This real-world study aimed to assess the clinical efficacy and safety of intravenous immunoglobulin (IVIG) in treating unexplained recurrent pregnancy loss (uRPL) patients. A total of 238 patients with uRPL were enrolled in this retrospective study. According to the treatment, patients were assigned into treatment group (n=184, receiving IVIG+low molecular weight heparin [LMWH]) and control group (n=54, only LMWH). The primary outcome was the live birth rates (LBR) after 24 weeks of gestation. In addition, we performed subgroup analyses to assess the LBR in uRPL patients with age (≥30 years or <30 years), body mass index (BMI, 18-24 kg/m