ABSTRACT
OBJECTIVE: To determine whether screening for gestational diabetes mellitus (GDM) in the third trimester and managing those who are screen positive on a diabetes pathway affects obstetric and neonatal outcomes. DESIGN: Retrospective study of prospectively collected data. SETTING: London Teaching Hospital. POPULATION OR SAMPLE: A total of 14 366 women delivering between 1 January 2018 and 31 December 2020. METHODS: Retrospective chart analysis. MAIN OUTCOME MEASURES: Diagnosis of late-onset GDM, obstetric and neonatal outcomes. RESULTS: Five hundred and thirty-one women were tested by home glucose monitoring for late-onset GDM from 33 weeks of gestation. In all, 244 were diagnosed as having GDM (group 1) and managed accordingly, and 287 (group 2) were returned to normal care. A total of 1415 women had GDM diagnosed by oral glucose tolerance test before 33 weeks of gestation (group 3). Of the women in group 2, 49.5% had a spontaneous onset of labour compared with only 25.8% and 27% in groups 1 and 3. However, women in group 2 were significantly more likely to have a macrosomic baby (≥4000 g, 25.4%) than groups 1 (16.0%) or 3 (7.2%), and their babies were more likely to be admitted to special care (5.2% versus 2% in group 1). Macrosomic babies were associated with significantly higher rates of shoulder dystocia, third- and fourth-degree tears and postpartum haemorrhage. CONCLUSIONS: Apparent late-onset GDM affects a significant proportion of women, and targeted intervention was associated with better obstetric and neonatal outcomes. These results suggest that all pregnancies with risk factors for late-onset GDM might benefit from active GDM management irrespective of specific glucose thresholds. TWEETABLE ABSTRACT: Women with risk factors for GDM in the third trimester, and their babies, would probably benefit from active management of their blood sugars irrespective of threshold values.
