The incidence of adverse pregnancy outcomes has remained high in recent years, which poses a serious threat to maternal and neonatal life and health. Chronic stress is known to be a risk factor for adverse pregnancy outcomes, while the relationship between allostatic load (AL) as a composite physiological index of chronic stress, and adverse pregnancy outcomes has not been clarified.

To explore the effect of AL on adverse pregnancy outcomes in women in late pregnancy.

Women in late pregnancy who met the study requirements were recruited as study subjects by using the convenience sampling method from November 2021 to November 2022 in the obstetrics outpatient clinics of the 901 Hospital, Joint Logistic Support Force of the Chinese People's Liberation Army, Jin'an Maternal and Child Health Care Hospital. Basic information such as general and obstetric data were collected through questionnairs, biological indicators were collected through physical examination and laboratory tests, and AL scores of the study subjects were calculated by referring to AL-related literature; pregnancy outcome information was obtained by reviewing the hospital electronic medical record system. Multivariate Logistic regression analysis was used to explore the effect of AL on adverse pregnancy outcomes in women in late pregnancy.

A total of 354 women in late pregnancy with an average age of (29.3±4.1) years and upper quartile of AL total score of 3 were included in this study. The upper quartile of the total AL score of the study subjects was used as the high-risk threshold, and they were divided into low-level AL (AL <3) and high-level AL (AL ≥3) according to their AL scores. High AL pregnant women accounted for 32.8% (116/354) and low AL pregnant women accounted for 67.2% (238/354). The prevalence of adverse pregnancy outcomes was 15.5% (55/354), including 9.9% (35/354) of macrosomia, followed by preterm birth〔5.4% (19/354) 〕and low birth weight〔2.3% (8/354) 〕. The incidence of adverse pregnancy outcomes was higher in women in late pregnancy with high AL (26.7%, 31/116) than in women in late pregnancy with low AL (10.1%, 24/238) (P<0.05) ; the incidence of preterm birth (10.3%, 12/116) and delivery of macrosomia (15.5%, 18/116) was higher in women in late pregnancy with high AL than in women in late pregnancy with low AL (2.9%, 7/238; 7.1%, 17/238) (P<0.05). Multivariate Logistic regression analysis showed that women in late pregnancy with high AL had a 2.465-fold increased risk of adverse pregnancy outcomes compared to women in late pregnancy with low AL〔95%CI (1.315, 4.622), P<0.05〕. High AL level was a risk factor for preterm birth〔OR=4.832, 95%CI (1.545, 15.114) 〕and delivery of macrosomia〔OR=2.868, 95%CI (1.392, 5.909) 〕in women in late pregnancy compared to low AL level (P<0.05) .

High level of AL in women in late pregnancy increase the risk of adverse pregnancy outcomes, especially the risk of preterm birth and delivery of macrosomia. Attention to AL in women during pregnancy should be enhanced to provide a theoretical basis for preventing adverse pregnancy outcomes.

近年来不良妊娠结局的发生率居高不下，对孕产妇和新生儿的生命健康构成了严重威胁。已知慢性压力是不良妊娠结局的危险因素之一，而非稳态负荷（AL）作为衡量慢性应激的综合生理指标，与不良妊娠结局的关系尚未明确。

探讨妊娠晚期女性AL对不良妊娠结局的影响。

采用便利抽样法于2021年11月—2022年11月在中国人民解放军联勤保障部队第901医院、六安市金安区妇幼保健院产科门诊招募符合研究要求的妊娠晚期女性作为研究对象。通过问卷调查收集其一般资料和产科资料等基本资料；通过体格检查和实验室检查收集生物学指标，并参考AL相关文献计算研究对象的AL得分；通过查阅医院电子病历系统获得妊娠结局资料。采用多因素Logistic回归分析探究AL对妊娠晚期女性不良妊娠结局的影响。

本研究共纳入妊娠晚期女性354例，平均年龄（29.3±4.1）岁，AL总分的上四分位数为3分。本研究以研究对象AL总分的上四分位数为高风险临界值，将其按照AL得分分为低水平AL（AL<3分）和高水平AL（AL≥3分）。高水平AL孕妇占32.8%（116/354），低水平AL孕妇占67.2%（238/354）。不良妊娠结局发生率为15.5%（55/354），其中巨大儿发生率为9.9%（35/354），其次为早产〔5.4%（19/354）〕、低出生体质量〔2.3%（8/354）〕。高水平AL妊娠晚期女性不良妊娠结局发生率（26.7%，31/116）高于低水平AL妊娠晚期女性（10.1%，24/238）（P<0.05）；高水平AL妊娠晚期女性早产发生率（10.3%，12/116）、娩出巨大儿率（15.5%，18/116）高于低水平AL妊娠晚期女性（2.9%，7/238；7.1%，17/238）（P<0.05）。多因素Logistic回归分析结果显示，高水平AL妊娠晚期女性发生不良妊娠结局的风险比低水平AL妊娠晚期女性增加2.465倍〔95%CI（1.315，4.622），P<0.05〕。与低水平AL相比，高水平AL是妊娠晚期女性早产〔OR=4.832，95%CI（1.545，15.114）〕、娩出巨大儿〔OR=2.868，95%CI（1.392，5.909）〕的危险因素（P<0.05）。

妊娠晚期女性高水平AL会增加不良妊娠结局的发生风险，尤其易发生早产和娩出巨大儿，应加强对妊娠期女性AL的关注。