Effects of medical co-morbidities on severe maternal morbidities in China: a multicenter clinic register study

Abstract

Objective: To investigate the incidence of severe maternal morbidities (SMM) in China and explore effects of medical co-morbidities on SMM.

Design: Proactive multicenter clinic register collaboration.

Setting: Data on all deliveries at eight hospitals in Sichuan province, China, collected from 1 January 2009 to 12 December 2010.

Population: 33 993 delivering women and 34 547 live births.

Methods: We defined SMM as a combination indicator of severe maternal complications, critical interventions, admission to the intensive care unit and maternal near-miss instances. We randomly selected 80% of the data from the entire database to build a logistic regression model. The remaining 20% were used to test the predictive power of the model.

Main outcome measures: SMM incidence, adjusted odds ratios (aORs), and area under a receiver operating characteristic (ROC) curve.

Results: Severe maternal morbidities incidence was 43.4/1000 live births [confidence interval (CI) 41.24-45.56]. Fifteen variables were independent contributors to the model. Seven medical co-morbidities significantly affected the occurrence of SMM, including iron-deficiency anemia (aOR 3.07, CI 2.47-3.83) and other hematological diseases (aOR 5.82, CI 3.50-9.69), hepatitis-B virus infection (aOR 1.48, CI 1.12-1.97) and other hepatic diseases (aOR 3.81, CI 1.61-9.04), cardiopathy (aOR 3.59, CI 2.62-4.93), hypertension (aOR 5.23, CI 4.06-6.75), and respiratory diseases (aOR 2.10, CI 1.25-3.52). The area under the ROC curve was 0.8127.

Conclusions: The incidence of SMM was typical of a low resource area. There is a need to identify medical co-morbidities and to adopt prophylactic measures and interventions.

Keywords: China; Severe maternal morbidities; logistic regression model; medical co-morbidities; multicenter clinic register study.