BACKGROUND As the rate of cesarean section delivery has increased, the incidence of severe maternal morbidity continues to increase. Severe maternal morbidity is associated with high medical costs, extended length of hospital stay, and long-term rehabilitation. However, there is no evidence whether severe maternal morbidity affects postpartum readmission. Therefore, this study aimed to determine the relationship between severe maternal morbidity and postpartum readmission. METHODS This nationwide population-based cohort study used the Korean National Health Insurance Service-National Sample cohort of 90,035 delivery cases between January 2003 and November 2013. The outcome variable was postpartum readmission until 6 weeks after the first date of delivery in the hospital. Another variable of interest was the occurrence of severe maternal morbidity, which was determined using the Center for Disease Control and Prevention's algorithm. The Cox proportional hazard model was used to assess the association between postpartum readmission and severe maternal morbidity after all covariates were adjusted. RESULTS The overall incidence of postpartum readmission was 2041 cases (0.95%) of delivery. Women with severe maternal morbidity had an approximately 2.4 times higher risk of postpartum readmission than those without severe maternal morbidity (hazard ratio 2.36, 95% confidence interval 1.75-3.19). In addition, compared with reference group, women who were aged 20-30 years, nulliparous, and delivered in a tertiary hospital were at high risk of postpartum readmission. CONCLUSIONS Severe maternal morbidity was related to the risk of postpartum readmission. Policy makers should provide a quality indicator of postpartum maternal health care and improve the quality of intrapartum care.

中文翻译：

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韩国妇女的严重孕产妇发病率与产后再次入院风险之间的关系：一项基于全国人口的队列研究。

背景技术随着剖宫产率的增加，严重的母亲发病率继续增加。严重的母亲发病与高昂的医疗费用，较长的住院时间和长期康复有关。但是，没有证据表明严重的孕产妇发病率是否会影响产后再入院。因此，本研究旨在确定严重的母亲发病率与产后再入院之间的关系。方法这项基于全国人群的队列研究使用了2003年1月至2013年11月之间的90035例分娩病例的韩国国家健康保险服务-国家样本队列。结局变量为产后再次入院，直至首次分娩后6周。另一个有趣的变量是严重的孕产妇发病，使用疾病预防控制中心的算法确定。校正所有协变量后，使用Cox比例风险模型评估产后再入院率与严重孕产妇发病率之间的关联。结果产后再入院的总发生率为2041例（0.95％）分娩。患有严重孕产妇疾病的妇女产后再次入院的风险比没有严重孕产妇疾病的妇女高约2.4倍（风险比2.36，95％置信区间1.75-3.19）。此外，与参考组相比，年龄在20-30岁，未生育并在三级医院分娩的妇女有较高的产后再入院风险。结论严重的母亲发病与产后再入院的风险有关。