Prevalence of maternal urinary ketones in pregnancy in overweight and obese women.

Background: Ketonuria may be associated with adverse fetal outcomes. This study aimed to determine the prevalence of ketonuria at three time points in pregnancy and to assess whether ketonuria correlates with a clinical indication for performing a urine test.

Methods: Women had fasting urinary ketone levels measured at 16 and 28 weeks gestation and random ketone levels measured close to 36 weeks gestation. All ketone levels in the third trimester were recorded along with the clinical indication for the test.

Results: One hundred and eighty-seven women were included in the study. Twenty-two per cent of women had ketonuria at either 16 or 28 weeks gestation and 8% at 36 weeks gestation. Ketonuria was significantly more likely if a test was performed for a clinical indication ( p  = 0.0002).

Conclusion: Ketonuria in pregnancy is common affecting at least one in five women. Ketonuria is more common in women who have a clinical indication for performing a urine test.