We assessed attitudes of a multi-ethnic sample of pregnant women in regard to participation in five data collection procedures planned for use in the National Children's Study. A cross-sectional survey was conducted in nine prenatal clinics in Kent County, Michigan between April and October 2006. Women were approached in clinic waiting rooms at the time of their first prenatal visit and 311 (91.0%) participated. Women were asked about their willingness to participate, and the smallest amount of compensation required for participation in a 45-min in-person interview, a 15-min telephone interview, maternal and infant medical record abstraction, and an infant physical examination. Percentages for willingness to participate were highest for telephone interview (83%), followed by in-person interview (60%), infant examination (57%), and maternal (56%) and infant medical records (54%). About 34-48% of women reported that no compensation would be required for participation by data procedure. Some women reported unwillingness to participate in telephone (9%) or personal (17%) interview, record abstraction (34%) or infant examination (26%), even with compensation. Education greater than high school was associated with increased odds of refusal for infant physical examination, adjusted odds ratio 2.44 [95% confidence interval 1.41, 4.23]. In conclusion, 9-34% of pregnant women, depending on procedure, stated they would not participate in non-invasive research procedures such as medical record abstraction and infant examination, even with compensation. Resistance to these research procedures was especially noted among more highly educated women. Planning for the National Children's Study will have to address potential resistance to research among pregnant women.