Thompson Mary, Vila Merima, Wang Li, Thabane Lehana, Shea Alison K
Department of Obstetrics and Gynecology, University of Calgary, Calgary, Alberta, Canada.
Department of Family Medicine, McMaster University, Hamilton, Ontario, Canada.
Paediatr Child Health. 2022 Oct 27;28(1):8-16. doi: 10.1093/pch/pxac079. eCollection 2023 Feb.
Cannabis is a widely used substance in pregnancy, yet there is a paucity of literature addressing the neuro-behavioural consequences for prenatally exposed children. Our systematic review synthesizes currently available data for the impact of prenatal cannabis use on offspring intelligence and cognitive functioning.
MEDLINE, EMBASE, PsychINFO, CINAHL, and Clinicaltrials.gov were searched. Observational studies comparing prenatal cannabis use to controls were included. Offspring neuro-behavioural outcomes were grouped in prespecified domains of (1) intelligence and (2) cognitive functioning. Random-effect models were performed for meta-analyses when at least three studies reported the same outcome. All others were summarized qualitatively. GRADE (Grading of Recommendations, Assessment, Development and Evaluations) framework was used to assess evidence certainty.
Of the 1982 reviewed studies (n = 523,107 patients), 28 were included. Significant heterogeneity and cohort redundancy limited meta-analysis. Very low-quality evidence from pooled analyses showed no significant associations between prenatal cannabis exposure and attention [standardized mean difference = -0.27 (95% CI = -0.60 to 0.07)], global intelligence quotient [-0.16 (-0.42 to 0.10)], reading [-0.05 (-0.29 to 0.20)], written comprehension [-0.09 (-0.40 to 0.22)], spelling [-0.04 (-0.26 to 0.17)], and mathematics [-0.01 (-0.15 to 0.13)]. No significant associations were found between prenatal cannabis exposure for all other outcomes. Individual studies reported significant differences between the heavy use groups and non-exposed, although this did not prove to be significant when outcomes were pooled.
The current review did not find a clear association between prenatal cannabis use and offspring neuro-behavioural outcomes. However, evidence was low quality and heterogenous. Further prospective investigation is needed to elucidate any potential association between prenatal cannabis use and long-term neuro-developmental outcomes.
大麻是孕期广泛使用的物质，但针对产前接触大麻的儿童的神经行为后果的文献却很匮乏。我们的系统评价综合了目前关于产前使用大麻对后代智力和认知功能影响的现有数据。
检索了MEDLINE、EMBASE、PsychINFO、CINAHL和Clinicaltrials.gov。纳入了比较产前使用大麻与对照组的观察性研究。后代神经行为结果分为预先指定的领域：（1）智力和（2）认知功能。当至少三项研究报告相同结果时，采用随机效应模型进行荟萃分析。所有其他研究进行定性总结。采用GRADE（推荐分级、评估、制定和评价）框架评估证据的确定性。
在1982项纳入综述的研究（n = 523,107例患者）中，28项被纳入。显著的异质性和队列冗余限制了荟萃分析。汇总分析得出的极低质量证据表明，产前接触大麻与注意力[标准化均值差=-0.27（95%置信区间=-0.60至0.07）]、全球智商[-0.16（-0.42至0.10）]、阅读[-0.05（-0.29至0.20）]、书面理解[-0.09（-0.40至0.22）]、拼写[-0.04（-0.26至0.17）]和数学[-0.01（-0.15至0.13）]之间无显著关联。产前接触大麻与所有其他结果之间均未发现显著关联。个别研究报告了大量使用组与未接触组之间的显著差异，但汇总结果时未证明具有显著性。
当前综述未发现产前使用大麻与后代神经行为结果之间存在明确关联。然而，证据质量低且存在异质性。需要进一步进行前瞻性研究，以阐明产前使用大麻与长期神经发育结果之间的任何潜在关联。
