Ruby Eden, 24, from Warrington, Cheshire, was originally told by doctors her newborn was likely to weigh around 9lbs, but he actually arrived weighing a hefty 11lbs 13oz with a head "as big as a melon".
When nurses went to weigh baby Teddie they joked that he literally tipped the scales, as he was so big he almost toppled them over.
Ruby and her husband Chris, 27, had been expecting their second child to be a bigger baby but say everyone was left shocked by their son's size when he was actually born.
The couple were forced to put Teddie straight into outfits for three-month-old babies as newborn clothes were already way too small.
"I was shocked when I saw Teddie for the first time," the mum-of-two explains.
"He was like a toddler. He was massive. My husband saw him and just said ‘he's a chunky boy’ as he was stunned.
“All the midwives gasped when they saw Teddie come out and I wished I had filmed my family members' expressions when they met him for the first time.
“Everyone was just so shocked and confused as to why Teddie was such a big baby."
Watch: Mum had baby so big she fitted into clothing for six-month-olds immediately
Ruby says that while she was pregnant with her son, her bump was actually smaller than when she was expecting her daughter.
“He [Teddie] must have been hiding the weight somehow," she explains.
“I took a newborn size hat in for Teddie to wear at the hospital and there was just no chance it was going to fit his head.
“It was the size of a small honeydew melon, and the nurse had to fetch me an extra-large baby one."
Ruby gave birth to Teddie in Warrington Hospital on 1 August, 2022 at 5:45pm, eight days after her due date.
After being told at her final scan her baby would be "slightly bigger" than normal she had prepared herself for another 9lb child like her daughter Delilah-Rose.
But, following an emergency C-Section the day after her 41-week scan, her sizeable bundle of joy weighed in at a whopping 11lbs 13oz.
“I was never expecting to have a child that was almost 12lbs," says Ruby.
“I’m glad I had a caesarean and not a natural birth."
Following her son's arrival Ruby has since shared her birthing story on TikTok and it has received 1.5 million views and more than 207k likes.
Teddie was born after his mother experienced a condition known as polyhydramnios, which occurs when there is too much amniotic fluid around the baby during pregnancy.
He then spent time in and out of hospital at six-weeks-old and lost a lot of weight due to issues with his liver.
"His liver couldn’t turn the calories he was getting from breastfeeding into glucose," his mum explains.
Thankfully now aged seven-months, his parents say their son is a healthy, happy baby who loves playing with his two-year-old sister.
“He is such a happy smiley baby and me and my husband are so proud of him," adds Ruby.
"But he's still considered an extremely large baby for his age."
While the family aren't expecting to have any more children, Ruby says she can't help but wonder how big her next baby would be if she were to have another.
"I would not be surprised if it was another big baby, maybe even bigger than Teddie," she says.
“There seems to be a pattern – they keep getting bigger each time.”
What is polyhydramnios?
Polyhydramnios is where there is too much amniotic fluid around the baby during pregnancy," according to the NHS.
While it is not usually a sign of anything serious, if you are diagnosed with the condition you'll probably have some extra check-ups during pregnancy and will usually be advised to give birth in hospital.
While most women with polyhydramnios will not have any significant problems during their pregnancy and will have a healthy baby, there is a slightly increased risk of pregnancy and birth complications, such as:
giving birth prematurely (before 37 weeks)
your waters breaking early
a problem with the position of the umbilical cord (prolapsed umbilical cord)
heavy bleeding after your baby is born because your womb has stretched
your baby having a health condition
Though there may not be any noticeable symptoms, signs of polyhydramnios include breathlessness, heartburn, constipation and swelling in the ankles and feet.
But these can be common problems for pregnant women and may not necessarily caused by polyhydramnios.
Talk to your midwife if you have these symptoms and you're worried.
Treatment for the condition can sometimes involve treating the underlying cause, if known, for example, changes to your diet or possibly medicine if you have diabetes.
Sometimes treatment may be recommended to reduce the amount of fluid, which can sometimes involve it being drained with a needle or being given medicine to help stop more fluid being produced.
Speak to your doctor or midwife if you're concerned or have any questions.
Additional reporting SWNS.