Her social media followers praised her for "keeping it real".
Model Christine McGuinness said Quek looked "stunning" while many others, including ex-England cricketer James Taylor and British sports presenter Emma Jones, replied with laughing emojis.
"That's just made me laugh so much and brought back similar memories," someone else commented.
"So refreshing that you've posted this on social media, the reality of motherhood that not many in your position show," another Instagram follower said.
"Ahhh a true picture of motherhood. It ain't all glam and roses. Thank you for posting a real pic," someone else added.
The former athlete turned TV star got pregnant just seven months after giving birth to her first child, Molly.
