National guidelines for antenatal testing

It’s time to adopt a cost-effective approach

Hypertensive disorders in pregnancy, and particularly pre-eclampsia, remain major causes of maternal and perinatal mortality,1,2 accounting for 15% of maternal deaths and 4% of perinatal deaths. Therefore, a key aim of modern antenatal care is the timely detection and management of pre-eclampsia.1,2 A traditional belief is that this is best achieved by regular, and increasingly frequent, antenatal visits, allowing for both blood pressure measurement and dipstick urinalysis to detect new-onset proteinuria. This strategy underpins the schedule of antenatal care that is still most commonly followed in Australia; namely, monthly visits until 28 weeks of pregnancy, fortnightly visits until 36 weeks and weekly visits thereafter.3 However, it has been apparent for some time that the frequency of visits could be safely reduced without adversely affecting outcomes,4 a notion now confirmed by randomised controlled trials both in the developed and developing world.5 Similarly, it has long been recognised that dipstick urinalysis performs poorly in the detection of proteinuria,1 requiring confirmation by either a formal 24-hour urine collection or a spot urine protein/creatinine ratio.2 However, the accuracy of a dipstick reading is significantly improved if it is read with an automated device rather than visually,6 offering the possibility that routine automated testing for proteinuria may have a place in the detection of pre-eclampsia.