RESUMEN
Estimates of adherence to antihypertensive treatment in pregnancy are limited; identifying non-adherence could facilitate intervention and optimise blood pressure control. This study aimed to evaluate adherence to antihypertensive treatment amongst pregnant women with chronic hypertension using high-performance liquid chromatography-tandem mass spectrometry instrumentation. Spot urine samples collected from women who were randomised to labetalol or nifedipine were assessed. Samples from 74 women were included; documented prescribing and urine metabolite detection were concordant in 88% (nâ¯=â¯65). Evidence of self-administration of alternative treatment was observed in 8% (nâ¯=â¯6). Measurement of urinary antihypertensive metabolites in pregnancy provides insight into treatment adherence.