The Walford businesswoman, played by Charlie Brooks, will learn that she is expecting her boyfriend Michael Moon's baby in a Christmas plot twist, according to the Daily Star Sunday.
It is thought that Janine is initially apprehensive over the idea of motherhood, but Michael (Steve John Shepherd) urges her to keep the baby - adamant that they should embrace their chance to become parents together.
An EastEnders insider told the newspaper: "Janine is completely shocked when she finds out she's pregnant. Her initial reaction is one of horror, especially as she still doesn't know whether she can trust Michael.
"He says he loves her and is excited about becoming a dad, but he always stirs up suspicion because of his track record. It's going to be a case of are these two dark souls genuinely in love, or does Michael in fact have an ulterior motive?"
Meanwhile, an EastEnders spokesperson said: "We do not comment on future storylines as we don't want to ruin it for our viewers."
Michael is already dad to baby Tommy Moon, but the child is being raised by mum Kat (Jessie Wallace) and stepfather Alfie (Shane Richie).
Today's report comes after EastEnders' executive producer Bryan Kirkwood recently told Inside Soap that Janine would make "a life-changing discovery" at Christmas.
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Watch Janine's EastEnders character trail below: