Elevated serum uric acid before 20 weeks of gestation increases the risk of preeclampsia

This study aimed to investigate the association between serum uric acid level before gestational age of 20 weeks and preeclampsia. This study included pregnant women of three hospitals from January 2018 to June 2024. Clinical data were extracted using electronic medical record systems. The exposure factor was serum uric acid measured before gestational age of 20 weeks, with the primary outcome being preeclampsia, and secondary outcomes being preterm birth. Smooth curve fitting, ROC analysis, threshold effects, multivariate logistic regression, and subgroup analysis were employed to examine the relationship between uric acid and preeclampsia. The Kaplan-Meier method and log-rank test were used to evaluate the impact of serum uric acid on the gestational age at delivery. A total of 44,609 singleton pregnancies were included. There was a nonlinear relationship between serum uric acid level and the risk of preeclampsia, with a turning point at a uric acid level of 240 µmol/L. After adjusting for confounders, compared to non-preeclampsia cases, the risk of preeclampsia increased 1.38 times (95% CI: 1.28-1.48) for uric acid level between 240~360 µmol/L and 2.14 times (95% CI: 1.61-2.85) for UA levels ≥ 360 µmol/L. Similar positive associations were observed between uric acid level and preterm birth. Subgroup analysis maintained this positive correlation. Interaction tests indicated that BMI might influence the strength of the association between uric acid and preeclampsia (P < 0.05). Elevated serum uric acid level before gestational age of 20 weeks increase the risk of preeclampsia. Elevated uric acid levels in early pregnancy are associated with an increased risk of preeclampsia, suggesting that monitoring uric acid may help identify women at higher risk.