[1] Baylor Coll Med, Div Maternal Fetal Med, Dept Obstet, Houston, TX USA
[2] Baylor Coll Med, Dept Obstet & Gynecol, Houston, TX USA
[3] Univ N Carolina, Sch Med, Chapel Hill, NC USA
[4] Univ Utah Hlth, Salt Lake City, UT USA
[5] Univ Colorado, Sch Med, Aurora, CO USA
[6] Northwestern Univ, Feinberg Sch Med, Chicago, IL USA
[7] Univ North Carolina Chapel Hill, Evidence Based Practice Ctr, RTI Int, Res Triangle Pk, NC USA
[8] Univ N Carolina, Cecil G Sheps Ctr Hlth Serv Res, Chapel Hill, NC USA
[9] Univ North Carolina Chapel Hill, Dept Maternal & Child Hlth, Gillings Sch Global Publ Hlth, Chapel Hill, NC USA
[10] Univ North Carolina Chapel Hill, Dept Epidemiol, Gillings Sch Global Publ Hlth, Chapel Hill, NC USA
[11] Univ Massachusetts, Dept Obstet & Gynecol, Chan Med Sch, Worcester, MA USA
[12] Univ Massachusetts, Dept Pediat, Chan Med Sch, Worcester, MA USA
[13] Univ Massachusetts, Dept Psychiat, Chan Med Sch, Worcester, MA USA
[14] Univ Massachusetts, Dept Populat & Quantitat Hlth Sci, Chan Med Sch, Worcester, MA USA
[15] Univ N Carolina, Dept Psychiat, Sch Med, Chapel Hill, NC USA