Does Cannabis Use Affect Breast Milk? - Chromatography Explores

Pregnancy and childbirth are amongst the most natural processes humans encounter. Evolution drives us to reproduce and keep the species going, making babies is our main purpose. To help produce fit and healthy mothers and infants, it is recommended that a healthy lifestyle is followed, before, during and after the pregnancy.

Food, drink, and drugs can all effect both the mother and baby before, during and after pregnancy. In a recent study, researchers found that tetrahydrocannabinol (THC) which is the psychoactive component in marijuana can remain in breast milk for up to six weeks potentially affecting an infant's development. This is the first study looking at THC in breastmilk for almost forty years and was carried out due to the increased use of marijuana in society, especially since the legalization of marijuana in some parts of the US.

Increasing marijuana use in society

The team of researchers from the University of Colorado and University of Utah studied women who had a history of prenatal marijuana use and delivered their infants at hospital in Colorado. To women had to have a positive marijuana test on admission and an intention to breastfeed along with a willingness to have blood, urine and milk samples taken after delivery. They also had to abstain from marijuana use for six weeks after delivery.

Part of the reason for the study - Persistence of Δ-9-Tetrahydrocannabinol in Human Breast Milk – published in JAMA Pediatrics is because of the increased use of marijuana in society and that little is known about THC and how long it persists in breastmilk. Erica Wymore, lead investigator on the study said in a Children’s Hospital Colorado press release

“With this study, we aimed to better understand this question by determining the amount and duration of THC excretion in breast milk among women with known prenatal marijuana use."

THC remains in the milk

From a total of almost 400 women who were initially screened, 25 were enrolled in the study, but only seven were able to meet the criteria of abstaining from marijuana for the duration of the study. The participants gave breastmilk and plasma samples to the research team several times a week. These samples were then analysed using high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) for THC concentration. Analysis using liquid chromatography is discussed in the article, Faster Time to Results for Ultra-Performance Liquid Chromatographic Separations of Metal-Sensitive Analytes.

It was found that all 25 participants had THC in their breastmilk throughout the study. The seven women who didn’t use marijuana during the study still had a significant amount of THC in their breastmilk at the end of six weeks. In the press release, Maya Bunik professor of paediatrics at the CU School of Medicine and medical director of the Children’s Hospital Colorado, said

“To limit the unknown THC effects on fetal brain development and promote safe breastfeeding, it is critical to emphasize marijuana abstention both early in pregnancy and postpartum.”