How high is too high in cutoff levels from 50-g glucose challenge test

Diagnosis of gestational diabetes: Are five rounds of blood sampling necessary?

We aimed to determine the upper and lower cutoff values to simplify the diagnosis of gestational diabetes mellitus (GDM). We investigated the 50-g oral glucose tolerance test (OGTT) results from 1441 pregnancies and identified 423 gravidas who underwent the 100-g OGTT from 2011 to 2019. We collected the results of 50- and 100-g OGTTs. Moreover, we obtained the sum of the 50-g OGTT and 0-hour values, and the sum of those levels and 1-hour values. We determined the upper cutoff at 50-g OGTT, 0-, 1-hour, sum of 50-g OGTT and 0-hour results, and sum of those levels and 1-hour results for the confirmation of GDM. Also, we determined the lower cutoff at these tests for the exclusion of GDM. The upper cutoffs in 50-g OGTT, 0-, 1-hour, the sum of 50-g OGTT and 0-hour were 222, 115, 212, and 315 mg/dL, respectively. The lower cutoffs in 50-g OGTT, 0-, 1-hour, the sum of 50-g OGTT and 0-hour were 131, 65, 151, and 208 mg/dL, respectively. In addition, we discovered that the upper and lower cutoffs in the sum of 50-g OGTT, 0- and 1-hour values were >516 and <373 mg/dL, respectively. We implemented these cutoffs to our study group at 50-g OGTT and 0-, 1-hour of 100-g OGTT. It could omit 2- and 3-hour sampling in 216 gravidas (51.1%). Our approach was able to simplify GDM diagnostic steps in half of our study group.

The trends and risk factors to predict adverse outcomes in gestational diabetes mellitus: a 10-year experience from 2006 to 2015 in a single tertiary center

Objective

To investigate the change of maternal characteristics, delivery and neonatal outcomes in gestational diabetes mellitus (GDM) over recent 10 years and to identify the risk factors associated with adverse outcome.

Methods

Consecutive GDM patients (n=947) delivered in our institution were included. Research period was arbitrarily divided into 2 periods (period 1: from 2006 to 2010, period 2: from 2011 to 2015). Multiple pregnancies or preexisting diabetes were excluded. Maternal baseline characteristics, delivery and neonatal outcomes were reviewed. Fetal biometric findings by prenatal ultrasonography were collected. Adverse pregnancy outcome (APO) was defined by the presence of one of the followings; shoulder dystocia, neonatal macrosomia (>4 kg), neonatal hypoglycemia (<35 mg/dL), respiratory distress syndrome (RDS), and admission to the neonatal intensive care unit (NICU) in term pregnancy.

Results

Period 2 was associated with older maternal age (34 vs. 33, P<0.001) and higher proportion of GDM A2 compared to period 1 (30.9% vs. 23.0%, P=0.009). By univariate analysis, APO was associated with increased body mass index (BMI) at pre-pregnancy (23.4 kg/m² vs. 21.8 kg/m², P=0.001) or delivery (27.9 kg/m² vs. 25.8 kg/m², P<0.001), higher HbA1c at diagnosis (5.6% vs. 5.3%, P<0.001) or delivery (5.8% vs. 5.5%, P=0.044), and larger fetal biometric findings (abdominal circumference [AC] and estimated fetal weight, P=0.029 and P=0.007, respectively). Multivariate analysis showed pre-pregnancy BMI (odds ratio [OR], 1.101; 90% confidence interval [CI], 1.028–1.180) and fetal AC (OR, 1.218; 90% CI, 1.012–1.466) were independently associated with adverse outcomes.

Conclusion

Our study demonstrated the trends and relevant factors associated with the adverse outcomes.