Fig. 1.

Overview of the HBCD Study protocol starting from the prenatal visit (Visit 1) to 17 months of age (Visit 5). The study protocol contains assessments across a wide range of domains (Nelson et al., this issue) including pregnancy exposures (e.g., substance use, mental health; Gurka et al., this issue), social and environmental determinants of health (Cioffredi, Yerby, et al., this issue), physical health (Cioffredi, Garner, et al., this issue), child behavior and child-caregiver relationships (Edwards et al., this issue), and neurocognition and language development (Kable et al., this issue). Biospecimens are collected from both the birth parent and child to identify biomarkers and classify exposures (Sullivan et al., this issue) and wearable biosensors calculate infant movement and heartbeat (Pini et al., this issue). Measures of brain structure and function begin with collection of MRIs starting in the first month of life (Dean et al., this issue) and EEGs starting at 3 months of age (Fox et al., this issue). Protocol development is ongoing for additional visits through 10 years of age.