Elena Gilbert in the books does not have children,as in the series.So,maybe you thought of Nina Dobrev who plays Elena in the series - no she hasn't got any children.
The uterus is part of a woman's reproductive system that is located in the pelvis between the bladder and the rectum. The uterus is the hollow, pear-shaped organ where a baby grows. The narrow, lower portion of the uterus is called the cervix. The broad, middle part of the uterus is called the body, or the corpus. The dome-shaped top of the uterus is called the fundus. The fallopian tubes extend from either side of the top of the uterus to the ovaries.
The uterus is a female reproductive organ located between the bladder and the rectum, in the pelvic area. The uterus has three layers: the inner lining (endometrium); the middle muscular layer (myometrium); and the outer layer (perimetrium). The uterus is connected to the fallopian tubes, the cervix, and (via the cervix) the vagina. The main purpose of the uterus is to nourish a fetus prior to birth. In menstruating females, the ovaries release eggs that travel via the fallopian tubes to the uterus. If fertilized, the eggs will bind themselves to the wall of the uterus and the fetus will develop.