Life-threatening ketoacidosis in a pregnant woman with psychotic disorder

Pregnancy is an insulin resistant state. Hyperglycaemia and gestational diabetes mellitus are well-recognised complications even in women without existing metabolic syndrome or obesity. Pregnant women also appear to be more vulnerable to ketoacidosis, particularly after short periods of reduced oral intake in the third trimester, and may present with very severe starvation ketoacidosis, prompting emergent delivery. We present a case of a woman with a background of depression and psychotic episodes. Olanzapine had been commenced after a psychotic episode at 20 weeks' gestation. Gestational diabetes mellitus was diagnosed at 28 weeks, and she was then admitted at 31 weeks with severe euglycaemic ketoacidosis following a short period of vomiting. She underwent caesarean section when the metabolic disturbances did not resolve with medical treatment. We believe atypical antipsychotic therapy contributed to the profound insulin resistance seen here, and that obstetricians, physicians and psychiatrists must be aware of the risks conferred by these agents in pregnancy.