Relationship between fasting plasma glucose in middle and last trimester and gestational diabetes mellitus:analysis of 18 851 cases / 中华围产医学杂志

ABSTRACT

Objective To explore the feasibility of excluding oral 75 g glucose tolerance test (OGTT)in pregnant women with fasting plasma glucose (FPG) ＜4.4 mmol/L in middle and late trimester.Methods From February 1,2012 to August 31,2013,18 851 pregnant women without pre-gestational diabetes mellitus who received 75 g OGTT in Maternal and Child Health Hospital of Hubei Province,China,at 24-28 weeks of gestation were enrolled.The criteria for gestational diabetes mellitus (GDM) were FPG ＞5.1 mmol/L and/or 1 h plasma glucose ＞10.0 mmol/L and/or 2 h plasma glucose ＞8.5 mmol/L in OGTT.The values of FPG in predicting GDM were analyzed with receiver operating characteristic (ROC) curve.The differences of detection rates for GDM among women of different ages,women with different FPG levels,and those with or without risk factors of GDM were compared by x2 test and Fisher's exact test.Results The overall detection rate of GDM was 9.11％(1 718/18 851).The detection rate of GDM was lower in women aged ＜ 25 years than women aged 25-,30-and ≥ 35 years [4.77％ (137/2 875) vs 7.76％ (803/10 350),12.43％ (552/4 440)and 19.06％ (226/1 186),respectively,x2=30.53,120.24 and 210.66,all P＜0.01].The sensitivity and specificity were 55％ and 68％,respectively,when the cutoff value of FPG was 4.4 mmol/L,and the Youden index was 0.23 and the area under the ROC curve was 0.61 (95％CI0.59-0.63,P＜0.01).The sensitivity and specificity were 40％ and 80％,respectively,when the cutoff value was 4.5 mmol/L,and the Youden index was 0.20 and the area under the ROC curve was 0.61 (95％CI0.59-0.63,P＜0.01).The missed diagnosis rate was lower when the cutoff point of FPG was defined as 4.4 mmol/L.The detection rate for GDM was 3.45％ (384/11 121) in women with FPG ＜4.4 mmol/L,significantly lower than in those with FPG ≥ 4.4 but ＜5.1 mmol/L and ≥ 5.1 mmol/L [8.06％ (561/6 957) and 100.00％ (773/773),x2=183.66 and 7 672.08,all P＜0.01].When FPG was ＜4.4 mmol/L or ≥ 4.4 but ＜5.1 mmol/L,the detection rate for GDM was significantly higher in women with GDM risk factors than in those without [5.09％ (118/2 318) and 10.75％ (184/1 712) vs 3.02％ (266/8 803) and 7.19％ (377/5 245),x2=23.56 and 22.06,P＜0.01].Conclusion OGTT may not be included in GDM screening in the pregnant women with FPG＜4.4 mmol/L and without GDM risk factors in the areas lack of medical resources.