ANATOMY

Detailed explanation-1: -The hormone responsible for these changes is progesterone, which is manufactured by the corpus luteum. Under the influence of progesterone, the uterus begins to create a highly vascularized bed for a fertilized egg.

Detailed explanation-2: -Progesterone is one of the main female reproductive hormones, responsible for regulating the menstrual cycle and supporting pregnancy. Its levels in the blood vary throughout each menstrual cycle, and drop when a woman goes through menopause, and her periods stop.

Detailed explanation-3: -How is progesterone controlled? The formation of the corpus luteum (which produces the majority of progesterone) is triggered by a surge in luteinising hormone production by the anterior pituitary gland.

Detailed explanation-4: -During the second phase of the menstrual cycle, the effects of progesterone result in the proliferation of the endothelial lining in the endometrium, resulting in a thickened endometrial wall. The result is an increased thickness and surface area of the endometrium in which implantation can occur.