ObjectiveTo assess how mothers' choice of e-mail or text messages (SMS) to receive safe sleep communications is associated with educational video viewing and responses to care practice queries. MethodsSeven hundred ninety-two new mothers received safe sleep-related communications for 60 days after newborn hospital discharge as part of a trial of health education interventions on infant care practices. Mothers chose e-mail or SMS for study communications and were sent 22 short safe sleep videos and 41 queries regarding infant care practices. ResultsStudy communications via e-mail were elected by 55.7% of participants. The SMS group had a modestly higher overall view rate of videos (59.1% vs 54.4%; adjusted odds ratio [aOR], 1.39; 95% confidence interval [CI], 1.07–1.81) and a substantially higher response rate to queries (70.0% vs 45.2%; aOR, 3.48; 95% CI, 2.74–4.43). ConclusionsParticipants more commonly opted to receive infant care practice videos and queries via e-mail. SMS was associated with higher viewing and response rates, especially for query responses. These results highlight the importance of understanding how specific modalities of communication might vary in reach.