A new New Zealand study reports an association between prenatal exposure to nitrate in drinking water and premature births. Researchers analysed data for 735,800 births recorded between 2008 and 2021, examining whether exposure to nitrate in water was linked to earlier-than-expected delivery. The study estimates that, on average, about 120 premature births each year could be attributed to nitrate exposure. Both outlets describe the findings as stemming from large-scale analysis of birth records and drinking-water nitrate exposure. The research therefore focuses on pregnancy outcomes during a multi-year period and provides a quantification of potential impact at the population level. The results are presented as an evidence base for understanding how environmental factors may relate to birth outcomes, rather than as a statement that nitrate definitively causes prematurity. The findings are reported as a “major” or “landmark” study, reflecting the scale of the dataset used.