Will the risk of stillbirth increase if you encounter extreme heat during pregnancy? This issue is becoming more and more concerned in the context of intensifying climate change. A prospective longitudinal study based on a Chinese birth cohort study involving more than 240,000 pregnant women gave a more refined answer: the key window period for high temperature exposure to increase the risk of stillbirth is not the entire pregnancy, but is concentrated at 32-36 weeks of gestation, especially at 35 weeks of gestation; What is even more surprising is that the high humidity environment did not exacerbate the harm of high temperatures, but showed an antagonistic effect - the risk of stillbirth in dry heat conditions was much higher than in humid heat conditions. This finding has important value for obstetric clinical guidance and public health policy formulation.
The latest research results of Professor Liu Ruixia's team from Beijing Obstetrics and Gynecology Hospital Affiliated to Capital Medical University were published in the authoritative journal "Environmental Research" in the field of environment. Based on the Chinese birth cohort study, the research team covered 334,924 pregnant women recruited from 52 hospitals in Chinese mainland between February 2018 and December 2022, and finally included 244,204 pregnancies after exclusion, including 243,262 live births and 942 stillbirths. Stillbirth is defined as a gestational age of ≥ 20 weeks and no signs of life at birth, excluding termination of pregnancy due to fetal abnormalities.