Which hormonal pair would maintain the endometrium and make it receptive for implantation of embryo?

Explanation

The hormonal pair that plays a crucial role in maintaining the endometrium (the lining of the uterus) and making it receptive for the implantation of an embryo consists of progesterone and estrogen. During the menstrual cycle, estrogen is primarily produced by the developing ovarian follicles. In the early phase of the menstrual cycle (follicular phase), rising estrogen levels stimulate the growth and proliferation of the endometrial tissue. Estrogen also promotes the development of blood vessels and glands in the endometrium. Following ovulation, the ruptured follicle transforms into a structure called the corpus luteum, which secretes progesterone. Progesterone acts in conjunction with estrogen to further prepare the endometrium for possible implantation. It causes the glands in the endometrium to become more secretory, increases the thickness of the uterine lining, and helps create a receptive environment for a potential embryo.