A new study found that, within two weeks of giving birth, new mothers had levels of tetrahydrocannabinol (THC) of 5.5 nanograms per milliliter (ng/mL) in their breast milk (above)

The psychoactive ingredient in marijuana can remain in breast milk for up to six weeks after mothers quit using the drug, a new study suggests.

Researchers found levels of tetrahydrocannabinol (THC) were as high as 5.5 nanograms per milliliter (ng/mL) two weeks after women gave birth.

This is higher than the blood THC level of five ng/mL or higher needed to charge drivers with a DUI (driving under the influence), in some states. 

By six weeks post-delivery, the THC levels in breast milk had dropped to about two ng/mL, low but still detectable.The team, from the University of Colorado School of Medicine, says its findings support recommendations from several groups, including the American Academy of Pediatrics, the Academy of Breastfeeding Medicine and the American College of Obstetricians and Gynecologists to abstain from pot use during pregnancy and while breastfeeding.  

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Psychoactive ingredient in marijuana can stay in breast milk for six WEEKS after giving birth — Daily Mail Online

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