Online recruitment of a non-help-seeking sample for an internet intervention: Lessons learned in an alcohol-exposed pregnancy risk reduction study.

•We sought to identify affordable and efficient methods to recruit a non-help-seeking sample of women at risk for alcohol-exposed pregnancy.•We placed free advertisements and study notices using Facebook, Twitter, Craigslist, traditional flyers and university website postings, and ClinicalTrials.gov.•Free online advertising for study participants on Craigslist was the most successful recruitment method, resulting in enrollment of 51 (68%) of the 75 study participants.•By using national data to target specific risk factors, and by tailoring advertising efforts, it is possible to efficiently and affordably recruit a non-help seeking sample.