Cannabis Use in Pregnancy in British Columbia and Selected Birth Outcomes

Prenatal cannabis exposure and the risk for neuropsychiatric anomalies in the offspring: a systematic review and meta-analysis

OBJECTIVE

To evaluate the association between cannabis use during pregnancy and the risk for long-term neuropsychiatric pathology in the offspring.

DATA SOURCES

MEDLINE, EMBASE, and Cochrane library databases were systematically searched until January 22, 2024, with no language or date restrictions.

STUDY ELIGIBILITY CRITERIA

Studies were eligible for inclusion if they reported quantitative data on any long-term neuropsychiatric outcome in offspring whose mothers used cannabis during pregnancy for medical or recreational use, by any route and at any trimester, in comparison to offspring of women who abstained from cannabis use during pregnancy. All observational study designs were included in the analysis.

STUDY APPRAISAL AND SYNTHESIS METHODS

A systematic review and meta-analysis were performed according to the PRISMA and MOOSE guidelines. The data was extracted independently by 2 reviewers. The following offspring outcomes were of interest: attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), depression, anxiety, psychotic disorders, as well as cannabis and other substance use. Odds ratios (OR) and 95% confidence intervals (CI) were pooled for each neuropsychiatric outcome in the offspring of women exposed to cannabis during pregnancy compared with nonexposed. Data were pooled using random-effects models.

RESULTS

Eighteen eligible observational studies were included in the systematic review, and 17 were included in the final quantitative analysis, representing 534,445 participants. After adjusting for confounders, the pooled OR for ADHD was 1.13 (95% CI 1.01-1.26); for ASD, the pooled OR was 1.04 (95% CI 0.74-1.46); for psychotic symptoms, the pooled OR was 1.29 (95% CI 0.97-1.72); for anxiety, the pooled OR was 1.34 (95% CI 0.79-2.29); for depression, the pooled OR was 0.72 (95% CI 0.11-4.57); and for offspring's cannabis use, the pooled OR was 1.20 (95% CI 1.01-1.42).

CONCLUSION

Prenatal cannabis exposure is not associated with an increased risk of ASD, psychotic symptoms, anxiety, or depression in offspring. However, it may slightly elevate the risk of ADHD and predispose offspring to cannabis consumption. Despite these findings, caution is warranted regarding cannabis use during pregnancy. Further research is imperative, especially given the increasing potency of cannabis in recent years.

Changes in prenatal cannabis-related diagnosed disorders after the Cannabis Act and the COVID-19 pandemic in Quebec, Canada

BACKGROUND AND AIMS

Public health concerns regarding pregnant women's health after the enactment of the Cannabis Act in Canada (CAC) (a law that allowed non-medical cannabis use), and the potential impact of the COVID-19 pandemic, call for a contemporary assessment of these two events. Our study measured associations between the CAC, the COVID-19 pandemic and the monthly prevalence rates of cannabis-, all drug- and alcohol-related diagnosed disorders among pregnant women in the province of Quebec.

DESIGN, SETTING AND PARTICIPANTS

This was a quasi-experimental design applying an interrupted time-series methodology in the province of Quebec, Canada. The participants were pregnant women aged 15-49 years, between January 2010 and July 2022.

MEASUREMENTS

Administrative health data from the Québec Integrated Chronic Disease Surveillance System were used to classify pregnant women according to cannabis-, all drug (excluding cannabis)- and alcohol-related disorders. The CAC (October 2018) and the COVID-19 pandemic (April 2020) were evaluated as (1) slope changes and (2) level changes. Cannabis-, all drug (excluding cannabis)- and alcohol-related disorders were measured by total monthly age-standardized monthly prevalence rate of each disorder for pregnant women aged 15-49 years.

FINDINGS

Before the CAC, the prevalence rate of cannabis-related diagnosed disorders significantly increased each month by 0.5% [95% confidence interval (CI) = 0.3-0.6] in the pregnant population. After the CAC, there were significant increases of 24% (95% CI = 1-53) of cannabis-related diagnosed disorders. No significant changes were observed for all drug (excluding cannabis)- and alcohol-related diagnosed disorders associated with the CAC. A non-significant decrease of 20% (95% CI = -38 to 3) was observed during the COVID-19 pandemic in alcohol-related disorders.

CONCLUSIONS

The monthly incidence rates of diagnosed cannabis-related disorders in pregnant women in Quebec increased significantly following the enactment of the Cannabis Act in Canada. Diagnoses of all drug (excluding cannabis)- and alcohol-related disorders remained relatively stable.

Development and validation of the Cannabis Exposure in Pregnancy Tool (CEPT): a mixed methods study

BACKGROUND

Evidence of associations between prenatal cannabis use (PCU) and maternal and infant health outcomes remains conflicting amid broad legalization of cannabis across Canada and 40 American states. A critical limitation of existing evidence lies in the non-standardized and crude measurement of prenatal cannabis use (PCU), resulting in high risk of misclassification bias. We developed a standardized tool to comprehensively measure prenatal cannabis use in pregnant populations for research purposes.

METHODS

We conducted a mixed-methods, patient-oriented tool development and validation study, using a bias-minimizing process. Following an environmental scan and critical appraisal of existing prenatal substance use tools, we recruited pregnant participants via targeted social media advertising and obstetric clinics in Alberta, Canada. We conducted individual in-depth interviews and cognitive interviewing in separate sub-samples, to develop and refine our tool. We assessed convergent and discriminant validity internal consistency and 3-month test-retest reliability, and validated the tool externally against urine-THC bioassays.

RESULTS

Two hundred fifty four pregnant women participated. The 9-item Cannabis Exposure in Pregnancy Tool (CEPT) had excellent discriminant (Cohen's kappa = -0.27-0.15) and convergent (Cohen's kappa = 0.72-1.0) validity; as well as high internal consistency (Chronbach's alpha = 0.92), and very good test-retest reliability (weighted Kappa = 0.92, 95% C.I. [0.86-0.97]). The CEPT is valid against urine THC bioassay (sensitivity = 100%, specificity = 82%).

CONCLUSION

The CEPT is a novel, valid and reliable measure of frequency, timing, dose, and mode of PCU, in a contemporary sample of pregnant women. Using CEPT (compared to non-standardized tools) can improve measurement accuracy, and thus the quality of research examining PCU and maternal and child health outcomes.

Cannabis Use in Pregnancy and Neonatal Outcomes: A Systematic Review and Meta-Analysis

Objective: To determine whether prenatal cannabis use alone increases the likelihood of fetal and neonatal morbidity and mortality. Study Design: We searched bibliographic databases, such as PubMed, Embase, Scopus, Cochrane reviews, PsycInfo, MEDLINE, Clinicaltrials.gov, and Google Scholar from inception through February 14, 2022. Cohort or case-control studies with prespecified fetal or neonatal outcomes in pregnancies with prenatal cannabis use. Primary outcomes were preterm birth (PTB; <37 weeks of gestation), small-for-gestational-age (SGA), birthweight (grams), and perinatal mortality. Two independent reviewers screened studies. Studies were extracted by one reviewer and confirmed by a second using a predefined template. Risk of bias assessment of studies, using the Newcastle-Ottawa Quality Assessment Scale, and Grading of Recommendations Assessment, Development, and Evaluation for evaluating the certainty of evidence for select outcomes were performed by two independent reviewers with disagreements resolved by a third. Random effects meta-analyses were conducted, using adjusted and unadjusted effect estimates, to compare groups according to prenatal exposure to cannabis use status. Results: Fifty-three studies were included. Except for birthweight, unadjusted and adjusted meta-analyses had similar results. We found very-low- to low-certainty evidence that cannabis use during pregnancy was significantly associated with greater odds of PTB (adjusted odds ratio [aOR], 1.42; 95% confidence interval [CI], 1.19 to 1.69; I2, 93%; p=0.0001), SGA (aOR, 1.76; 95% CI, 1.52 to 2.05; I2, 86%; p<0.0001), and perinatal mortality (aOR, 1.5; 95% CI, 1.39 to 1.62; I2, 0%; p<0.0001), but not significantly different for birthweight (mean difference, -40.69 g; 95% CI, -124.22 to 42.83; I2, 85%; p=0.29). Because of substantial heterogeneity, we also conducted a narrative synthesis and found comparable results to meta-analyses. Conclusion: Prenatal cannabis use was associated with greater odds of PTB, SGA, and perinatal mortality even after accounting for prenatal tobacco use. However, our confidence in these findings is limited. Limitations of most existing studies was the failure to not include timing or quantity of cannabis use. This review can help guide health care providers with counseling, management, and addressing the limited existing safety data. Protocol Registration: PROSPERO CRD42020172343.

Alcohol and cannabis use among women with infertility: associations with psychiatric symptoms, attempts to conceive, and engagement in fertility treatment

Little is known about substance use among women with infertility, yet substance use has implications for fertility and pregnancy. The purpose was to estimate the prevalence of substance use among women with infertility and examine whether substance use was associated with psychiatric symptoms, active attempts to conceive, and engagement in fertility treatments. Eligible patients were from a single healthcare system who received a female infertility diagnosis within the past 2 years. Participants (n = 188) completed an online questionnaire regarding substance use, psychiatric symptoms, attempts to conceive, and fertility treatments. The prevalence of hazardous alcohol use, any cannabis use, and hazardous cannabis use were 30.3%, 30.9%, and 8.5%, respectively. Hazardous alcohol use was not associated with psychiatric symptoms (p > .05). Those with any cannabis use were more likely to have higher depression scores than those without (p = .02). Those with hazardous cannabis use were more likely to have higher depression scores (p = .001) and higher anxiety scores (p = .03). Substance use was not associated with actively trying to conceive. Those pursuing fertility treatments had a lower percentage engaging in hazardous alcohol use compared to those not pursuing fertility treatments (19.0% vs. 36.3%, p = .02). Substance use among women with infertility is common. Hazardous cannabis use was associated with greater psychiatric symptoms, suggesting that cannabis may be used to cope with distress. Pursuing fertility treatments may serve as a protective factor for hazardous alcohol use. Clinicians treating patients with infertility may want to screen for substance use.

Prenatal cannabis use and the risk of attention deficit hyperactivity disorder and autism spectrum disorder in offspring: A systematic review and meta-analysis

BACKGROUND

It is plausible that exposure to cannabis in-utero could be associated with an increased risk of neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD) symptoms and autism spectrum disorder (ASD) during childhood and adolescence; however, mixed results have been reported. This study investigated whether there is an association between prenatal cannabis use and ADHD symptoms and ASD in offspring using a systematic review and meta-analysis methodology.

METHODS

A systematic literature search was conducted in PubMed/Medline, Scopus, EMBASE, Web of Science, Psych-Info, and Google Scholar to identify relevant studies. The study protocol has been preregistered in the Prospective Register of Systematic Reviews (PROSPERO) (CRD42022345001), and the Newcastle-Ottawa Quality Assessment Scale (NOS) was used to assess the methodological quality of included studies. An inverse variance weighted random effect meta-analysis was conducted to pool the overall effect estimates from the included studies.

RESULTS

Fourteen primary studies, consisting of ten on ADHD and four on ASD, with a total of 203,783 participants, were included in this study. Our meta-analysis underscores an increased risk of ADHD symptoms and/or disorder [β = 0.39: 95 % CI (0.20-0.58), I2 = 66.85 %, P = 0.001)] and ASD [RR = 1.30: 95 % CI (1.03-1.64), I2 = 45.5 %, P = 0.14] associated with in-utero cannabis exposure in offspring compared to their non-exposed counterparts. Additionally, our stratified analysis highlighted an elevated risk of ADHD symptoms [β = 0.54: 95 % CI (0.26-0.82)] and a marginally significant increase in the risk of diagnostic ADHD among exposed offspring compared to non-exposed counterparts [RR = 1.13, 95 % CI (1.01, 1.26)].

CONCLUSION

This study indicated that maternal prenatal cannabis exposure is associated with a higher risk of ADHD symptoms and ASD in offspring.

Prenatal Exposure to Cannabis: Effects on Childhood Obesity and Cardiometabolic Health

PURPOSE OF REVIEW

To consolidate information on the obesogenic and cardiometabolic effects of prenatal exposure to cannabis.

RECENT FINDINGS

A PubMed search strategy updated from January 1, 2014, through 14 June 2023, produced a total of 47 epidemiologic studies and 12 animal studies. Prenatal exposure to cannabis is consistently associated with small for gestational age and low birth weight. After birth, these offspring gain weight rapidly and have increased adiposity and higher glucose (fat mass percentage) in childhood. More preclinical and prospective studies are needed to deepen our understanding of whether these associations vary by sex, dose, timing, and composition of cannabis (e.g., ratio of delta-Δ9-tetrahydrocannabinol [Δ9-THC] to cannabidiol [CBD]). Addressing these gaps may help to solidify causality and identify intervention strategies. Based on the available data, clinicians and public health officials should continue to caution against cannabis use during pregnancy to limit its potential obesogenic and adverse cardiometabolic effects on the offspring.

The Effects of Cannabis Use during Pregnancy on Low Birth Weight and Preterm Birth: A Systematic Review and Meta-analysis

OBJECTIVE

Our objective was to summarize the literature regarding the effects of cannabis use during pregnancy on low birth weight (LBW), preterm birth (PTB), and small for gestational age (SGA).

STUDY DESIGN

This is a systematic review and meta-analysis. A literature search was conducted in PubMed, Scopus, EBSCO, and Web of Science in May 2021 and updated in November 2021. Only studies that assessed the isolated use of cannabis during pregnancy, controlling for cigarette smoking, and other illicit drug use were included. Data were synthesized using a narrative summary and pooled adjusted estimates, and 95% confidence intervals (CIs) were calculated for each outcome. Data were analyzed using Stata 13.0 with METAN software package, using random effects. Statistical heterogeneity was assessed using Cochran's Q and Higgins I2 tests.

RESULTS

In total, 32 studies were included with data from approximately 5.5 million women with the LBW outcome and 23 million with the PTB and SGA outcomes. Pregnant women using cannabis are at increased risk for LBW (adjusted odds ratio [aOR] = 1.52; 95% CI = [1.18; 1.96]), PTB (aOR = 1.39; 95% CI = [1.28; 1.51]), and SGA (aOR = 1.47; 95% CI = [1.38; 1.58]). Studies that assessed the type of PTB and gestational age at birth indicate higher risks of spontaneous PTB and of early or very-early PTBs associated with cannabis use during pregnancy. The few studies that assessed the timing and frequency of consumption suggest a dose-response effect, with higher odds of negative outcomes among women who reported heavy use and with continued use during the second and third trimesters of gestation.

CONCLUSION

There is an effect of cannabis irrespective of other illicit drugs and tobacco despite high heterogeneity and low quality of evidence. There is a need to discuss public policies regarding cannabis' regulation and how it influences its consumption. Future studies should focus on the effects of cannabis's type (medicinal or recreational), timing, and dosage during pregnancy on perinatal outcomes.

KEY POINTS

· Cannabis use during pregnancy is increasing.. · Cannabis has an independent effect on PTB, LBW, and SGA.. · Future studies should focus on the timing of exposure during pregnancy, mode of use, and dosage..

Polysubstance use during pregnancy: The importance of screening, patient education, and integrating a harm reduction perspective

BACKGROUND

Substance use during pregnancy is associated with poor health outcomes. This study assessed substance use, polysubstance use, and use of select prescription medications during pregnancy.

METHODS

We analyzed 2019 data from the Pregnancy Risk Assessment Monitoring System in 25 United States jurisdictions that included questions on prescription medications, tobacco, and illicit substance use during pregnancy. Alcohol and electronic cigarette use were assessed during the last three months of pregnancy, and all other substances and medications were assessed throughout pregnancy. Weighted prevalence estimates and 95% confidence intervals (CIs) were calculated.

RESULTS

Nearly one-fifth of respondents who reported use of any substance reported use of at least one other substance during pregnancy. Cigarettes (8.1%; 95% CI 7.6-8.7%) and alcohol (7.4%; 95% CI 6.7-8.1%) were the most frequently reported substances, followed by cannabis (4.3%; 95% CI 3.9-4.7%). Substance use was higher among individuals who reported having depression or using antidepressants during pregnancy compared with those who did not report depression or antidepressant use. Illicit drug use prevalence was low (0.5%, 95% CI 0.4-0.7%); however, respondents reporting heroin use also frequently reported use of illicit stimulants (amphetamines: 51.7%, 95% CI 32.1-71.3% or cocaine: 26.5%, 95% CI 11.9-41.1%). Although prenatal clinician screening for alcohol and cigarette use was approximately 95%, fewer respondents (82.1%) reported being screened for cannabis or illicit substance use during pregnancy.

CONCLUSIONS

One in five individuals who reported use of any substance during pregnancy engaged in polysubstance use, highlighting the importance of comprehensive screening and evidence-based interventions including harm reduction.

Women are Taking the Hit: Examining the Unique Consequences of Cannabis Use Across the Female Lifespan

Cannabis use has risen dramatically in recent years due to global decriminalization and a resurgence in the interest of potential therapeutic benefits. While emerging research is shaping our understanding of the benefits and harms of cannabis, there remains a paucity of data specifically focused on how cannabis affects the female population. The female experience of cannabis use is unique, both in the societal context and because of the biological ramifications. This is increasingly important given the rise in cannabis potency, as well as the implications this has for the prevalence of Cannabis Use Disorder (CUD). Therefore, this scoping review aims to discuss the prevalence of cannabis use and CUD in women throughout their lifespan and provide a balanced prospective on the positive and negative consequences of cannabis use. In doing so, this review will highlight the necessity for continued research that goes beyond sex differences.

The effect of prenatal cannabis exposure on offspring preterm birth: a cumulative meta-analysis

BACKGROUND AND AIMS

Mixed results have been reported on the association between prenatal cannabis exposure and preterm birth. This study aimed to examine the magnitude and consistency of associations reported between prenatal cannabis exposure and preterm birth.

METHODS

This review was guided by the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. We performed a comprehensive search of the literature on the following electronic databases: PubMed, EMBASE, SCOPUS, Psych-INFO and Web of Science. The revised version of the Newcastle-Ottawa Scale (NOS) was used to appraise the methodological quality of the studies included in this review. Inverse variance weighted random-effects cumulative meta-analysis was undertaken to pool adjusted odds ratios (aOR) after sequential inclusion of each newly published study over time. The OR and 95% confidence interval (CI) limits required (stability threshold) for a new study to move the cumulative odds ratio to the null were also computed.

RESULTS

A total of 27 observational studies published between 1986 and 2022 were included in the final cumulative meta-analysis. The sample size of the studies ranged from 304 to 4.83 million births. Prenatal cannabis exposure was associated with an increased risk of preterm birth (pooled aOR = 1.35, 95% CI = 1.24-1.48). The stability threshold was 0.74 (95% CI limit = 0.81) by the end of 2022.

CONCLUSIONS

Offspring exposed to maternal prenatal cannabis use was associated with higher risk of preterm birth, which warrants public health messages to avoid such exposure, particularly during pregnancy.

Cannabis Use in Pregnancy and Downstream effects on maternal and infant health (CUPiD): a protocol for a birth cohort pilot study

INTRODUCTION

Cannabis use in pregnancy and post partum is increasing. Accessibility to cannabis has expanded due to the legalisation of cannabis in Canada. Therefore, there is a critical need to monitor the impact of cannabis on pregnancy outcomes and infant neurodevelopment. This pilot study will assess the feasibility of modern recruitment and data collection strategies adapted to the current cannabis environment and inform the design of a multicentre prospective birth cohort.

METHODS AND ANALYSIS

We will establish a pregnancy and birth cohort of 50 cannabis users and 50 non-users recruited before delivery. We will follow the participants at regular visits from recruitment to 12 weeks post partum. Participants will provide demographic and socioeconomic data, report their cannabis use patterns, and provide biological samples. Biological samples include maternal and infant urine and blood, breastmilk/chestmilk, cord blood, cord tissue, placenta and meconium. All samples will be processed and stored at -80°C until analysis by immunoassay or liquid chromatography-tandem mass spectrometry to determine the presence of cannabis metabolites. In addition, partners will be invited to provide additional socioeconomic and substance use data.

ETHICS AND DISSEMINATION

Ethics was obtained from Ottawa Health Science Network Research Ethics Board through Clinical Trials Ontario (3791). Our findings will be published in peer-reviewed journals, presented at scientific conferences and shared broadly with patients, healthcare decision-makers, and project partners online and through social media.

TRIAL REGISTRATION NUMBER

NCT05309226.Cite Now.

A Comprehensive Review on Social Inequalities and Pregnancy Outcome-Identification of Relevant Pathways and Mechanisms

Scientific literature tends to support the idea that the pregnancy and health status of fetuses and newborns can be affected by maternal, parental, and contextual characteristics. In addition, a growing body of evidence reports that social determinants, measured at individual and/or aggregated level(s), play a crucial role in fetal and newborn health. Numerous studies have found social factors (including maternal age and education, marital status, pregnancy intention, and socioeconomic status) to be linked to poor birth outcomes. Several have also suggested that beyond individual and contextual social characteristics, living environment and conditions (or "neighborhood") emerge as important determinants in health inequalities, particularly for pregnant women. Using a comprehensive review, we present a conceptual framework based on the work of both the Commission on Social Determinants of Health and the World Health Organization (WHO), aimed at describing the various pathways through which social characteristics can affect both pregnancy and fetal health, with a focus on the structural social determinants (such as socioeconomic and political context) that influence social position, as well as on intermediary determinants. We also suggest that social position may influence more specific intermediary health determinants; individuals may, on the basis of their social position, experience differences in environmental exposure and vulnerability to health-compromising living conditions. Our model highlights the fact that adverse birth outcomes, which inevitably lead to health inequity, may, in turn, affect the individual social position. In order to address both the inequalities that begin in utero and the disparities observed at birth, it is important for interventions to target various unhealthy behaviors and psychosocial conditions in early pregnancy. Health policy must, then, support: (i) midwifery availability and accessibility and (ii) enhanced multidisciplinary support for deprived pregnant women.

Cannabis use in pregnancy and maternal and infant outcomes: A Canadian cross-jurisdictional population-based cohort study

BACKGROUND

With the recent legalization of cannabis in Canada, there is an urgent need to understand the effect of cannabis use in pregnancy. Our population-based study investigated the effects of prenatal cannabis use on maternal and newborn outcomes, and modification by infant sex.

METHODS

The cohort included 1,280,447 singleton births from the British Columbia Perinatal Data Registry, the Better Outcomes Registry & Network Ontario, and the Perinatal Program Newfoundland Labrador from April 1st, 2012 to March 31st, 2019. Logistic regression determined the associations between prenatal cannabis use and low birth weight, small-for-gestational age, large-for-gestational age, spontaneous and medically indicated preterm birth, very preterm birth, stillbirth, major congenital anomalies, caesarean section, gestational diabetes and gestational hypertension. Models were adjusted for other substance use, socio-demographic and-economic characteristics, co-morbidities. Interaction terms were included to investigate modification by infant sex.

RESULTS

The prevalence of cannabis use in our cohort was approximately 2%. Prenatal cannabis use is associated with increased risks of spontaneous and medically indicated preterm birth (1.80[1.68-1.93] and 1.94[1.77-2.12], respectively), very preterm birth (1.73[1.48-2.02]), low birth weight (1.90[1.79-2.03]), small-for-gestational age (1.21[1.16-1.27]) and large-for-gestational age (1.06[1.01-1.12]), any major congenital anomaly (1.71[1.49-1.97]), caesarean section (1.13[1.09-1.17]), and gestational diabetes (1.32[1.23-1.42]). No association was found for stillbirth or gestational hypertension. Only small-for-gestational age (p = 0.03) and spontaneous preterm birth (p = 0.04) showed evidence of modification by infant sex.

CONCLUSIONS

Prenatal cannabis use increases the likelihood of preterm birth, low birth weight, small-for-gestational age and major congenital anomalies with prenatally exposed female infants showing evidence of increased susceptibility. Additional measures are needed to inform the public and providers of the inherent risks of cannabis exposure in pregnancy.

Is in-utero exposure to cannabis associated with the risk of attention deficit with or without hyperactivity disorder? A cohort study within the Quebec Pregnancy Cohort

IMPORTANCE AND OBJECTIVE

Prenatal cannabis effect on attention deficit with or without hyperactivity disorder (ADHD) remains to be determined. Our aim is to quantify the impact of in-utero exposure to cannabis on the risk of ADHD.

DESIGN

Cohort study.

SETTING

Questionnaires were mailed to women sampled from the Quebec Pregnancy Cohort (QPC). Data from questionnaires were then linked with their QPC (built with administrative health databases, hospital patient charts and birth certificate databases).

PARTICIPANTS

Respondents who gave birth to a singleton live born between January 1998 and December 2003 and were continuously enrolled in the Régie de l'assurance maladie du Québec (RAMQ) medication insurance plan for at least 12 months before the first day of gestation and during pregnancy.

EXPOSURE

In-utero cannabis exposure was based on mothers' answers to the question on cannabis use during pregnancy (yes/no) and categorised as occasionally, regularly exposed and unexposed if they chose one of these categories.

OUTCOMES

ADHD was defined by a diagnosis of ADHD through the RAMQ medical services or MedEcho databases or a prescription filled for ADHD medication through RAMQ pharmaceutical services between birth and the end of the follow-up period. Follow-up started at the birth and ended at the index date (first diagnosis or prescription filled for ADHD), child death (censoring), end of public coverage for medications (censoring) or the end of study period, which was December 2015 (censoring), whichever event came first.

RESULTS

A total of 2408 children met the inclusion criteria. Of these children, 86 (3.6%) were exposed to cannabis in-utero and 241 (10.0%) had an ADHD diagnosis or medication filled. After adjustments for potential confounders, no significant association was found between in-utero cannabis exposure (occasional (1.22 (95% CI 0.63 to 2.19)) or regular (1.22 (95% CI 0.42 to 2.79))) and the risk of ADHD in children.

CONCLUSIONS

In-utero exposure to cannabis seemed to not be associated with the risk ADHD in children.

Prenatal Exposure to Delta-9-tetrahydrocannabinol (THC) Alters the Expression of miR-122-5p and Its Target Igf1r in the Adult Rat Ovary

As cannabis use during pregnancy increases, it is important to understand its effects on the developing fetus. Particularly, the long-term effects of its psychoactive component, delta-9-tetrahydrocannabinol (THC), on the offspring’s reproductive health are not fully understood. This study examined the impact of gestational THC exposure on the miRNA profile in adult rat ovaries and the possible consequences on ovarian health. Prenatal THC exposure resulted in the differential expression of 12 out of 420 evaluated miRNAs. From the differentially expressed miRNAs, miR-122-5p, which is highly conserved among species, was the only upregulated target and had the greatest fold change. The upregulation of miR-122-5p and the downregulation of its target insulin-like growth factor 1 receptor (Igf1r) were confirmed by RT-qPCR. Prenatally THC-exposed ovaries had decreased IGF-1R-positive follicular cells and increased follicular apoptosis. Furthermore, THC decreased Igf1r expression in ovarian explants and granulosa cells after 48 h. As decreased IGF-1R has been associated with diminished ovarian health and fertility, we propose that these THC-induced changes may partially explain the altered ovarian follicle dynamics observed in THC-exposed offspring. Taken together, our data suggests that prenatal THC exposure may impact key pathways in the developing ovary, which could lead to subfertility or premature reproductive senescence.

Long-term effects of prenatal cannabis exposure: Pathways to adolescent and adult outcomes

With the increased prevalence, potency, and acceptability of cannabis use during pregnancy, it is important to understand the developmental effects of prenatal cannabis exposure (PCE). This review discusses methodological considerations for studies of PCE, including the assessment of exposures, covariates, and outcomes, and reviews findings from prospective, longitudinal studies of PCE. There is some evidence for associations between PCE and restricted growth at birth, but not for long-term effects on growth. PCE appears to have subtle yet enduring effects on memory and achievement in children and adolescents. Despite differences in sample demographics and measurement, there are remarkably consistent effects of PCE on externalizing behaviors, such as delinquency and substance use, which persist into adulthood. Longitudinal analyses demonstrate the importance of early cannabis initiation for pathways between PCE and adult functioning, including substance use and abuse, memory deficits, and psychotic symptoms. Animal studies demonstrate direct effects on the development of the brain via activation of endogenous endocannabinoid systems. Cannabis-induced activation of the endocannabinoid system causes alterations in the release of neurotransmitters and the modulation of brain plasticity in neural pathways that underlie cognition, motivation, and behavior regulation. Future research should consider cannabis use before pregnancy, the timing and route of exposure, polysubstance exposures, and inter-generational effects.

A perspective review of cannabis use and sexual offenses

Substance abuse is an established risk factor for crime and violence, including sexual violence. Nevertheless, the link between cannabis use and sexual offenses remains poorly understood. Cannabis use has a broad effect on sexual functioning and can have both acute and lasting adverse effects on psychological functioning, which in turn can elevate the risk of sexual offending behavior. Yet there is a scarcity of studies that have examined the link between cannabis use and sexual offending. To help fill the gap, this perspective review investigates the link between substance use and crime with a particular emphasis on cannabis use and its effects on sexual and psychological functioning. It then explores how these mechanisms may contribute to sexual offenses and recidivism, with a final discussion on how cannabis use should be conceptualized as a risk factor for sexual violence.

Maternal cannabis use during pregnancy and maternal and neonatal outcomes: A retrospective cohort study

OBJECTIVE

To examine the relationship between reported prenatal cannabis use and neonatal and maternal outcomes and whether the legalisation of cannabis in Canada affected the rates of reported use or the association with maternal and neonatal outcomes.

DESIGN

Population-based retrospective cohort study.

SETTING

Routinely collected data in a real-world setting.

POPULATION

All women in the Canadian province of Nova Scotia with singleton births between 1 January 2004 and 30 June 2021.

METHODS

The association between cannabis use and maternal and neonatal outcomes was examined using generalised linear models with inverse probability weighting.

MAIN OUTCOME MEASURES

Maternal and neonatal outcomes in the peripartum and postpartum period.

RESULTS

Rates of reported cannabis use in pregnancy increased from 1.3% to 7.5% over the study period with no appreciable change in slope after legalisation in 2018. Infants of mothers reporting cannabis use in pregnancy were more likely to have major anomalies and a 5-minute Apgar score ≤7, require neonatal intensive care unit admission, and had lower birthweight, head circumference and birth length than infants of mothers not reporting cannabis use. These associations did not differ before and after legalisation.

CONCLUSIONS

Reported cannabis use during pregnancy is associated with early postnatal complications and reduced fetal growth, even after taking into account a range of confounding factors. Rates of reported cannabis use during pregnancy increased over the past 5 years in Nova Scotia with no apparent additional effect of legalisation.

Applications of Cannabis Sativa L. in Food and Its Therapeutic Potential: From a Prohibited Drug to a Nutritional Supplement

Hemp (Cannabis sativa L.) is a herbaceous anemophilous plant that belongs to the Cannabinaceae family. The cannabis seed (hemp) has long been utilized as a food source and is commercially important as an edible oil source. In this review, the positive and negative health effects of cannabis, the relationship between cannabis and various diseases, and the use of cannabis in various food products have been discussed. In addition, the scientific literature on the potential use of cannabis and its derivatives as a dietary supplement for the prevention and treatment of inflammatory and chronic degenerative diseases in animals and humans has been reviewed. Cannabis is being developed as a key ingredient in a variety of food items, including bakery, confectionery, beverages, dairy, fruits, vegetables, and meat. Hemp seeds are high in readily digestible proteins, lipids, polyunsaturated fatty acids (PUFA), insoluble fiber, carbs, and favorable omega-6 PUFA acid to omega-3 PUFA ratio and have high nutritional value. The antioxidants of cannabis, such as polyphenols, help with anxiety, oxidative stress, and the risk of chronic illnesses, including cancer, neurological disorders, digestive problems, and skin diseases. Cannabis has been shown to have negative health impacts on the respiratory system, driving, and psychomotor functions, and the reproductive system. Overall, the purpose of this research is to stimulate more in-depth research on cannabis's adaptation in various foods and for the treatment of chronic illnesses.

The associations between prenatal cannabis use disorder and neonatal outcomes

BACKGROUND AND AIMS

Cannabis use disorder (CUD) during pregnancy has increased dramatically in the United States (US). This study examined the associations between prenatal CUD and adverse neonatal outcomes and heterogeneities in the associations by mothers' tobacco use status and race/ethnicity.

DESIGN

Population-based, retrospective cohort study.

SETTING

California, USA.

PARTICIPANTS

A total of 4.83 million mothers who delivered a live singleton birth during 2001 to 2012 and their paired infants. Data were obtained from mother-infant linked hospital discharge records and birth and death certificates. Identified by ICD-9 codes recorded at delivery, 20 237 mothers had prenatal CUD.

MEASUREMENTS

Neonatal outcomes included length of gestation, preterm birth, birth weight, admission into neonatal intensive care unit, hospitalization within 1 year of birth, and death within 1 year of birth. Propensity score matching was used to balance maternal, paternal, and infant characteristics in the comparisons between infants exposed and unexposed to prenatal CUD.

FINDINGS

CUD increased from 2.8 to 6.9 per 1000 deliveries during 2001 to 2012. Multivariable regressions in matched samples estimated that prenatal CUD was associated with greater odds of being small for gestational age (OR = 1.13, 95% CI = 1.08, 1.18), preterm birth (OR = 1.06, 95% CI = 1.01, 1.12), low birth weight (OR = 1.13, 95% CI = 1.07, 1.20), and death within 1 year of birth (OR = 1.35, 95% CI = 1.12, 1.62). Compared with infants whose mothers were tobacco non-users, infants whose mothers were tobacco users had greater odds of preterm birth, low birth weight, hospitalization, and death in association with prenatal CUD. Compared with infants whose mothers were non-Hispanic White, infants whose mothers were Hispanic had greater odds of hospitalization and death and infants whose mothers were non-Hispanic Black had greater odds of being small for gestational age in association with prenatal CUD.

CONCLUSION

Prenatal cannabis use disorder appears to be associated with escalated odds of major adverse neonatal outcomes, with heterogeneities in the associations by mothers' tobacco use status and race/ethnicity.

The Impact of Early Life Exposure to Cannabis: The Role of the Endocannabinoid System

Cannabis use during pregnancy has continued to rise, particularly in developed countries, as a result of the trend towards legalization and lack of consistent, evidence-based knowledge on the matter. While there is conflicting data regarding whether cannabis use during pregnancy leads to adverse outcomes such as stillbirth, preterm birth, low birthweight, or increased admission to neonatal intensive care units, investigations into long-term effects on the offspring’s health are limited. Historically, studies have focused on the neurobehavioral effects of prenatal cannabis exposure on the offspring. The effects of cannabis on other physiological aspects of the developing fetus have received less attention. Importantly, our knowledge about cannabinoid signaling in the placenta is also limited. The endocannabinoid system (ECS) is present at early stages of development and represents a potential target for exogenous cannabinoids in utero. The ECS is expressed in a broad range of tissues and influences a spectrum of cellular functions. The aim of this review is to explore the current evidence surrounding the effects of prenatal exposure to cannabinoids and the role of the ECS in the placenta and the developing fetus.

Marijuana Use during Pregnancy and Lactation and Long-term Outcomes

Recent surveys have shown increased use of marijuana during the perinatal period, possibly linked to increased legalization in many countries. Available information on the association between marijuana exposure and the effects on growth and development, as well as brain structure and function of the fetus, is growing but has not been uniform. Interpretation of these data is often challenging because of the influence of confounding factors and the sociodemographic variabilities in the study subjects. In this review, we present a synthesis of current information on the epidemiology and effects of marijuana use during pregnancy and evaluate the evidence for the immediate and long-term effects on affected neonates. We also describe the current knowledge and implications of breastfeeding and marijuana use and summarize selected current references about this practice. Finally, we provide the rationale for additional biological and population-based investigations to determine the various fetal outcomes of in-utero marijuana exposure that may assist in the establishment of prevention measures and applicable public health policies in the future.

The Effects of Cannabis on Female Reproductive Health Across the Life Course

Introduction: Cannabis is commonly used for its medicinal and therapeutic benefits and is also widely used as a recreational drug. Cannabis use has been increasing in Canada, including among Canadian women of reproductive age. Post-legalization, further increases in cannabis use are expected due to increased availability and lowered perceptions of harm. Although cannabinoids are well known for their effects on the central and peripheral nervous systems, endocannabinoid receptors have also been characterized throughout the female reproductive tract. Cannabinoids may affect many aspects of female reproductive health, including fertility, pregnancy outcomes with neonatal implications, and menopause. Purpose: To provide a comprehensive review of trends in cannabis use among women and review the impact of cannabis across the female reproductive lifespan. Methods: We searched PubMed and Cochrane Library databases using keywords and MeSH terms. Included studies reported the potential impact of cannabinoids on female fertility, pregnancy, transmission to breast milk, neonatal outcomes, and menopause. Results: The existing literature is primarily concentrated on the effect of cannabis use in pregnancy and breastfeeding, with little exploration of its impact on fertility and in later life. Studies are limited in number, with small sample sizes, and are hampered by methodological challenges related to confounding and other potential biases. Conclusions: There remain critical gaps in the literature about the potential risks of cannabis use, particularly in vulnerable populations, including pregnant women, women who are breastfeeding, and their infants. Given the rise in the prevalence of cannabis use, new, robust investigations into the consequences of cannabis exposure on female reproductive health are needed.

Alcohol and substance use in pregnancy during the COVID-19 pandemic

BACKGROUND

The impact of the COVID-19 pandemic on alcohol and substance use has been a topic of concern. Pregnant women are currently experiencing elevated anxiety and depression symptoms, which may increase risk of substance use, and potentially result in poor perinatal and neurodevelopmental outcomes for children.

METHODS

Survey results were analyzed from an ongoing study of 7470 pregnant individuals in Canada: Pregnancy during the COVID-19 Pandemic. Participants were asked about current use of alcohol and substances, symptoms of depression and anxiety, and COVID-19 concerns: how much they worry about COVID-19 threatening their baby's life, threatening their own life, care for themselves or the baby, feelings of social isolation, and financial difficulties.

RESULTS

The percentage of participants who reported use during pregnancy was 6.7 % for alcohol, 4.3 % for cannabis, 4.9 % for tobacco, and 0.3 % for illicit drugs; 2.6 % were using multiple substances. Higher depression symptoms and financial difficulties were associated with more cannabis and/or tobacco use as well as the co-use of substances. There were no associations between alcohol use and mental health or COVID-19 concerns.

CONCLUSIONS

Self-reported rates of use and co-use were lower or comparable to previous research, perhaps reflecting pandemic-related circumstances or the demographics of this sample. Depression symptoms and pandemic-related financial difficulties were associated with more tobacco use, cannabis use, and substance co-use. It remains important to maintain access to perinatal, mental health, and financial supports during the pandemic to mitigate prenatal alcohol and substance use and prevent poor perinatal and long-term neurodevelopmental outcomes for children.

Cannabis-related diagnosis in pregnancy and adverse maternal and infant outcomes

BACKGROUND

Cannabis use and cannabis use disorders are increasing in prevalence, including among pregnant women. The objective was to evaluate the association of a cannabis-related diagnosis (CRD) in pregnancy and adverse maternal and infant outcomes.

METHODS

We queried an administrative birth cohort of singleton deliveries in California between 2011-2017 linked to maternal and infant hospital discharge records. We classified pregnancies with CRD from International Classification of Disease codes. We identified nicotine and other substance-related diagnoses (SRD) in the same manner. Outcomes of interest included maternal (hypertensive disorders) and infant (prematurity, small for gestational age, NICU admission, major structural malformations) adverse outcomes.

RESULTS

From 3,067,069 pregnancies resulting in live births, 29,112 (1.0 %) had a CRD. CRD was associated with an increased risk of all outcomes studied; the strongest risks observed were for very preterm birth (aRR 1.4, 95 % CI 1.3, 1.6) and small for gestational age (aRR 1.4, 95 % CI 1.3, 1.4). When analyzed with or without co-exposure diagnoses, CRD alone conferred increased risk for all outcomes compared to no use. The strongest effects were seen for CRD with other SRD (preterm birth aRR 2.3, 95 % CI 2.2, 2.5; very preterm birth aRR 2.6, 95 % CI 2.3, 3.0; gastrointestinal malformations aRR 2.0, 95 % CI 1.6, 2.6). The findings were generally robust to unmeasured confounding and misclassification analyses.

CONCLUSIONS

CRD in pregnancy was associated with increased risk of adverse maternal and infant outcomes. Providing education and effective treatment for women with a CRD during prenatal care may improve maternal and infant health.

Cannabis and Cannabinoids in Reproduction and Fertility: Where We Stand

Although cannabis use is increasing in general population, their prevalence among young adults is remarkably high. In recent years, their medical use gained a renewed interest. However, it can underline the reputation of cannabis being a harmless drug. Between cannabinoids, uniquely found on the cannabis plant, Δ⁹-tetrahydrocannabinol (THC) is the well-studied compound. It is responsible for the psychoactive effects via central cannabinoid receptors. Nevertheless, cannabinoids interact with other chemical signalling systems such as the hypothalamic-pituitary-gonadal axis. THC indirectly decreases gonadotropin-releasing hormone (GnRH) secretion by the hypothalamus. The consequences are diverse, and several key hormones are affected. THC disturbs important reproductive events like folliculogenesis, ovulation and sperm maturation and function. Although generally accepted that cannabinoid consumption impacts male and female fertility, prevailing evidence remains largely on pre-clinical studies. Here, we introduce cannabinoids and the endocannabinoid system, and we review the most prominent clinical evidence about cannabis consumption in reproductive potential and teratogenicity.

Evidence for the Effectiveness and Acceptability of e-SBI or e-SBIRT in the Management of Alcohol and Illicit Substance Use in Pregnant and Post-partum Women

Alcohol and illicit psychoactive drug use during pregnancy have increased worldwide, putting women and their children's health and development at risk. Multiple drug use, comorbid psychiatric disorders, sexual and physical abuse are common in women who use alcohol and drugs during pregnancy. The effects on the mother include poor reproductive and life-long health, legal, family, and social problems. Additionally, the exposed child is at increased risk of long-term physical health, mental health, and developmental problems. The stigma associated with substance use during pregnancy and some clinicians' reticence to inquire about substance use means many women are not receiving adequate prenatal, substance abuse, and mental health care. Evidence for mHealth apps to provide health care for pregnant and post-partum women reveal the usability and effectiveness of these apps to reduce gestational weight gain, improve nutrition, promote smoking cessation and manage gestational diabetes mellitus, and treat depression and anxiety. Emerging evidence suggests mHealth technology using a public health approach of electronic screening, brief intervention, or referral to treatment (e-SBIRT) for substance use or abuse can overcome the typical barriers preventing women from receiving treatment for alcohol and drug use during pregnancy. This brief intervention delivered through a mobile device may be equally effective as SBIRT delivered by a health care professional in preventing maternal drug use, minimizing the effects to the exposed child, and providing a pathway to therapeutic options for a substance use disorder. However, larger studies in more diverse settings with women who have co-morbid mental illness and a constellation of social risk factors that are frequently associated with substance use disorders are needed.

Cannabis Use During the Pre-Conception Period and Pregnancy After Legalization

OBJECTIVE

There is limited evidence of the impact of cannabis legalization on the prevalence of cannabis use and use of other substances. The aim of this exploratory observational study was to compare rates of cannabis use, cigarette smoking, alcohol consumption, and the use of any street drugs during the preconception period and in pregnancy in two convenience samples of pregnant persons in British Columbia, Canada, before and after the legalization of cannabis.

METHODS

Any pregnant person residing in British Columbia, aged >19 years, at any gestational age was eligible to participate. Pre- and post-legalization study participants were recruited between May and October 2018 and July 2019 and May 2020, respectively. Multivariate models were constructed to examine the effect of legalization on cigarette smoking and the use of cannabis, alcohol, and street drugs, adjusting for demographic, pre-pregnancy, and pregnancy confounders.

RESULTS

From pre- to post-legalization, the prevalence of self-reported cannabis use during the preconception period increased significantly, from 11.74% (95% CI 9.19%-14.88%) to 19.38% (95% CI 15.45%-24.03%). Rates of cannabis use during pregnancy also increased from 3.64% (95% CI 2.32%-5.69%) before legalization to 4.62% (95% CI 2.82%-7.47%) after; however, this difference was not statistically significant. Adjusting for potential confounders, the post-legalization group had significantly higher odds of cannabis use during the preconception period (adjusted odds ratio 1.71; 95% CI 1.14-2.58) but not during pregnancy (adjusted odds ratio 1.66; 95% CI 0.75-3.65). Legalization was also not associated with significant changes in cigarette smoking, alcohol consumption, or the use of street drugs during the preconception period and pregnancy, after adjusting for potential confounders.

CONCLUSION

The preliminary evidence presented in this study shows that the legalization of cannabis was associated with 71% higher odds of cannabis use during the preconception period. Studies examining the effects of cannabis use on perinatal outcomes, as well as public health interventions and educational programs related to cannabis use, should include the preconception period as an area of focus.

Canadian educational resources about cannabis use and fertility, pregnancy and breast feeding: a scoping review protocol

INTRODUCTION

Cannabis use in Canada is becoming more prevalent across all demographic groups due to increases in accessibility and lowered perceptions of harm. These patterns are mirrored among women of reproductive age, including women who are pregnant. Given increasing evidence for detrimental short- and long-term impacts of cannabis exposure on fetal, newborn and child outcomes, there is a need for high-quality, accessible resources providing reliable guidance and recommendations on this topic for both the public and healthcare providers. We will conduct a scoping review to identify and characterise all publicly available online educational resources discussing cannabis use related to fertility, pregnancy and breastfeeding developed by Canadian organisations.

METHODS AND ANALYSIS

Using Arksey and O'Malley's scoping review methodology as a guide, we will search Medline (Ovid), Medline in Process (Ovid), Embase (Ovid), ERIC (Ovid), CINAHL (EBSCOhost) and Education Source (EBSCOhost). We will also conduct a grey literature search targeting the websites of national and independent Canadian obstetrical societies and networks, and government and public health offices that provide recommendations or guidance to individuals and their healthcare providers seeking information on cannabis use related to fertility, pregnancy or breastfeeding.

ETHICS AND DISSEMINATION

Research ethics approval is not required for scoping review studies. We anticipate that this review's findings will be disseminated through traditional channels, including preprint and peer-reviewed publications and presentations at academic conferences. In addition, the resources and guidelines identified in the study will be gathered and made available online on a single comprehensive public repository. PROTOCOL REGISTRATION NUMBER: osf.io/p24y5.

Maternal alcohol use, adverse neonatal outcomes and pregnancy complications in British Columbia, Canada: a population-based study

Background

The current study aimed to estimate the prevalence of alcohol use identified as a risk factor during pregnancies by the antenatal care providers, resulting in live births in British Columbia (BC) and to examine associations between alcohol use, adverse neonatal outcomes, and pregnancy complications.

Methods

This population-based cross-sectional study utilized linked obstetrical and neonatal records within the BC Perinatal Data Registry (BCPDR), for deliveries that were discharged between January 1, 2015 and March 31, 2018. The main outcome measures were alcohol use identified as a risk factor during pregnancy, associated maternal characteristics, pregnancy complications, and adverse neonatal outcomes. Estimates for the period and fiscal year prevalence were calculated. Chi-square tests were used to compare adverse neonatal outcomes and pregnancy complications by alcohol use during pregnancy identified as a risk factor. Logistic regression was used to examine the association between alcohol use identified as a risk factor during pregnancy and adverse neonatal outcomes and pregnancy complications, after adjusting for identified risk factors.

Results

A total of 144,779 linked records within the BCPDR were examined. The period prevalence of alcohol use during pregnancy identified as a risk factor was estimated to be 1.1% and yearly prevalence was 1.1, 1.1, 1.3 and 0.9% from the 2014/2015 to 2017/2018 fiscal years, respectively.

Alcohol use identified as a risk factor was associated with younger maternal age, fewer antenatal visits, being primiparous, a history of mental illness, substance use and smoking.

Neonates with alcohol use during pregnancy identified as a risk factor had greater odds of being diagnosed with: “low birth weight (1000-2499g)” (ICD-10: P07.1; aOR = 1.25; 95% CI: 1.01, 1.53), “other respiration distress of newborn” (ICD-10: P22.8; aOR = 2.57; 95% CI: 1.52, 4.07), “neonatal difficulty in breastfeeding” (ICD-10: P92.5; aOR = 1.97; 95% CI: 1.27, 2.92) and “feeding problems, unspecified” (ICD-10: P92.9; aOR = 2.06; 95% CI: 1.31, 3.09).

Conclusions

The prevalence of alcohol use during pregnancy identified as a risk factor was comparable to previous estimates within the BCPDR. Identified prenatal alcohol exposure was associated with notable differences in maternal and neonatal characteristics and adverse neonatal outcomes. More consistent, thorough screening and prevention efforts targeting alcohol use in pregnancy are urgently needed in Canada.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03545-7.

Association between maternal cannabis use and birth outcomes: an observational study

Background

As cannabis consumption is increasing globally, including among pregnant women, there is a critical need to understand the effects of cannabis on fetal development and birth outcomes. We had two objectives: to determine 1) the factors associated with self-reported cannabis use in the pre/early-pregnancy period, and 2) whether cannabis use is associated with low birth weight, preterm birth, or small size for gestational age (GA) infants.

Methods

Maternal questionnaire and birth outcome data was gathered from 2229 women and 1778 singleton infants in the Ontario Birth Study, a hospital-based prospective cohort study (2013–2019). Women self-reported cannabis use within 3 months of learning their pregnancy status. Multivariable linear and logistic regression was conducted to 1) identify factors associated with cannabis use, and 2) determine the associations between cannabis use with the selected birth outcomes.

Results

Cannabis use increased in the cohort over time. Women who reported cannabis use (N = 216) were more likely to be younger and more likely to use alcohol, tobacco, and prescription pain medication, although most did not. These women had infants born at lower average birth weights and had 2.0 times the odds of being small for GA (95% confidence interval: 1.3, 3.3) after multivariable adjustment for socioeconomic factors and other substance use.

Conclusion

Our results suggest that women who use cannabis around the time of conception have higher odds of having infants that are small for gestational age. Targeted clinical messaging may be most applicable to women actively trying to conceive.

Supplementary Information

Supplementary information accompanies this paper at 10.1186/s12884-020-03371-3.

Demographic Discrepancies in Prenatal Urine Drug Screening in Washington State Surrounding Recreational Marijuana Legalization and Accessibility

OBJECTIVES

This study evaluated demographic patterns related to prenatal cannabinoid urine drug screening (UDS) over a 5-year period during which recreational marijuana was legalized and became accessible in Washington State.

METHODS

Using electronic health record data, we performed a retrospective analysis for deliveries occurring over a 5-year period that encapsulated the transitions to marijuana legalization and legal access. For three cohorts of women delivering prior to legalization, between legalization and accessibility, and following accessibility, the UDS completion rate and screening demographic characteristics were assessed using Chi-squared tests and multivariate logistic regression.

RESULTS

25,514 deliveries occurred between March 2011 and March 2016. A significantly higher percentage of women underwent UDS post-accessibility (24.5%) compared to pre-legalization (20.0%, p < 0.001). A corresponding increase was not observed in the percentage of marijuana-positive UDS in tested patients (22.7% vs. 23.3%, p = 0.86). African American women had 2.8 times higher odds than Latinas of being tested, 2.1 times higher odds than Asian women, 1.7 times higher odds than White women, and 1.4 times higher odds than women of other races (all p < 0.001). Subsidized insurance status was also strongly associated with increased likelihood of testing (aOR = 3.5, p < 0.001).

CONCLUSIONS FOR PRACTICE

Prenatal UDS testing patterns changed as recreational marijuana possession and accessibility became legal. Demographic discrepancies in testing reveal biases related to race and insurance status, which may be a proxy for socioeconomic status. As such discrepancies are potential contributors to health outcome disparities, it is important for providers and health care systems to examine their practices and ensure they are being appropriately, equally, and justly applied.

Nurse home visiting and prenatal substance use in a socioeconomically disadvantaged population in British Columbia: analysis of prenatal secondary outcomes in an ongoing randomized controlled trial

BACKGROUND

Nurse-Family Partnership (NFP) involves public health nurses providing frequent home visits from early pregnancy until children reach age 2 years, focusing on first-time parents experiencing socioeconomic disadvantage. Our aim was to evaluate NFP's effectiveness in improving child and maternal health.

METHODS

We conducted an analysis of prenatal secondary outcomes in an ongoing randomized controlled trial in British Columbia; the data used in this analysis were collected from January 2014 to May 2017. Participants were pregnant girls and women aged 14-24 years who were preparing to parent for the first time and experiencing socioeconomic disadvantage. They were randomly allocated 1:1 to the intervention (NFP plus existing services) or control group (existing services). Prespecified prenatal secondary outcome indicators were changes in use of nicotine cigarettes and alcohol use by 34-36-weeks' gestation. We also report on prespecified exploratory cannabis and street drug use measures. We used mixed-effect models for longitudinal and clustered data to estimate intervention effects. Analyses were by intention to treat.

RESULTS

The median gestational age at baseline for the 739 participants (368 participants in the intervention group, 371 in the comparison group) was 20 weeks, 6 days. By 34-36 weeks' gestation, NFP significantly reduced cigarette counts (over the past 2 d) (difference in changes [DIC] of count -1.6, 95% confidence interval [CI] -6.4 to -1.3) in those who smoked. NFP also significantly reduced rates of prenatal cannabis use (DIC -6.4, 95% CI -17.0 to -1.7), but not rates of street drug or "any" substance use. While we observed decreased rates of cigarette and alcohol use in both groups (DIC of proportions -2.8, 95% CI -15.3 to 0.6; DIC -0.5, 95% CI -8.7 to 1.8, respectively), these changes were not statistically significant.

INTERPRETATION

We found no evidence that NFP was effective in reducing rates of prenatal cigarette and alcohol use; however, it led to reduced prenatal cannabis use, and in smokers it led to modest reductions in cigarette use. NFP may therefore hold promise for reducing some types of prenatal substance use in disadvantaged populations. Trial registration: ClinicalTrials.gov, no. NCT01672060.

Opioid and Cannabis Use During Pregnancy and Breastfeeding in Relation to Sociodemographics and Mental Health Status: A Descriptive Study

OBJECTIVE

This study of Canadian women estimates the prevalence of opioid and cannabis use during pregnancy and cannabis use during the breastfeeding period and explores the sociodemographic and mental health characteristics associated with use.

METHODS

A total of 13 000 women who gave birth between January and June 2018 were invited to participate in the Survey on Maternal Health by Statistics Canada; 7111 women participated for a response rate of 54.7%. Participants were asked about their mental health, supports during pregnancy, and substance use. Multivariable logistic regression was used to describe the relationship between sociodemographic and mental health characteristics and substance use during pregnancy and while breastfeeding.

RESULTS

The prevalence of self-reported opioid use during pregnancy was 1.4% (95% confidence interval [CI] 1.1%-1.8%). A higher proportion of women reported using cannabis during pregnancy and while breastfeeding, at 3.1% (95% CI 2.5%-3.6%) and 2.6% (95% CI 2.1%-3.1%), respectively. Younger age, not being in a relationship, lower level of education, and thoughts of self-harm were significantly associated with cannabis use during pregnancy. Lower level of education and thoughts of self-harm were also significantly associated with cannabis use while breastfeeding, as were symptoms of postpartum depression and/or generalized anxiety. Lower level of education and symptoms of postpartum depression and/or generalized anxiety were also significantly associated with opioid use during pregnancy.

CONCLUSION

The results of this survey show relatively low levels of opioid and cannabis use during pregnancy and cannabis use while breastfeeding in Canada. Different sociodemographic and mental health characteristics are associated with the use of these substances, and public health interventions and policies should take into account these factors.

Update on the developmental consequences of cannabis use during pregnancy and lactation

There is a strong increase in prevalence trends for cannabis use during pregnancy and lactation as more states legalize use of this drug. Information on the teratogenic risk of cannabis is limited but some important themes can be gleaned. Studies have not found a unique phenotypic signature of prenatal exposure but an increased risk of congenital anomalies, particularly gastroschisis, has been reported. Changes in fetal growth have been described in some epidemiological studies but long-term patterns of physical growth appear unaffected. Prenatal exposure to cannabis is not generally associated with reductions in global IQ but specific cognitive skills, especially attention and memory, can be negatively impacted. Long-term impacts on psychological health include increased rates of depressive symptoms and anxiety as well as delinquency. Relatively little is known about the risk of maternal cannabis use during lactation but data suggest that infant exposure is relatively low compared to maternal exposure. As delta-9-tetrahydrocannabinol (THC) levels increase to meet consumer demand and routes of exposure diversify, there is a strong need for prospective birth-cohort studies that collect biological samples to quantify exposure. Data from such studies will be critical to overcoming the weaknesses of past cannabis research and are essential to establishing reliable information on the risks of maternal use. Until that time, health care providers should be encouraged to talk about the risks and benefits associated with cannabis use during pregnancy and lactation with their patients, emphasizing that fetal and neonatal risks cannot be excluded at this time.

The association of cannabis use late in pregnancy with engagement and retention in perinatal substance use disorder care for opioid use disorder: A cohort comparison

BACKGROUND

Prenatal use of cannabis and opioids are increasing and very concerning. Engagement and retention in comprehensive, perinatal substance use disorder (PSUD) care are associated with better outcomes for mothers and babies. We compared the characteristics and engagement in care among women with opioid use disorder who used cannabis late in pregnancy versus those who didn't.

METHODS

The primary outcome, "overall engagement and retention in PSUD care" included: utilization of substance use treatment prenatally, negative screening/toxicology at delivery (excluding cannabis), and attendance at expected prenatal and postpartum visits. Cannabis use late in pregnancy was objectively assessed at delivery via maternal urine drug screen and/or neonatal meconium/cord toxicology. Between-group comparisons utilized chi square, t-test or Mann-Whitney. Associations were assessed using Spearman Rho and two multivariate, binary logistic regressions for cannabis use and the primary outcome.

RESULTS

18.0% (85/472) consumed cannabis late in pregnancy. Women of color, younger women, and those diagnosed with concurrent cannabis use disorder were more likely to consume cannabis. Engagement and retention in PSUD care was not associated with cannabis use, but rather, with prescribed pharmacotherapy for psychiatric disorders. The use of prescribed buprenorphine+naloxone was associated with cannabis avoidance late in pregnancy.

CONCLUSIONS

Cannabis use late in pregnancy, compared to none, did not impact engagement and retention in our PSUD program. Adjunctive psychotropic medication and/or buprenorphine+naloxone prescription were associated with cannabis avoidance suggesting the use and interactions of pharmacotherapies in an opioid dependent population is complex. A shared decision-making process during PSUD care is warranted.

Considerations and Implications of Cannabidiol Use During Pregnancy

PURPOSE OF REVIEW

Cannabis is a naturally occurring plant that is composed of over sixty phytocannabinoids, of which cannabidiol (CBD) has been recently identified as having therapeutic potential.

RECENT FINDINGS

Although not clearly understood in its mechanism of action, CBD contains potent anti-inflammatory, anti-hyperalgesia, and analgesic qualities now being further analyzed for its use in the treatment of a plethora of diseases. Related to its large safety profile and lack of psychoactive effects typically associated with cannabis and tetrahydrocannabinol (THC), CBD is being used more frequently for self-treatment of chronic pain, anxiety, and depression. With the help of broad marketing, CBD is being used by numerous people, including pregnant women who use CBD as an anti-emetic. Since marijuana is legalized in many states in the USA, the use of CBD has increased not only in the general population but also in specific groups such as pregnant women with chronic pain. Despite CBD's accessibility, there are limited studies showing its safety during pregnancy. While the use of cannabis has been well explored in terms of the effects on pregnancy, the use of CBD during pregnancy thus far has limited literature. The goal of this investigation is to impart the current understanding of CBD and its effects of pregnancy.

Cannabis and breastfeeding

Cannabis is one of the most commonly used substances in Canada with 15% of Canadians reporting use in 2019. There is emerging evidence that cannabis is linked to an impact on the developing brain in utero and adverse outcomes in infants, children, and adolescents. The impact of cannabis during breastfeeding has been limited by studies with small sample sizes, follow-up limited to 1 year and the challenge of separating prenatal exposure from that during breastfeeding. In the absence of high-quality evidence, health care providers need to continue to engage women in conversation about the potential concerns related to breastfeeding and cannabis use.

Pregnant Canadians' Perceptions About the Transmission of Cannabis in Pregnancy and While Breastfeeding and the Impact of Information From Health Care Providers on Discontinuation of Use

OBJECTIVE

Rates of cannabis use during pregnancy and while breastfeeding are increasing in Canada. Some observational studies have found associations between cannabis use in pregnancy and low birthweight, preterm labour, and admission to the intensive care unit. This study aimed to evaluate women's perceptions about transmission of cannabis to the fetus, and whether receiving information from a health care provider influenced their decision to stop using cannabis during pregnancy.

METHODS

Pregnant women presenting to obstetrical, midwifery, and family practice clinics in the greater Hamilton, Ontario area were asked to complete an anonymous survey. Chi-square tests were used to investigate whether patient knowledge was influenced by health care providers or by self-directed learning and if this information influenced their decision to discontinue cannabis use.

RESULTS

Of the 478 women surveyed, the vast majority perceived that cannabis is transmitted to the fetus during pregnancy and to the infant while breastfeeding (94.3% and 91.2%, respectively). The majority of women (99%) indicated that the advent of cannabis legalization did not influence their choice to use cannabis in pregnancy. Women who continued to use cannabis during pregnancy were more likely to report receiving information on cannabis from a health care provider (52%) than those who chose to discontinue use in pregnancy (35%) (P = 0.035).

CONCLUSIONS

In our study, the proportion of pregnant women who understood that cannabis could be transmitted to the fetus in utero and to the infant via breastmilk was high. Despite this, 4.2% of women reported that they continued to use cannabis in pregnancy. More work is needed to understand why some women continue to use cannabis in pregnancy despite being informed of its risks.

Effects of marijuana on human reproduction

As U.S. states steadily legalize its distribution and the prevalence of its use in people of reproductive age continues to rise, the need to understand the effects of marijuana on human physiology is becoming increasingly urgent. While marijuana is well-known for its psychoactive effects and applications in controlling pain and nausea, little is known about its effects on reproduction. This review includes in vitro studies which consistently demonstrate associations between marijuana consumption and low sperm count, dysregulated menstruation, and abnormal placentation. While many in vivo studies associate maternal marijuana use with stillbirth, neonatal intensive care unit (NICU) admission, and offspring psychosis, significant literature negates these relationships by controlling for poly-substance use and socioeconomic status. Data limited by self-reporting and confounds precludes the drawing of definitive conclusions regarding the effects of marijuana on reproduction. This review serves as a call to action to elucidate these effects and discourage marijuana use in people of reproductive age.

Monitoring Perinatal Exposure to Cannabis and Synthetic Cannabinoids

PURPOSE

Drug use during pregnancy is a critical global challenge, capable of severe impacts on neonatal development. However, the consumption of cannabis and synthetic cannabinoids is on the rise in pregnant women. Obstetric complications with increased risks of miscarriage, fetal growth restriction, and brain development impairment have been associated with perinatal cannabis exposure, but data on synthetic cannabinoid use during pregnancy are limited.

METHODS

We reviewed studies that investigated the risks associated with cannabis and synthetic cannabinoid use and those that reported the concentrations of cannabinoids and synthetic cannabinoids in maternal (breast milk) and neonatal (placenta, umbilical cord, meconium, and hair) matrices during human pregnancy. A MEDLINE and EMBASE literature search to identify all relevant articles published in English from January 1998 to April 2019 was performed.

RESULTS

Cannabis use during pregnancy is associated with increased risks of adverse obstetrical outcomes, although neurobehavioral effects are still unclear. Analyses of cannabinoids in meconium are well documented, but further research on other unconventional matrices is needed. Adverse effects due to perinatal synthetic cannabinoid exposure are still unknown, and analytical data are scarce.

CONCLUSIONS

Awareness of the hazards of drug use during pregnancy should be improved to encourage health care providers to urge pregnant women to abstain from cannabis and, if cannabis-dependent, seek treatment. Moreover, substances used throughout pregnancy should be monitored as a deterrent to cannabis use, and potential cannabis-dependent women should be identified, so as to limit cannabis-fetal exposure during gestation, and provided appropriate treatment.

Birth and early developmental screening outcomes associated with cannabis exposure during pregnancy

OBJECTIVE

To compare birth and early developmental screening outcomes for infants with and without in utero cannabis exposures.

STUDY DESIGN

Observational cohort of women receiving prenatal care within a large health system, live birth between October 1, 2015 and December 1, 2017, and at least one infant visit. Cannabis exposure was through routine urine toxicology screen. Preterm birth, small for gestational age (SGA) birth, birth defects, and early developmental screening outcomes were assessed from birth and electronic health record data.

RESULTS

Of 3435 women, 283 (8.2%) had a positive urine toxicology screen. In utero cannabis exposure was associated with SGA birth, adjusted rate ratio (aRR) 1.69 (95% confidence interval [CI]: 1.22-2.34). Abnormal 12-month developmental screens occurred in 9.1% of infants with in utero cannabis exposure vs. 3.6% of those with negative maternal screens, aRR 1.90 (95% CI: 0.92-3.91). Additional birth outcomes were not associated with in utero cannabis exposure.

CONCLUSIONS

Exposure to cannabis during pregnancy may adversely impact fetal growth.

Prenatal drug exposure and neurodevelopmental programming of glucocorticoid signalling

Prenatal neurodevelopment is dependent on precise functioning of multiple signalling pathways in the brain, including those mobilised by glucocorticoids (GC) and endocannabinoids (eCBs). Prenatal exposure to drugs of abuse, including opioids, alcohol, cocaine and cannabis, has been shown to not only impact GC signalling, but also alter functioning of the hypothalamic-pituitary-adrenal (HPA) axis. Such exposures can have long-lasting neurobehavioural consequences, including alterations in the stress response in the offspring. Furthermore, cannabis contains cannabinoids that signal via the eCB pathway, which is linked to some components of GC signalling in the adult brain. Given that GCs are frequently used in pregnancy to prevent complications of prematurity, and also that rates of cannabis use in pregnancy are increasing, the likelihood of foetal co-exposure to these compounds is high and may have additional implications for long-term neurodevelopment. Here, we present a discussion of GC signalling and the HPA axis, as well as the effects of prenatal drug exposure on these pathways and the stress response, and we explore the interactions between GC and EC signalling in the developing brain and potential for neurodevelopmental consequences.

Prevalence and outcomes of prenatal recreational cannabis use in high-income countries: a scoping review

BACKGROUND

With expanding recreational cannabis legalisation, pregnant women and their offspring are at risk of potentially harmful consequences.

OBJECTIVES

To assess the prevalence of recreational cannabis use among pregnant women, health outcomes associated with prenatal recreational cannabis use, and the potential impact of recreational cannabis legalisation on this population.

SEARCH STRATEGY

Five databases and the grey literature were systematically searched (2000-2019).

SELECTION CRITERIA

Human studies published in English or French reporting on the prevalence of prenatal recreational cannabis use in high-income countries.

DATA COLLECTION AND ANALYSIS

Data on study characteristics, prenatal substance use, and health outcomes were extracted and qualitatively synthesised.

MAIN RESULTS

Forty-one publications met our inclusion criteria. The overall prevalence of prenatal cannabis use varied substantially (min-max: 0.24-22.6%), with the greatest use in the first trimester. In the three studies with temporal data available, rates of prenatal cannabis use increased across years. Only 7/41 and 5/41 studies provided information on gestational age of exposure and frequency of use, respectively. The concomitant use of alcohol, illicit drugs, and tobacco was higher among cannabis users than nonusers. Prenatal cannabis use was associated with select neonatal, but not maternal, health outcomes. There were insufficient data to compare prenatal cannabis use between the pre- and post-legalisation periods.

CONCLUSION

Cannabis use among pregnant women is prevalent and may be associated with adverse neonatal outcomes. Future studies should assess the gestational age and frequency of cannabis exposure, and usage patterns prior to and following legalisation.

TWEETABLE ABSTRACT

Women who consume cannabis during pregnancy could risk predisposing their newborns to poor birth outcomes.