birth mother

noun

1. the woman who gives birth to a child, regardless of whether she is the genetic mother or subsequently brings up the child

Example Sentences

But when the older of the two boys became a teenager, he told his adoptive mother he no longer wanted to write to his birth mother.

From BBC

Dee was advised it would be reassuring for Cassie to meet her birth mother face-to-face.

From BBC

Cassie still seemed to worry about her birth mother, and would try to call her on a toy telephone.

From BBC

After that, Cassie, who is now aged 30, says she didn’t want to see her birth mother again.

From BBC

Mainly, she took guest roles on dozens of shows, including playing the eccentric birth mother of Lisa Kudrow’s character, Phoebe, on NBC’s “Friends” in the late 1990s.

From Los Angeles Times