Intrauterine G-CSF Infusion for Thin Endometrium

Thin endometrium is a condition in which the lining of the uterus is too thin during preparation for embryo transfer. This may reduce the chance of pregnancy and live birth in patients undergoing frozen-thawed embryo transfer.

This study will evaluate whether intrauterine infusion of granulocyte colony-stimulating factor, also called G-CSF, can improve pregnancy outcomes in patients with thin endometrium. Participants will be randomly assigned to one of two groups. The experimental group will receive mild endometrial stimulation followed by intrauterine infusion of G-CSF 300 μg. The control group will receive the same mild endometrial stimulation followed by intrauterine infusion of normal saline. Both groups will then continue standard endometrial preparation for frozen-thawed embryo transfer.

The main outcome of the study is the live birth rate. The study will also assess endometrial thickness, endometrial blood flow, clinical pregnancy rate, miscarriage rate, and safety outcomes, including adverse events, pregnancy complications, fetal malformations, and neonatal birth defects. Participants will be followed from enrollment through embryo transfer, pregnancy assessment, and delivery.

This is a single-center, prospective, randomized controlled trial conducted at Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School. The planned sample size is 620 participants.