Although adverse effects of cannabinoids on pregnancy have been indicated for many years, the mechanisms by which they exert their actions were not clearly understood. Only recently, molecular and biochemical approaches have led to the identification of two types of cannabinoid receptors, brain-type receptors (CB1-R) and spleen-type receptors (CB2-R), which mediate cannabinoid effects. These findings were followed by the discovery of endocannabinoids, anandamide and 2-arachidonoylglycerol (2-AG). The natural cannabinoids and endocannabinoids exert their effects via cannabinoid receptors and share similar pharmacological and physiological properties. Recent demonstration of expression of functional CB1-R in the preimplantation embryo and synthesis of anandamide in the pregnant uterus of...

Prenatal marijuana exposure is associated with adverse perinatal effects. Very little is known about the effect of postnatal marijuana exposure on infant development. Postnatal exposure can result from maternal use of marijuana during lactation. Delta-9-tetrahydrocannabinol (THC) transfers and concentrates in the mother's milk and is absorbed and metabolized by the nursing infant. The present study investigated the relationship between infant exposure to marijuana via the mother's milk and infant motor and mental development at one year of age. One hundred and thirty-six breast-fed infants were assessed at one year of age for motor and mental development. Sixty-eight infants were exposed to marijuana via the...

The endocannabinoid system, including its receptors (CB1 and CB2), endogenous ligands (‘endocannabinoids’), synthesising and degrading enzymes, as well as transporter molecules, has been detected from the earliest stages of embryonic development and throughout pre- and postnatal development. In addition, the endocannabinoids, notably 2-arachidonyl glycerol, are also present in maternal milk. During three distinct developmental stages (i.e. embryonic implantation, prenatal brain development and postnatal suckling), the endocannabinoid system appears to play an essential role for development and survival. Thus, during early pregnancy, successful embryonic passage through the oviduct and implantation into the uterus both require critical enzymatic control of optimal anandamide levels at the appropriate...

OBJECTIVE: To identify neurobehavioral effects of prenatal marijuana exposure on neonates in rural Jamaica. DESIGN: Ethnographic field studies and standardized neuro-behavior assessments during the neonatal period. SETTING: Rural Jamaica in heavy-marijuana-using population. PARTICIPANTS: Twenty-four Jamaican neonates exposed to marijuana prenatally and 20 nonexposed neonates. MEASUREMENTS AND MAIN RESULTS: Exposed and nonexposed neonates were compared at 3 days and 1 month old, using the Brazelton Neonatal Assessment Scale, including supplementary items to capture possible subtle effects. There were no significant differences between exposed and nonexposed neonates on day 3. At 1 month, the exposed neonates showed better physiological stability and required less examiner facilitation to...