Genesis 18:10-12

Then one spoke up and said, “I will return about this time next year, when your wife Sarah will certainly have a son.” Sarah overheard it, for she was at the tent door not far behind him. Now, both Abraham and Sarah were already very old, and Sarah was past the age of childbearing. Sarah laughed to herself with disbelief, saying, “A woman my age—have a baby? After I’m worn out will I now enjoy marital bliss and conceive—and with my aged husband?”