Abstract：
UNASSIGNED: Low birthweight (LBW) is when an infant is born too soon or too small, and it affects one in seven infants in low- and middle-income countries. LBW has a significant impact on short-term morbidity and mortality, and it impairs long-term health and human capital. Antenatal microbial and inflammatory exposure may contribute to LBW.
UNASSIGNED: Ovid-Medline, Embase and Cochrane databases were searched for English-language articles evaluating inflammatory, microbial or infective causes of LBW, small-for-gestational age, intra-uterine growth restriction or prematurity. Inclusion criteria were human studies including published data; conference abstracts and grey literature were excluded. A narrative synthesis of the literature was conducted.
UNASSIGNED: Local infections may drive the underlying causes of LBW: for example, vaginitis and placental infection are associated with a greater risk of prematurity. Distal infection and inflammatory pathways are also associated with LBW, with an association between periodontitis and preterm delivery and environmental enteric dysfunction and reduced intra-uterine growth. Systemic maternal infections such as malaria and HIV are associated with LBW, even when infants are exposed to HIV but not infected. This latter association may be driven by chronic inflammation, co-infections and socio-economic confounders. Antimicrobial prophylaxis against other bacteria in pregnancy has shown minimal impact in most trials, though positive effects on birthweight have been found in some settings with a high infectious disease burden.
UNASSIGNED: Maternal inflammatory and infective processes underlie LBW, and provide treatable pathways for interventions. However, an improved understanding of the mechanisms and pathways underlying LBW is needed, given the impact of LBW on life-course.
UNASSIGNED: Ovid-Medline, Embase and Cochrane databases were searched for English-language articles evaluating inflammatory, microbial or infective causes of LBW, small-for-gestational age, intra-uterine growth restriction or prematurity. Inclusion criteria were human studies including published data; conference abstracts and grey literature were excluded. A narrative synthesis of the literature was conducted.
UNASSIGNED: Local infections may drive the underlying causes of LBW: for example, vaginitis and placental infection are associated with a greater risk of prematurity. Distal infection and inflammatory pathways are also associated with LBW, with an association between periodontitis and preterm delivery and environmental enteric dysfunction and reduced intra-uterine growth. Systemic maternal infections such as malaria and HIV are associated with LBW, even when infants are exposed to HIV but not infected. This latter association may be driven by chronic inflammation, co-infections and socio-economic confounders. Antimicrobial prophylaxis against other bacteria in pregnancy has shown minimal impact in most trials, though positive effects on birthweight have been found in some settings with a high infectious disease burden.
UNASSIGNED: Maternal inflammatory and infective processes underlie LBW, and provide treatable pathways for interventions. However, an improved understanding of the mechanisms and pathways underlying LBW is needed, given the impact of LBW on life-course.
摘要：
■低出生体重（LBW）是指婴儿出生太快或太小，它影响低收入和中等收入国家七分之一的婴儿。低出生体重对短期发病率和死亡率有显著影响，它损害了长期健康和人力资本。产前微生物和炎症暴露可能导致LBW。
■Ovid-Medline,在Embase和Cochrane数据库中搜索评估炎症的英文文章，LBW的微生物或感染性原因，小于胎龄，子宫内生长受限或早产。纳入标准是人体研究，包括已发表的数据；会议摘要和灰色文献被排除在外。对文献进行了叙事综合。
■局部感染可能导致LBW的根本原因：例如，阴道炎和胎盘感染与更大的早产风险相关。远端感染和炎症途径也与LBW相关，与牙周炎和早产以及环境肠道功能障碍和子宫内生长减少有关。疟疾和艾滋病毒等系统性孕产妇感染与LBW相关，即使婴儿暴露于艾滋病毒但未被感染。后一种关联可能是由慢性炎症驱动的，共同感染和社会经济混杂因素。在大多数试验中，对怀孕期间其他细菌的抗菌预防作用最小。尽管在一些传染病负担较高的环境中发现了对出生体重的积极影响。
■产妇炎症和感染过程是LBW的基础，并为干预提供可治疗的途径。然而,需要更好地理解LBW的机制和途径，考虑到LBW对生命历程的影响。
■Ovid-Medline,在Embase和Cochrane数据库中搜索评估炎症的英文文章，LBW的微生物或感染性原因，小于胎龄，子宫内生长受限或早产。纳入标准是人体研究，包括已发表的数据；会议摘要和灰色文献被排除在外。对文献进行了叙事综合。
■局部感染可能导致LBW的根本原因：例如，阴道炎和胎盘感染与更大的早产风险相关。远端感染和炎症途径也与LBW相关，与牙周炎和早产以及环境肠道功能障碍和子宫内生长减少有关。疟疾和艾滋病毒等系统性孕产妇感染与LBW相关，即使婴儿暴露于艾滋病毒但未被感染。后一种关联可能是由慢性炎症驱动的，共同感染和社会经济混杂因素。在大多数试验中，对怀孕期间其他细菌的抗菌预防作用最小。尽管在一些传染病负担较高的环境中发现了对出生体重的积极影响。
■产妇炎症和感染过程是LBW的基础，并为干预提供可治疗的途径。然而,需要更好地理解LBW的机制和途径，考虑到LBW对生命历程的影响。
