Abstract
BACKGROUND: Prenatal exposure to meteorological factors and air pollutants may increase preterm birth (PTB) risk, but existing research is limited and inconsistent. Heilongjiang Province is located in Northeast China and is the northernmost and highest latitude province. Yet the association between meteorological factors, air pollutants, and PTB in this region remains unclear. METHODS: PTB cases were collected between July 1, 2019, and June 30, 2023. Meteorological factors were collected for the same period. The exposure-response relationships and lagged effects of meteorological factors and air pollutants on PTB were analyzed using the Distributed Lag Non-linear Model (DLNM), with a maximum lag of 30 days. RESULTS: A total of 3,267 PTB cases were included. Low and extremely low ambient temperatures were associated with an increased risk of PTB at lag day 20 (RR = 1.09, 95% CI: 1.01-1.18 and RR = 1.09, 95% CI: 1.02-1.16, respectively). In contrast, extremely high ambient temperatures were associated with an increased risk of PTB at lag day 0 (RR = 1.12, 95% CI: 1.00-1.25). An extremely high Humidex was associated with an increased risk of PTB at lag day 0 (RR = 1.15, 95% CI: 1.01-1.30). For ozone, each IQR increase (27.8 μg/m(3)) was associated with an increased risk of PTB, with the highest risk observed at lag day 0 (RR = 1.08, 95% CI: 1.01-1.15). CONCLUSION: This study indicated that extreme temperatures, as well as an extremely high Humidex and increased ozone concentrations, may be associated with an increased risk of PTB, with significant lag effects.