The endometrium is the soil that nurtures life and is a key component of female reproductive health. When the endometrium is severely damaged, the basal layer of the uterus is damaged, and the proliferation ability of the cells in the basal layer is impaired. The most direct manifestation is the thinning of the endometrium. At the same time, the severely damaged endometrium may undergo pathological repair during the repair process, resulting in varying degrees of fibrosis. In severe cases, it may even lead to uterine cavity adhesions and uterine cavity occlusion. Damage to the endometrium can easily lead to reduced menstruation, amenorrhea, recurrent miscarriage, and infertility, which may manifest as recurrent implantation failure during in vitro fertilization-embryo transfer. Therefore, the repair of endometrium damage is a difficult issue that needs to be solved in the reproductive field. Platelet-rich plasma (PRP) is a platelet concentrate obtained by drawing peripheral blood and centrifuging it. The main components are platelets, fibrin, and white blood cells. At the same time, platelets release a variety of growth factors after activation, which can play a role in tissue regeneration. The PRP used for clinical treatment is derived from one's own peripheral blood, has no risk of viral infection and autoimmunity, and has no ethical controversy. In addition, PRP has the advantages of simple, fast, and economical preparation. Therefore, PRP is widely used in many medical disciplines such as orthopedics, dermatology, dentistry, and gynecology.

Growth factors secreted by platelets are the main components of PRP and play a very important role in tissue regeneration, vascular remodeling, angiogenesis, inflammatory response, and other processes. PRP can promote the proliferation of endometrial cells and promote angiogenesis by inducing the migration, proliferation, and differentiation of vascular endothelial cells. Studies have shown that PRP promotes the recovery of endometrial structure and inhibits fibrosis after uterine horn injury. The inflammatory chemokines and high concentrations of leukocytes secreted by platelets in PRP after activation play an important role in inhibiting the body's inflammatory response and controlling infection. 

Clinical application of PRP in endometrial injury: Thin endometrium, intrauterine adhesions, recurrent implantation failure, chronic endometritis. 

The PRP currently used in these clinical studies differs in dosage, administration time, administration frequency, and administration method. Most studies have used direct infusion of PRP into the uterine cavity. This method of infusion makes PRP float on the surface of the endometrium, which makes PRP easily affected by uterine contractility and gravity. PRP flows out of the uterine cavity soon after infusion. There are shortcomings such as short drug action time and low dosage. In addition, there are studies on infusing PRP immediately after surgery, so that the residual fluid in the uterus after surgery will dilute PRP and reduce the efficacy of PRP. Some scholars have proposed a method of injecting PRP into the sub-endometrial layer under hysteroscopy to achieve the effect of retaining sufficient PRP in the uterine cavity for a long time and continuing to promote endometrial growth.

PRP is rich in a variety of growth factors and cytokines and plays a role in promoting endometrial cell proliferation, promoting angiogenesis, inhibiting fibrosis, and anti-inflammatory effects in the repair of endometrial damage. Judging from the current research, no adverse events have been found in the application of PRP in the repair of endometrial damage. PRP can promote endometrial repair to a certain extent and improve pregnancy outcomes.