Marijuana and breastfeeding, not to mention marijuana and pregnancy, are complex issues that many people, even those who aren't parents or pregnant, have feelings about.
While some moms say smoking the drug helps them unwind and cope with the daily stresses of being a parent, health experts advise it's not safe to use weed while breastfeeding, and that it should be avoided while pregnant.
And according to a recent small study, inhaled marijuana does show up in breast milk, but the consequences of small amounts of the drug on baby aren't so clear.
The study, which was published April 6 in the journal Obstetrics and Gynecology, concluded that mothers should not smoke marijuana while breastfeeding because it's not known what amounts are safe.
"There's concern for the developing brain exposed to THC [the active component in marijuana]," noted study co-author Dr. Teresa Baker, co-director of the Infant Risk Center at Texas Tech University School of Medicine.
"This study is just a start to see if marijuana transferred into breast milk. Levels in milk were quite low," said senior study author Thomas Hale, director of the Infant Risk Center at Texas Tech.
Study authors also noted that they didn't know if the levels of the drug in breast milk would increase the more a woman smokes.
For their research, study authors enlisted eight mothers from Denver, Colorado (where recreational marijuana is legal), who smoke pot to varying degrees, from infrequently to occasionally. The moms were between two and five months post-delivery, and all were breastfeeding their babies.
These women had to smoke a certain strain of pot from a specific marijuana dispensary, and were asked to stop smoking it for 24 hours before they took a breast milk test. They collected samples of their breast milk 20 minutes, and one, two, and four hours after smoking the pot.
The researchers found that about 2.5 per cent of the amount of pot the moms smoked was found in their breast milk.
Marijuana can affect baby's development
According to Dr. Ronald Marino, chief of the division of general pediatrics at NYU Winthrop Hospital, who reviewed the study's findings, it's only natural that small amounts of the marijuana the moms smoked were found in their breast milk.
"Most things do get into breast milk, and we need to understand this more because we don't know if there's a safe exposure level for babies. But it's probably better not to be exposed," Marino said, according to HealthDay.
"Your baby's brain is developing so much in the first year of life, you want to give them every chance to have high function. Try to stay as pure as you can when breast-feeding — [avoiding] marijuana, alcohol or even herbal remedies," he added.
Toronto's Hospital for Sick Children also advises nursing mothers to abstain from using marijuana.
"Despite abundant recreational use of cannabinoids by women of reproductive age, very little is known about marijuana use and lactation," the hospital's website notes.
"With chronic use, THC can accumulate in human breast milk to high concentrations. Because a baby's brain is still forming, THC could theoretically affect brain development. It is also important to avoid environmental exposure to maternal marijuana smoke."
Sick Kids' website also mentions a 1990 study that suggested that babies who were exposed to THC through breast milk in their first month of life could be at risk of decreased motor development at one year old, but also noted that no studies have "adequately addressed" the long-term effects. The site also notes that other reported observations of babies who were exposed to THC through breast milk included lethargy, less frequent feeding, and shorter feeding times.
But some say small amounts of THC might not harm baby
However, some experts argue that occasional marijuana use while breastfeeding probably won't hurt baby.
"If a mother is using marijuana occasionally, and is capable of taking good care of the baby, there is no reason to advise formula," noted Dr. Jack Newman, a Canadian pediatrician and breastfeeding expert, in his book Dr. Jack Newman's Guide to Breastfeeding. "There is no evidence that the small amounts present in the milk will harm the baby."
On his website, however, Newman does note that a mother's impairment could have harmful effects.
"That is, if the mother is so impaired that she cannot make a good judgment about what her baby needs, that is potentially dangerous for the baby," he wrote.
Impairment is an issue
Mothers who do smoke pot frequently run the risk of being impaired around their child, which can put their child at risk. A 2006 report noted that mothers who smoke pot can risk falling into a deep sleep, thus being unable to care for her baby's needs.
"Just like we don't want people using marijuana and getting behind the wheel of a car, we don't want people using marijuana and trying to parent as well. Your young children need you to be at your mental best, so doing anything that impairs your judgement is not going to be in the best interest of your child," Dr. Michael Dickinson, the president of the Canadian Paediatric Society, told HuffPost Canada in December.
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