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Association Between Self-reported Prenatal Cannabis Use and Maternal, Perinatal, and Neonatal Outcomes

Educational Objective
To understand maternal risk factors for adverse birth outcomes.
1 Credit CME
Key Points

Question  Is there an association between prenatal cannabis exposure and maternal, perinatal, and neonatal outcomes?

Findings  In this retrospective cohort study that included 661 617 pregnancies and 9427 reported cannabis users, the rate of preterm birth among reported cannabis users was 12% vs 6% in nonusers, a statistically significant difference.

Meaning  Reported cannabis use in pregnancy was associated with significant increases in the rate of preterm birth following adjustment for confounding.


Importance  Recent evidence suggests that cannabis use during pregnancy is increasing, although population-based data about perinatal outcomes following in utero exposure remain limited.

Objective  To assess whether there are associations between self-reported prenatal cannabis use and adverse maternal and perinatal outcomes.

Design, Setting, and Participants  Population-based retrospective cohort study covering live births and stillbirths among women aged 15 years and older in Ontario, Canada, between April 2012 and December 2017.

Exposures  Self-reported cannabis exposure in pregnancy was ascertained through routine perinatal care.

Main Outcomes and Measures  The primary outcome was preterm birth before 37 weeks’ gestation. Indicators were defined for birth occurring at 34 to 36 6/7 weeks’ gestation (late preterm), 32 to 33 6/7 weeks’ gestation, 28 to 31 6/7 weeks’ gestation, and less than 28 weeks’ gestation (very preterm birth). Ten secondary outcomes were examined including small for gestational age, placental abruption, transfer to neonatal intensive care, and 5-minute Apgar score. Coarsened exact matching techniques and Poisson regression models were used to estimate the risk difference (RD) and relative risk (RR) of outcomes associated with cannabis exposure and control for confounding.

Results  In a cohort of 661 617 women, the mean gestational age was 39.3 weeks and 51% of infants were male. Mothers had a mean age of 30.4 years and 9427 (1.4%) reported cannabis use during pregnancy. Imbalance in measured maternal obstetrical and sociodemographic characteristics between reported cannabis users and nonusers was attenuated using matching, yielding a sample of 5639 reported users and 92 873 nonusers. The crude rate of preterm birth less than 37 weeks’ gestation was 6.1% among women who did not report cannabis use and 12.0% among those reporting use in the unmatched cohort (RD, 5.88% [95% CI, 5.22%-6.54%]). In the matched cohort, reported cannabis exposure was significantly associated with an RD of 2.98% (95% CI, 2.63%-3.34%) and an RR of 1.41 (95% CI, 1.36-1.47) for preterm birth. Compared with no reported use, cannabis exposure was significantly associated with greater frequency of small for gestational age (third percentile, 6.1% vs 4.0%; RR, 1.53 [95% CI, 1.45-1.61]), placental abruption (1.6% vs 0.9%; RR, 1.72 [95% CI, 1.54-1.92]), transfer to neonatal intensive care (19.3% vs 13.8%; RR, 1.40 [95% CI, 1.36-1.44]), and 5-minute Apgar score less than 4 (1.1% vs 0.9%; RR, 1.28 [95% CI, 1.13-1.45]).

Conclusions and Relevance  Among pregnant women in Ontario, Canada, reported cannabis use was significantly associated with an increased risk of preterm birth. Findings may be limited by residual confounding.

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CME Disclosure Statement: Unless noted, all individuals in control of content reported no relevant financial relationships. If applicable, all relevant financial relationships have been mitigated.

Article Information

Corresponding Author: Daniel J. Corsi, PhD, OMNI Research Group, Centre for Practice Changing Research, Ottawa Hospital Research Institute, L1242, 501 Smyth Rd, PO Box 241, Ottawa, ON K1H 8L6, Canada (

Accepted for Publication: June 3, 2019.

Published Online: June 18, 2019. doi:10.1001/jama.2019.8734

Author Contributions: Dr Corsi had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Corsi, Hsu, El-Chaar, Fell, Walker.

Acquisition, analysis, or interpretation of data: Corsi, Walsh, Weiss, Hawken, Fell, Walker.

Drafting of the manuscript: Corsi, Hsu, Fell, Walker.

Critical revision of the manuscript for important intellectual content: Corsi, Walsh, Weiss, El-Chaar, Hawken, Fell, Walker.

Statistical analysis: Corsi, Walsh, Weiss, Hawken, Fell.

Obtained funding: Hsu, El-Chaar.

Administrative, technical, or material support: Hsu, El-Chaar, Walker.

Supervision: Corsi, Walker.

Conflict of Interest Disclosures: Drs Corsi, El-Chaar, Hsu, and Walker reported receiving grants from the Canadian Institutes of Health Research. No other disclosures were reported.

Funding/Support: This study was funded by the Canadian Institutes of Health Research.

Role of the Funder/Sponsor: The funding source had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and the decision to submit the manuscript for publication.

Data Sharing Statement: Requests for data access can be made to BORN Ontario at

Young-Wolff  KC, Tucker  L-Y, Alexeeff  S,  et al.  Trends in self-reported and biochemically tested marijuana use among pregnant females in California from 2009-2016.  JAMA. 2017;318(24):2490-2491. doi:10.1001/jama.2017.17225PubMedGoogle ScholarCrossref
Government of Canada. Canadian Tobacco, Alcohol and Drugs Survey (CTADS): summary of results for 2017. Accessed June 7, 2019.
Corsi  DJ, Hsu  H, Weiss  D, Fell  DB, Walker  M.  Trends and correlates of cannabis use in pregnancy: a population-based study in Ontario, Canada from 2012 to 2017.  Can J Public Health. 2019;110(1):76-84. doi:10.17269/s41997-018-0148-0PubMedGoogle ScholarCrossref
Brown  QL, Sarvet  AL, Shmulewitz  D, Martins  SS, Wall  MM, Hasin  DS.  Trends in marijuana use among pregnant and nonpregnant reproductive-aged women, 2002-2014.  JAMA. 2017;317(2):207-209. doi:10.1001/jama.2016.17383PubMedGoogle ScholarCrossref
Cerdá  M, Wall  M, Feng  T,  et al.  Association of state recreational marijuana laws with adolescent marijuana use.  JAMA Pediatr. 2017;171(2):142-149. doi:10.1001/jamapediatrics.2016.3624PubMedGoogle ScholarCrossref
Richardson  KA, Hester  AK, McLemore  GL.  Prenatal cannabis exposure: the “first hit” to the endocannabinoid system.  Neurotoxicol Teratol. 2016;58:5-14. doi:10.1016/ ScholarCrossref
Correa  F, Wolfson  ML, Valchi  P, Aisemberg  J, Franchi  AM.  Endocannabinoid system and pregnancy.  Reproduction. 2016;152(6):R191-R200. doi:10.1530/REP-16-0167PubMedGoogle ScholarCrossref
Varner  MW, Silver  RM, Rowland Hogue  CJ,  et al; Eunice Kennedy Shriver National Institute of Child Health and Human Development Stillbirth Collaborative Research Network.  Association between stillbirth and illicit drug use and smoking during pregnancy.  Obstet Gynecol. 2014;123(1):113-125. doi:10.1097/AOG.0000000000000052PubMedGoogle ScholarCrossref
Fergusson  DM, Horwood  LJ, Northstone  K; ALSPAC Study Team; Avon Longitudinal Study of Pregnancy and Childhood.  Maternal use of cannabis and pregnancy outcome.  BJOG. 2002;109(1):21-27. doi:10.1111/j.1471-0528.2002.01020.xPubMedGoogle ScholarCrossref
Hayatbakhsh  MR, Flenady  VJ, Gibbons  KS,  et al.  Birth outcomes associated with cannabis use before and during pregnancy.  Pediatr Res. 2012;71(2):215-219. doi:10.1038/pr.2011.25PubMedGoogle ScholarCrossref
Gunn  JKL, Rosales  CB, Center  KE,  et al.  Prenatal exposure to cannabis and maternal and child health outcomes: a systematic review and meta-analysis.  BMJ Open. 2016;6(4):e009986. doi:10.1136/bmjopen-2015-009986PubMedGoogle ScholarCrossref
Conner  SN, Bedell  V, Lipsey  K, Macones  GA, Cahill  AG, Tuuli  MG.  Maternal marijuana use and adverse neonatal outcomes: a systematic review and meta-analysis.  Obstet Gynecol. 2016;128(4):713-723. doi:10.1097/AOG.0000000000001649PubMedGoogle ScholarCrossref
Dunn  S, Bottomley  J, Ali  A, Walker  M.  2008 Niday Perinatal Database quality audit: report of a quality assurance project.  Chronic Dis Inj Can. 2011;32(1):32-42.PubMedGoogle Scholar
Public Health Agency of Canada.  Perinatal Health Indicators for Canada 2013: A Report of the Canadian Perinatal Surveillance System. Ottawa, Ontario, Canada: Public Health Agency of Canada; 2013.
Johnston  KM, Gooch  K, Korol  E,  et al.  The economic burden of prematurity in Canada.  BMC Pediatr. 2014;14:93. doi:10.1186/1471-2431-14-93PubMedGoogle ScholarCrossref
Apgar  V.  A proposal for a new method of evaluation of the newborn infant: originally published in July 1953, volume 32, pages 250-259.  Anesth Analg. 2015;120(5):1056-1059. doi:10.1213/ANE.0b013e31829bdc5cPubMedGoogle ScholarCrossref
Statistics Canada.  Postal Code Conversion File Plus (PCCF+) Version 6D. Ottawa, Ontario, Canada: Statistics Canada; 2016.
Institute of Medicine; National Research Council Committee to Reexamine IOM Pregnancy Weight Guidelines. In: Rasmussen  KM, Yaktine  AL, eds;  Weight Gain During Pregnancy: Reexamining the Guidelines. Washington, DC: National Academy of Sciences; 2009.
Austin  PC.  Balance diagnostics for comparing the distribution of baseline covariates between treatment groups in propensity-score matched samples.  Stat Med. 2009;28(25):3083-3107. doi:10.1002/sim.3697PubMedGoogle ScholarCrossref
Ho  DE, Imai  K, King  G, Stuart  EA.  Matching as nonparametric preprocessing for reducing model dependence in parametric causal inference.  Polit Anal. 2007;15(3):199-236. doi:10.1093/pan/mpl013Google ScholarCrossref
Iacus  SM, King  G, Porro  G.  Causal inference without balance checking: coarsened exact matching.  Polit Anal. 2012;20(1):1-24. doi:10.1093/pan/mpr013Google ScholarCrossref
Iacus  SM, King  G, Porro  G.  Multivariate matching methods that are monotonic imbalance bounding.  J Am Stat Assoc. 2011;106(493):345-361. doi:10.1198/jasa.2011.tm09599Google ScholarCrossref
Zeileis  A.  Econometric computing with HC and HAC covariance matrix estimators.  J Stat Softw. 2004;11(10):1-17. doi:10.18637/jss.v011.i10Google ScholarCrossref
MacKinnon  JG, White  H.  Some heteroskedasticity-consistent covariance matrix estimators with improved finite sample properties.  J Econom. 1985;29(3):305-325. doi:10.1016/0304-4076(85)90158-7Google ScholarCrossref
Barros  AJ, Hirakata  VN.  Alternatives for logistic regression in cross-sectional studies: an empirical comparison of models that directly estimate the prevalence ratio.  BMC Med Res Methodol. 2003;3(1):21. doi:10.1186/1471-2288-3-21PubMedGoogle ScholarCrossref
Kramer  MS.  The epidemiology of adverse pregnancy outcomes: an overview.  J Nutr. 2003;133(5)(suppl 2):1592S-1596S. doi:10.1093/jn/133.5.1592SPubMedGoogle ScholarCrossref
Petrangelo  A, Czuzoj-Shulman  N, Balayla  J, Abenhaim  HA.  Cannabis abuse or dependence during pregnancy: a population-based cohort study on 12 million births.  J Obstet Gynaecol Can. 2019;41(5):623-630. doi:10.1016/j.jogc.2018.09.009PubMedGoogle ScholarCrossref
Yang  T, Walker  MC, Krewski  D,  et al.  Maternal characteristics associated with pregnancy exposure to FDA category C, D, and X drugs in a Canadian population.  Pharmacoepidemiol Drug Saf. 2008;17(3):270-277. doi:10.1002/pds.1538PubMedGoogle ScholarCrossref
England  L, Zhang  J.  Smoking and risk of preeclampsia: a systematic review.  Front Biosci. 2007;12:2471-2483. doi:10.2741/2248PubMedGoogle ScholarCrossref
Rajesh  M, Mukhopadhyay  P, Bátkai  S,  et al.  Cannabidiol attenuates cardiac dysfunction, oxidative stress, fibrosis, and inflammatory and cell death signaling pathways in diabetic cardiomyopathy.  J Am Coll Cardiol. 2010;56(25):2115-2125. doi:10.1016/j.jacc.2010.07.033PubMedGoogle ScholarCrossref
Weiss  L, Zeira  M, Reich  S,  et al.  Cannabidiol lowers incidence of diabetes in non-obese diabetic mice.  Autoimmunity. 2006;39(2):143-151. doi:10.1080/08916930500356674PubMedGoogle ScholarCrossref
Booz  GW.  Cannabidiol as an emergent therapeutic strategy for lessening the impact of inflammation on oxidative stress.  Free Radic Biol Med. 2011;51(5):1054-1061. doi:10.1016/j.freeradbiomed.2011.01.007PubMedGoogle ScholarCrossref
Cook  JL, Green  CR, de la Ronde  S,  et al.  Screening and management of substance use in pregnancy: a review.  J Obstet Gynaecol Can. 2017;39(10):897-905. doi:10.1016/j.jogc.2017.07.017PubMedGoogle ScholarCrossref
Stone  R.  Pregnant women and substance use: fear, stigma, and barriers to care.  Health Justice. 2015;3(1):2. doi:10.1186/s40352-015-0015-5Google ScholarCrossref
Yonkers  KA, Howell  HB, Gotman  N, Rounsaville  BJ.  Self-report of illicit substance use versus urine toxicology results from at-risk pregnant women.  J Subst Use. 2011;16(5):372-389. doi:10.3109/14659891003721133PubMedGoogle ScholarCrossref
Johnson  T, Fendrich  M.  Modeling sources of self-report bias in a survey of drug use epidemiology.  Ann Epidemiol. 2005;15(5):381-389. doi:10.1016/j.annepidem.2004.09.004PubMedGoogle ScholarCrossref
El Marroun  H, Tiemeier  H, Jaddoe  VW,  et al.  Agreement between maternal cannabis use during pregnancy according to self-report and urinalysis in a population-based cohort: the Generation R Study.  Eur Addict Res. 2011;17(1):37-43. doi:10.1159/000320550PubMedGoogle ScholarCrossref
Markovic  N, Ness  RB, Cefilli  D, Grisso  JA, Stahmer  S, Shaw  LM.  Substance use measures among women in early pregnancy.  Am J Obstet Gynecol. 2000;183(3):627-632. doi:10.1067/mob.2000.106450PubMedGoogle ScholarCrossref
Johansson  E, Halldin  MM.  Urinary excretion half-life of delta 1-tetrahydrocannabinol-7-oic acid in heavy marijuana users after smoking.  J Anal Toxicol. 1989;13(4):218-223. doi:10.1093/jat/13.4.218PubMedGoogle ScholarCrossref
Sterne  JA, White  IR, Carlin  JB,  et al.  Multiple imputation for missing data in epidemiological and clinical research: potential and pitfalls.  BMJ. 2009;338:b2393. doi:10.1136/bmj.b2393PubMedGoogle ScholarCrossref
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