Microalbuminuria is a predictor of adverse pregnancy outcomes including preeclampsia

•We retrospectively examined antepartum peak uACR level and pregnancy outcomes.•As uACR increased, proportion of women with adverse pregnancy outcomes increased.•High uACR especially macroalbuminuria increased risk of adverse pregnancy outcome.•Adverse pregnancy outcomes included poor maternal and poor fetal outcomes.•Antepartum uACR can be a simple marker to predict adverse pregnancy outcomes.

ObjectivesAbnormal urinary protein loss is a marker associated with a diverse range of renal diseases including preeclampsia. Current measures of urine protein used in the diagnostic criteria for the diagnosis of preeclampsia includes urine protein:creatinine ratio and 24-h urine protein. However very little is known about the value of urine albumin:creatinine ratio (uACR) in pregnancy. In this study we examined the prognostic value of microalbuminuria detected antepartum to predict adverse pregnancy outcomes.DesignThis is a single-centre retrospective analysis of 84 pregnant women over the age of 16 attending a tertiary 'high-risk' pregnancy outpatient clinic between July 2010 and June 2013. Utilising medical records, antepartum peak uACR level and pregnancy maternal and fetal outcomes were recorded.FindingsThe primary outcome was a composite of poor maternal and fetal outcomes including preeclampsia, maternal death, eclampsia, stillbirth, neonatal death, IUGR, premature delivery and placental abruption. As the antepartum peak uACR level (in mg/mmol) increased from normoalbuminuria (uACR < 3.5) to microalbuminuria (uACR 3.5-35) to macroalbuminuria (>35), the percentage of women with the primary composite outcome increased in a stepwise fashion (13.8% to 24.1% to 62.1% respectively, p < 0.001). After adjusting for covariates including history of hypertension, chronic kidney disease and aspirin therapy during pregnancy, micro- and macroalbuminuria remained significant predictors of the primary outcome.ConclusionsWe have shown that antepartum peak uACR is a useful simple marker to help predict adverse maternal and fetal outcomes. Further studies are required to utilise uACR as a prognostic tool in pregnancy before it can be applied in clinical practice.