Non-proteinuric pre-eclampsia: a novel risk indicator in women with gestational hypertension

Abstract

Objective: To determine whether outcomes differed for women with pre-eclampsia according to the presence of proteinuria and whether non-proteinuric pre-eclampsia is similar to gestational hypertension.

Design: From 1987 to 2005, at three hospitals in Sydney, Australia, women referred to the obstetric medicine team were recruited. Outcomes for three groups were compared: proteinuric pre-eclampsia, non-proteinuric pre-eclampsia and gestational hypertension.

Results: Women with proteinuric pre-eclampsia were more likely to have severe hypertension (39 versus 30%, P = 0.003), deliver preterm infants (39 versus 30%, P = 0.007) and had a higher perinatal mortality rate (25.2 versus 5.7 per 1000, P = 0.02) than those with non-proteinuric pre-eclampsia, who were more likely to have thrombocytopenia and liver disease. Women with non-proteinuric pre-eclampsia were more likely to have multiple pregnancies (3.9 versus 9.9%, P < 0.001), experience severe hypertension (8.9 versus 29.7%, P < 0.001), and deliver preterm infants (11.3 versus 30.2%, P < 0.001) who were small for gestational age (12.7 versus 20.9%, P < 0.001) than those with gestational hypertension.

Conclusion: This study highlights differences between non-proteinuric pre-eclampsia and gestational hypertension. The subclassification of 'non-proteinuric pre-eclampsia' should be added to existing classification systems to alert clinicians to potential risks.