Screening for Gestational Diabetes Mellitus in Early Pregnancy: What Is the Evidence?

Abstract

The incidence of gestational diabetes mellitus (GDM) is increasing worldwide. This has a significant effect on the health of the mother and offspring. There is no doubt that screening for GDM between 24 and 28 weeks is important to reduce the risk of adverse pregnancy outcomes. However, there is no consensus about diagnosis and treatment of GDM in early pregnancy. In this narrative review on the current evidence on screening for GDM in early pregnancy, we included 37 cohort studies and eight randomized controlled trials (RCTs). Observational studies have shown that a high proportion (15–70%) of women with GDM can be detected early in pregnancy depending on the setting, criteria used and screening strategy. Data from observational studies on the potential benefit of screening and treatment of GDM in early pregnancy show conflicting results. In addition, there is substantial heterogeneity in age and BMI across the different study populations. Smaller RCTs could not show benefit but several large RCTs are ongoing. RCTs are also necessary to determine the appropriate cut-off for HbA1c in pregnancy as there is limited evidence showing that an HbA1c ≥6.5% has a low sensitivity to detect overt diabetes in early pregnancy.

Prevalence and Risk Factors of Gestational Diabetes Mellitus in Bangladesh: Findings from Demographic Health Survey 2017–2018

“…However, because of the growing number of type 2 diabetes among women of reproductive age, screening women early in their pregnancy for abnormal blood glucose level is likely to improve pregnancy outcomes through appropriate dietary advice and pharmacological interventions [ 9 , 12 ]. Although the evidence regarding the benefits of early screening and treatment of GDM on pregnancy outcomes remains inconclusive, including evidence from small, randomised controlled trials, further large studies have been recommended among different population groups, including those from low- and middle-income countries and in low-risk populations [ 32 ]. Our findings add to calls for such a study to target GDM interventions in different contexts.…”

Prediction of gestational diabetes mellitus using early oral glucose tolerance test

“…However, A narrative review published y Raets et al, indicate that mothers with early GDM are at more risk of adverse pregnancy outcomes. It further highlights that some pregnant women have hyperglycemia under the range of classification as diabetes at booking visit who will later be diagnosed with GDM at 24-28 weeks[6]. According to our study the individual values of fasting, one-hour and two-hour blood glucose individually does not predict the risk of future GDM with great accuracy.…”

Observations of the Effects of Maternal Fasting Plasma Glucose Changes in Early Pregnancy on Fetal Growth Profiles and Birth Outcomes

“…In this regard, the IADSPG recommended that early FPG ≥5.1 mmol/L should be considered to define early GDM and supported immediate intervention of maternal glycemic control. To date, whether women with early-onset GDM could benefit from surveillance and management remains controversial due to lack of evidence from large randomized controlled trials (RCTs) ( 13 ), and they only observed the outcomes at birth and ignored the process of intrauterine growth. This finding in our study provides potential clinical implications to encourage future large-scale RCTs to pay extra attention to the fetal growth pattern during the management process.…”