We present a three-phase exploration of mobile messaging to address the high rate of maternal mortality in low-income, urban Pakistan, with a focus on identifying deviations from previously published findings about mobile interventions in developing-world health.Phase 1 was a qualitative study of healthcare staff and pregnant mothers. It found that while the deeper medical challenges of maternal mortality were beyond the reach of ICT interventions, many of the problems could be partially addressed through a mobile-phone system that issued health-related information and reminders. In Phase 2, we ran a randomized controlled trial of 180 pregnant mothers split into four arms based on the mode by which the messages were sent -- (1) no messages (control), (2) SMS text messages, (3) recorded voice messages, and (4) a combination of SMS and voice messages. Consistent with prior research, we found that mothers receiving messages exhibited dramatic gains in knowledge about pre-natal care, though whether the messages increased follow-up hospital visits was not clear.Phase 3 involved follow-up phone interviews with the participants of the Phase 2 evaluation. Complex family dynamics involving husbands and mothers-in-law mediate the impact of mobile information interventions, with both positive and negative effects.