The body of the newborn, nicknamed Baby Pearl, was found in woodland in Heywood, Greater Manchester, on April 4.
Greater Manchester Police have now revealed that the believe they little girl's mother may be a victim of rape or incest.
Detective Chief Inspector Lewis Hughes suggested the mother have been an abuse victim and was in "distress".
He told the Sunday Times: "Whoever left Pearl here was someone with no emotional attachment to that baby.
"There was not a scrap of clothing on her, she has been treated with no compassion.
"If it was the mother, she could be a rape victim, or a victim of abuse or incest - it may be a mother who has concealed the birth from others."
Mr Hughes said it was likely answers in the case lie in neighbourhoods surrounding the woods, and is appealing for anyone with any information to come forward.
Police named the tragic newborn Pearl after she was found in undergrowth by a dog walker on April 4 in Roch Valley Woods, Heywood, Greater Manchester.