BACKGROUND Pregnancy and the postpartum period provide windows of opportunity to impact perinatal and lifelong preventive health behavior for women and their families, but these opportunities are often missed. Understanding racial/ethnic differences in information and communication technology (ICT) use could inform technology-based interventions in diverse populations. OBJECTIVE The objective of the study was to evaluate differences in the use of ICT between racial and ethnic groups as well as by English language proficiency. METHODS We conducted a cross-sectional study of 246 women who were aged 18 years or older and pregnant or within 1 year of delivery. They were recruited from 4 hospital-based outpatient clinics and completed a self-administered survey. We used multivariate regression analysis to evaluate the association between race/ethnicity and ICT (mobile phone/short message service [SMS] text message, Internet, and social network) usage by race/ethnicity and perceived English language proficiency after adjusting for age, income, marital status, and insurance status. RESULTS In all, 28% (69/246) of participants were Latina, 40% (98/246) were African American, 23% (56/246) were white, and 9% (23/246) from other racial/ethnic groups. Of the Latinas, 84% (58/69) reported limited English language proficiency and 59% (41/69) were uninsured. More than 90% of all participants reported mobile phone use, but more than 25% (65/246) had changed phone numbers 2 or more times in the past year. Compared to white women, African American women were less likely to SMS text message (OR 0.07, 95% CI 0.01-0.63) and Latinas were less likely to use the Internet to find others with similar concerns (OR 0.23, 95% CI 0.08-0.73). Women with limited English language proficiency were less likely to use the Internet overall (OR 0.30, 95% CI 0.09-0.99) or use email (OR 0.22, 95% CI 0.08-0.63) compared to women with adequate English language proficiency. CONCLUSIONS Mobile phones are widely available for the delivery of health interventions to low-income, racially diverse pregnant and postpartum women, but disparities in Internet use and SMS text messaging exist. Interventions or programs requiring Web-based apps may have lower uptake unless alternatives are available, such as those adapted for limited English proficiency populations.