Sarai, Abram's wife, hadn't yet produced a child.
Sarai said to Abram, "God has not seen fit to let me have a child. Sleep with my maid. Maybe I can get a family from her." Abram agreed to do what Sarai said.
So Sarai, Abram's wife, took her Egyptian maid Hagar and gave her to her husband Abram as a wife. Abram had been living ten years in Canaan when this took place.
He slept with Hagar and she got pregnant. When she learned she was pregnant, she looked down on her mistress.
Sarai told Abram, "It's all your fault that I'm suffering this abuse. I put my maid in bed with you and the minute she knows she's pregnant, she treats me like I'm nothing. May God decide which of us is right."
"You decide," said Abram. "Your maid is your business." Sarai was abusive to Hagar and she ran away.