Drug screening during pregnancy: Urine dip cups measure up

Substance use during pregnancy is a major medical and public health concern. Determination of the most appropriate screening protocol remains a clinical conundrum. Interviews and/or laboratory drug screens may be costly, inaccurate, and are frequently inadequate to identify patterns of substance use for a given population or geographic area. We compared commercially available urine "dip cup" toxicology screens obtained in the clinic to university hospital drug toxicology results.

267 observed urine samples were collected from pregnant women with known substance use disorders enrolled in a specialized treatment program that included access to buprenorphine medication-assisted treatment. Each urine sample was tested by commercial dip cup with temperature confirmation and then sent to the university hospital laboratory for analyses. The number of substances detected and cost for each screening method were compared.

Uniformly, the dip cup had comparable detection of amphetamines, barbiturates, cocaine, methadone, opiates, and tetrahydrocannabinol to the university hospital laboratory with the exception of benzodiazepines. In addition, the dip cup detected use of buprenorphine (a commonly misused opiate receptor ligand not included in the hospital screen) and was significantly less expensive.

Commercially available urine dip cups are cost-effective, equally comparable to hospital based screening, and provide 'real time' results germane to clinical care and treatment planning.