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

Predictors for cannabis cessation during pregnancy: a 10-year cohort study

The aim of this study is to determine factors associated with cannabis discontinuation, to assess the impact of mental health and addiction interventions on cannabis discontinuation during pregnancy and to investigate the neonatal impact of cannabis discontinuation. This is a 10-year cohort study in a tertiary hospital in Barcelona, Spain, including women with self-reported cannabis use during pregnancy. Main outcome was cannabis discontinuation based on biological sample testing. Secondary outcomes were neonatal intensive care unit (NICU) admission, preterm birth, birth weight and bottle-feeding. When cannabis use was detected during pregnancy, 32 out of 81 (38.3%) discontinued cannabis during pregnancy vs. four out of 61 (6.6%) when detected at birth (p < .001). Multivariate binary logistic regression showed that null parity (OR: 6.95, p = .011), detection of cannabis use during pregnancy (OR: 5.35, p = .018) and early detection and referral to mental health care for counseling on cannabis cessation and interventions on the first trimester (OR: 25.46, p < .001) increased cannabis discontinuation. Risk for preterm birth <37 weeks (11.4% vs. 30.8%) and NICU admission (25.7% vs. 54.2%) were lower when discontinuation. Early detection of cannabis use during pregnancy, cessation counseling with mental health interventions, and null parity are predictors for cannabis discontinuation during pregnancy.

The longitudinal assessment of prenatal cannabis use on neonatal outcomes

OBJECTIVE

To investigate the association between prenatal cannabis use and perinatal outcomes using longitudinal data from pregnant individuals.

STUDY DESIGN

This secondary-data analysis study utilized data collected from 894 pregnant individuals followed in the Stress in Pregnancy longitudinal study, conducted between 2009 and 2013. The status of cannabis use was ascertained through interviews and electronic medical record reviews to evaluate the effect of cannabis use on perinatal outcomes (NICU admission, preterm delivery, low birth weight, fetal death).

RESULTS

Among participants analyzed, 13.1% used cannabis, who were generally younger (25.9 vs 27.9 years). There was a sevenfold increased risk of fetal death (OR 7.30) among cannabis users relative to non-users. Elevated risk persisted after adjustments of potential confounders (aOR 6.31). Adjusted models also suggested increased low birth weight risk (aOR 1.67).

CONCLUSION

This study highlights an association between prenatal cannabis use and elevated risks for fetal death and low birth weight.

Cannabis exposure during pregnancy and perinatal outcomes: A cohort study

INTRODUCTION

Cannabis potency and its use during pregnancy have increased in the last decade. The aim of this study was to investigate the impact of antenatal cannabis use on fetal growth, preterm birth and other perinatal outcomes.

MATERIAL AND METHODS

A propensity score-matched analysis was performed in women with singleton pregnancies attending a tertiary care site in Barcelona. Women in the cannabis group were selected based on the results of a detection test. Primary outcomes were small for gestational age at birth (SGA), low birthweight and preterm birth. Secondary outcomes were other biometric parameters (neonatal length and head circumference), respiratory distress, admission to the neonatal intensive care unit and breastfeeding at discharge. A second propensity score-matched analysis excluding other confounders (use of other recreational drugs and discontinuation of cannabis use during pregnancy) was performed.

RESULTS

Antenatal cannabis was associated with a higher odds ratio of SGA (OR 3.60, 95% CI: 1.68-7.69), low birthweight (OR 3.94, 95% CI: 2.17-7.13), preterm birth at 37 weeks (OR 2.07, 95% CI: 1.12-3.84) and 32 weeks of gestation (OR 4.13, 95% CI: 1.06-16.11), admission to the neonatal intensive care unit (OR 1.95, 95% CI: 1.03-3.71), respiratory distress (OR 2.77, 95% CI: 1.26-6.34), and lower breastfeeding rates at discharge (OR 0.10, 95% CI: 0.05-0.18). When excluding other confounders, no significant association between antenatal cannabis use and SGA was found.

CONCLUSIONS

Antenatal cannabis use increases the risk of SGA, low birthweight, preterm birth and other adverse perinatal outcomes. However, when isolating the impact of cannabis use by excluding women who use other recreational drugs and those who discontinue cannabis during pregnancy, no significant association between antenatal cannabis use and SGA birth was found.

Cannabis use, decision making, and perceptions of risk among breastfeeding individuals: the Lactation and Cannabis (LAC) Study

OBJECTIVE

Our primary objective was to understand breastfeeding individuals' decisions to use cannabis. Specifically, we investigated reasons for cannabis use, experiences with healthcare providers regarding use, and potential concerns about cannabis use.

METHODS

We collected survey data from twenty breastfeeding participants from Washington and Oregon who used cannabis at least once weekly. We documented individuals' cannabis use and analyzed factors associated with their decisions to use cannabis during lactation. Qualitative description was used to assess responses to an open-ended question about potential concerns.

RESULTS

Fifty-five percent of participants (n = 11) reported using cannabis to treat or manage health conditions, mostly related to mental health. Eighty percent of participants (n = 16) reported very few or no concerns about using cannabis while breastfeeding, although participants who used cannabis for medical purposes had significantly more concerns. Most participants (n = 18, 90%) reported receiving either no or unhelpful advice from healthcare providers. Four themes arose through qualitative analysis, indicating that breastfeeding individuals are: 1) identifying research gaps and collecting evidence; 2) monitoring their child's health and development; 3) monitoring and titrating their cannabis use; and 4) comparing risks between cannabis and other controlled substances.

CONCLUSIONS

Breastfeeding individuals reported cannabis for medical and non-medical reasons and few had concerns about cannabis use during breastfeeding. Breastfeeding individuals reported using a variety of strategies and resources in their assessment of risk or lack thereof when deciding to use cannabis. Most participants reported receiving no helpful guidance from healthcare providers.

Use of E-Cigarettes and Cigarettes During Late Pregnancy Among Adolescents

Importance

Pregnant adolescents sometimes use cigarettes; however, little is known about e-cigarette use among pregnant adolescents, a population with increased health vulnerability.

Objective

To examine yearly trends, sociodemographic and pregnancy-related determinants, and the association with small-for-gestational-age (SGA) birth of e-cigarette and/or cigarette use during late pregnancy among adolescents.

Design, Setting, and Participants

This cohort study used existing data from the 2016-2021 Pregnancy Risk Assessment Monitoring System on 10 428 US adolescents aged 10 to 19 years who had a singleton birth with complete data on e-cigarette or cigarette use and SGA birth.

Exposure

Adolescents reported e-cigarette and cigarette use during the last 3 months of pregnancy.

Main Outcomes and Measures

SGA birth (birth weight below the 10th percentile for the same sex and gestational duration) was determined from birth certificates. Multivariable logistic regression was used to compare the odds of SGA birth across pregnant adolescents who exclusively used e-cigarettes, exclusively used cigarettes, used e-cigarettes and cigarettes, or did not use either.

Results

Of the 10 428 pregnant adolescents, 72.7% were aged 18 or 19 years; 58.9% self-identified as White and 23.3% as Black; and 69.8% were non-Hispanic. The weighted prevalence of exclusive e-cigarette use during late pregnancy increased from 0.8% in 2016 to 4.1% in 2021, while the prevalence of exclusive cigarette use decreased from 9.2% in 2017 to 3.2% in 2021. The prevalence of dual use fluctuated, ranging from 0.6% to 1.6%. White pregnant adolescents were more likely than those who self-identified as another race and ethnicity to use e-cigarettes (2.7% vs 1.0% for American Indian or Alaska Native adolescents, 0.8% for Asian or other race adolescents, 0.6% for Black adolescents, and 0.7% for multiracial adolescents). Compared with those who did not use either product, adolescents who exclusively used e-cigarettes (16.8% vs 12.9%; confounder-adjusted odds ratio [AOR], 1.68 [95% CI, 0.89-3.18]) or who used cigarettes and e-cigarettes (17.6% vs 12.9%; AOR, 1.68 [95% CI, 0.79-3.53]) had no statistically significant difference in risk of SGA birth. However, adolescents who exclusively used cigarettes had a more than 2-fold higher risk of SGA birth (24.6% vs 12.9%; AOR, 2.51 [95% CI, 1.79-3.52]).

Conclusions and Relevance

This cohort study suggests that pregnant adolescents increasingly used e-cigarettes, with the highest use among White adolescents. Results from this analysis found that, unlike cigarette use, e-cigarette use during late pregnancy was not statistically significantly associated with an increased risk of SGA birth among adolescents. Due to the uncertainty of this nonsignificant association, future research could benefit from a larger sample size.

Patient Perceptions of Prenatal Cannabis Use and Implications for Clinicians

OBJECTIVE

To understand pregnant patients' reasons for prenatal cannabis use and perceptions of safety, desired and undesirable health care experiences, and desired information about prenatal cannabis use and secondarily to understand racial differences in these perceptions and preferences.

METHODS

We conducted a qualitative study including 18 semi-structured, race-concordant virtual focus groups with pregnant individuals who self-reported cannabis use at prenatal care entry in a large integrated health care system in Northern California from November 2021 to December 2021. The focus groups included semi-structured questions that were recorded, transcribed, and coded by the research team. Thematic analysis was used to analyze the data.

RESULTS

Overall, 53 participants were included; 30 self-identified, as White and 23 self-identified as Black. Participants averaged 30.3 years of age (SD 5.2 years) and were on average at 20.9 weeks of gestation at study enrollment; 69.8% reported daily cannabis use, 24.5% reported weekly cannabis use, and 5.7% reported monthly or less cannabis use at entrance to prenatal care. Although some participants quit cannabis use in early pregnancy because of concerns about potential health risks, many perceived a lack of scientific evidence or believed that prenatal cannabis use was safe. Many preferred cannabis to over-the-counter or prescription medications for treating mood, morning sickness, pain, and sleep. Participants valued open interactions with obstetricians that acknowledged their motivations for use, and they desired information about potential risks through conversations and educational materials. White and Black participants' perspectives were generally similar, but a few Black participants uniquely described concerns about racial bias related to their prenatal cannabis use.

CONCLUSION

Pregnant patients used cannabis to manage mood and medical symptoms, and many believed that prenatal cannabis use was safer than the use of prescription medications. Obstetrician-initiated, patient-centered conversations around prenatal cannabis use, advice to discontinue cannabis use during pregnancy, and exploration of willingness to switch to medically recommended interventions for pregnancy-related symptoms may benefit patients.

Insights into Prevention of Health Complications in Small for Gestational Age (SGA) Births in Relation to Maternal Characteristics: A Narrative Review

Small for gestational age (SGA) births are a significant clinical and public health issue. The objective of this review was to summarize maternal biological and socio-demographic factors and preventive strategies used to reduce the risk of SGA births. A literature search encompassing data from the last 15 years was conducted using electronic databases MEDLINE/PubMed, Google Scholar and Scopus to review risk factors and preventive strategies for SGA. Current evidence shows that primiparity, previous stillbirths, maternal age ≤24 and ≥35 years, single motherhood, low socio-economic status, smoking and cannabis use during pregnancy confer a significant risk of SGA births. Studies on alcohol consumption during pregnancy and SGA birth weight are inconclusive. Beneficial and preventive factors include the "Mediterranean diet" and dietary intake of vegetables. Periconceptional folic acid supplementation, maternal 25-hydroxyvitamin D, zinc and iron levels are partly associated with birth weight. No significant associations between COVID-19 vaccinations and birthweight are reported. A midwifery-led model based on early and extensive prenatal care reduces the risk of SGA births in women with low socio-economic status. Major preventive measures relate to the awareness of modifiable and non-modifiable risk factors of SGA, leading to changes in parents' lifestyles. These data support that education, monitoring during pregnancy, and implementing preventive strategies are as important as biological determinants in risk reduction of SGA births.

Effects of Prenatal Cannabinoids Exposure upon Placenta and Development of Respiratory Neural Circuits

Cannabis use has risen dangerously during pregnancy in the face of incipient therapeutic use and a growing perception of safety. The main psychoactive compound of the Cannabis sativa plant is the phytocannabinoid delta-9-tetrahydrocannabinol (A-9 THC), and its status as a teratogen is controversial. THC and its endogenous analogues, anandamide (AEA) and 2-AG, exert their actions through specific receptors (eCBr) that activate intracellular signaling pathways. CB1r and CB2r, also called classic cannabinoid receptors, together with their endogenous ligands and the enzymes that synthesize and degrade them, constitute the endocannabinoid system. This system is distributed ubiquitously in various central and peripheral tissues. Although the endocannabinoid system's most studied role is controlling the release of neurotransmitters in the central nervous system, the study of long-term exposure to cannabinoids on fetal development is not well known and is vital for understanding environmental or pathological embryo-fetal or postnatal conditions. Prenatal exposure to cannabinoids in animal models has induced changes in placental and embryo-fetal organs. Particularly, cannabinoids could influence both neural and nonneural tissues and induce embryo-fetal pathological conditions in critical processes such as neural respiratory control. This review aims at the acute and chronic effects of prenatal exposure to cannabinoids on placental function and the embryo-fetal neurodevelopment of the respiratory pattern. The information provided here will serve as a theoretical framework to critically evaluate the teratogen effects of the consumption of cannabis during pregnancy.