Inflammation markers SII and SIRI show potential for early gestational diabetes risk detection, but evidence remains inconclusive

Two inflammation-based blood markers, SII and SIRI, may help identify women at higher risk of gestational diabetes, though current evidence is limited and more research is needed before they can be used routinely in clinical practice.

New research suggests two inflammation-based blood markers may help identify women at higher risk of gestational diabetes, though the evidence is still uneven and not yet ready for routine clinical use.

A systematic review and meta-analysis published in the International Journal of Gynaecology and Obstetrics pooled nine studies involving 67,068 participants and found that both the systemic immune-inflammation index, or SII, and the systemic inflammation response index, or SIRI, were associated with a greater likelihood of gestational diabetes mellitus. The analysis found modest but statistically significant links in both continuous and categorical comparisons, with higher values of each marker tracking with higher risk. However, the researchers also noted substantial differences between studies, which means the results should be interpreted cautiously.

The findings add to a growing body of work pointing to inflammation as a possible feature of gestational diabetes. A separate meta-analysis indexed in PubMed found that women with gestational diabetes had significantly higher SII values than women without the condition, but the same pattern was not seen for pre-eclampsia. Another review published by MDPI reported that higher first-trimester SII and SIRI levels were linked not only to gestational diabetes but also to pre-eclampsia, although the estimated risk increases were relatively modest. Meanwhile, a multicentre retrospective study of 47,480 singleton pregnancies found a dose-dependent relationship between early-pregnancy SII and gestational diabetes, with the highest quartile carrying a notably higher risk than the lowest.

Taken together, the studies suggest that these inflammation markers may eventually have a role in early risk assessment, especially because they are derived from routine blood counts and are relatively easy to calculate. But the new review also highlights an important limitation: the association for continuous SIRI values was less stable than the others, and the variability between studies remains a major obstacle. That makes the current evidence more suggestive than definitive, and it leaves open questions about how these markers would perform alongside established clinical risk factors such as body mass index, family history and previous pregnancy complications.

For now, the message is that SII and SIRI look promising as low-cost indicators of inflammatory activity linked to gestational diabetes, but larger and more standardised studies will be needed before they can be used confidently in screening or prediction.