Poster 21: Hypoglycaemia on oral glucose tolerance test in pregnancy - is it significant?

Background: Hypoglycaemia during OGTT has been linked with poor pregnancy outcome but results are conflicting.

Method: 75-grams 2-hour OGTT from 2017-2018 of 159 pregnant women were analysed. Women were divided into following groups: normoglycemia (Fasting Blood Glucose 4-5.5 mmol/L and 2-hour OGTT 4-7.7 mmol/L), GDM (FBG ≥ 5.6 mmol/litre or 2-hour OGTT ≥ 7.8 mmol/L), hypoglycaemia (2 hr-OGTT 3-3.9 mmol/L) and clinically significant hypoglycaemia CSH (2 hr-OGTT <3 mmol/L). Endpoints were Maternal BMI, foetal body weight (FBW), mode of delivery and admission to Neonatal Intensive Care Unit (NICU).

Results: Maternal BMI was significantly lower in the hypoglycaemia group (p=0.04) but not in those with CSH (p=0.89). FBW was non-significantly higher in those with CSH (p=0.69).

Mode of delivery was not significantly different between normoglycemia and the 2 hypoglycaemia groups (p=0.74 for hypoglycaemia and p=0.82 for CSH). The GDM group was significantly more likely to require Emergency C-section (p=0.03).

Neonates born to the hypoglycaemia group were more likely to require NICU admission but this was non-significant (p=0.3). None of the neonates born to the CSH group required admission to NICU (n=16).

Discussion: Neonates born to mothers who had hypoglycaemia on 2-hour OGTT were more likely to require admission to neonatal ICU; however, this finding was statistically non-significant. Furthermore, their mode of delivery was non-significantly different to the normoglycemic group. Currently there is insufficient evidence to advocate intense monitoring or treatment in pregnant women who develop hypoglycaemia on oral glucose tolerance test (OGTT).