To evaluate the predictive value of contrast injection pressure during hysterosalpingography (HSG) for non-in vitro fertilization (IVF)-assisted pregnancy.

This study enrolled 318 patients with tubal infertility who underwent HSG at Women's Hospital of Nanjing Medical University between January 2024 and February 2025. Injection pressure at contrast spillage from the fimbrial end during HSG was recorded. Patients were followed for 1 year. Among them, 267 reached the endpoint and 243 completed follow-up. The association between injection pressure and pregnancy was analyzed.

The competing risk model showed that injection pressure had a significant negative effect on non-IVF pregnancy (P=0.001). ROC curve analysis showed that the area under the curve of injection pressure for predicting non-IVF pregnancy was 0.715(95% CI: 0.651-0.778, P<0.001), and the exploratory threshold was 45 kPa. When divided into low-pressure group (≤45 kPa, n=141) and high-pressure group (>45 kPa, n=69) according to 45 kPa, the non-IVF pregnancy rate in the high-pressure group was significantly lower than that in the low-pressure group (P=0.004).

Injection pressure during HSG is inversely associated with pregnancy. The exploratory threshold of 45 kPa may serve as a potential reference for generating clinical hypotheses regarding risk stratification, providing direction for individualized precision medicine. However, validation through multicenter prospective studies is required.