Objective To investigate the expression of serum progesterone-inducible blocking factor (PIBF) and retinol-binding protein-4 (RBP-4) in patients with adenomyosis undergoing in vitro fertilization-embryo transfer (IVF-ET) assisted pregnancy and their predictive value for pregnancy outcomes.

Methods A total of 96 patients with adenomyosis who underwent IVF-ET assisted pregnancy were included as the study subjects, according to clinical pregnancy, the subjects were divided into clinical pregnancy group (56 cases) and non-pregnancy group (40 cases).The basic characteristics and treatment data, levels of serum PIBF and RBP-4 in the two groups were compared.The correlations of serum PIBF and RBP-4 with basal follicle stimulating hormone (FSH), anti-Mulerian hormone (AMH) and basal luteinizing hormone (LH) were analyzed by Pearson method.Multivariate logistic regression was applied to analyze the risk factors influencing the clinical pregnancy outcome of patients with adenomyosis by IVF-ET assisted pregnancy.Receiver operating characteristic (ROC) curve was used to analyze the predictive value of serum PIBF and RBP-4 levels for pregnancy outcome in IVF-ET assisted pregnancy with adenomyosis.

Results The basal FSH, AMH and dose of gonadotropin (Gn) in the clinical pregnancy group were greatly higher than those in the non-pregnant group (P < 0.05 to P < 0.01).The level of serum PIBF in the non-pregnancy group was greatly lower than that in the clinical pregnancy group (P < 0.01), and the level of RBP-4 was greatly higher than that in the clinical pregnancy group (P < 0.01).Correlation analysis showed that serum PIBF was positively correlated with basal FSH and AMH in adenomyosis patients (r=0.517, 0.669, P < 0.01), and serum RBP-4 was negatively correlated with basal FSH and AMH in adenomyosis patients (r=-0.558, -0.634, P < 0.01).Multivariate logistic analysis showed that low level of basal FSH, low level of AMH, low level of PIBF, and high level of RBP-4 were risk factors for clinical pregnancy outcomes of IVF-ET assisted pregnancy patients with adenomyosis (P < 0.05 to P < 0.01).The area under ROC curve (AUC) of the combined prediction of PIBF and RBP-4 for pregnancy outcomes in IVF-ET assisted pregnancy patients with adenomyosis was significantly greater than that of the AUC predicted by PIBF and RBP-4 alone (P < 0.05).

Conclusions The low level of serum PIBF and high level of RBP-4 were the risk factors affecting the pregnancy outcome of IVF-ET assisted pregnancy patients with adenomyosis, and the combination of the two has a certain predictive value for the pregnancy outcome of IVF-ET assisted pregnancy patients with adenomyosis.