Which part of the female reproductive system contains the major sex organ?

Ovaries are the primary sex organ of the female reproductive system. The ovaries are present in pairs that are of an almond shape in the human female reproductive system. The ovaries are responsible for producing female hormones such as oestrogens and progesterone, and eggs. These hormones play a crucial role in regulating the menstrual cycle, promoting the growth and development of reproductive organs, and maintaining pregnancy.