Introduction: Glycaemic targets recommended to women with gestational diabetes aim to reduce the risk of adverse outcomes, but optimal targets are uncertain and adherence is variable. We assessed the effect of adherence to tight or less tight glycaemic targets on maternal and infant health.
Methods: Women from the TARGET1 trial were eligible if fasting and postprandial capillary blood glucose readings were available at 36 weeks’ gestation. Outcomes were analysed for ≥80% and ≥50% adherence to allocated targets. Data are presented for comparison between target groups in participants with ≥80% adherence.
Results: Of 356 women, 33.4% achieved ≥80% adherence and 64.3% ≥50% adherence to both fasting and postprandial targets, with fewer women adhering to fasting than postprandial targets. Women who adhered to tight glycaemic targets were less likely than women who adhered to less tight targets to have a large for gestational age infant (fasting: 1.6% versus 12.8%, p=0.007) but more likely to birth by caesarean section (postprandial: 47.8% versus 38.2%, relative risk (RR) 1.64, 95% CI 1.01-2.68, p=0.05), and their infants had higher birth weight z-scores (postprandial: 0.3 versus 0.1, mean difference (MD) 0.44, 95% CI 0.14-0.75, p=0.005) and head circumference z-scores (postprandial: 0.5 versus 0.3, MD 0.43, 95% CI 0.08-0.78, p=0.02).
Conclusions: Few women adhered to their recommended glycaemic targets, especially fasting targets. Women who adhered to tight targets were less likely to have a large for gestational age infant, although more likely to give birth by caesarean section than women who adhered to less tight targets.