The ovaries are the sex gland of the female. In humans they are two in number, three to four centimeters in diameter, almond-shaped, and situated on either side of the pelvis in the folds of the broad ligament which supports the uterus. See figure below. With the onset of puberty, cyclic changes take place in the ovaries: after menopause they diminish in size and activity.
The function of the ovaries is the production of ova, and the sex hormones, progesterone and estrogens. The ovaries are glands of internal secretion, or endocrine glands. Two types of hormones are produced, the estrogenic group of which estradiol is the most important, and corpus luteum hormone or progesterone. These substances are concerned with the changes characteristic of menstruation, those following impregnation which are necessary for the development of the fertilizated ovum, and the changes in the ma??mary glands occurring during pregnancy. The ovary produces hormones that cause development of the female genital organs and secondary sex characteristics. The ovary is directly stimulated or inhibited by hormones from other endocrine glands, notably the pituitary.