Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sunnybrook Health Sciences Center, University of Toronto, Toronto, Ontario, Canada.
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
Am J Obstet Gynecol. 2016 May;214(5):653.e1-8. doi: 10.1016/j.ajog.2015.11.006. Epub 2015 Nov 17.
Women with twin pregnancies are at increased risk for fetal growth restriction, which might be attributed to the limited maternal resources that are being shared by >1 fetus. Based on that, it may be hypothesized that the fetal effects of gestational diabetes mellitus (GDM) with respect to accelerated fetal growth may be less pronounced in twin gestations or alternatively may even have a beneficial role in decreasing the risk of fetal growth restriction in these pregnancies. However, available data are conflicting and are limited by the fact that many of the complications associated with GDM are less relevant for twin gestations, and that all women with GDM included in previous studies were monitored and treated to control maternal blood glucose levels.
We sought to assess the impact of GDM and milder degrees of glucose intolerance on fetal growth and pregnancy outcome in twin pregnancies.
This was a retrospective cohort study of all women with twin pregnancies who underwent screening for GDM in a single tertiary referral center from October 2003 through December 2014. The diagnosis of GDM during the study period was based on the 2008 Canadian Diabetes Association (CDA) guidelines, which involve universal screening with a 50-g glucose challenge test (GCT) followed by a diagnostic 2-hour 75-g oral glucose tolerance test (OGTT). Fetal growth and pregnancy outcome were compared among 4 groups of women with increasing degree of glucose intolerance: (1) GCT-NEGATIVE, negative 50-g GCT; (2) OGTT-NEGATIVE, positive 50-g GCT followed by a negative 75-g OGTT; (3) GDM-IADPSG, positive 50-g GCT followed by a positive 75-g OGTT according to the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria but not the 2008 CDA criteria-because these women were not considered to have GDM during the study period they were not subjected to any form of treatment; and (4) GDM-CDA, positive 50-g GCT followed by a positive 75-g OGTT according to the 2008 CDA criteria.
Overall 1393 women were eligible for the study: 1021 (73.3%) in the GCT-NEGATIVE group, 184 (13.2%) in the OGTT-NEGATIVE group, 99 (7.1%) in the GDM-IADPSG group, and 89 (6.4%) in the GDM-CDA group. There was a continuous relationship between the degree of glucose intolerance and fetal growth as reflected by a right shift of the distribution curve of birthweight percentiles and a greater likelihood of high birthweight percentile: OGTT-NEGATIVE = odds ratio (OR), 1.5; 95% confidence interval (CI), 1.07-2.2; GDM-IADPSG = OR, 1.7; 95% CI, 1.1-2.6; and GDM-CDA = OR, 1.9, 95% CI, 1.3-3.1 (using the GCT-NEGATIVE group as reference). Fetuses of women with glucose intolerance were more likely to experience asymmetric growth as reflected by an elevated abdominal circumference to head circumference ratio.
GDM and milder degrees of glucose intolerance in twin pregnancies are associated with an increased risk of asymmetric overgrowth in a manner that is related to the degree of glucose intolerance.
怀有双胞胎的女性胎儿生长受限的风险增加，这可能归因于 >1 个胎儿所共享的有限的母体资源。基于此，可能假设妊娠期糖尿病（GDM）对胎儿生长的加速作用在双胎妊娠中可能不那么明显，或者甚至可能在降低这些妊娠中胎儿生长受限的风险方面发挥有益作用。然而，现有数据存在冲突，并且受到以下事实的限制：与 GDM 相关的许多并发症对双胎妊娠的相关性较小，并且之前研究中纳入的所有 GDM 女性都接受了监测和治疗以控制母体血糖水平。
我们旨在评估 GDM 和较轻程度的葡萄糖耐量异常对双胎妊娠中胎儿生长和妊娠结局的影响。
这是一项回顾性队列研究，纳入了 2003 年 10 月至 2014 年 12 月在一家三级转诊中心接受 GDM 筛查的所有双胎妊娠女性。研究期间 GDM 的诊断基于加拿大糖尿病协会（CDA）2008 年指南，该指南涉及使用 50 克葡萄糖挑战试验（GCT）进行普遍筛查，随后进行诊断性 2 小时 75 克口服葡萄糖耐量试验（OGTT）。在 4 组葡萄糖耐量异常程度逐渐增加的女性中比较了胎儿生长和妊娠结局：（1）GCT-阴性，50 克 GCT 为阴性；（2）OGTT-阴性，50 克 GCT 阳性，随后 75 克 OGTT 为阴性；（3）GDM-IADPSG，根据国际妊娠糖尿病研究组（IADPSG）标准，50 克 GCT 阳性，随后 75 克 OGTT 阳性，但不符合 2008 年 CDA 标准-因为这些女性在研究期间未被认为患有 GDM，因此未接受任何形式的治疗；和（4）GDM-CDA，根据 2008 年 CDA 标准，50 克 GCT 阳性，随后 75 克 OGTT 阳性。
共有 1393 名女性符合研究条件：1021 名（73.3%）在 GCT-阴性组，184 名（13.2%）在 OGTT-阴性组，99 名（7.1%）在 GDM-IADPSG 组，89 名（6.4%）在 GDM-CDA 组。随着出生体重百分位数分布曲线的右移和高出生体重百分位数的可能性增加，葡萄糖耐量异常的程度与胎儿生长之间存在连续关系：OGTT-阴性=比值比（OR），1.5；95%置信区间（CI），1.07-2.2；GDM-IADPSG=OR，1.7；95%CI，1.1-2.6；和 GDM-CDA=OR，1.9，95%CI，1.3-3.1（以 GCT-阴性组为参考）。葡萄糖耐量异常女性的胎儿更有可能出现不对称生长，表现为腹围与头围比升高。
双胎妊娠中 GDM 和较轻程度的葡萄糖耐量异常与不对称过度生长的风险增加相关，这种关系与葡萄糖耐量异常的程度有关。
