Is Sakura, Sarada's biological mother? In the new manga mini-series, Sarada figures out the girl in glasses with Sasuke to whom Sarada seems to look like (the glasses, the face). I was wondering if maybe Sakura isn't her biological mother and that Sarada is a child of Sasuke and the other girl in picture.
Everything in this answer takes place after Shippuden ends and should be considered a spoiler.



In Naruto Gaiden: The Seventh Hokage and the Scarlet Spring Sarada is unsure of who her real mother is after finding a picture of Sasuke with Karin. Since Sarada had never meet her father she follows Naruto to meet Sasuke and find out the truth about her biological mother. When she meets Sasuke he says that its nothing to do with her and leaves it at that.



Later in Orochimaru's hideout Sarada ask Suigetsu about Karin to see if she was there in the hideout or if he knew who her real mother is. Suigetsu did know the answer but remembered that Karin had an umbilical cord in her desk. Suigetsu thought it was from Karin's birth. He then did a mouth swab on Sarada and preformed a DNA test. The test was a positive match. This leave Sarada to think that Karin is he biological mother.



It is later revealed that Karin could not be Sarada's mother because she was the one who delivered her. Karin tells Suigetsui that the umbilical cord he tested was Sakura's and that she was Saradas biological mother.