Maternal hyperuricemia and adverse maternal-fetal outcomes: a systematic review and meta-analysis of observational studies

Background Maternal serum uric acid (SUA) has been suggested as a biomarker for adverse pregnancy outcomes, but findings remain inconsistent. This systematic review and meta-analysis evaluated the association between elevated maternal SUA levels and key obstetric and neonatal outcomes. Methods A comprehensive search of PubMed, Scopus, Web of Science, and the Cochrane Library was conducted through December 2024. Observational studies reporting associations between high maternal SUA levels and pregnancy outcomes were included. Data were pooled using a random-effects model as odds ratios (ORs). Heterogeneity was assessed using the I 2 statistic. Results A total of 30 studies met the inclusion criteria. Elevated maternal SUA levels were significantly associated with increased odds of preterm birth (PTB; OR = 2.05, 95% CI: 1.55–2.72, I 2 = 90.22%, n = 20), preeclampsia (PE; OR = 3.84, 95% CI: 2.17–6.77, I 2 = 92.35%, n = 8), neonatal intensive care unit (NICU) admission (OR = 2.20, 95% CI: 1.63–2.97, I 2 = 0.00%, n = 5), cesarean delivery (OR = 1.44, 95% CI: 1.16–1.79, I 2 = 92.59%, n = 8), and intrauterine growth restriction (IUGR; OR = 3.03, 95% CI: 1.16–7.91, I 2 = 84.23%, n = 8). Elevated SUA levels were also associated with low Appearance, Pulse, Grimace, Activity, and Respiration scores at 1 min (OR = 3.63, 95% CI: 1.47–8.95, I 2 = 62.75%, n = 4) and 5 min (OR = 4.66, 95% CI: 2.45–8.85, I 2 = 0%, n = 4). Conversely, high SUA levels were associated with reduced odds of spontaneous vaginal delivery (SVD; OR = 0.68, 95% CI: 0.51–0.91, I 2 = 93.29%, n = 8) and a non-significant reduction in live birth (OR = 0.65, 95% CI: 0.41–1.02, I 2 = 55.98%, n = 4). Conclusion This meta-analysis shows an association between elevated maternal SUA levels and adverse maternal and neonatal outcomes. However, the evidence is derived from heterogeneous observational studies and does not support causal inference or routine SUA-based screening in clinical practice. Maternal SUA may be a promising biomarker, but large, well-designed prospective studies are needed to validate these findings and clarify its incremental predictive value. Systematic review registration CRD420251038421, https://www.crd.york.ac.uk/PROSPERO/view/CRD420251038421 .