Using bayesian models to assess the effects of under-reporting of cannabis use on the association with birth defects, national birth defects prevention study, 1997-2005

The association between prenatal cannabis use and congenital birth defects in offspring: A cumulative meta-analysis

OBJECTIVE

To examine the association between prenatal cannabis use and structural birth defects in exposed offspring.

METHODS

In line with the preregistered protocol (PROSPERO: CRD42022368623), we systematically searched PubMed/Medline, CINHAL, EMBASE, Web of Science, ProQuest, Psych-Info, and Google Scholar for published articles until 25 January 2024. The methodological quality of the included studies was appraised by the Newcastle-Ottawa Quality Assessment Scale (NOS). A meta-analysis was carried out to report the pooled effect estimates from the included studies. We further performed subgroup, leave-one-out sensitivity, and meta-regression analyses, which increased the robustness of our findings.

RESULTS

In this cumulative meta-analysis, thirty-six observational studies, consisting of 18 case-control and 18 cohort studies, with 230, 816 cases of birth defects and 18,049,013 controls (healthy babies) were included in the final analysis. We found that offspring exposed to maternal prenatal cannabis are at greater risks of a wide range of structural birth defects: cardiovascular/heart [OR = 2.35: 95 % CI 1.63 - 3.39], gastrointestinal [OR = 2.42: 95 % CI 1.61 - 3.64], central nervous system [OR = 2.87: 95 % CI 1.51 - 5.46], genitourinary [OR = 2.39: 95 % CI 1.11 - 5.17], and any (unclassified) birth defects [OR = 1.25: 95 % CI 1.12 - 1.41].

CONCLUSION

The findings from the current study suggest that maternal prenatal cannabis exposure is associated with a higher risk of different forms of structural birth defects in offspring. The findings underscore the significance of implementing preventive strategies, including enhanced preconception counselling, to address cannabis use during pregnancy and mitigate the risk of birth defects in 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..

Prenatal Exposure to Cannabis and Risk of Major Structural Birth Defects: A Systematic Review and Meta-analysis

OBJECTIVE

To review and perform a meta-analysis of observational studies that examined associations between prenatal cannabis exposure and major structural birth defects.

DATA SOURCES

Information sources included Google Scholar, BIOSIS, PubMed/MEDLINE, EMBASE CINAHL, and ClinicalTrials.gov.

METHODS OF STUDY SELECTION

Study titles and abstracts were reviewed with Abstrackr software. We included observational studies that examined the risk of major structural birth defects in people who used cannabis during pregnancy compared with those who had not used cannabis. We excluded case reports, ecologic studies, conference abstracts, manuscript preprints, studies designed to examine effects of cannabis used concurrently with other drugs, and studies that included synthetic cannabinoids. This process yielded 23 studies that analyzed data from birth years 1968-2021.

TABULATION, INTEGRATION, AND RESULTS

We clustered and meta-analyzed measures of association for birth defects by anatomic group. Eleven articles reported an association between cannabis use and the risk of a nonspecific outcome (eg, congenital anomaly). We estimated a pooled odds ratio of 1.33 (95% CI 1.14-1.56) and a pooled adjusted odds ratio (aOR) of 1.22 (95% CI 1.00-1.50). Anatomic groups examined were cardiac (nine studies), oral cleft (three studies), digestive (four studies), genitourinary (three studies), musculoskeletal (seven studies), and nervous system (five studies). Across most outcomes, we reported positive pooled unadjusted associations that were usually attenuated after the inclusion of only adjusted estimates. Two specific anomalies, with limited data, had pooled effect estimates that did not attenuate to the null after adjustment: Ebstein anomaly (two studies, aOR 2.19, 95% CI 1.25-3.82) and gastroschisis (five studies, aOR 2.50, 95% CI 1.09-5.740).

CONCLUSION

Studies examining associations between prenatal exposure to cannabis and major structural birth defects were heterogeneous. Most published effect estimates were unadjusted and scored low on our risk-of-bias assessment. Overall, we found inconsistent evidence to suggest that prenatal cannabis exposure is associated with birth defects. However, findings related to specific anomalies should be considered in further research.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42022319041.

Cannabis and Pregnancy: A Review

Importance

Prenatal cannabis use is rising and is a major public health issue. Cannabis use in pregnancy and during lactation has been associated with increased maternal and offspring morbidity and mortality.

Objective

This review aims to summarize the existing literature and current recommendations for cannabis use during pregnancy or lactation.

Evidence Acquisition

A PubMed, Cochrane Library, and Google Scholar literature search using the following terms was performed to gather relevant data: "cannabis," "cannabinoid," "delta-9-tetrahydrocannabinol," "THC," "cannabidiol," "fetal outcomes," "perinatal outcomes," "pregnancy," and "lactation."

Results

Available studies on cannabis use in pregnancy and during lactation were reviewed and support an association with increased risk of preterm birth, neonatal intensive care unit admission, low birth weight, and small-for-gestational-age infants.

Conclusion and Relevance

There is a critical need for research on the effects of cannabis use in pregnancy and during lactation. This is a necessary first step before furthering patient education, developing interventions, and targeting antenatal surveillance to ameliorate the adverse impacts on maternal and fetal health.

A systematic review of in utero cannabis exposure and risk for structural birth defects

Introduction

Cannabis use among pregnant women has increased over time. Therefore, there is a great public health need to understand the consequences of in utero cannabis exposure. While several meta-analyses and reviews have summarized the evidence of in utero cannabis exposure on adverse obstetric outcomes (e.g., low birth weight and preterm birth) and long-term offspring development, there has not been a focus on in utero cannabis exposure and risk for structural birth defects.

Methods

We conducted a systematic review using PRISMA guidelines to evaluate the association between in utero cannabis exposure and structural birth defects.

Results

We identified 20 articles to include in our review and focused on interpreting findings from the 12 that adjusted for potential confounders. We report findings by seven organ systems. Within the 12 articles, four reported on cardiac malformations, three reported on central nervous system malformations, one reported on eye malformations, three reported on gastrointestinal malformations, one reported on genitourinary malformations, one reported on musculoskeletal malformations, and two reported on orofacial malformations.

Discussion

Findings on associations between in utero cannabis exposure and birth defects reported in more than two articles were mixed (i.e., findings for cardiac, gastrointestinal, central nervous system malformations). Findings for associations between in utero cannabis exposure and birth defects reported in two articles (i.e., orofacial malformations) or in a single article (eye, genitourinary, and musculoskeletal) suggested that cannabis exposure was not associated with these types of malformations, but strong conclusions cannot be drawn from such sparce research. We review the limitations and gaps in the existing literature and call for more research to rigorously evaluate associations between in utero cannabis exposure and structural birth defects.

Systematic Review Registration

identifier CRD42022308130.

Impact of Prenatal Cannabis Use Disorder on Perinatal Outcomes

OBJECTIVES

With legislative changes to cannabis legalization and increasing prevalence of use, cannabis is the most commonly used federally illicit drug in pregnancy. Our study aims to assess the perinatal outcomes associated with prenatal cannabis use disorder.

METHODS

We conducted a retrospective cohort study using California linked hospital discharge-vital statistics data and included singleton, nonanomalous births occurring between 23 and 42 weeks of gestational age. χ 2 Test and multivariable logistic regression were used for statistical analyses.

RESULTS

A total of 2,380,446 patients were included, and 9144 (0.38%) were identified as using cannabis during pregnancy. There was a significantly increased risk for adverse birthing person outcomes, including gestational hypertension (adjusted odds ratio [AOR], 1.19; 95% confidence interval [CI], 1.06-1.34; P = 0.004), preeclampsia (AOR, 1.16; 95% CI, 1.0-1.28; P = 0.006), preterm delivery (AOR, 1.45; 95% CI, 1.35-1.55; P < 0.001), and severe maternal morbidity (AOR, 1.22; 95% CI, 1.02-1.47; P = 0.033). Prenatal cannabis use disorder was also associated with an increased risk of neonatal outcomes including respiratory distress syndrome (AOR, 1.16; 95% CI, 1.07-1.27; P < 0.001), small for gestational age (AOR, 1.47; 95% CI, 1.38-1.56; P < 0.001), neonatal intensive care unit admission (AOR, 1.24; 95% CI, 1.16-1.33; P < 0.001), and infant death (AOR, 1.86; 95% CI, 1.44-2.41; P < 0.001). There was no statistically significant difference in stillbirth (AOR, 0.96; 95% CI, 0.69-1.34; P = 0.80) and hypoglycemia (AOR, 1.22; 95% CI, 1.00-1.49; P = 0.045).

CONCLUSIONS

Our study suggests that prenatal cannabis use disorder is associated with increased maternal and neonatal morbidity and mortality. As cannabis use disorder in pregnancy is becoming more prevalent, our findings can help guide preconception and prenatal counseling.

Congenital Gastrointestinal Anomalies in Europe 2010–2019: A Geo-Spatiotemporal and Causal Inferential Study of Epidemiological Patterns in Relationship to Cannabis- and Substance Exposure

Introduction: Congenital anomalies (CA’s) of most of the gastrointestinal tract have been linked causally with prenatal or community cannabis exposure. Therefore, we studied this relationship in Europe. Methods: CA data were from Eurocat. Drug-use data were sourced from the European Monitoring Centre for Drugs and Drug Addiction. Income data were taken from the World Bank. Results: When countries with increasing rates of daily cannabis use were compared with those which were not, the overall rate of gastrointestinal CA’s (GCA’s) was higher in the former group (p = 0.0032). The five anomalies which were related to the metrics of cannabis exposure on bivariate analysis were bile duct atresia, Hirschsprungs, digestive disorders, annular pancreas and anorectal stenosis or atresia. The following sequence of GCA’s was significantly linked with cannabis metrics at inverse-probability-weighted-panel modelling, as indicated: esophageal stenosis or atresia, bile duct atresia, small intestinal stenosis or atresia, anorectal stenosis or atresia, Hirschsprungs disease: p = 1.83 × 10−5, 0.0046, 3.55 × 10−12, 7.35 × 10−6 and 2.00 × 10−12, respectively. When this GCA series was considered in geospatial modelling, the GCA’s were significantly cannabis-related from p = 0.0003, N.S., 0.0086, 6.652 × 10−5, 0.0002, 71.4% of 35 E-value estimates and 54.3% minimum E-values (mEVv’s) > 9 (high zone) and 100% and 97.1% > 1.25 (causality threshold). The order of cannabis sensitivity by median mEVv was Hirschsprungs > esophageal atresia > small intestinal atresia > anorectal atresia > bile duct atresia. Conclusions: Seven of eight GCA’s were related to cannabis exposure and fulfilled the quantitative criteria for epidemiologically causal relationships. Penetration of cannabinoids into the community should be carefully scrutinized and controlled to protect against exponential and multigenerational genotoxicity ensuing from multiple cannabinoids.

European Epidemiological Patterns of Cannabis- and Substance-Related Congenital Neurological Anomalies: Geospatiotemporal and Causal Inferential Study

Introduction. Of the many congenital anomalies (CAs) recently linked with community cannabis exposure, arguably the most concerning are neurological CAs (NCAs). We therefore conducted a detailed study of this in fourteen European nations. Methods. Congenital anomaly data were from Eurocat. Drug exposure data were from European Monitoring Centre for Drugs and Drug Addiction. Income from World bank. Results. The Netherlands, Spain, France and Bulgaria reported increasing rates of many NCAs. The NCA rate (NCAR) was higher in nations with increasing daily cannabis use when compared to those without (p = 0.0204, minimum E-value (mEV) = 1.35). At bivariate analysis, the mEVs of the following NCAs were significantly cannabis related: severe microcephaly 2.14 × 1013, craniosynostosis 5.27 × 1011, nervous system 4.87 × 1011, eye 2.73 × 107, microphthalmos 4.07 × 106, anencephalus 710.37, hydrocephalus 245.64, spina bifida 14.86 and neural tube defects 13.15. At inverse probability, weighted panel regression terms including cannabis were significantly related to the following series of anomalies: nervous system, anencephalus, severe microcephalus, microphthalmos, neural tube defect and spina bifida from p = 5.09 × 10−8, <2.2 × 10−16, <2.2 × 10−16, 4.84 × 10−11, <2.2 × 10−16 and 9.69 × 10−7. At geospatial regression, this same series of anomalies had terms including cannabis significant from p = 0.0027, 1.53 × 10−7, 3.65 × 10−6, 2.13 × 10−8, 0.0002 and 9.76 × 10−12. 88.0% of 50 E-value estimates and 72.0% of mEVs > 9. This analysis therefore demonstrates both close association of cannabis exposure with multiple NCAs across space-time and also fulfills the quantitative criteria of causal inferential analysis. Conclusions. Nine NCARs on bivariate and six NCARs on multivariable regression were cannabis related and fulfilled quantitative epidemiological criteria for causality and are consistent with other series. Particular concerns relate to exponential dose−response effects demonstrated in the laboratory and epidemiological studies. Great caution with community cannabinoid penetration is warranted. Data indicate that cannabis is a significant environmental teratogen and thus imply that cannabinoids should be regulated similarly to the manner in which all other important genotoxins are carefully controlled by communities for their self-sustaining longevity and the protection of generations yet to come.

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.

European Epidemiological Patterns of Cannabis- and Substance-Related Body Wall Congenital Anomalies: Geospatiotemporal and Causal Inferential Study

As body wall congenital anomalies (BWCAs) have a long history of being associated with prenatal or community cannabis exposure (CCE), it was of interest to investigate these epidemiological relationships in Europe given the recent increases in cannabis use prevalence, daily intensity, and Δ9-tetrahydrocannabinol (THC) potency. Methods: This study makes use of BWCA data from Eurocat, drug exposure data from the European Monitoring Centre for Drugs and Drug Addiction, and income from the World Bank. Results: The mapping analysis showed that BWCARs increased in France, Spain, and the Netherlands. The bivariate mapping analysis showed that the BWCA rates (BWCAR) and the cannabis resin THC concentration rose simultaneously in France, the Netherlands, Bulgaria, Sweden, and Norway. The bivariate ranking of the BWCARs by median minimum E-value (mEV) was omphalocele > diaphragmatic hernia > abdominal wall defects > gastroschisis. With inverse probability weighted multivariable panel regression, the series of BWCAs, including gastroschisis, omphalocele, and diaphragmatic hernia, was positively related to various metrics of cannabis use from p = 2.45 × 10−14, 4.77 × 10−7 and <2.2 × 10−16. With geospatial regression, the same series of BWCAs was related to cannabis metrics from p = 0.0016, 5.28 × 10−6 and 4.88 × 10−9. Seventeen out of twenty-eight (60.7%) of the E-value estimates were >9 (high range), as were 14/28 (50.0%) of the mEVs. Conclusion: The data confirm the close relationship of the BWCARs with the metrics of CCE, fulfill the quantitative criteria of causal inference, and underscore the salience of the public health impacts of cannabinoid teratogenicity. Of major concern is the rising CCE impacting exponential cannabinoid genotoxic dose-response relationships. CCE should be carefully restricted to protect the food chain, the genome, and the epigenome of coming generations.

Impact of converging sociocultural and substance-related trends on US autism rates: combined geospatiotemporal and causal inferential analysis

Whilst cannabis is known to be toxic to brain development, it is unknown if it is driving rising US autism rates (ASMR). A longitudinal epidemiological study was conducted using national autism census data from the US Department of Education Individuals with Disabilities Act (IDEA) 1991-2011 and nationally representative drug exposure (cigarettes, alcohol, analgesic, and cocaine abuse, and cannabis use monthly, daily, and in pregnancy) datasets from National Survey of Drug Use and Health and US Census (income and ethnicity) and CDC Wonder population and birth data. Analysis was conducted in R. 266,950 were autistic of a population of 40,119,464 8-year-olds in 1994-2011. At national level after adjustment, daily cannabis use was significantly related to ASMR (β estimate = 4.37 (95%C.I. 4.06, 4.68), P < 2.2 × 10^-16) as was first pregnancy trimester cannabis exposure (β estimate = 0.12 (0.08, 0.16), P = 1.7 × 10^-12). At state level following adjustment for cannabis, cannabigerol (from β estimate = - 13.77 (- 19.41, 8.13), P = 1.8 × 10^-6) and Δ9-tetrahydrocannabinol (from β estimate = 1.96 (0.88-3.04), P = 4 × 10^-4) were significant. Geospatial state-level modelling showed exponential relationship between ASMR and Δ9-tetrahydrocannabinol and cannabigerol exposure. Exponential coefficients for the relationship between modelled ASMR and Δ9-tetrahydrocannabinol and cannabigerol exposure were 7.053 (6.39-7.71) and 185.334 (167.88-202.79; both P < 2.0 × 10^-7). E-values are an instrument related to the evidence for causality in observational studies. High E-values were noted. Dichotomized legal status was linked with elevated ASMR. Data show cannabis use is associated with ASMR, is powerful enough to affect overall trends, and persists after controlling for other major covariates. Cannabinoids are exponentially associated with ASMR. The cannabis-autism relationship satisfies criteria of causal inference.

Impact of cannabinoids on pregnancy, reproductive health and offspring outcomes

Cannabis is the most commonly used federally illegal drug in the United States and world, especially among people of reproductive age. In addition, the potency of cannabis products has increased significantly in the past decade. This is concerning because the available evidence suggests an adverse effect from cannabis exposure on male and female reproductive health. Exposure to cannabinoids may have differential impacts on female reproductive health across a woman's lifespan, from preconception to pregnancy, throughout lactation, and during menopause. Even more, cannabis use has been associated an adverse effect on fetal outcomes, and longer-term offspring health and developmental trajectories. Despite the prevalence of cannabis use, there is limited available evidence regarding its safety, especially in regard to reproductive health, pregnancy and lactation. The biological effects of cannabis are mediated by the endocannabinoid system and studies have reported the presence of cannabinoid receptors in the male and female reproductive tract, on sperm and the placenta, suggesting the endocannabinoid system plays a role in regulating reproduction. Cannabis use can impact male and female fertility and has been associated with altered reproductive hormones, menstrual cyclicity and semen parameters. Use of cannabis in males has also been associated with erectile dysfunction, abnormal spermatogenesis, and testicular atrophy. In females, cannabis use has been associated with infertility and abnormal embryo implantation and development. The main psychoactive component of cannabis, delta-9-tetrahydrocannabinol (THC), can also cross the placenta and has been detected in breastmilk. Maternal cannabis use during pregnancy and lactation has been associated with adverse effects including small for gestational age infants, preterm birth, fetal neurodevelopmental consequences, and impaired offspring sociobehavioral and cognitive development. The prevalence of cannabis use to alleviate menopausal symptoms has also increased despite the limited information on its benefits and safety. As cannabis use is on the rise, it is critical to understand its impact on reproductive health and offspring developmental outcomes. This is an understudied, but timely subject, with much needed information to guide healthcare providers and those interested in conceiving, or that are pregnant and lactating, as well as those at the end of their reproductive time span.

Geotemporospatial and causal inference epidemiological analysis of US survey and overview of cannabis, cannabidiol and cannabinoid genotoxicity in relation to congenital anomalies 2001–2015

Background

Cannabinoids including cannabidiol have recognized genotoxic activities but their significance has not been studied broadly epidemiologically across the teratological spectrum. We examined these issues including contextual space-time relationships and formal causal inferential analysis in USA.

Methods

State congenital anomaly (CA) rate (CAR) data was taken from the annual reports of the National Birth Defects Prevention Network 2001–2005 to 2011–2015. Substance abuse rates were from the National Survey of Drug Use and Health a nationally representative longitudinal survey of the non-institutionalized US population with 74.1% response rate. Drugs examined were cigarettes, monthly and binge alcohol, monthly cannabis and analgesic and cocaine abuse. Early termination of pregnancy for abortion (ETOPFA) rates were taken from the published literature. Cannabinoid concentrations were from Drug Enforcement Agency. Ethnicity and income data were from the US Census Bureau. Inverse probability weighted (IPW) regressions and geotemporospatial regressions conducted for selected CAs.

Results

Data on 18,328,529 births from an aggregated population of 2,377,483,589 for mid-year analyses 2005–2013 comprehending 12,611 CARs for 62 CAs was assembled and ETOPFA-corrected (ETOPFACAR) where appropriate. E-Values for ETOPFACARs by substance trends were elevated for THC (40 CAs), cannabis (35 CAs), tobacco (11 CAs), cannabidiol (8 CAs), monthly alcohol (5 CAs) and binge alcohol (2 CAs) with minimum E-Values descending from 16.55, 1.55x107, 555.10, 7.53x1019, 9.30 and 32.98. Cardiovascular, gastrointestinal, chromosomal, limb reductions, urinary, face and body wall CAs particularly affected. Highest v. lowest substance use quintile CAR prevalence ratios 2.84 (95%C.I. 2.44, 3.31), 4.85 (4.08, 5.77) and 1.92 (1.63, 2.27) and attributable fraction in exposed 0.28 (0.27, 0.28), 0.57 (0.51, 0.62) and 0.47 (0.38, 0.55) for tobacco, cannabis and cannabidiol. Small intestinal stenosis or atresia and obstructive genitourinary defect were studied in detail in lagged IPW pseudo-randomized causal regressions and spatiotemporal models confirmed the causal role of cannabinoids. Spatiotemporal predictive modelling demonstrated strongly sigmoidal non-linear cannabidiol dose-response power-function relationships (P = 2.83x10−60 and 1.61x10−71 respectively).

Conclusions

Data implicate cannabinoids including cannabidiol in a diverse spectrum of heritable CAs. Sigmoidal non-linear dose-response relationships are of grave concern.

These transgenerational genotoxic, epigenotoxic, chromosomal-toxic putatively causal teratogenic effects strongly indicate tight restrictions on community cannabinoid penetration.

Geospatiotemporal and causal inference study of cannabis and other drugs as risk factors for female breast cancer USA 2003-2017

Breast cancer (BC) is the commonest human cancer and its incidence (BC incidence, BCI) is rising worldwide. Whilst both tobacco and alcohol have been linked to BCI genotoxic cannabinoids have not been investigated. Age-adjusted state-based BCI 2003-2017 was taken from the Surveillance Epidemiology and End Results database of the Centers for Disease Control. Drug use from the National Survey of Drug Use and Health, response rate 74.1%. Median age, median household income and ethnicity were from US census. Inverse probability weighted (ipw) multivariable regression conducted in R. In bivariate analysis BCI was shown to be significantly linked with rising cannabis exposure {β-est. = 3.93 [95% confidence interval 2.99, 4.87], P = 1.10 × 10^-15}. At 8 years lag cigarettes:cannabis [β-est. = 2660 (2150.4, 3169.3), P = 4.60 × 10^-22] and cannabis:alcoholism [β-est. = 7010 (5461.6, 8558.4), P = 1.80 × 10^-17] were significant in ipw-panel regression. Terms including cannabidiol [CBD; β-est. = 16.16 (0.39, 31.93), P = 0.446] and cannabigerol [CBG; β-est. = 6.23 (2.06, 10.39), P = 0.0034] were significant in spatiotemporal models lagged 1:2 years, respectively. Cannabis-liberal paradigms had higher BCI [67.50 ± 0.26 v. 65.19 ± 0.21/100 000 (mean ± SEM), P = 1.87 × 10^-11; β-est. = 2.31 (1.65, 2.96), P = 9.09 × 10^-12]. 55/58 expected values >1.25 and 13/58 >100. Abortion was independently and causally significant in space-time models. Data show that exposure to cannabis and the cannabinoids Δ9-tetrahydrocannabinol, CBD, CBG and alcoholism fulfil quantitative causal criteria for BCI across space and time. Findings are robust to adjustment for age and several known sociodemographic, socio-economic and hormonal risk factors and establish cannabinoids as an additional risk factor class for breast carcinogenesis. BCI is higher under cannabis-liberal legal paradigms.

European epidemiological patterns of cannabis- and substance-related congenital cardiovascular anomalies: geospatiotemporal and causal inferential study

As prenatal and community cannabis exposures have recently been linked with congenital heart disease (CHD), it was of interest to explore these associations in Europe in a causal framework and space-time context. Congenital anomaly data from Eurocat, drug-use data from the European Monitoring Centre for Drugs and Drug Addiction, and income from the World Bank. Countries with rising daily cannabis use had in general higher congenital anomaly rates over time than those without (time: status interaction: β-Est. = 0.0267, P = 0.0059). At inverse probability-weighted panel regression, cannabis terms were positive and significant for CHD, severe CHD, atrial septal defect, ventricular septal defect, atrioventricular septal defect, patent ductus arteriosus, tetralogy of Fallot, vascular disruptions, double outlet right ventricle, transposition of the great vessels, hypoplastic right heart, and mitral valve anomalies from 1.75 × 10^-19, 4.20 × 10^-11, <2.2 × 10^-16, <2.2 × 10^-16, 1.58 × 10^-12, 4.30 × 10^-9, 4.36 × 10^-16, 3.50 × 10^-8, 5.35 × 10^-12, <2.2 × 10^-16, 5.65 × 10^-5 and 6.06 × 10^-10. At spatial regression, terms including cannabis were positive and significant for this same list of anomalies from 0.0038, 1.05 × 10^-10, 0.0215, 8.94 × 10^-6, 1.23 × 10^-5, 2.05 × 10^-5, 1.07 × 10^-6, 8.77 × 10^-5, 9.11 × 10^-6, 0.0001, 3.10 × 10^-7 and 2.17 × 10^-7. 92.6% and 75.2% of 149 E-value estimates and minimum E-values were in high zone >9; 100.0% and 98.7% >1.25. Data show many congenital cardiac anomalies exhibit strong bivariate relationships with metrics of cannabis exposure. Causal inferential modelling for the twelve anomalies selected demonstrated convincing evidence of robust relationships to cannabis which survived adjustment and fulfilled epidemiological criteria for causal relationships. Space-time regression was similarly confirmatory. Epigenomic pathways constitute viable potential mechanisms. Given exponential genotoxic dose-response effects, careful and astute control of cannabinoid penetration is indicated.

Cannabinoid and substance relationships of European congenital anomaly patterns: a space-time panel regression and causal inferential study

With reports from Australia, Canada, USA, Hawaii and Colorado documenting a link between cannabis and congenital anomalies (CAs), this relationship was investigated in Europe. Data on 90 CAs were accessed from Eurocat. Tobacco and alcohol consumption and median household income data were from the World Bank. Amphetamine, cocaine and last month and daily use of cannabis from the European Monitoring Centre for Drugs and Drug Addiction. Cannabis herb and resin Δ9-tetrahydrocannabinol concentrations were from published reports. Data were processed in R. Twelve thousand three hundred sixty CA rates were sourced across 16 nations of Europe. Nations with a higher or increasing rate of daily cannabis use had a 71.77% higher median CA rates than others [median ± interquartile range 2.13 (0.59, 6.30) v. 1.24 (0.15, 5.14)/10 000 live births (P = 4.74 × 10^-17; minimum E-value (mEV) = 1.52]. Eighty-nine out of 90 CAs in bivariate association and 74/90 CAs in additive panel inverse probability weighted space-time regression were cannabis related. In inverse probability weighted interactive panel models lagged to zero, two, four and six years, 76, 31, 50 and 29 CAs had elevated mEVs (< 2.46 × 10³⁹) for cannabis metrics. Cardiovascular, central nervous, gastrointestinal, genital, uronephrology, limb, face and chromosomalgenetic systems along with the multisystem VACTERL syndrome were particularly vulnerable targets. Data reveal that cannabis is related to many CAs and fulfil epidemiological criteria of causality. The triple convergence of rising cannabis use prevalence, intensity of daily use and Δ9-tetrahydrocannabinol concentration in herb and resin is powerfully implicated as a primary driver of European teratogenicity, confirming results from elsewhere.

Congenital anomaly epidemiological correlates of Δ8THC across USA 2003-16: panel regression and causal inferential study

Δ8-Tetrahydrocannabinol (Δ8THC) is marketed in many US states as 'legal weed'. Concerns exist relating to class-wide genotoxic cannabinoid effects. We conducted an epidemiological investigation of Δ8THC-related genotoxicity expressed as 57 congenital anomaly (CA) rates (CARs) in the USA. CARs were taken from the Centers for Disease Control, Atlanta, Georgia. Drug exposure data were taken from the National Survey of Drug Use and Health, with a response rate of 74.1%. Ethnicity and income data were taken from the US Census Bureau. National cannabinoid exposure was taken from Drug Enforcement Agency publications and multiplied by state cannabis use data to derive state-based estimates of Δ8THC exposure. At bivariate continuous analysis, Δ8THC was associated with 23 CAs on raw CA rates, 33 CARs after correction for early termination for anomaly estimates and 41 on a categorical analysis comparing the highest and lowest exposure quintiles. At inverse probability weighted multivariable additive and interactive models lagged to 0, 2 and 4 years, Δ8THC was linked with 39, 8, 4 and 9 CAs. Chromosomal, cardiovascular, gastrointestinal, genitourinary, limb, central nervous system (CNS) and face systems were particularly affected. The minimum E-values ranged to infinity. Both the number of anomalies implicated and the effect sizes demonstrated were much greater for Δ8THC than for tobacco and alcohol combined. Δ8THC appears epidemiologically to be more strongly associated with many CAs than for tobacco and alcohol and is consistent with a cannabinoid class genotoxic/epigenotoxic effect. Quantitative causality criteria were fulfilled, and causal relationships either for Δ8THC or for cannabinoid/s, for which it is a surrogate marker, may be in operation.

Vapor cannabis exposure generationally affects male reproductive functions in mice

This study was performed to examine whether vapor exposure to cannabis plant matter negatively impacts male reproductive functions and testis development in mice. Adult CD-1 male mice (F0) were exposed to air (control) or 200 mg of vaporized cannabis plant matter 3x/day over a 10 day period. Subsequently, F0 males were bred with drug naïve CD-1 females to generate F1 males, and F1 offspring were used to generate F2 males. Cannabis vapor exposure decreased sperm count and/or motility in F0 and F1 males and disrupted the progression of germ cell development, as morphometric analyses exhibited an abnormal distribution of the stages of spermatogenesis in F0 males. Although plasma levels of testosterone were not affected by cannabis exposure in any ages or generations of males, dysregulated steroidogenic enzymes, Cyp11a1 and Cyp19a1, were observed in F0 testis. In the neonatal testis from F1 males, while apoptosis was not altered, DNA damage and DNMT1, but not DNMT3A and DNMT3B, were increased in germ cells following cannabis exposure. In contrast, the alterations of DNA damage and DNMT1 expression were not observed in F2 neonatal males. These results suggest that cannabis vapor exposure generationally affects male reproductive functions, probably due to disruption of spermatogenesis in the developing testis.

Effects of marijuana on reproductive health: preconception and gestational effects

PURPOSE OF REVIEW

Recent widespread legalization changes have promoted the availability of marijuana and its increased potency and perceived safety. The limited evidence on reproductive and perinatal outcomes from marijuana exposure is enough to warrant concern and action. The objective of this review is to provide a current and relevant summary of the recent literature surrounding this topic.

RECENT FINDINGS

The available published studies on the effect of marijuana exposure on reproductive health and pregnancy outcomes are conflicting. Human studies are often observational or retrospective and confounded by self-report and polysubstance use. However, the current, limited evidence suggests that marijuana use adversely affects male and female reproductive health. Additionally, prenatal marijuana exposure has been reported to be associated with an increased risk of preterm birth and small for gestational age infants.

SUMMARY

With the increasing prevalence of marijuana use, there is an urgent need for evidence-driven recommendations and guidelines for couples interested in conception, affected by infertility or who are expecting. At this time, no amount of marijuana use during conception or pregnancy is known to be well tolerated and the limited available evidence suggests that the safest choice is to abstain.

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.

Canadian Cannabis Consumption and Patterns of Congenital Anomalies: An Ecological Geospatial Analysis

OBJECTIVES

Cannabis is a known teratogen. Data availability addressing both major congenital anomalies and cannabis use allowed us to explore their geospatial relationships.

METHODS

Data for the years 1998 to 2009 from Canada Health and Statistics Canada was analyzed in R. Maps have been drawn and odds ratios, principal component analysis, correlation matrices, least squares regression and geospatial regression analyses have been conducted using the R packages base, dplyr, epiR, psych, ggplot2, colorplaner and the spml and spreml functions from package splm.

RESULTS

Mapping showed cannabis use was more common in the northern Territories of Canada in the Second National Survey of Cannabis Use 2018. Total congenital anomalies, all cardiovascular defects, orofacial clefts, Downs syndrome and gastroschisis were all found to be more common in these same regions and rose as a function of cannabis exposure. When Canada was dichotomized into high and low cannabis use zones by Provinces v Territories the Territories had a higher rate of total congenital anomalies 450.026 v 390.413 (O.R. = 1.16 95%C.I. 1.08-1.25, P = 0.000058; attributable fraction in exposed 13.25%, 95%C.I. 7.04-19.04%). In geospatial analysis in a spreml spatial error model cannabis was significant both alone as a main effect (P < 2.0 × 10) and in all its first and second order interactions with both tobacco and opioids from P < 2.0 × 10.

CONCLUSION

These results show that the northern Territories of Canada share a higher rate of cannabis use together with elevated rates of total congenital anomalies, all cardiovascular defects, Down's syndrome and gastroschisis. This is the second report of a significant association between cannabis use and both total defects and all cardiovascular anomalies and the fourth published report of a link with Downs syndrome and thereby direct major genotoxicity. The correlative relationships described in this paper are confounded by many features of social disadvantage in Canada's northern territories. However, in the context of a similar broad spectrum of defects described both in animals and in epidemiological reports from Hawaii, Colorado, USA and Australia they are cause for particular concern and indicate further research.

Gastroschisis in Ontario, Canada: 2012-2018

BACKGROUND

Gastroschisis is a congenital anomaly of the abdomen in which the intestines are found outside of the body at birth. While no clear causative factors have been identified, it is strongly associated with young maternal age. Other reported associations include low maternal socioeconomic status, low maternal body mass index (BMI), and smoking.

METHODS

This is a retrospective review of epidemiologic data relating to cases of gastroschisis in Ontario from 2012-2018 in the Better Outcomes Registry & Network (BORN) Ontario database, which is the province's prescribed maternal-newborn registry. We describe the epidemiology of gastroschisis in Ontario with respect to birth prevalence, maternal age, health, exposures, and geography.

RESULTS

The birth prevalence of gastroschisis is 2.31 cases/10,000 births. There was no apparent change in birth prevalence over the study period and there was no difference between male and female infants. Gastroschisis was associated with younger maternal ages and was inversely correlated with maternal BMI. Gastroschisis was associated with first completed pregnancy. Maternal diabetes was associated with a lower birth prevalence of gastroschisis than average. Mothers of babies with gastroschsis were more likely to report use of tobacco, alcohol, and drugs during pregnancy than those without gastroschisis, with marijuana use showing the largest increase in birth prevalence of gastroschisis. Mothers living in rural areas were more likely to have a baby with gastroschisis than those in urban centers, even after controlling for maternal age.

CONCLUSIONS

This Ontario registry study reveals that mothers with babies with gastroschisis are more likely to be young and thin, live in rural areas, and report prenatal smoking, alcohol use, and drug use than women whose pregnancies do not have gastroschsis.

Broad Spectrum epidemiological contribution of cannabis and other substances to the teratological profile of northern New South Wales: geospatial and causal inference analysis

Background

Whilst cannabis commercialization is occurring rapidly guided by highly individualistic public narratives, evidence that all congenital anomalies (CA) increase alongside cannabis use in Canada, a link with 21 CA’s in Hawaii, and rising CA’s in Colorado indicate that transgenerational effects can be significant and impact public health. It was therefore important to study Northern New South Wales (NNSW) where cannabis use is high.

Methods

Design: Cohort. 2008–2015. Setting: NNSW and Queensland (QLD), Australia. Participants. Whole populations. Exposures. Tobacco, alcohol, cannabis. Source: National Drug Strategy Household Surveys 2010, 2013. Main Outcomes. CA Rates. NNSW-QLD comparisons. Geospatial and causal regression.

Results

Cardiovascular, respiratory and gastrointestinal anomalies rose with falling tobacco and alcohol but rising cannabis use rates across Queensland. Maternal age NNSW-QLD was not different (2008–2015: 4265/22084 v. 96,473/490514 > 35 years/total, Chi.Sq. = 1.687, P = 0.194). A higher rate of NNSW cannabis-related than cannabis-unrelated defects occurred (prevalence ratio (PR) = 2.13, 95%C.I. 1.80–2.52, P = 3.24 × 10^− 19). CA’s rose more potently with rising cannabis than with rising tobacco or alcohol use. Exomphalos and gastroschisis had the highest NNSW:QLD PR (6.29(2.94–13.48) and 5.85(3.54–9.67)) and attributable fraction in the exposed (84.11%(65.95–92.58%) and 82.91%(71.75–89.66%), P = 2.83 × 10^− 8 and P = 5.62 × 10^− 15). In multivariable geospatial models cannabis was significantly linked with cardiovascular (atrial septal defect, ventricular septal defect, tetralogy of Fallot, patent ductus arteriosus), genetic (chromosomal defects, Downs syndrome), gastrointestinal (small intestinal atresia), body wall (gastroschisis, diaphragmatic hernia) and other (hypospadias) (AVTPCDSGDH) CA’s. In linear modelling cannabis use was significantly linked with anal stenosis, congenital hydrocephalus and Turner syndrome (ACT) and was significantly linked in borderline significant models (model P < 0.1) with microtia, microphthalmia, and transposition of the great vessels. At robust and mixed effects inverse probability weighted multivariable regression cannabis was related to 18 defects. 16/17 E-Values in spatial models were > 1.25 ranging up to 5.2 × 10¹³ making uncontrolled confounding unlikely.

Conclusions

These results suggest that population level CA’s react more strongly to small rises in cannabis use than tobacco or alcohol; cardiovascular, chromosomal, body wall and gastrointestinal CA’s rise significantly with small increases in cannabis use; that cannabis is a bivariate correlate of AVTPCDSGDH and ACT anomalies, is robust to adjustment for other substances; and is causal.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s40360-020-00450-1.

Prevalence and risk factors for congenital diaphragmatic hernia: A global view

PURPOSE

To determine the global prevalence for congenital diaphragmatic hernia (CDH) and identify CDH-related risk factors.

METHODS

Using a defined strategy, a systematic review of the literature was conducted according to PRISMA guidelines, searching for population-based epidemiological studies to evaluate the prevalence of CDH globally and per country. Studies containing overlapping populations or timeframes were excluded. CDH-related risk factors were calculated by meta-analysis using RevMan5.3 and expressed as risk ratio and 95% confidence interval.

RESULTS

Prevalence: Of 8230 abstracts screened, 30 full-text articles published between 1980 and 2019 were included. The overall prevalence of CDH was 2.3 in 10,000 births (16,710 CDH babies in 73,663,758 livebirths).

RISK FACTORS

From 9 studies we found that male sex [RR 1.38 (1.05-1.80), p=0.02] and maternal age >35 years [RR 1.69 (1.26-2.25), p=0.0004] were associated with CDH. Conversely, maternal black ethnicity resulted as a protective factor [RR 0.82 (0.77-0.89, p<0.00001].

CONCLUSION

This study reveals that there is a worldwide paucity of population-based studies, and those studies that report on prevalence and risk factors come from a small number of countries. The prevalence of CDH varies within and across geographical world regions. The main risk factors for CDH identified are male sex and older maternal age. More epidemiological studies, involving more world regions, are needed to identify possible strategies to help strengthen our understanding of the risk factors, provide clinicians with the tools necessary for prenatal and postnatal counseling, and inform policy makers on how to strategize CDH care in different parts of the world.

TYPE OF STUDY

Systematic review and meta-analysis.

LEVEL OF EVIDENCE

Level III.

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 Role of Adverse Childhood Experiences on Perinatal Substance Use Behaviour in KwaZulu-Natal Province, South Africa

The role of risky sexual behaviour has been widely investigated across the sub-Saharan African HIV hyperendemic setting, with few studies having focused on the behaviour attributed to the deep-rooted, neurodevelopmentally-driven adverse childhood experiences (ACE) that sustain the endemic. We investigated the role of ACE on perinatal substance use outcomes in KwaZulu-Natal Province, South Africa, with 223 women being interviewed within one-week post-partum at a general hospital. Our secondary outcome was the occurrence of preterm birth delivery, which is understood to be linked to ACE. Study results suggest that the most common perinatal substance use was alcohol (n = 27, 12.11%), followed by tobacco (n = 18, 8.07%), with the prevalence of preterm birth delivery being 8.97% (n = 20, 8.97%). Regression analyses indicated increased ACE being significantly associated with perinatal alcohol (aOR = 1.45, 95% CI 1.22-1.72), tobacco use (aOR = 1.56, 95% CI 1.23-1.97) and preterm birth delivery (aOR = 1.21, 95% CI 1.03-1.43), independent of socio-economic status. When the model was further adjusted by HIV status, suppressed viral load was more significantly associated with lower odds of preterm birth delivery (aOR = 0.06, 95% CI: 0.01-0.24) than an unsuppressed status. Risk-behaviour reduction strategies should address the role of ACE on substance use and viral load, and hence possibly ART adherence, in HIV hyperendemic settings.

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.

Marijuana Use in Pregnancy: A Review

Importance

Marijuana is the most commonly used dependent substance in pregnancy. The main active chemical of marijuana (delta-9-tetrahydrocannabinol [THC]) readily crosses the placenta, and cannabinoid receptors have been identified in fetal brain and placenta. As a result, prenatal marijuana use could potentially have detrimental impact on fetal development.

Objective

This review aims to summarize the existing literature and current recommendations for marijuana use while pregnant or lactating.

Evidence Acquisition

A PubMed literature search using the following terms was performed to gather relevant data: "cannabis," "cannabinoids," "marijuana," "fetal outcomes," "perinatal outcomes," "pregnancy," "lactation."

Results

Available studies on marijuana exposure in pregnancy were reviewed and support some degree of developmental disruption, including an increased risk of fetal growth restriction and adverse neurodevelopmental consequences. However, much of the existing prenatal marijuana research was performed in the 1980s, when quantities of THC were lower and the frequency of use was less. Additionally, most human studies are also limited and conflicting as most studies have been observational or retrospective, relying primarily on patient self-report and confounded by polysubstance abuse and small sample sizes, precluding determination of a causal effect specific for marijuana. Given the paucity of evidence, it is currently recommended to avoid using marijuana while pregnant or when breastfeeding.

Conclusion and Relevance

There is a critical need for research on effects in pregnancy using present-day THC doses. Once the adverse perinatal effects of marijuana exposure are identified and well characterized, patient education and antenatal surveillance can be developed to predict and mitigate its impact on maternal and fetal health.

Maternal occupational exposure to solvents and gastroschisis in offspring - National Birth Defects Prevention Study 1997-2011

Objectives

The aim of this study was to assess the association between maternal occupational exposure to solvents and gastroschisis in offspring.

Methods

We used data from the National Birth Defects Prevention Study, a large population-based case-control study of major birth defects conducted in 10 US states from 1997 to 2011. Infants with gastroschisis were ascertained by active birth defects surveillance systems. Control infants without major birth defects were selected from vital records or birth hospital records. Self-reported maternal occupational histories were collected by telephone interview. Industrial hygienists reviewed this information to estimate exposure to aromatic, chlorinated and petroleum-based solvents from 1 month before conception through the first trimester of pregnancy. Cumulative exposure to solvents was estimated for the same period accounting for estimated exposure intensity and frequency, job duration and hours worked per week. ORs and 95% CIs were estimated to assess the association between exposure to any solvents or solvent classes, and gastroschisis risk.

Results

Among 879 cases and 7817 controls, the overall prevalence of periconceptional solvent exposure was 7.3% and 7.4%, respectively. Exposure to any solvent versus no exposure to solvents was not associated with gastroschisis after adjusting for maternal age (OR 1.00, 95% CI 0.75 to 1.32), nor was an association noted for solvent classes. There was no exposure-response relationship between estimated cumulative solvent exposure and gastroschisis after adjusting for maternal age.

Conclusion

Our study found no association between maternal occupational solvent exposure and gastroschisis in offspring. Further research is needed to understand risk factors for gastroschisis.

Cannabis Consumption Patterns Explain the East-West Gradient in Canadian Neural Tube Defect Incidence: An Ecological Study

While a known link between prenatal cannabis exposure and anencephaly exists, the relationship of prenatal cannabis exposure with neural tube defects (NTDs) generally has not been defined. Published data from Canada Health and Statistics Canada were used to assess this relationship. Both cannabis use and NTDs were shown to follow an east-west and north-south gradient. Last year cannabis consumption was significantly associated (P < .0001; cannabis use–time interaction P < .0001). These results were confirmed when estimates of termination for anomaly were used. Canada Health population data allowed the calculation of an NTD odds ratio) of 1.27 (95% confidence interval = 1.19-1.37; P < 10⁻¹¹) for high-risk provinces versus the remainder with an attributable fraction in exposed populations of 16.52% (95% confidence interval = 12.22-20.62). Data show a robust positive statistical association between cannabis consumption as both a qualitative and quantitative variable and NTDs on a background of declining NTD incidence. In the context of multiple mechanistic pathways these strong statistical findings implicate causal mechanisms.

Cannabis Teratology Explains Current Patterns of Coloradan Congenital Defects: The Contribution of Increased Cannabinoid Exposure to Rising Teratological Trends

Rising Δ9-tetrahydrocannabinol concentrations in modern cannabis invites investigation of the teratological implications of prenatal cannabis exposure. Data from Colorado Responds to Children with Special Needs (CRCSN), National Survey of Drug Use and Health, and Drug Enforcement Agency was analyzed. Seven, 40, and 2 defects were rising, flat, and falling, respectively, and 10/12 summary indices rose. Atrial septal defect, spina bifida, microcephalus, Down's syndrome, ventricular septal defect, and patent ductus arteriosus rose, and along with central nervous system, cardiovascular, genitourinary, respiratory, chromosomal, and musculoskeletal defects rose 5 to 37 times faster than the birth rate (3.3%) to generate an excess of 11 753 (22%) major anomalies. Cannabis was the only drug whose use grew from 2000 to 2014 while pain relievers, cocaine, alcohol, and tobacco did not. The correlation of cannabis use with major defects in 2014 (2019 dataset) was R = .77, P = .0011. Multiple cannabinoids were linked with summary measures of congenital anomalies and were robust to multivariate adjustment.

Impacts of cannabinoid epigenetics on human development: reflections on Murphy et. al. 'cannabinoid exposure and altered DNA methylation in rat and human sperm' epigenetics 2018; 13: 1208-1221

Recent data from the Kollins lab (‘Cannabinoid exposure and altered DNA methylation in rat and human sperm’ Epigenetics 2018; 13: 1208–1221) indicated epigenetic effects of cannabis use on sperm in man parallel those in rats and showed substantial shifts in both hypo- and hyper-DNA methylation with the latter predominating. This provides one likely mechanism for the transgenerational transmission of epigenomic instability with sperm as the vector. It therefore contributes important pathophysiological insights into the probable mechanisms underlying the epidemiology of prenatal cannabis exposure potentially explaining diverse features of cannabis-related teratology including effects on the neuraxis, cardiovasculature, immune stimulation, secondary genomic instability and carcinogenesis related to both adult and pediatric cancers. The potentially inheritable and therefore multigenerational nature of these defects needs to be carefully considered in the light of recent teratological and neurobehavioural trends in diverse jurisdictions such as the USA nationally, Hawaii, Colorado, Canada, France and Australia, particularly relating to mental retardation, age-related morbidity and oncogenesis including inheritable cancerogenesis. Increasing demonstrations that the epigenome can respond directly and in real time and retain memories of environmental exposures of many kinds implies that the genome-epigenome is much more sensitive to environmental toxicants than has been generally realized. Issues of long-term multigenerational inheritance amplify these concerns. Further research particularly on the epigenomic toxicology of many cannabinoids is also required.

The impact of maternal smoking during pregnancy on childhood asthma: adjusted for exposure misclassification; results from the National Health and Nutrition Examination Survey, 2011-2012

PURPOSE

We sought to examine the association between childhood asthma and self-reported maternal smoking during pregnancy (MSDP) after adjusting for a range of exposure misclassification scenarios using a Bayesian approach that incorporated exposure misclassification probability estimates from the literature.

METHODS

Self-reported MSDP and asthma data were extracted from National Health and Nutrition Examination Survey 2011-2012. The association between self-reported MSDP and asthma was adjusted for exposure misclassification using a Bayesian bias model approach.

RESULTS

We included 3074 subjects who were 1-15 years of age, including 492 asthma cases. The mean (SD) of age of the participants was 8.5 (4.1) and 7.1 (4.2) years and the number (percentage) of female was 205 (42%) and 1314 (51%) among asthmatic and nonasthmatic groups, respectively. The odds ratio (OR) for the association between self-reported MSDP and asthma in logistic regression adjusted for confounders was 1.28 (95% confidence interval: 0.92, 1.77). In a Bayesian analysis that adjusted for exposure misclassification using external data, we found different ORs between MSDP and asthma by applying different priors (posterior ORs 0.90 [95% credible interval {CRI}: 0.47, 1.60] to 3.05 [95% CRI: 1.73, 5.53] in differential and 1.22 [CRI 95%: 0.62, 2.25] to 1.60 CRI: 1.18, 2.19) in nondifferential misclassification settings.

CONCLUSIONS

Given the assumptions and the accuracy of the bias model, the estimated effect of MSDP on asthma after adjusting for misclassification was strengthened in many scenarios.

Possible etiologies of increased incidence of gastroschisis

PURPOSE

Gastroschisis incidence has increased over the past decade nationally and in Hawaii. Pesticides have been implicated as potential causative factors for gastroschisis, and use of restricted use pesticides (RUPs) is widespread in Hawaii. This study was conducted to characterize gastroschisis cases in Hawaii and determine whether RUP application correlates with gastroschisis incidence.

METHODS

Gastroschisis patients treated in Hawaii between September, 2008 and August, 2015 were mapped by zip code along with RUP use. Spatial analysis software was used to identify patients' homes located within the pesticide application zone and agricultural land use areas.

RESULTS

71 gastroschisis cases were identified. 2.8% of patients were from Kauai, 64.8% from Oahu, 16.9% from Hawaii, 14.1% from Maui, and 1.4% from Molokai. RUPs have been used on all of these islands. 78.9% of patients lived in zip codes overlapping agricultural land use areas. 85.9% of patients shared zip codes with RUP-use areas.

CONCLUSION

The majority of gastroschisis patients were from RUP-use areas, supporting the idea that pesticides may contribute to the development of gastroschisis, although limited data on specific releases make it difficult to apply these findings. As more RUP-use data become available to the public, these important research questions can be investigated further.

Administrative Claims Data Versus Augmented Pregnancy Data for the Study of Pharmaceutical Treatments in Pregnancy

Purpose of Review

Administrative claims databases, which collect reimbursement-related information generated from healthcare encounters, are increasingly used to evaluate medication safety in pregnancy. We reviewed the strengths and limitations of claims-only databases and how other data sources may be used to improve the accuracy and completeness of information critical for studying medication safety in pregnancy.

Recent Findings

Research on medication safety in pregnancy requires information on pregnancy episodes, mother-infant linkage, medication exposure, gestational age, maternal and birth outcomes, confounding factors, and (in some studies) long-term follow-up data. Claims data reliably identifies live births and possibly other pregnancies. It allows mother-infant linkage and has prospectively collected prescription medication information. Its diagnosis and procedure information allows estimation of gestational age. It captures maternal medical conditions but generally has incomplete data on reproductive and lifestyle factors. It has information on certain, typically short-term maternal and infant outcomes that may require chart review confirmation. Other data sources including electronic health records and birth registries can augment claims data or be analyzed alone. Interviews, surveys, or biological samples provide additional information. Nationwide and regional birth and pregnancy registries, such as those in several European and North American countries, generally contain more complete information essential for pregnancy research compared to claims-only databases.

Summary

Claims data offers several advantages in medication safety in pregnancy research. Its limitations can be partially addressed by linking it with other data sources or supplementing with primary data collection. Rigorous assessment of data quality and completeness is recommended regardless of data sources.