<p>Pregnancy category B. There are no adequate and well-controlled studies in pregnant women. This drug should be used during pregnancy only if clearly needed. Small amounts of cefprozil (&lt;0.3% of dose) have been detected in human milk following administration of a single 1 gram dose to lactating women. Caution should be exercised when cefprozil is administered to a nursing woman, since the effect of cefprozil on nursing infants is unknown.</p>