Design and Conduct of an Internet-Based Preconception Cohort Study in North America: Pregnancy Study Online.

Background We launched the Boston University Pregnancy Study Online ( PRESTO) to assess the feasibility of carrying out an Internet-based preconception cohort study in the US and Canada. Methods We recruited female participants age 21-45 and their male partners through Internet advertisements, word of mouth, and flyers. Female participants were randomised with 50% probability to receive a subscription to FertilityFriend.com ( FF), a web-based programme that collects real-time data on menstrual characteristics. We compared recruitment methods within PRESTO, assessed the cost-efficiency of PRESTO relative to its Danish counterpart ( Snart- Gravid), and validated retrospectively reported date of last menstrual period ( LMP) against the FF data. Results After 99 weeks of recruitment (2013-15), 2421 women enrolled; 1384 (57%) invited their male partners to participate, of whom 693 (50%) enrolled. Baseline characteristics were balanced across randomisation groups. Cohort retention was similar among those randomised vs. not randomised to FF (84% vs. 81%). At study enrolment, 56%, 22%, and 22% couples had been trying to conceive for <3, 3-5, and ≥6 months, respectively. The cost per subject enrolled was $146 (2013 US$), which was similar to our companion Danish study and half that of a traditional cohort study. Among FF users who conceived, >97% reported their LMP on the PRESTO questionnaire within 1 day of the LMP recorded via FF. Conclusions Use of the Internet as a method of recruitment and follow-up in a North American preconception cohort study was feasible and cost-effective. [ABSTRACT FROM AUTHOR]