The practical message is that cannabis risk is not static across development or across sex. A child who is not reported at birth after prenatal exposure can still enter CPS later, so the absence of an immediate report should not be mistaken for absence of risk. In adolescents, susceptibility is already measurable by ages 9 to 10 and rises sharply by early adolescence, which makes parental monitoring, school connectedness, and neighborhood safety clinically relevant prevention targets. The Ontario data also remind us that female youth are no longer a low-prevalence group for all cannabis outcomes, so screening should not rely on old assumptions about who is most likely to use or be harmed.

In California births in 2018, fewer than 14% of prenatally substance-exposed children had a CPS report for maltreatment harm or a substantiated CPS report by age 5, but exposed children still had a higher adjusted risk difference of 0.03 for maltreatment harm and 0.03 for substantiated reports versus unexposed infants. That excess risk was also seen in the subgroup with cannabis-only exposure, with an adjusted risk difference of 0.03 (95% CI 0.02 to 0.04). In the ABCD cohort, cannabis-use susceptibility among never-users rose from 5.8% at ages 9 to 10 to 22.7% at ages 13 to 14 across 11,868 youth and 33,181 person-wave observations, with higher susceptibility linked to economic hardship, prior non-cannabis substance use, parental substance use, and impulsivity traits. In Ontario, the male-to-female ratio for past-month cannabis use fell significantly from 1999 to 2023, with the ratio crossing below 1 by 2023, meaning higher prevalence among female youth for past-month, daily, and past-year use, while dependence symptoms, initiation before Grade 9, and driving after use remained more common in males.

These findings matter because they point to two different clinical pressure points, prenatal exposure and early adolescent initiation risk, where small shifts in risk can translate into meaningful downstream harm. They also suggest that cannabis counseling cannot be one-size-fits-all, since sex patterns, family context, and social environment are changing and should shape prevention and monitoring. For harm reduction, the prenatal study argues for support services when substance exposure is identified, even if the newborn is not reported at birth, while the adolescent studies support earlier screening for susceptibility and household risk factors before use starts.

This cannabis news and regulatory roundup preserves key signals across 3 updates without overstatement, offering grounded guidance for patients and practitioners.

This curated cannabis news and regulatory roundup brings together 3 key developments across policy, market milestones, and health regulations. Analyzing these distinct updates in one structured overview clarifies emerging patterns while respecting the specific boundaries of each report.

Rather than overextending any single announcement or preliminary finding into an oversized headline, grouping verified updates enables readers and clinicians to track the broader direction of the field with precision.

Title & Source: Prenatal substance exposure and 5-year child protection outcomes among infants not reported at birth. (PubMed, 2026)

Lead Authors & Identifiers: Julia Reddy, Davida M Schiff, Anna Austin, Hendree E Jones, Laura J Faherty, Rebecca Rebbe, Anissa Vines, Emily Putnam-Hornstein. | Primary Record: DOI: 10.1371/journal.pone.0357388 | PMID: 42776927 Content lane: Safety Signal.

1. Scientific & Clinical Background: This retrospective cohort study examined California births in 2018 to see whether prenatal substance exposure predicted child protection system involvement by age 5 among infants not reported at birth. The clinical question was whether children who left the hospital without a maltreatment report still carried elevated later risk.

2. Detailed Findings & Primary Data: By age 5, fewer than 14% of exposed children had CPS reports of maltreatment harm or substantiated CPS reports. Compared with unexposed infants, exposed children had an adjusted risk difference of 0.03 for maltreatment harm and 0.03 for substantiated CPS reports, and the cannabis-only subgroup also had an adjusted risk difference of 0.03 (95% CI 0.02 to 0.04) for maltreatment harm.

3. Dr. Caplan’s Clinical & Practical Guidance: Prenatal cannabis exposure should trigger follow-up planning, not reassurance based only on a clean newborn discharge. Families may benefit from early support services, especially when exposure occurs in a broader substance-use context.

4. Study Boundaries & Methodological Limits: This is observational and vulnerable to confounding by social adversity, co-use, and differential reporting. It also measures CPS involvement, not direct child maltreatment, so the endpoint reflects system contact as well as harm.

Title & Source: Changes in Susceptibility to Cannabis Use From Late Childhood to Early Adolescence. (PubMed, 2026Sep22)

Lead Authors & Identifiers: Zihan Tang, Hongying Daisy Dai. | Primary Record: DOI: 10.1016/j.jadohealth.2026.07.008 | PMID: 42776099 Content lane: Safety Signal.

1. Scientific & Clinical Background: This ABCD analysis followed 11,868 youth across five waves, totaling 33,181 person-wave observations, to study cannabis-use susceptibility among never-users from ages 9 to 10 through 13 to 14. The outcome was a psychosocial openness construct, not actual cannabis initiation.

2. Detailed Findings & Primary Data: Susceptibility increased from 5.8% at baseline to 22.7% at 4-year follow-up among never-users. Higher susceptibility was associated with economic hardship, prior non-cannabis substance use, parental substance use, and impulsivity-related traits, while parental monitoring, favorable school environment, and perceived neighborhood safety were associated with lower susceptibility.

3. Dr. Caplan’s Clinical & Practical Guidance: This supports screening for family substance use, household monitoring, and school or neighborhood stressors before cannabis use begins. Prevention efforts can be aimed at the environment around the child, not just the child’s stated intentions.

4. Study Boundaries & Methodological Limits: Susceptibility is a proxy for future use, not use itself. The associations may vary by developmental stage, and residual confounding remains possible despite multivariable and pooled modeling.

Title & Source: Trends in the sex ratio of cannabis use, harms and perceptions among youth in Ontario, Canada, 1999 to 2023. (PubMed, 2026Sep23)

Lead Authors & Identifiers: Justin Matheson, Angela Boak, Huan Jiang, Yeshambel T Nigatu, Tara Elton-Marshall, Sergio Rueda, Farihah Ali, Dafna Sara Rubin-Kahana, Liisa A M Galea, Hayley A Hamilton, Jürgen Rehm, Bernard Le Foll, Sameer Imtiaz. | Primary Record: DOI: 10.1111/add.70607 | PMID: 42775603 Content lane: Evidence Check.

1. Scientific & Clinical Background: This Ontario school-based survey analysis used 106,815 students from 1999 to 2023 to examine whether the sex gap in cannabis use, harms, and perceptions changed over time. The study calculated male-to-female ratios for use, harm, and perception outcomes and tested trends with joinpoint regression.

2. Detailed Findings & Primary Data: Male-to-female ratios for past-month cannabis use, daily past-month use, and past-12-month use declined significantly over time, with 2023 showing higher prevalence among female youth for those use outcomes. Perceived ease of obtaining cannabis also shifted similarly, while perceived great risk of harm, initiation before Grade 9, dependence symptoms, and driving after use remained higher among males and did not show significant ratio change.

3. Dr. Caplan’s Clinical & Practical Guidance: Screening should not assume boys are the only or primary cannabis-use group anymore. Prevention and counseling need to include girls and young women, especially for use frequency, access, and evolving social norms.

4. Study Boundaries & Methodological Limits: This is repeated cross-sectional surveillance, so it cannot track individual trajectories or explain why the sex gap changed. It also uses sex at birth only and may not capture youth outside the school system.

These papers do not prove that prenatal cannabis exposure alone causes later CPS involvement, or that cannabis exposure itself is the direct driver of the observed child protection outcomes. They also do not show that susceptibility in preteens necessarily becomes use, or that the changing sex ratio in Ontario reflects biology rather than shifting social norms, access, or reporting patterns.

These findings fit with a broader shift in cannabis epidemiology, where prevention is moving earlier, from adolescent use toward pre-use susceptibility and family context. They also align with growing attention to prenatal substance exposure as a marker for later social and child welfare risk, not just a neonatal issue.

The sex-ratio trend in Ontario adds to the larger literature showing that cannabis patterns are changing faster than many screening habits in pediatrics and adolescent medicine. At the same time, the ABCD data reinforce that household monitoring and school climate remain modifiable targets, which is where prevention efforts still have the best chance to work.

What stands out is how much of cannabis risk is really about timing and context. Prenatal exposure is not just a delivery-room issue, because later child welfare involvement still occurs even when the newborn leaves the hospital without a report. That argues for practical support, not just documentation, especially when cannabis is part of a broader substance-use picture.

The adolescent data are a reminder that curiosity starts before use. By middle school, susceptibility is already common enough to matter, and it tracks with family substance use, hardship, and weaker monitoring. In real life, that means asking about home environment, school attachment, and access, not just whether a teen has already tried cannabis.

The careful takeaway is that cannabis-related risk shows up early, shifts over time, and is shaped by family and social context. Prevention should focus on prenatal support, early adolescent screening, and updated assumptions about which youth are most at risk.

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