9 pounds, 9 ounces, the American College of Obstetricians and Gynecologists suggests a C-section.
If a patient chooses a traditional delivery, the patient is advised that she may receive an episiotomy (a surgical cut made at the opening of the vagina) or experience vaginal tears because special equipment like forceps may be used.
One of the most common problems during a vaginal delivery is shoulder dystocia, which occurs when a baby’s shoulder gets stuck under a mother’s pubic bone. It is considered a medical emergency because the baby is stuck in the birth canal and the umbilical cord is depressed, cutting off the oxygen supply.
To get the baby out, a doctor will have to perform several maneuvers to relieve the shoulder dystocia. This can include breaking the baby’s clavicle, if it hasn’t happened naturally in the birthing process. Permanent nerve injury or paralysis might occur, making the arm weak or unusable.
If that doesn’t help move the baby, fetal death may occur.
That said, scaring expectant moms is the last thing Marzano wants to do. Awareness, he knows, is the key to making an informed decision free of mistruths or myths.
Danila Bogatyr: the largest newborn of Tomsk celebrates 2 years
Danila Bogatyr: the largest newborn of Tomsk celebrates 2 years
Danila Bogatyr: the largest newborn of Tomsk celebrates 2 years - RIA Novosti, 01.03.2020
Danila Bogatyr: the largest newborn in Tomsk celebrates 2 years The hero at birth remained a hero even now: he catches up with his four-year-old brother in height and weight and does not let himself be offended.
Society, Tomsk, Tomsk region, Worldwide, Europe, Siberian Federal District, Russia
TOMSK, January 10 - RIA Novosti, Olga Trepova. Danila Shandrov, who became the largest newborn in the history of the Tomsk Regional Perinatal Center, turned two on Friday. The bogatyr at birth remained a bogatyr even now: he catches up with his four-year-old brother in height and weight and does not let himself be offended.
Read all the news of the region on RIA Novosti Tomsk >>
A giant baby delivery of a woman whose baby weighed 6.4 kilograms. The baby was born on Tuesday.
Tomichka Svetlana Shandrova on January 10, 2012 gave birth to a child weighing 6.4 kilograms and 61 centimeters tall, which is a rarity in medical practice. Usually, the weight of children born at term is from 3 to 3.5 kilograms. A child weighing from 3.5 to 5 kilograms is considered large, and more, in medical terminology, is already a "giant". According to statistics, the appearance of such children is very rare - one in 1.5 thousand.
When Danila was born in Tomsk two years ago, footage with a cheeky bundle spread around all the country's central TV channels. Now the child has changed: the hair has become lighter and the cheeks have become a little smaller. Of course, you cannot call him a giant, but he is still stronger and larger than his peers.
When I went to visit the Shandrovs, a plump, round-faced kid met me at the threshold and happily grabbed a chocolate egg with a surprise. A couple of minutes later, only one wrapper remained from the chocolate that the boy had ground on the run: a hero is a hero.
"When we were in the maternity hospital, many people went into the ward to look at Danya, and now he is just as strong: he has knocked down arms, strong shoulders, a big head, but everything is proportional. A month ago we went to the children's clinic and met there is a boy who is a year older than my son. I must say that Danilka is almost larger than him," says mother Svetlana.
Two-year-old Danila wears the shirts and shorts of his four-year-old brother Vlad, who, by the way, was also born weighing more than five kilos. In terms of height, Vlad is now taller than his younger brother, and their difference in weight is very small.
"Danilka weighs about 18 kilograms, and the eldest - 20. The only thing is that the eldest son is taller, although he himself is also a big boy. Danila's height is now 98 centimeters, I think that by the age of four he will surpass in size brother," the young woman explains.
10 October 2013, 10:03
Tomsk parents call their children by rare names - Severyan and YaroslavnaNewborns with rare names Severyan, Yaroslavna and Serafima were registered in the Tomsk region in 2013, the press service of the regional administration reported on Thursday.
She notices that the youngest son has a wide bone, from whom she inherited it is not clear: Svetlana is miniature, with her father, too, only height can be called heroic - under two meters, but he himself is thin. “Apparently, the genes of one of the ancestors,” says the interlocutor of the agency.
Danila does not go to kindergarten: like for many of his peers, there is no place yet. Svetlana is looking forward to this moment: it would be interesting for a sociable child to be in a team, besides, an extra penny that a mother could earn in the meantime would not hurt a family with two children.
Svetlana says that Danila is ahead of her peers not only in size, but also in development, according to her, he is more diligent and intelligent.
"The elder went to the garden, he didn't even want or didn't know how to put on socks, and Dana was still a year and a half old, he did everything by himself - dressed and ate. I sometimes try to feed him myself to do it faster and more accurately, but doesn’t give, he takes a spoon himself. He still doesn’t speak clearly, but already in sentences, for example: “Mom, I want yum-yum!” - the woman smiles.0003
Danila's appetite is also heroic, he does not have to be persuaded to eat for a long time. The most favorite dishes are chicken and meatballs.
"You buy a chicken breast, boil it, he just eats it without bread, without a side dish, and if he doesn't eat enough, he can even take it away from his older brother," my mother laughs.
January 3, 2014, 16:09
Eleven babies were born in the Tomsk region on New Year's Eve Eleven babies were born on New Year's Eve in the Tomsk region; the very first baby was born in maternity hospital No. 1 of Tomsk, an employee of the press service of the regional health department said.
The usual childish mischief
By the way, the Tomsk bogatyr also does not differ in embarrassment, he does not give himself offense, if Vlad inadvertently offends him, then "surrender" will surely "fly" from his younger brother.
"He "builds" me too. He can be mischievous, then I start scolding him, and he says: "Mom, be quiet!" When he grows up a little, I think that we will definitely take him to a circle to do karate or boxing, he it should work out," the interlocutor shares her plans for upbringing.
While we are talking, the sound of water and short remarks: "Koop-koop" came from the bathroom. It turns out that, taking advantage of the fact that mom is busy, the hero of the day made his way to the bathroom, climbed onto the chair, turned on the tap on his own and began to wash. The guests are coming soon!
The Shandrovs are observed at the polyclinic at the place of residence, everything is in order with the health of the hero. At birth, doctors said that Danka would equal his peers, like many large newborns, but it is already clear that this boy will definitely not be small.
The record is not broken
September 27, 2007, 15:58
The largest child of the millennium was born in Altai A girl weighing 7 kilograms 750 grams was born in the city of Aleysk, Altai Territory, Irina Molchanova, chief obstetrician-gynecologist of the region, told RIA Novosti on Wednesday.
After the birth of Danila, no one in the Tomsk region managed to break his record. According to the press service of the regional health department, eight children were born in the region with a weight of more than five kilograms over the past two years. The largest child was a girl weighing 5.7 kilograms, who was born in June 2013.
A baby weighing almost 9 kg was born in Indonesia - RBC
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The list of local champions included a resident of Indonesia, who recently gave birth to a child weighing 8.7 kilograms. According to British media, the baby became the heaviest newborn of all registered in the country.
An unusually large baby was born last Monday at the North Sumatra Provincial Public Hospital. His mother had a caesarean section.
The record-breaking baby was 62 cm tall, while the average Indonesian newborn is 40-45 cm. Sitangang.
The boy is doing well, according to hospital staff, although he initially needed supplemental oxygen due to breathing problems. At the same time, health workers note, the child has a very large appetite, and the mother has to feed him almost continuously. "This is an extraordinary child.