Reproductive and teratologic studies with Δ 9-tetrahydrocannabinol and crude marijuana extract

Abstract

Synthetic Δ 9-tetrahydrocannabinol ( Δ 9-THC) and crude marijuana extract (CME) containing 16% Δ 9-THC were administered orally to albino rats at doses of 0.5, 1.5, and 5 mg of Δ 9-THC from either source/kg body weight. In the general reproductive study, males were dosed from 60 days prior to mating until termination of mating and females were dosed from 14 days prior to mating until 21 days postpartum. Mating and fertility indices were similar for control and treatment groups. No differences between control and treatment groups were seen at an interim sacrifice on gestation Day 14 with respect to corpora lutea, implantation sites, resorption sites, and viable fetuses. The average numbers of pups delivered and viable at birth did not differ among control and treatment groups, and pup survival was unaffected by treatment. In a perinatal/lactation study, females were dosed from gestation Day 15 until lactation Day 21. No adverse effects of treatment were observed directly or in a cross-fostering study. No evidence of teratogenic activity was obtained for either Δ 9-THC or CME at Δ 9-THC equivalent doses of 5, 15, and 50 mg/kg on gestation Days 6–15 in rats and 0.5, 1.5, 5, and 15 mg/kg on gestation Days 6–18 in rabbits. Fetal survival and pup survival were reduced at the highest CME treatment level.