A sac shaped like an upside down pear with a thick lining and muscles in the pelvic area where a fertilized egg or zygote comes to grow into a baby is called _______.

The uterus is a female reproductive organ located between the bladder and the rectum, in the pelvic area. The main purpose of the uterus is to nourish a foetus prior to birth. In menstruating females, the ovaries release eggs which travel via the fallopian tubes to the uterus.