Department of Public Health, University of Copenhagen, Copenhagen, Denmark.
Research Institute of the McGill University Health Center, Montreal, Quebec, Canada.
Paediatr Perinat Epidemiol. 2023 Jan;37(1):45-56. doi: 10.1111/ppe.12918. Epub 2022 Aug 7.
Preterm birth is one of the most important contributors to neonatal mortality and morbidity. Experiencing stress during pregnancy may increase the risk of adverse birth outcomes, including preterm birth. This association has been observed in previous studies, but differences in measures used limit comparability.
The objective of the study was to investigate the association between two measures of maternal stress during pregnancy, life stress and emotional distress, and gestation duration.
Women recruited in the Danish National Birth Cohort from 1996 to 2002, who provided information on their stress level during pregnancy and expecting a singleton baby, were included in the study. We assessed the associations between the level of life stress and emotional distress in quartiles, both collected at 31 weeks of pregnancy on average, and the rate of giving birth using Cox regression within intervals of the gestational period.
A total of 80,991 pregnancies were included. Women reporting moderate or high levels of life stress vs no stress had a higher rate of giving birth earlier within all intervals of gestational age (e.g. high level: 27-33 weeks: hazard ratio (HR) 1.38, 95% confidence interval (CI) 1.04, 1.84; 34-36 weeks: 1.10, 95% CI 0.97, 1.25; 37-38 weeks: 1.21, 95% CI 1.15, 1.28). These associations between life stress and preterm birth were mainly driven by pregnancy worries. For emotional distress, a high level of distress was associated with shorter length of gestation in the preterm (27-33 weeks: 1.38, 95% CI 1.02, 1.86; 34-36 weeks: 1.05, 95% CI 0.91, 1.19) and early term (1.11, 95% CI 1.04, 1.17) intervals.
Emotional distress and life stress were shown to be associated with gestational age at birth, with pregnancy-related stress being the single stressor driving the association. This suggests that reverse causality may, at least in parts, explain the earlier findings of stress as a risk factor for preterm birth.
早产是导致新生儿死亡和发病的最重要因素之一。孕妇在孕期经历压力可能会增加不良分娩结局（包括早产）的风险。这一关联在之前的研究中已经得到了观察，但由于使用的测量方法不同，其可比性受到限制。
本研究旨在探讨孕期两种母体压力测量指标（生活压力和情绪困扰）与妊娠持续时间的关系。
该研究纳入了 1996 年至 2002 年参加丹麦国家出生队列的妇女，这些妇女在孕期提供了她们的压力水平信息，并预计会产下单胎。我们评估了在平均妊娠 31 周时收集的生活压力和情绪困扰四分位水平与分娩率之间的关系，并在妊娠期间的各个间隔内使用 Cox 回归进行分析。
共纳入 80991 例妊娠。与无压力相比，报告中等到高水平生活压力的女性在所有妊娠年龄间隔内更早分娩的比例更高（例如，高水平：27-33 周：风险比（HR）1.38，95%置信区间（CI）1.04-1.84；34-36 周：1.10，95%CI 0.97-1.25；37-38 周：1.21，95%CI 1.15-1.28）。这些生活压力与早产之间的关联主要是由妊娠担忧驱动的。对于情绪困扰，高水平的困扰与早产（27-33 周：1.38，95%CI 1.02-1.86；34-36 周：1.05，95%CI 0.91-1.19）和早期足月（1.11，95%CI 1.04-1.17）间隔的妊娠持续时间较短有关。
情绪困扰和生活压力与分娩时的胎龄有关，与妊娠相关的压力是驱动这种关联的唯一压力源。这表明，至少在一定程度上，反向因果关系可能解释了之前将压力视为早产风险因素的研究结果。
