Naylor C D, Sermer M, Chen E, Sykora K
Department of Medicine, University of Toronto, Ontario, Canada.
JAMA. 1996 Apr 17;275(15):1165-70.
To examine the relationship between birth weight and mode of delivery among women with untreated borderline gestational diabetes mellitus (GDM), treated overt GDM, and normoglycemia.
Prospective cohort study.
Three Toronto, Ontario teaching hospitals.
A total of 3778 volunteers aged 24 years or older.
Subjects underwent a 3-hour long, 100-g oral glucose tolerance test at 28 weeks' gestation, regardless of screening test results. Usual care was provided to 143 women who met the National Diabetes Data Group criteria for GDM. Physicians were blinded to glucose tolerance test results for all others, including 115 untreated women with borderline GDM by the broader criteria of Carpenter and Coustan.
Crude and adjusted rates of cesarean delivery and neonatal macrosomia (birth weight >4000 g).
Compared with normoglycemic controls, the untreated borderline GDM group had increased rates of macrosomia (28.7% vs 13.7%, P<.001) and cesarean delivery (29.6% vs 20.2%, P=.02). Cesarean delivery in this subgroup was associated with macrosomia (45.5% vs 23.5%, P=.03). Usual care of known GDM normalized birth weights, but the cesarean delivery rate was about 33% whether macrosomia was present or absent. A clearly increased risk of cesarean delivery among treated patients compared with normoglycemic controls persisted after adjustment for multiple maternal risk factors (adjusted odds ratio, 2.1; 95% confidence interval, 1.3 to 3.6).
Infant macrosomia was a mediating factor in high cesarean delivery rates for women with untreated borderline GDM. While detection and treatment of GDM normalized birth weights, rates of cesarean delivery remained inexplicably high. Recognition of GDM may lead to a lower threshold for surgical delivery that mitigates the potential benefits of treatment.
研究未经治疗的边缘性妊娠期糖尿病（GDM）、已治疗的显性GDM及血糖正常的女性的出生体重与分娩方式之间的关系。
前瞻性队列研究。
安大略省多伦多市的三家教学医院。
共有3778名年龄在24岁及以上的志愿者。
无论筛查结果如何，受试者在妊娠28周时接受为期3小时的100克口服葡萄糖耐量试验。对143名符合美国国家糖尿病数据组GDM标准的女性提供常规护理。对包括115名根据Carpenter和Coustan更宽泛标准诊断为未经治疗的边缘性GDM的女性在内的所有其他受试者，医生对其葡萄糖耐量试验结果不知情。
剖宫产和新生儿巨大儿（出生体重>4000克）的粗率和校正率。
与血糖正常的对照组相比，未经治疗的边缘性GDM组巨大儿发生率（28.7%对13.7%，P<0.001）和剖宫产率（29.6%对20.2%，P=0.02）均升高。该亚组中的剖宫产与巨大儿相关（45.5%对23.5%，P=0.03）。已知GDM的常规护理使出生体重正常化，但无论有无巨大儿，剖宫产率均约为33%。在对多个母亲风险因素进行校正后，与血糖正常的对照组相比，已治疗患者的剖宫产风险明显增加仍然存在（校正比值比，2.1；95%置信区间，1.3至3.6）。
婴儿巨大儿是未经治疗的边缘性GDM女性剖宫产率高的一个中介因素。虽然GDM的检测和治疗使出生体重正常化，但剖宫产率仍然高得令人费解。对GDM的认识可能导致手术分娩阈值降低，从而削弱治疗的潜在益处。
