Now, the 43-year-old has revealed how, on one of those devastating occasions, her daughter had sensed her pregnancy had ended hours before she found out herself.
Speaking to The Sunday Telegraph's Stella magazine, the star recalled how her youngest daughter, Hero, walked into her bedroom one morning and told her: "Mummy, something's missing. I couldn't sleep last night. Something's gone."
The mother-of-three – who went on to give birth to two-year-old son Apollo in 2019 – explained that later that day she was distraught to find she had lost another baby.
Recalling how her daughters, Ava, 14, and Hero, now 10, supported her through this tough time, Klass added: "My girls lived this with me. They're so perceptive."
She described her multiple miscarriages as "just sheer terror, and blood and pain", noting that "then it’s paperwork, which is more pain".
The former pop star explained that after having a surgical procedure you then have to tick a box about what should happen to the "products of pregnancy".
She added: "The language is awful. And then you walk out with nothing. Everything you planned for is just gone. How do you prepare for something like that?
"I still wake my baby in the middle of the night to hug him – it will always affect me."
Klass is fronting an upcoming documentary, Myleene Klass: Miscarriage and Me, which will explore the toll of pregnancy loss on women.
It comes after she opened up last month about how the pain of miscarriage had impacted on her life.
Speaking to Psychologies magazine, she said: "I look at my body differently, because it's come through so much."
Klass revealed that, while pregnant with her son, she had been afraid to drink water for fear of needing the loo then seeing blood.
She said: "I know how ludicrous that sounds, but anyone who's been through miscarriage will know that stomach-tightening feeling when you pull down your knickers, thinking 'please, no blood'."
In January, she told You magazine how she had discovered she’d miscarried during a brief toilet break while hosting a live radio show.
Klass said: “I was on air. I went to the loo while the music was playing and there was blood everywhere. I didn't know what to do. I had one hour left of my show.”
She said she was able to continue presenting thanks to the support of friend Lauren Laverne, who fronts Radio 4’s Desert Island Discs.
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