Objectives To determine the causes of fetal death among the stillbirths using two classification systems from 22 weeks of gestation in a period of three years in high-risk pregnancies. This is a retrospective observational study. Methods The National Institute of Perinatal Health in Mexico City is a Level 3 care referral center attending high-risk pregnancies from throughout the country. The population consisted of patients with fetal death during a three-year period. Between January 2016 and December 2018, all stillbirths were examined in the Pathology Department by a pathologist and a medical geneticist. Stillbirth was defined as a fetal death occurring after 22 weeks of gestation. Results Main outcome measures: Causal analysis of fetal death using the International Statistical Classification of Disease and Related Health Problems-Perinatal Mortality (ICD-PM) and initial causes of fetal death (INCODE) classification systems. A total of 297 stillborn neonates were studied. The distribution of gestational age in antepartum stillbirths (55.2%) showed a bimodal curve, 36% occurred between 24 and 27 weeks and 32% between 32 and 36 weeks. In comparison, the majority (86%) of intrapartum deaths (44.8%) were less than 28 weeks of gestation. Of the 273 women enrolled, 93 (34%) consented to a complete fetal autopsy. The INCODE system showed a present cause in 42%, a possible cause in 54% and a probable cause in 93% of patients. Conclusions The principal causes of antepartum death were fetal abnormalities and pathologic placental conditions and the principal causes of intrapartum death were complications of pregnancy which caused a premature labor and infections.

中文翻译：

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高危妊娠胎儿死亡的原因分析


目的 使用两种分类系统确定三年内高危妊娠中从妊娠 22 周起死产的胎儿死亡原因。这是一项回顾性观察研究。方法 墨西哥城国家围产期健康研究所是一家三级护理转诊中心，负责全国各地的高危妊娠。该人群由三年内胎儿死亡的患者组成。 2016年1月至2018年12月期间，所有死产均在病理科由病理学家和医学遗传学家进行检查。死产被定义为妊娠 22 周后发生的胎儿死亡。结果 主要结果指标：使用国际疾病和相关健康问题统计分类 - 围产期死亡率 (ICD-PM) 和胎儿死亡初始原因 (INCODE) 分类系统对胎儿死亡进行因果分析。总共对 297 名死产新生儿进行了研究。产前死产的胎龄分布（55.2%）呈双峰曲线，36%发生在24至27周之间，32%发生在32至36周之间。相比之下，大多数 (86%) 产时死亡 (44.8%) 发生在妊娠 28 周以内。在 273 名登记的女性中，93 名 (34%) 同意接受完整的胎儿尸检。 INCODE 系统显示 42% 的患者存在当前原因，54% 的患者显示可能原因，93% 的患者显示可能原因。结论 产前死亡的主要原因是胎儿畸形和病理性胎盘状况，产时死亡的主要原因是妊娠并发症导致的早产和感染。