Which hormone acts directly on the uterine lining during the menstrual cycle?

Answer 1

Estrogen causes endometrial growth/proliferation. Post-ovulation, mainly progesterone acts to cause secretion, accumulation of glycogen and basically maintains the lining and prepares it for implantation. Removal of these hormones causes menstruation.

Answer 2

At ovulation a mature egg is released from the ovary, lutinizing hormone and follicle stimulating hormone cause the area from which the egg was released to become the corpus luteum, which produces progesterone - progesterone causes uterus lining to build-up.