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Date of last update: 8/13/2017.

Forum Name: Urology Topics

Question: Pregnant and positive urine test for alcohol but not drinkin

 chrissyandlee2 - Fri Jul 09, 2010 9:54 am

I got a DUI about two years ago and am now in counseling in order to get my liscense back. During the counseling sessions, they have me give a urine drop twice a week. I have been positive for alcohol every single time. Below the positive line, it states that their are traces of yeast so the result may be a false positive. However, I am also testing positive for ethyl glurcuronide in the 80 hour urinalysis. I am 8 months pregnant and have not been drinking at all. How is the test coming back positive?
 Dr.M.Aroon kamath - Mon Jul 12, 2010 10:32 pm

User avatar Hi,
A small proportion individuals from time to time, since long have continued to voice their misgivings about the urinary alcohol testing, alleging that the postitivity in their cases was an error(false positives)- the so-called "innocent positives".

The standard law enforcement practice is to take two samples, at 30-minute intervals, the latter sample preferably after emptying the urinary bladder.

Three laboratory methods have been in common use:
- chemical tests;
- biochemical tests; and
- gas chromatography.

Gas chromatography is perhaps the most widely used because it can distinguish alcohol from substances such as ketones and aldehydes (a problem that exists with diabetics, starvation, anorexia, and a host of other situations)

EtG (ethyl glucuronide) test was introduced around 2004
Etg may be detected in urine up to 80 hours(about 4 times longer than alcohol). This seemingly wider window of detection made EtG an instant favourite for urinary alcohol testing. Concerns about this test also surfaced soon thereafter.

Some of the factors that may affect the accuracy of this test are,
- Exposure of the urine samples to air: not only contributes to putrefaction of alcohol samples but generates oxidizable organic substances that may cause false positivity.
- yeast or other bacterial infections: Yeast and bacteria produce ethanol as a biproduct while acting on sugars, which may result in false positivities.
- laboratary- related factors: such as the quality and shelf life of the reagents,method of sterilization of the related instruments etc).

I hope this information is helpful to you.
Best wishes!

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