Department of Epidemiology, College of Human Medicine, Michigan State University, East Lansing, MI 48824, USA.
BJOG. 2010 Mar;117(4):445-55. doi: 10.1111/j.1471-0528.2009.02472.x. Epub 2010 Jan 14.
To evaluate evidence of placental haemorrhage (PH) obtained through maternal interviews, patient charts and placental pathology examinations as potential indicators of a 'bleeding pathway' to preterm delivery (PTD).
Prospective cohort.
Fifty-two clinics in five communities in Michigan, USA (1998-2004).
A subset (n = 996) of cohort participants with complete placental pathology data.
First-trimester bleeding and placental abruption were ascertained by mid-trimester interviews and chart review, respectively. Disc-impacting blood clot was defined as a gross placental examination finding of a blood clot impacting adjacent tissue. Microscopic haemorrhage was defined as 'high' (top quintile) scores on an aggregate measure of placental pathology findings suggestive of atypical maternal vessel haemorrhage. These four PH indicators were compared with one another and with risk of PTD assessed by logistic regression analyses.
Preterm delivery and PTD subtypes (i.e. <35 weeks, 35-36 weeks; spontaneous, medically indicated) compared with term deliveries.
Placental abruption cases had 2.3-fold to 5.5-fold increased odds of the other three PH indicators. Disc-impacting blood clots and microscopic haemorrhage were associated with one another (odds ratio [OR] = 4.6), but not with first-trimester bleeding. In a multivariable model that included all four PH indicators and confounders, risk of PTD < 35 weeks was elevated with first-trimester bleeding (OR = 1.9 [1.0, 3.4]), placental abruption (OR = 5.2 [1.7, 16.2]), disc-impacting blood clots (OR = 2.3 [1.0, 5.0]) and microscopic haemorrhage (OR = 2.4 [1.4, 4.2]).
Multiple clinical and subclinical PH indicators are associated with PTD, particularly early PTD.
评估通过产妇访谈、病历和胎盘病理学检查获得的胎盘出血（PH）证据，作为早产（PTD）“出血途径”的潜在指标。
前瞻性队列研究。
美国密歇根州 5 个社区的 52 个诊所（1998-2004 年）。
具有完整胎盘病理学数据的队列参与者的一个子集（n=996）。
通过中孕期访谈和病历回顾分别确定早孕出血和胎盘早剥。盘状撞击性血块定义为大体胎盘检查发现血块撞击相邻组织。显微镜下出血定义为胎盘病理学检查结果提示非典型母体血管出血的综合指标的“高”（五分位最高）评分。将这四个 PH 指标相互比较，并通过逻辑回归分析评估与 PTD 风险的关系。
早产和 PTD 亚型（即<35 周、35-36 周；自发性、医学指征）与足月分娩比较。
胎盘早剥病例其他三个 PH 指标的优势比（OR）为 2.3 倍至 5.5 倍。盘状撞击性血块和显微镜下出血相互关联（OR=4.6），但与早孕出血无关。在一个包含所有四个 PH 指标和混杂因素的多变量模型中，PTD<35 周的风险随着早孕出血（OR=1.9[1.0，3.4]）、胎盘早剥（OR=5.2[1.7，16.2]）、盘状撞击性血块（OR=2.3[1.0，5.0]）和显微镜下出血（OR=2.4[1.4，4.2]）而升高。
多种临床和亚临床 PH 指标与 PTD 相关，尤其是早期 PTD。
