what episode on glee does quinn have her baby
In an episode of season 1.
Quinn Fabray

Finn learns the truth about the baby's paternity from Rachel, and breaks up with Quinn. Puck again offers to support her, but she turns him down and tells him that she wants to handle the pregnancy by herself. She moves in with Puck's family, but after forming a friendship with fellow New Directions member Mercedes Jones (Amber Riley), Quinn lives with her family instead. She gives birth to a daughter, named Beth by Puck, who is adopted by Shelby Corcoran (Idina Menzel), coach of rival glee club Vocal Adrenaline and Rachel's biological mother.
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Quinn Fabray [SEP] Season 1
Her parents kick her out of their house, and she moves in with Finn and his mother. She begins to reconsider giving up the baby, and gives Puck a chance to prove himself, but he is not reliable so she returns to her plan of giving the baby to Terri. Quinn blackmails Sue into letting her rejoin the Cheerios, but ultimately decides against it, preferring to remain with the glee club, where she feels accepted. Finn learns the truth about the baby's paternity from Rachel, and breaks up with Quinn. Puck again offers to support her, but she turns him down and tells him that she wants to handle the pregnancy by herself.