Behavioral effects on the offspring of rodent mothers exposed to Tetrahydrocannabinol (THC): A meta-analysis

Abstract

Pre and perinatal administration of Tetrahydrocannabinol (THC) in rodents
and their offspring has many effects that have been studied using different
methods that have not been integrated using quantitative methods. The effect
of THC administration on behavior can be better understood by meta-analytic
techniques. We examined whether there is an overall effect on the behavior of
the offspring when THC is administered to mothers. Eligibility criteria included
experiments using an experimental design with a control group without THC,
in which THC is administered to mothers during pregnancy and lactation in
rodents, and in which at least one type of behavioral (locomotor, emotional
or cognitive) measurement in the offspring was implemented. Cohen’s d
was obtained for each study, then each individual study was weighted, and
moderator analysis was performed. Analysis was performed using fixed and
random effect models, and the heterogeneity was assessed by calculating
Qb, I
2 and the prediction interval. Furthermore, 3 sub-meta-analyses were
carried out according to the type of behavior. The general analysis determined
a low weighted effect size of THC on the behavior of the offspring, moderated
by type of rat strain. The sub-meta-analyses showed a medium effect for
cognitive effects of THC in the offspring, and a low effect on locomotor
activity and emotional behavior. In addition, publication bias was not detected.
More research is needed to contribute to the understanding of the effect of
THC exposure on offspring.