Abstract
This month's issue of Breastfeeding Medicine highlights the much anticipated publication of the revised Clinical Protocol (#21) of the Academy of Breastfeeding Medicine on the subject of “Breastfeeding in the Setting of Substance Use and Substance Use Disorder.” This most welcomed clinical management protocol details the pharmaco-kinetics and risks of substance use, thus, providing a basis for formulating breastfeeding recommendations for mothers who are using nonprescribed opioids, stimulants, sedative-hypnotic drugs, alcohol, nicotine, and cannabis substances.
In particular, the Protocol addresses the underlying concern that substance use in this critical postpartum period will potentially reduce parental ability to respond to infant feeding cues, while the infant's substance exposure through breast milk, risks an acute toxicity, reduction in breastfeeding ability, and “potential alterations in neonatal brain development.”
While the protocol discusses a wide range of substances that the mother is exposed to that might impact on the infant through its exposure by ingesting mothers' own breast milk, its reality, the most common substance that is used, both during pregnancy and while breastfeeding is cannabis. Given the fact that, to date, 38 states have legalized medical cannabis and that over 20 have legalized recreational cannabis use, it is not surprising that a prevalence of cannabis use during pregnancy as high as of 30% has been recorded in certain geographic areas in the United States. 1 Most strikingly, the increased rates of cannabis use have paralleled the COVID-19 pandemic suggesting cannabis use as a stress-relieving agent.
The recent report 2 of the longitudinal Adolescent Brain and Cognitive Developmental study wherein over 11,000 children were followed into adolescence documented that in utero exposure to cannabis was associated with long-term psychopathological adverse outcomes such as attention problems, diminished cognitive functioning, psychotic-like experiences, social problems, and documented lower brain volumes. These disturbing findings are in addition to the report 3 that in utero exposure is associated with an increased rate of intrauterine growth retardation, preterm births, and admissions to neonatal intensive care units.
What about infant cannabis exposure through ingestion of mother's milk. To date, there is a paucity of data to conclude that when there is only postpartum exposure are there any associated short or long-term adverse infant or childhood outcomes. For one, cannabis use by mothers after birth is almost always in a population that has also used cannabis prenatally, thus, any negative outcome data cannot be simply attributed to the infants postpartum exposure. Second, the potentially negative effect of cannabis exposure via breast milk is most likely offset by the neurotrophic and nutritional benefits of feeding human breast milk.
Thus, it is not surprising that the recommendations regarding the management of clinical situations where there is concern of fetal cannabis exposure are not the same as when the concern is postnatal infant exposure. Given the concern regarding the consequences of fetal in utero exposure, the following are absolute recommendations:
Categorically, mothers should desist from any cannabis use while pregnant and should stop its use while attempting to become pregnant. Women should immediately stop using cannabis once a pregnancy is diagnosed. From a public health perspective, in the context of the ongoing liberal legitimization of cannabis use, all such products should be explicitly labeled as detrimental to fetal health in the same manner as the existing warning re-ingesting alcoholic beverages while pregnant. Surely such warnings and labeling should not be any less than the printed health warning one finds on every pack of cigarettes. Yes, if cigarettes/smoking is detrimental on one's health no less so if cannabis exposure if detrimental to the fetus's short- and long-term health status.
On the other hand, given the absence of validated evidence based data on the effect of infant exposure to cannabis via the ingestion of breast milk, the most we can do is to encourage mothers to stop the use of cannabis or minimize as much as possible its use while they continue to provide human milk to their offspring. The data to date do not justify stopping breastfeeding in those situations even wherein it is clear that cannabis use is continuing. Simply put, the tradeoff regarding the benefits of feeding human milk most likely outweigh any theoretical negative effect of cannabis on the infant's development and growth.
This balanced set of recommendation is detailed in Academy of Breastfeeding Protocol #21 Protocol and its publication in Breastfeeding Medicine is thus most heartedly welcomed.