Is Cannabis sativa Safe in Breastfeeding

I am a breastfeeding mother and i want to know if it is safe to use Cannabis sativa? Is Cannabis sativa safe for nursing mother and child? Does Cannabis sativa extracts into breast milk? Does Cannabis sativa has any long term or short term side effects on infants? Can Cannabis sativa influence milk supply or can Cannabis sativa decrease milk supply in lactating mothers?

Agricultural, textile or industrial hemp is a variety of Cannabis sativa with low content of Delta-9 tetrahydrocannabinol (THC). Although both are the same plant (Sawler 2015), the term “Hemp” is used for the agricultural variety with industrial uses, textiles and foodstuffs leaving the denomination “Cannabis” to the variety that is cultivated for recreational purposes. Agricultural hemp must contain less than 0.2% to 0.3% of THC to be considered legal depending on the country (Avico 1985, Leson 2001,Hemp is used on textile industry for manufacturing of fabrics, paper, insulating elements, motor fuel, paint and cosmetics, among other uses. 

In human food the seeds (cannons), whole, raw or roasted and ground in the form of flour or its oil are used. In 100 grams there are 32 g of protein (all essential amino acids), 49 g of fat (practically all polyunsaturated, linoleic and linolenic acids, ω-3 and ω-6), 5 g of carbohydrates (4 g of fiber), vitamins and minerals with a total of 586 calories.In Chinese medicine it is used on the treatment of constipation (Cheng 2011) It would be advisable to garantee the origin of the seeds and the quality of supplier because there are three possible sources of higher risk with its consumption:1- Confusion at selection of plants with a higher content of THC can lead to positivity on drug testing that would result in poisoning (Fortner 1997, Lehmann 1997, Meier 1997, Alt 1998, Chinello 2016).2- A likely bacterial contamination has led to food poisoning (Willis 2009, Stöcker 2011)3- Hemp is a plant that has been used as a "soil cleaner", because of its high capacity of metal and toxin absorption. Its content in Cadmium, Zinc, Iron and other contaminants may be high (Campbell 2002, Mihoc 2012).

There is no evidence of its effectiveness on preventing and treating cardiovascular disease, diabetes, obesity, overweight and others (Kaul 2008).At latest update no published data were found on its excretion into breastmilk.Provided a reliable source is available, moderate consumption during breastfeeding would pose little or no risk.Hemp is not considered as an essential supplement whenever a healthy balanced diet is followed.

Although published data are limited, it appears that main psychoactive component of cannabis, tetrahydrocannabinol (THC), is excreted into breastmilk in small quantities. The duration of detection of THC in milk has ranged from 6 days to greater than 6 weeks in various studies. Concern has been expressed regarding the possible effects of cannabis on neurotransmitters, nervous system development and endocannabinoid-related functions.[1][2] One long-term study found that daily or near daily use might retard the breastfed infant's motor development, but not growth or intellectual development.[3] This and another study[4] found that occasional maternal cannabis use during breastfeeding did not have any discernable effects on breastfed infants, but the studies were inadequate to rule out all long-term harm. Although cannabis can affect serum prolactin variably, it appears not to adversely affect the duration of lactation. Other factors to consider are the possibility of positive urine tests in breastfed infants, which might have legal implications, and the possibility of other harmful contaminants in street drugs. Health professionals' opinions on the acceptability of breastfeeding by cannabis-using mothers varies considerably.[5][6][7] Cannabis use should be minimized or avoided by nursing mothers because it may impair their judgment and child care abilities. Some evidence indicates that paternal cannabis use increases the risk of sudden infant death syndrome in breastfed infants. Cannabis should not be smoked by anyone in the vicinity of infants because the infants may be exposed by inhaling the smoke. Because breastfeeding can mitigate some of the effects of smoking tobacco and little evidence of serious infant harm has been seen, it appears preferable to encourage mothers who use cannabis to continue breastfeeding and reducing or abstaining from cannabis use while minimizing infant exposure to the smoke.[8][9][10]

Twenty-seven mothers reported smoking marijuana during breastfeeding. Twelve of them smoked once a month or less, 9 smoked weekly, and 6 smoked daily. Six of their infants were compared at 1 year of age to the infants of mothers who did not smoke marijuana during pregnancy or breastfeeding. No differences were found in growth, or on mental and motor development.[4] Sixty-eight infants whose mothers reported smoking marijuana during breastfeeding were compared to 68 matched control infants whose mothers did not smoke marijuana. The duration of breastfeeding varied, but the majority of infants were breastfeed for 3 months and received less than 16 fluid ounces of formula daily. Motor development of the marijuana-exposed infants was slightly reduced in a dose-dependent (i.e., number of reported joints per week) manner at 1 year of age, especially among those who reported smoking marijuana on more than 15 days/month during the first month of lactation. No effect was found on mental development.[3] A small, case-control study found that paternal marijuana smoking postpartum increased the risk of sudden infant death syndrome. In this study, too few nursing mothers smoked marijuana to form any conclusion.[18] A study of women taking buprenorphine for opiate substitution during pregnancy and lactation found that 4 of the women were also using cannabis as evidenced by positive urine screens for THC between 29 and 56 days postpartum. One was also taking unprescribed benzodiazepines. One infant was exclusively breastfed and the other 3 were mostly breastfeeding with partial supplementation. Infants had no apparent drug-related adverse effects and showed satisfactory developmental progress.[19] A 7-month-old previously healthy, unvaccinated, breastfed (extent not stated) boy presented to the ED with increasing lethargy for 6 hours and nonbilious, nonbloody vomiting for 2 hours and a 1-day history of watery diarrhea, cough and congestion. The infant had reportedly fallen 8 inches from a mattress to the floor on the previous evening and breastfed more frequently afterwards. The mother reported that both she and her partner used medical cannabis legally and the infant had a positive urine drug screen for cannabis.[20] Cannabis in breastmilk was a possible contributing factor to the infant's lethargy, but possible direct ingestion could not be ruled out.

Acute one-time marijuana smoking suppresses serum concentrations of luteinizing hormone and prolactin in nonpregnant, nonlactating women.[21][22][23] The effects of long-term use is unclear, with some studies finding no effect on serum prolactin.[24][25][26] However, hyperprolactinemia has been reported in some chronic cannabis users,[27][28][29] and galactorrhea and hyperprolactinemia were reported in a woman who smoked marijuana for over 1 year.[29] The prolactin level in a mother with established lactation may not affect her ability to breastfeed. Of 258 mothers who reported smoking marijuana during pregnancy, 27 who had smoked marijuana during breastfeeding were followed-up at 1 year. No difference was found in the age of weaning between these mothers and 35 who reported not smoking marijuana during pregnancy or breastfeeding.[4] Colorado legalized medical cannabis in 2001 and recreational cannabis in 2012. A cross-sectional survey conducted in Colorado in 2014 and 2015 found that both prenatal and postnatal cannabis use were associated with a shorter duration of breastfeeding. Among women who reported using cannabis during pregnancy, 64% breastfed for 9 or more weeks compared with 78% of women who did not use cannabis during pregnancy. Among women who reported postpartum cannabis use, 58% breastfed for 9 weeks or more weeks compared with 79% of women who did not use cannabis postpartum. Both differences were statistically significant.[30] A study using a database of 4969 postpartum women found that those who reported using marijuana were more likely to smoke cigarettes, experience postpartum depressive symptoms, and breastfeed for less than 8 weeks.[31] Tobacco smoking is known to decrease the duration of breastfeeding, so the effect of marijuana is not clear. Most of the women who smoked marijuana postpartum also used it during pregnancy.