Adjusted and unadjusted risk of childhood asthma exposed to maternal antibiotic use during 4 weeks before LMP and pregnancy and followed to 7 years of age.

a: adjusted for maternal age at delivery, marital status at pregnancy, race, educational level, parity, smoking during pregnancy, maternal asthma history, and maternal history of drug allergy.b: The precise value can’t becalculated, because the sample size was too small to analyze.LMP: last menstrual periodAdjusted and unadjusted risk of childhood asthma exposed to maternal antibiotic use during 4 weeks before LMP and pregnancy and followed to 7 years of age.