Genesis 16:3-6

16:3 So after Abram had lived in Canaan for ten years, Sarai, Abram’s wife, gave Hagar, her Egyptian servant, to her husband to be his wife. 16:4 He had sexual relations with Hagar, and she became pregnant. Once Hagar realized she was pregnant, she despised Sarai. 16:5 Then Sarai said to Abram, “You have brought this wrong on me! I allowed my servant to have sexual relations with you, but when she realized that she was pregnant, she despised me. May the Lord judge between you and me!”

16:6 Abram said to Sarai, “Since your servant is under your authority, do to her whatever you think best.” Then Sarai treated Hagar harshly, so she ran away from Sarai.

Genesis 16:15

16:15 So Hagar gave birth to Abram’s son, whom Abram named Ishmael.