title: Response to Brent.
authors.forename: Philippe P
authors.initials: PP
authors.lastname: Hujoel
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Bollen
authors.forename: Carolyn J
authors.initials: CJ
authors.lastname: Noonan
mesh_terms: D000818:Animals; D015986:Confounding Factors, Epidemiologic; D005260:Female; D005317:Fetal Growth Retardation / Q000209:etiology*; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D018811:Maternal Exposure / Q000009:adverse effects*; D011247:Pregnancy; D011829:Radiation Dosage; D011859:Radiography / Q000009:adverse effects*; D012307:Risk Factors