With the emerging infectious disease threat of pandemic avian influenza, obstetricians should be aware of the disproportionate morbidity and mortality documented among gravidas in the twentieth century pandemics. To date the majority of fatal cases of H5N1 avian influenza have been recorded in young previously healthy adults, reminiscent of the epidemiology of the 1918 “Spanish flu” pandemic. All providers of obstetric services and all facilities providing obstetric care have a key role in terms of pandemic planning for our potentially disproportionately affected, vulnerable patient population. This article summarizes the relevant data and frames the current threat to obstetric providers and facilities posed by H5N1 avian influenza in terms of pandemic potential. In addition, suggestions for basic pandemic planning efforts are reviewed.