Pregnancy outcomes in patients with type 1 diabetes in China: a retrospective study

Abstract

BackgroundSparse data on pregnancy outcomes for women with type 1 diabetes exist in Chinese women. We aimed to investigate maternal, perinatal, and fetal and neonatal outcomes in women with type 1 diabetes in China. MethodWe did a retrospective study in 11 hospitals in Beijing, Jinan, Nanjing, Shanghai, Chengdu, Changsha, Guangzhou. We compiled data on pregnancy outcomes of women with type 1 diabetes from anonymised medical records of maternal and infant birth between Jan 1, 2004, to Dec 31, 2014. We analysed perinatal maternal mortality, perinatal neonatal mortality, and perinatal birth defect rate. These outcomes in the general population were estimated from the annual report of national health statistic and the report of birth defects in China. We used χ2 or Fisher's exact test for statistical analyses of categorical data. Ethics approval was granted by all the participating hospitals. FindingsWe included 289 women with type 1 diabetes with a singleton pregnancy, of whom 26 (9%) had a history of adverse pregnancy outcomes at the start of the study period. At start of pregnancy, mean age was 27·6 years (SD 4·2) and mean diabetes duration was 5·26 years (SD 5·49). Nine women were excluded because of elective terminations and 15 were excluded because no data on pregnancy outcomes were available; thus, 265 women were included in the analysis. In patients with HbA1c records available, 41 (57%) of 72 achieved the preconception HbA1c target (≤7·0%; ie, 53·00 mmol/mol), and 49 (38%) of 130 achieved the third trimester HbA1c target (≤6·0 %; ie, 42 mmol/mol). Nine (3%) pregnancy losses were recorded in the first trimester, 20 (8%, including ten stillbirths) in the second trimester, and six (2%) in the third trimester. Main adverse maternal outcomes were procession of diabetic complications (30 [11%] women), pre-eclampsia or eclampsia (47 [18%]), and total pregnancy losses (35 [13%]). Of 230 livebirths, 44 (19%) preterm births, 12 (5%) cardiac congenital malformations, and 18 (8%) early neonatal deaths were recorded. Of 236 infants (230 livebirths and 6 stillbirths in the third trimester), main adverse neonatal outcomes were large for gestational age (68 [29%]) and small for gestational age (12 [5%]); 96 (41%) had to admitted to the neonatal department. Overall, perinatal maternal mortality was 423·73 (95% CI 397·18–451·12) per 100 000 person-years, perinatal neonatal mortality was 55·08% (54·14–56·04), and the incidence of birth defects was 847·45 (835·92–859·05) per 100 000 person-years. Birth defects were the leading cause of neonatal perinatal deaths (10 [29%] of 34). Compared with the general population in China, women with type 1 diabetes did not have increased perinatal maternal mortality (risk ratio 11·76, 95% CI 1·65–83·78; p=0·082), but their infants had significantly higher risks of perinatal mortality (risk ratio 7·58, 95% CI 4·33–13·26; p<0·0001) and birth defects (8·43, 5·33–13·33; p<0·0001). InterpretationAdverse pregnancy outcomes are more frequent in women with type 1 diabetes than in the general population. Management of type 1 diabetes in pregnant women needs to be improved. FundingChinese National Health and Family Planning Commission Foundation for Public Welfare Industry Research Project (201502011), Sun Yat-Sen University Clinical Research 5010 Program (2007030), and World Diabetes Foundation (WDF14-921).