Sarah Stage gained just 18lbs in eight months of pregnancy

Expectant mom Sarah Stage is in her final trimester, and while she is nearing her eighth month of pregnancy, she has only gained 18lbs.

The 33-year-old Los Angeles-based model, who continues to baffle people online with her six-pack abs, took to Instagram Stories on Tuesday to share a clip of herself standing on a scale, writing: ‘Total weight gain so far: 18lbs.’

The 5’8″ Instagram star proudly revealed that she weighs 137lbs going into her 31st week week of pregnancy. 

Still trim: Sarah Stage revealed she has gained only 18lbs before sharing a sultry photo of herself 31-weeks pregnant 

‘Total weight gain so far’: The 33-year-old model took to Instagram Stories on Tuesday to share a clip of herself on a scale to show that she now weighs 137lbs 

Sarah, who also has a two-year-old son James Hunter, gained a total of 28lbs during her first pregnancy, and she seems to be on track to gaining the total 25 to 35lbs that is recommended for the average healthy pregnant woman.   

After sharing her pregnancy weight with her fans, Sarah returned to Instagram later that day to share a photo of herself showing off her incredible figure in a skimpy, white two-piece swimsuit.

The soon-to-be mother-of-two captioned the image: ‘#31weeks – baby is kicking like crazy!!’

Much like her first pregnancy, in which Sarah had a six-pack up until the day she gave birth, her Instagram feed is filled with comments from people who claim she harming her unborn child with her fitness regimen and trim physique. 

Online sensation: Sarah showed off her barely-there baby ump in a skimpy white swimsuit 

Online sensation: Sarah showed off her barely-there baby ump in a skimpy white swimsuit 

Throwback: Sarah first shot to fame in 2015 (pictured) after showing off a tiny baby bump while nine-months pregnant. She later revealed she had gained a total of 28lbs

Throwback: Sarah first shot to fame in 2015 (pictured) after showing off a tiny baby bump while nine-months pregnant. She later revealed she had gained a total of 28lbs

Sarah hit back at her critics last week by demonstrating the at-home workout routine that keeps her in tip-top shape while pregnant.  

The video she shared sees her performing squats, side-planks and various other exercises as her two-year-old son toddles around the room. 

In the caption, she revealed that she is nearly at the eight-month mark and wanted to take a moment to address the ‘Instagram medical experts’ who constantly post on her account.

‘While I find some of the comments hilarious, I choose to only listen to my OBGYN and of course I also listen to MY body. If something feels off, I don’t do it!’ she wrote. 

Making it work: Sarah showed off her flat stomach at nearly eight months pregnant in a new workout video she posted last week 

Making it work: Sarah showed off her flat stomach at nearly eight months pregnant in a new workout video she posted last week 

Getting it together: The clip sees her moving through a series of exercises to keep herself fit during her pregnancy

Getting it together: The clip sees her moving through a series of exercises to keep herself fit during her pregnancy

Getting it together: The clip sees her moving through a series of exercises to keep herself fit during her pregnancy

‘I always do what’s best for my growing baby and put him first! It’s a proven medical fact that continuing exercising while pregnant has many health benefits for you and baby.’

She finished her post by adding that she has ‘greatly reduced’ the intensity of her workouts and is only keeping fit because she values a healthy lifestyle. 

Of course, most of the attention on Sarah centers around the fact that she is barely showing any hint of a bump despite being so far along in her pregnancy. 

Earlier this month, she shared photos of herself modeling an orange bikini on Instagram, appearing to be a medical marvel with her completely unnoticeable bump.

Unbelievable: She continues to show essentially no hint of a bump despite being far along

Unbelievable: She continues to show essentially no hint of a bump despite being far along

Happy seven months: Sarah entered her third trimester of pregnancy earlier this month and shared this set of pictures to celebrate

Happy seven months: Sarah entered her third trimester of pregnancy earlier this month and shared this set of pictures to celebrate

All OK: Critics have said she is too thin and it can't be healthy, but she was equally slim when pregnant with her son James Hunter (pictured)

All OK: Critics have said she is too thin and it can’t be healthy, but she was equally slim when pregnant with her son James Hunter (pictured)

‘Hello #thirdtrimester!’ she wrote, captioning the two snaps. ‘These past #7months have flown by.’

She also revealed that she and her husband Kris plan for this baby to be their last, so she is ‘trying to stay in the moment and enjoy every second’ of this pregnancy.

During her sixth month of pregnancy, Sarah clapped back at her critics by sharing an ultrasound to show fans that her baby is healthy. 

‘Doctors appointment went great,’ she wrote. ‘Baby is weighing a little over 2lbs with a strong heartbeat and huge hands lol Thanks for all of the well wishes.’ 

Flaunting her curves: Sarah showed off her new jeans in July, explaining she can't fit into her other ones because she had gained 13lbs of pregnancy weight

Flaunting her curves: Sarah showed off her new jeans in July, explaining she can’t fit into her other ones because she had gained 13lbs of pregnancy weight

Take that: The model took aim at critics when she posted a picture from her recent ultrasound in July, pointing out that her baby is healthy

Take that: The model took aim at critics when she posted a picture from her recent ultrasound in July, pointing out that her baby is healthy

Four for a family: Sarah also revealed that she and her husband have decided this will be their last child

Four for a family: Sarah also revealed that she and her husband have decided this will be their last child

Babies rapidly grow during the sixth month of pregnancy, and by the end of the month, they should weigh about 2lbs and measure 12-inches from head to heel, according to WebMD.  

Sarah became an online sensation back in 2015 after images of her showing off her washboard abs while nine months pregnant went viral.

Although critics insisted her fit physique would negatively affect her baby’s health, her son James weighed over 8lbs at the time of his birth. 

The criticism during both pregnancies has not stopped her from doing what she does best — showing off her trim physique on Instagram.

‘The comments can get draining and part of me feels sorry for those negative people. But the only thing I can do is stay positive and only listen to my doctor who says that baby is measuring perfectly fine!’ she told Daily Mail Online in July.

Read more at DailyMail.co.uk