Factors associated with higher risk of small‐for‐gestational‐age infants in women treated for gestational diabetes

Abstract

BackgroundPreviously, management of gestational diabetes (GDM) has focused largely on glycaemic control, with a view to reduce the occurrence of large‐for‐gestational‐age (LGA) infants. However, tight glycaemic control in GDM is associated with a higher incidence of small‐for‐gestational‐age (SGA) infants, which has been linked to higher rates of adverse outcomes.AimThe aim was to characterise risk factors associated with having an SGA infant in women being treated for GDM.MethodsThis was a retrospective observational cohort study of 308 women with GDM. Women were split into groups based on their infant's size at delivery (SGA, appropriate‐for‐gestational‐age (AGA) or LGA). Literature review and expert opinion helped to determine several predictors of women with GDM delivering an SGA infant, and statistical analysis was used to produce odds ratios (OR) for these predictors.ResultsThe sample included primiparous women with a mean pre‐pregnancy body mass index (BMI) of 25.72 (standard deviation: 5.75). Metabolic risk factors associated with delivering an SGA infant included a lower pre‐pregnancy BMI (adjusted OR 1.13, P = 0.04, 95% confidence interval (CI): 1.01–1.26), a lower fasting blood glucose level (BGL) (adjusted OR: 3.21, P = 0.01, 95% CI: 1.30–7.93) and growth that was high risk for SGA at baseline ultrasound scan (USS) (adjusted OR: 7.43, P < 0.001, 95% CI: 2.93–18.79).ConclusionsThe combined clinical picture of lower pre‐pregnancy BMI, fasting BGL and baseline USS growth measurements may indicate a need for less aggressive glucose management in women with GDM to prevent SGA infants.

Dose-Response Relationship between Gestational Weight Gain and Neonatal Birthweight in Chinese Women with Excess Weight/Obesity and Gestational Diabetes Mellitus

“…More recently, Huang et al also showed that women with GDM who had GWG below the guidelines did not increase the risk of SGA, although SGA babies had more adverse outcomes in newborns born to mothers with GDM [ 43 ]. Additionally, Drever et al’s analysis of a clinical picture with decreased preconception BMI, fasting blood glucose levels, and baseline USS growth measurements alone may indicate that women with GDM only need minimal active glucose management to prevent SGA [ 44 ]. Furthermore, Monteiro et al found that only women with normal and low pre-pregnancy BMI and a GWG below 3 kg had a higher risk of SGA [ 45 ].…”

Multigenerational diabetes mellitus

“…More recently, predictors of infant adiposity are thought to be closer related to maternal body mass index (BMI) and lipid, rather than glycaemic levels ( 9 , 16 ), which are the current focus of GDM management protocols. SGA is linked to genetic factors and pre-eclampsia, however is also observed in strictly controlled GDM ( 15 ), particularly in women with lower pre-pregnancy BMI and lower fasting blood glucose levels ( 17 ). For this population, debate remains as to whether less stringent blood glucose targets should apply.…”

Receiving the baton

“…Diagnostic cutoff values for GDM and glycaemic targets and the treatment required to achieve them remain controversial with opponents of stricter cutoffs and targets suggesting they impose substantial resource burdens without important clinical benefits or that treatment according to strict criteria may lead to an increase in small‐for‐gestational‐age (SGA) neonates. Drever et al evaluated risk factors for SGA in women treated for GDM, finding that those with lower body mass index (BMI), lower fasting glucose levels, and smaller fetuses at baseline growth assessment were at greater risk of SGA 8 . These findings suggest a need to tailor GDM management according to individual patient factors.…”