Which of these statements best describes the action of the hormone progesterone during pregnancy?

A) Progesterone produces the hormone human chorionic gonadotropin.
B) Duct formation in the breast is stimulated by progesterone.
C) Progesterone promotes sloughing of the endometrial wall.
D) Progesterone maintains the endometrium around the fetus.

Progesterone

A steroid hormone released by the ovaries, important for regulating menstruation and maintaining the early stages of pregnancy.

Endometrium

The mucous membrane lining the interior of the uterus, which thickens during the menstrual cycle in preparation for possible implantation of an embryo.

Human Chorionic Gonadotropin

A hormone produced during pregnancy by the placenta, commonly detected in pregnancy tests.