PLATELET-RICH PLASMA INTRAUTERINE PERFUSION COMBINED WITH HYSTEROSCOPIC ENDOMETRIAL MECHANICAL STIMULATION: A NEW CHOICE FOR TREATMENT OF THIN ENDOMETRIUM.

Thin endometrium usually means abnormal endometrial receptive leading to implantation failure. Platelet-rich plasma (PRP) containing high concentrated platelets and proteins, such as various growth factors. It has been suggested that local endometrial mechanical stimulation (EMS) could recruit cytokines and growth factors to enhance endometrium and encourage embryo implantation. We aimed to investigate whether PRP intrauterine perfusion combined with hysteroscopic EMS affect the outcome of IVF in patients with thin endometrium. 32 patients undergoing In Vitro Fertilization-Embryo Transplantation (IVF-ET) in our center between 2016.07 to 2018.03, with thin endometrium (<7mm), were included in this study. All the patients had at least one fresh/frozen high-quality embryo transplantation failure history, and uterine cavity operation history. Hysteroscopy test showed uterine cavity was basically normal in morphology, and the endometritis was excluded. All patients were randomly divided into two groups: 17 patients in observation group undertook GnRH-a plus HRT, with hysteroscopic EMS and PRP intrauterine perfusion at the same time; the other 15 patients in control group were treated with GnRH-a plus HRT only. Estrogen replacement was performed after 28-30 days of GnRH-a treatment, and EMS was carried out on the same day (using mini-scissor to cut linearly along the longitudinal axis of the anterior and posterior wall of the uterus). 2-4 hours later, intrauterine perfusion with 2 ml of autologous platelet-rich plasma was carried out. The perfusion was taken every 2 days to the total of 3 perfusions. On 12-14 days of estrogen replacement, endometrial thickness and blood flow were determined by ultrasound to evaluate the time of point for using progesterone. Cleavage-stage embryos and blastocysts were transplanted on the 4 or 6 days after progesterone, respectively. Blood HCG was measured at 14 days after transplantation and ultrasound was employed at 34 days after transplantation. In terms of endometrial thickness in the endometrial transformation day, it was 6.15 ± 0.77mm in observation group, with no difference to those in last cycle (5.66 ± 0.64mm, p=0.0588), either no difference to the control group (6.04 ± 0.52mm, p=0.6508). While ultrasound showed in observation group patients, the endometrial blood flow was improved significantly after treatment of EMS and PRP. In the observation group, 9 out of 17 patients had clinical pregnancy, and the pregnancy rate was much high than that in the control group (2 out of 15) with statistical significance (p <0.05). Hysteroscopic EMS combined with PRP intrauterine perfusion is an effective method to improve implantation and clinical pregnancy of thin endometrium, via enhance endometrial receptivity by increasing the blood flow of the endometrium.