Background
Some women with diabetes in pregnancy express and store colostrum in the antenatal period for the purposes of preventing and treating neonatal hypoglycaemia.

Aims
Our primary aim was to compare rates of neonatal hypoglycaemia in babies born to mothers who express and store antenatal colostrum to babies born to mothers who do not.

Materials and methods
Retrospective cohort study involving 357 women with diabetes in pregnancy, who had live, singleton births delivered after 36 weeks gestation, in a regional hospital in North Queensland (2014–2015). Multivariable binary logistic regression modelling identified independent characteristics associated with primary outcomes.

Results
Eighty women (23%) expressed antenatal colostrum and 223 (62%) did not. One hundred and thirty‐one babies (37%) were diagnosed with hypoglycaemia. Aboriginal and Torres Strait Islander women were less likely to express than Caucasian women (odds ratio (OR) 0.10, 95% confidence interval (CI) 0.01–0.77). There were no significant differences in the rates of hypoglycaemia, or median blood glucose levels in babies born to mothers who expressed antenatal colostrum compared to babies born to mothers who did not express. Babies born to mothers who expressed were significantly less likely to receive formula in hospital compared to babies born to mothers who did not (OR 0.12, 95% CI 0.05–0.32).

Conclusions
We found no independent association of expressing antenatal colostrum on rates of neonatal hypoglycaemia or median blood glucose levels. Expressing antenatal colostrum may have some benefits to the newborn such as reduced formula consumption in hospital. Further research into other methods of reducing neonatal hypoglycaemia appears warranted.