Alport syndrome is a familial progressive nephritis. The most frequent type is X-linked Alport syndrome, caused by genetic abnormalities in the alpha 5 chain of type IV collagen. Skin biopsy is a useful tool for diagnosing this disease. It is not well known how this syndrome affects pregnancy and how it is affected by pregnancy, or whether the umbilical cord may provide material for detecting this collagen abnormality. We report a primigravida with Alport syndrome with mild proteinuria who gave birth abdominally to a term male infant without deteriorating renal function during pregnancy. The umbilical cord from not only this infant but also from an Alport (-) control infant showed negative immunofluorescence staining for the alpha 5 chain of type IV collagen. Women with Alport syndrome without renal dysfunction may follow an uneventful obstetrical course until term. The cord may not be suitable for diagnosing Alport syndrome with immunofluorescence staining.