The almost 50 million young people aged 10–24 in Nigeria face many challenges to their sexual and reproductive health (SRH). MyQuestion is a platform that allows young people to ask SRH questions via text message. Trained counselors provide responses using a database of answers to frequently asked questions or customized replies. We analyze the content of more than 300,000 text messages received by the service since 2007 to address three questions: which health topics are most frequently submitted to the MyQuestion service; what kinds of questions are asked about these topics; and what language is used to convey the questions? We find a substantial unmet need for basic SRH information, with users’ questions communicated in ways that convey considerable confusion, misinformation, and urgency. The analysis can be used to improve similar Q&A services and to improve the provision of SRH services for young people more generally.