Wei Yuhao, Jiang Xiaomin, Li Huimin, Zhang Qing, Hua Linlin, Dong Jing, Xu Jihong, Yang Ying, Wang Qiaomei, Shen Haiping, Zhang Yiping, Yan Donghai, Peng Zuoqi, Kan Haidong, Ma Xu, Cai Jing, He Yuan
School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and NHC Key Lab of Health Technology Assessment, Fudan University, Shanghai 200032, China.
Department of Obstetrics, Anhui Province Hefei Maternity and Child Health Hospital, Hefei, Anhui 230001, China; Department of Obstetrics, Maternity and Child Healthcare Hospital Affiliated to Anhui Medical University, Hefei, Anhui 230032, China.
Environ Int. 2025 Apr;198:109430. doi: 10.1016/j.envint.2025.109430. Epub 2025 Apr 5.
Little is known about how temperature variability (TV) affects the risk of preterm birth (PTB).
This cohort study aims to evaluate the associations of prenatal TV exposure with gestational age and PTB risk.
This study included 3,012,744 live singleton births from 336 Chinese cities delivered between January 2013 and December 2015. TV exposure, indicating by standard deviation of temperature (SDT) and diurnal temperature range (DTR), were assessed by spatiotemporal models. Cox proportional hazard regression models were used to analyze the associations of PTB risk with TV exposure during the entire pregnancy and specific trimesters. Multivariate linear regressions were used to assess the associations between TV exposure and gestational age.
During the entire pregnancy, each 1 °C incremental in SDT and DTR was associated with a reduction in gestational age by 0.98 day (95 % confidence interval (CI), 0.89-1.06) and 0.36 day (95 % CI, 0.32-0.39). These increases in TV were also linked to a 20.1 % higher risk of PTB (hazard ratio [HR]: 1.201; 95 % CI: 1.182-1.233) for SDT and a 7.3 % higher risk of PTB (HR: 1.073; 95 % CI: 1.064-1.081) for DTR. The risk associated with TV was greater for very PTB than moderate and late PTB. Non-linear exposure-response curves indicated a monotonic increase in HRs for PTB with higher TV exposure, with the curves becoming less steep beyond an inflection point. These associations seemed to be more pronounced in women who lived in rural areas and in the climate zone of tropical monsoon, and gave birth in winter compared to their counterparts.
TV was associated with higher PTB risk and shortened gestational age in China.
关于温度变异性（TV）如何影响早产（PTB）风险，人们了解甚少。
这项队列研究旨在评估产前TV暴露与孕周及PTB风险之间的关联。
本研究纳入了2013年1月至2015年12月期间在中国336个城市出生的3,012,744例单胎活产。通过时空模型评估TV暴露，以温度标准差（SDT）和昼夜温度范围（DTR）表示。采用Cox比例风险回归模型分析整个孕期及特定孕期TV暴露与PTB风险的关联。采用多元线性回归评估TV暴露与孕周之间的关联。
在整个孕期，SDT每增加1°C与孕周缩短0.98天相关（95%置信区间（CI），0.89 - 1.06），DTR每增加1°C与孕周缩短0.36天相关（95% CI，0.32 - 0.39）。TV的这些增加还与SDT导致的PTB风险升高20.1%（风险比[HR]：1.201；95% CI：1.182 - 1.233）以及DTR导致的PTB风险升高7.3%（HR：1.073；95% CI：1.064 - 1.081）相关。与极早产相比，TV与中度和晚期早产相关的风险更大。非线性暴露 - 反应曲线表明，随着TV暴露增加，PTB的HR呈单调增加，超过拐点后曲线变缓。与居住在农村地区、热带季风气候区且在冬季分娩的女性相比，这些关联在其对应人群中似乎更为明显。
在中国，TV与较高的PTB风险和缩短的孕周相关。
