Reproduction studies have been performed in animals at doses up to moderately maternally toxic dose concentrations. In these animal studies, no evidence of harm to the fetus due to azithromycin was found. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, azithromycin should be used during pregnancy only if clearly needed.
It is not known whether azithromycin is excreted in human milk. Because many drugs are excreted in human milk, azithromycin should not be used during breast-feeding unless the doctor decides the potential benefit justifies the potential risk to the foetus.