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.

Intrauterine cannabis exposure and fetal and maternal blood flow: a case-control study.

INTRODUCTION: Cannabis consumption during pregnancy increases the risk of pregnancy and neonatal complications. Since the underlying mechanism is unknown, the purpose of this study is to evaluate the changes in maternal and fetal blood flow in pregnancies exposed to cannabis, Δ9-tetrahydrocannabinol (THC). MATERIAL AND METHODS: A case-control study between 2013 and 2020, included women with continued cannabis exposure during the pregnancies, defined by qualitative detection of THC in urine (Cannabis Group), and low-risk pregnancy women divided into tobacco smokers (Tobacco Group), and non-tobacco smokers (Control Group). We evaluated the association between cannabis consumption and maternal and fetal blood flow parameters measured by Doppler ultrasound: uterine artery at 11-14, 20-22 and 33-35 weeks, umbilical artery and middle cerebral artery at 33-35 weeks. Cerebral-placental ratio was calculated. RESULTS: Overall, 275 participants were included, 60 in the Cannabis Group, 17 in the Tobacco Group and 198 in the Control Group. At 33-35 weeks, differences were found in the umbilical artery pulsatility index (PI) (1.05 ± 0.23, 1.06 ± 0.19, 0.93 ± 0.15, P < 0.01), middle cerebral artery PI (1.75 ± 0.35, 1.90 ± 0.45, 1.88 ± 0.34, P < 0.05), cerebral-placental ratio (1.69 ± 0.40, 1.85 ± 0.53, 2.07 ± 0.47, P < 0.05) and mean uterine artery PI (0.89 ± 0.26, 0.73 ± 0.19, 0.74 ± 0.20, P < 0.01), respectively. On logistic regression analysis, adjusted for maternal age, maternal body mass index, maternal weight and white ethnicity, both cannabis and tobacco were predictors for increased umbilical artery PI, but only cannabis was a predictor for a decreased cerebral-placental ratio and an increased uterine artery PI at 33-35 weeks. CONCLUSIONS: Data from a large cohort of continuous cannabis exposure pregnancies show that cannabis is associated with maternal and fetal blood flow changes. However, it is not possible to disentangle the association of the tobacco and cannabis.

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.

Impact of the trait anxiety during pregnancy on birth weight: an observational cohort study.

To explore the effects of antenatal anxiety on fetal growth an observational cohort study was performed, including a cohort of 204 women with singleton pregnancies during the strict lockdown of the COVID-19 pandemic in 2020. Psychosocial factors, maternal demographics, obstetric outcomes, social support (Medical Outcomes Study Social Support Survey, MOS-SSS), and symptoms of anxiety (State-Trait Anxiety Inventory, STAIs and STAIt) and depression (Edinburgh Postpartum Depression Scale, EPDS) were studied as potential predictors of low birth weight. Main outcome measures were birth weight, head circumference and length. Results showed a negative correlation between STAIt score (trait anxiety) and birth weight percentile (r = -0.228, p = .047). In the univariate linear regression analysis, a lower maternal weight and BMI before pregnancy, parity, increased STAIt score and preterm birth below 37 weeks of gestation (p = .008, p = .015, p = .028, p = .047 and p = .022, respectively) were identified as predictive risk factors for low birth weight, whereas in the multivariate lineal regression analysis only a lower maternal weight before pregnancy and an increased STAIt score were independent predictors for low birth weight (p = .020, p = .049, respectively). To conclude, anxiety during pregnancy impacts birth weight, and specifically the trait anxiety, is a predictor for low birth weight.