Maternal smoking during pregnancy, prematurity and recurrent wheezing in early childhood

Background Prenatal maternal smoking and prematurity independently affect wheezing and asthma in childhood. Objective We sought to evaluate the interactive effects of maternal smoking and prematurity upon the development of early childhood wheezing. Methods We evaluated 1,448 children with smoke exposure data from a prospective urban birth cohort in Boston. Maternal antenatal and postnatal exposure was determined from standardized questionnaires. Gestational age was assessed by the first day of the last menstrual period and early prenatal ultrasound (preterm?