Cannabis Use in Pregnant and Breastfeeding Women: Behavioral and Neurobiological Consequences

Abstract

Nowadays, cannabis is the most consumed illicit drug. The global prevalence of the use of cannabis in 2017 was estimated in 188 million of people, 3.8% of worldwide population. Importantly, the legalization of cannabis in different countries, together with the increase in the apparent safety perception, may result in a great variety of health problems. Indeed, an important concern is the increase in cannabis use among pregnant and breastfeeding women, especially since the content of delta9-tetrahidrocannabinol (THC) is currently around 2-fold higher than it was 15-20 years ago. The purpose of this study was to review cannabis use during pregnancy and breastfeeding including epidemiological aspects, therapeutic or preventive strategies, and experimental considerations and results from animal models of perinatal cannabis exposure to analyze the underlying neurobiological mechanisms and to identify new therapeutic approaches. A recent report revealed that among pregnant women aged 15-44, last month cannabis use prevalence was over 4.9%, raising to 8.5% in the 18-25-year-old age range. Pre-and post-natal exposure to cannabis may be associated with critical alterations in the newborn infants that are prolonged throughout childhood and adolescence. Briefly, several reports revealed that perinatal cannabis exposure was associated with low birth weight, reduction in the head circumference, cognitive deficits (attention, learning, and memory), disturbances in emotional response leading to aggressiveness, high impulsivity, or affective disorders, and higher risk to develop a substance use disorder. Furthermore, important neurobiological alterations in different neuromodulatory and neurotransmission systems have been associated with cannabis consumption during pregnancy and lactation. In spite of the evidences pointing out the negative behavioral and neurobiological consequences of cannabis use in pregnant and breastfeeding women, there are still limitations to identify biomarkers that could help to establish preventive or therapeutic approaches. It is difficult to define the direct association specifically with cannabis, avoiding other confusing factors, co-occurrence of other drugs consumption (mainly nicotine and alcohol), lifestyle, or socioeconomic factors. Therefore, it is necessary to progress in the characterization of short-and long-term cannabis exposure-related disturbances.

Pregnant People's Perspectives On Cannabis Use During Pregnancy: A Systematic Review and Integrative Mixed‐Methods Research Synthesis

“…9,11,12,16,17 There are also inconsistent findings across studies as to whether prenatal cannabis use is associated with an increased risk for neonatal intensive care unit admission. 11,16,18 The evidence associating cannabis with neurodevelopmental outcomes in childhood is uncertain, 12,19 with some longitudinal studies suggesting there is an association between prenatal cannabis use and neurodevelopment as demonstrated through a variety of outcomes related to mental health, attention, hyperactivity, impulsivity in childhood, 20,21 whereas others have found no association. 22 Very few studies have analyzed the harms of cannabis exposure through lactation.…”

Brazilian Psychiatric Association consensus for the management of psychiatric emergencies in pregnancy and postpartum period

“…THC and other substances are known to cross the placental wall and are excreted in breastmilk [92]. Cannabis use may be associated with slow growth, spontaneous preterm birth, stillbirth, and admission to the neonatal intensive care unit on birth [93,94].…”

“…Behavioral measures must be the focus of treatment as there is limited data on the use of drugs to treat alcohol dependence (e.g., disulfiram, naltrexone, acamprosate) during pregnancy. Physicians must carefully weigh the risks of using such drugs versus alcohol use [84,87,[94][95][96].…”

The ethics and management of cannabis use in pregnancy following decriminalisation and licensing for medical use: narrative review

“…57 Cannabis use in pregnancy has also been associated with still-birth, preterm labour, low birth weight, 'small for gestational age' and two-fold increased risk of admission to a neonatal intensive care unit. [58][59][60] Gestational cannabis use may also be linked to maternal fatty liver, obesity, insulin resistance and increased risk of gestational diabetes mellitus (GDM). 61 In a more recent study, prenatal cannabis use was associated with a 50% increased likelihood of low birth weight, independent of confounders, although no association was found for small for gestational age, preterm birth and neonatal intensive care unit admission.…”