text_1: There is no relation between Erythromycin use and hypertrophic pyloric stenosis.
text_2: The rate ratios for maternal use of macrolides during pregnancy were 1.02 (0.65 to 1.59) for weeks 0 to 27 and 1.77 (0.95 to 3.31) for weeks 28 to birth; the corresponding absolute risk differences were 0.01 (-0.31 to 0.50) and 0.67 (-0.06 to 2.02).