For Rose of Sharon was pregnant and careful. Her hair, braided and wrapped around her head, made an ash-blond crown. Her round soft face, which had been voluptuous and inviting a few months ago, had already put on the barrier of pregnancy, the self-sufficient smile, the knowing perfection-look; and her plump body – full soft breasts and stomach, hard hips and buttocks that had swung so freely and provocatively as to invite slapping and stroking – her whole body had become demure and serious. Her whole thought and action were directed inward on the baby. She balanced on her toes now, for the baby’s sake. And the world was pregnant to her; she thought only in terms of reproduction and of motherhood.
– John Steinbeck
The Grapes of Wrath, Chapter 10. This describes Rose of Sharon and how pregnancy is affecting her. The passage emphasizes her maternal instincts and her strong desire to protect her unborn baby. There is also the suggestion that her young husband Connie is being deprived of sex by the baby, when Steinbeck writes about the "barrier of pregnancy."