[1] Brown Univ, Dept Epidemiol, Providence, RI 02912 USA
[2] Icahn Sch Med Mt Sinai, Dept Pediat, Pediat Kravis Childrens Hosp, New York, NY 10029 USA
[3] Icahn Sch Med Mt Sinai, Dept Prevent Med, New York, NY 10029 USA
[4] Icahn Sch Med Mt Sinai, Mindich Child Hlth & Dev Inst, New York, NY 10029 USA
[5] Harvard Univ, Sch Publ Hlth, Dept Environm Hlth, Boston, MA 02115 USA
[6] Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA
[7] Natl Inst Publ Hlth, Ctr Evaluat Res & Surveys, Cuernavaca, Morelos, Mexico
[8] Univ Toronto, Dalla Lana Sch Publ Hlth, Toronto, ON, Canada
[9] Natl Inst Perinatol, Div Res Publ Hlth, Mexico City, DF, Mexico