[Characteristics of pre-gestational diabetes mellitus diagnosed during pregnancy and the effects on pregnancy outcomes].

Objective: To analyze the characteristics of pre-gestational diabetes mellitus (PGDM) diagnosed during pregnancy (missed diagnosis before pregnancy), and to evaluate the effects of diagnostic time on pregnancy outcomes. Methods: A retrospective study of 746 pregnant women who were diagnosed PGDM and delivered in Peking University First Hospital from January 1st, 2005 to December 31st, 2015 was conducted. The patients were divided into 2 group. Those diagnosed PGDM before pregnancy were defined as Group diagnosed before pregnancy, and those diagnosed during pregnancy were defined as Group diagnosed during pregnancy. In Group diagnosed during pregnancy, those diagnosed before 24 gestational weeks were defined as Group diagnosed during pregnancy A, and those diagnosed after 24 weeks were defined as Group diagnosed during pregnancy B. The prevalence of adverse pregnancy outcomes in each group were analyzed. Results: (1) Rate of missed diagnosis for PGDM: the incidence of PGDM diagnosed before pregnancy was 32.2% (240/746), and those diagnosed during pregnancy (missed diagnosis before pregnancy) was 67.8% (506/746). (2) Blood glucose control during pregnancy: ①Group diagnosed before pregnancy and Group diagnosed during pregnancy: the highest glycosylated hemoglobin (HbA1c) in Group diagnosed before pregnancy was (6.6±1.1)%, higher than that in Group diagnosed during pregnancy [(6.3±1.0)%, P=0.019]. However, there was no significant difference in the average HbA1c level between the 2 groups (P=0.616). The insulin needed percentage [90.8%(218/240) vs. 53.8%(272/506)] in Group diagnosed before pregnancy were higher than that in Group diagnosed during pregnancy (P<0.01). ②Group diagnosed during pregnancy A and B: the highest HbA1c in Group diagnosed during pregnancy A was (6.9±1.3)%, higher than that in Group diagnosed during pregnancy B [(6.1±0.8)%, P<0.05]. And the average HbA1c in Group diagnosed during pregnancy A [(6.4±0.8)%] was also higher than that in Group diagnosed during pregnancy B [(6.0±0.8)%, P<0.05]. In Group diagnosed during pregnancy B, 46.1% (187/406) used insulin, lower than the percentage in Group diagnosed during pregnancy A (85.0%, 85/100; P<0.01). ③There were no significant differences in the highest HbA1c and the average HbA1c between Group diagnosed during pregnancy A and Group diagnosed before pregnancy (P=0.020, P=0.037). There was neither no significant difference in the percentage used insulin during pregnancy between them (P=0.128). There were significant differences in the highest HbA1c and the average HbA1c between Group diagnosed during pregnancy B and Group diagnosed before pregnancy (P<0.01, P=0.014). There was also significant difference in the percentage used insulin during pregnancy between them (P<0.01). (3) Pregnancy outcome: ①Group diagnosed before pregnancy and Group diagnosed during pregnancy: the cesarean section rate [72.5% (174/240) vs. 59.7% (302/506)] in Group diagnosed before pregnancy were higher than those in Group diagnosed during pregnancy (P<0.01). However, there were no significant differences in preterm birth rate, pre-eclampsia, macrosomia percentage, percentage of neonates being hospitalized between the 2 groups (P=0.546, P=1.000, P=0.671, P=0.804) . ②There was no significant difference in preterm birth rate,cesarean delivery rate, macrosomia percentage, pre-eclampsia rate, percentage of neonates being hospitalized between Group diagnosed during pregnancy A and Group diagnosed during pregnancy B (P=0.887, P=0.495, P=0.841, P=1.000, P=1.000).③There was no significant difference in preterm birth rate, cesarean delivery rate, macrosomia percentage, pre-eclampsia rate, percentage of neonates being hospitalized between Group diagnosed during pregnancy A and Group diagnosed before pregnancy (P=0.875, P=0.093, P=0.662, P=1.000, P=0.837). The cesarean delivery rate was lower in Group diagnosed during pregnancy B than that in Group diagnosed before pregnancy (P=0.001). However, there were no significant differences in preterm birth rate, macrosomia percentage, pre-eclampsia rate, percentage of neonates being hospitalized between them (P=0.530, P=0.776, P=1.000, P=0.797). Conclusions: The diagnosis of PGDM is commonly missed before pregnancy. Fasting plasma glucose should be used as screening test to identify PGDM at pre-pregnancy examination or first antenatal care. Using abnormal value of 2-hour glucose after 24 gestational weeks as the only way to diagnose PGDM is not suitable.目的： 分析孕前漏诊（孕期确诊）的孕前糖尿病（PGDM）的临床特点，以及不同的诊断时间点对PGDM孕妇妊娠结局的影响。 方法： 收集2005年1月1日至2015年12月31日在北京大学第一医院分娩、诊断为PGDM的746例孕妇的临床资料。按照PGDM诊断的时间点不同分为孕前诊断组（240例）和孕期诊断组（506例）；并将孕期诊断组中妊娠24周前诊断者定义为孕期诊断A组（100例），孕24周及以后诊断者定义为孕期诊断B组（406例）。分别比较各组孕妇的孕期血糖控制水平和使用胰岛素者的比例，以及早产率、子痫前期发生率、剖宫产率、巨大儿发生率和新生儿转儿科率。 结果： （1）PGDM的漏诊率：所有746例PGDM孕妇中，孕前诊断者仅为32.2%（240/746），PGDM的孕前漏诊率高达67.8%（506/746）。（2）孕期血糖控制水平：①孕前诊断组孕妇的孕期最高糖化血红蛋白（HbA1c）水平明显高于孕期诊断组[分别为（6.6±1.1）%、（6.3±1.0）%，P=0.019]；而两组孕妇的孕期平均HbA1c水平比较，差异无统计学意义（P=0.616）。两组孕妇中使用胰岛素者的比例[90.8%（218/240）、53.8%（272/506）]比较，差异有统计学意义（P<0.01）。②孕期诊断A组孕妇的孕期最高HbA1c水平[（6.9±1.3）%]和平均HbA1c水平[（6.4±0.8）%]均明显高于孕期诊断B组[（6.1±0.8）%、（6.0±0.8）%]，差异均有统计学意义（P均<0.05）。孕期诊断B组孕妇的使用胰岛素者比例[46.1%（187/406）]明显低于孕期诊断A组[85.0%（85/100）]，差异有统计学意义（P<0.01）。③孕期诊断A组孕妇的孕期最高HbA1c水平、平均HbA1c水平分别与孕前诊断组比较，差异均有统计学意义（P=0.020、P=0.037）；使用胰岛素者的比例比较，差异无统计学意义（P=0.128）。孕期诊断B组孕妇的最高HbA1c水平、平均HbA1c水平分别与孕前诊断组比较，差异均有统计学意义（P<0.01、P=0.014）；使用胰岛素者的比例比较，差异有统计学意义（P<0.01）。（3）妊娠结局：①孕前诊断组和孕期诊断组孕妇的剖宫产率[72.5%（174/240）、59.7%（302/506）]比较，差异有统计学意义（P<0.01）。孕前诊断组和孕期诊断组孕妇的早产率、子痫前期发生率、巨大儿发生率、新生儿转儿科率分别比较，差异均无统计学意义（P=0.546、P=1.000、P=0.671、P=0.804）。②孕期诊断A组和孕期诊断B组孕妇的早产率、剖宫产率、巨大儿发生率、子痫前期发生率、新生儿转儿科率分别比较，差异均无统计学意义（P=0.887、P=0.495、P=0.841、P=1.000、P=1.000）。③孕期诊断A组与孕前诊断组的早产率、剖宫产率、巨大儿发生率、子痫前期发生率、新生儿转儿科率分别比较，差异均无统计学意义（P=0.875、P=0.093、P=0.662、P=1.000、P=0.837）；孕期诊断B组孕妇的剖宫产率低于孕前诊断组（P=0.001），而早产率、巨大儿发生率、子痫前期发生率及新生儿转儿科率分别比较，差异均无统计学意义（P=0.530、P=0.776、P=1.000、P=0.797）。 结论： PGDM合并妊娠妇女的孕前漏诊率较高，孕期诊断的PGDM与孕前诊断者的不良妊娠结局发生率相同，故应加强孕前或孕早期的血糖筛查以检出漏诊的PGDM孕妇。孕24周及以后诊断的PGDM孕妇，其诊断依据仅为孕24周及以后口服葡萄糖耐量试验2 h的血糖结果，这部分孕妇与其他时间点诊断的PGDM孕妇的孕期血糖控制水平和使用胰岛素者比例均存在差异，是否应诊断为糖尿病建议产后进一步复查以明确诊断。.