Mila first spoke about her plan to have a natural delivery when she announced her pregnancy on the Ellen DeGeneres show back in May.
"The hospital that I'm going to be laboring in does a midwife, you know, doula type of thing, and so I'm gonna do it as all natural as I possibly can unless that there's an emergency or something that should go wrong," she said.
"I'm crazy. I mean, I did this to myself - I might as well do it right."
Now a 'source' close to Mila and Ashton has told RadarOnline that Mila has been advised against ruling out pain relief due to her small stature.
"Mila was going to do an all-natural birth with no medications or sedatives, but she has been advised against this because she is such a small girl," said the source.
They also added: "Ashton will not accept this and refuses to see her in pain."
The 'source' also dropped a hint about Mila's due date.
"She is scheduled to be delivering in less than one month and she cannot wait," the mystery insider revealed, before adding that this baby is unlikely to be the couple's last.
"Mila wants to get pregnant again right after this child is born, and she is cleared to do so by her doctor. She loved being pregnant and wants all of her children to be close in age."
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