443 - Postnatal Head Ultrasound Findings in Preterm Infants Exposed Prenatally to Marijuana

Publication Number: 443.6421

Mimily Harsono, University of Tennessee Health Science Center College of Medicine, memphis, TN, United States; Divya Rana, UTHSC, Memphis, TN, United States; Harris L.. Cohen, University of Tennessee ; LeBonheur Children’s Hospital, Memphis, TN, United States; massroor pourcyrous, UTHSC Memphis TN, Mempbhis, TN, United States

Background: The growing legalization trends on Marijuana use for medical or non-medical purposes have impacted the rising use of marijuana. The major psychoactive constituent in marijuana is delta-9-tetrahydrocannabinol (THC). Legalization of marijuana use with its presumed safety perception has made marijuana the most commonly use illicit substance during pregnancy. Marijuana use in pregnancy has been associated with premature birth, low birth weight, microcephaly and neurodevelopmental issues. However, there is no report on postnatal head ultrasound (HUS) findings of in-utero THC-exposed premature infants.

Objective: We hypothesize that in-utero exposure to THC increases the risk of abnormal postnatal HUS findings in premature infants.

Design/Methods: Prospective observational cohort study of preterm infants who were exclusively exposed to THC prenatally. Per our NICU guidelines for preterm infants with gestational age (GA) < 32 weeks or birth weight (BW) < 1,500 grams, serial postnatal HUS are obtained within the first 14 days, at 21-28 days of life and at corrected GA 36 weeks. We included all live birth preterm infants that were born in 2014-2020. We excluded infants with complex congenital anomalies, chromosomal anomalies, and other non-THC illicit substances exposure. In-utero exposure to THC was identified via maternal history, maternal urine toxicology test and confirmed with post-natal umbilical cord tissue toxicology test.

Results: We included 1,135 preterm infants evaluated over the 7 years period. In-utero exposure exclusively to THC was confirmed in 26 infants (2.3%). Abnormal postnatal HUS was defined based on the worst findings identified in the first 28 days of life. The incidence of IVH in non-THC exposed infants was as follows: grade-I 19.6%, grade-II 7.8%, grade-III 2.9% and grade-IV 6.3%. Of the THC-exposed infants, 73.1% [OR: 4.69; CI: 1.96-11.25; p= 0.0005] had abnormal postnatal HUS. The incidence of IVH in THC-exposed infants was as follows: grade-I 46.2% (12/26), grade-II 19.2% (5/26), grade-III 3.8% (1/26), and no grade-IV. Table.1&2 summarized maternal and infant characteristics.

Conclusion(s): The incidence of IVH grade-I and -II was significantly higher in premature infants who were prenatally exposed to THC. Neurodevelopmental follow up is needed to evaluate the long-term outcome of the THC-exposed infants.

Table 1. Characteristics of Premature infants (GA < 32 wk; BW < 1,500 g) with In-utero THC Exposure


Table. 2 Characteristics of Mothers Who Used Tetrahydrocannabinol (THC) during Pregnancy