Background: Necrotizing fasciitis is an uncommon, rapidly progressive,
life-threatening infection involving the subcutaneous tissue and fasc
ia. Usually, it is a synergistic polymicrobic infection that occurs in
patients with coexisting factors predisposing them to bacterial inocu
lation and the spread of infection. Cases: We report a monomicrobial v
ariant of necrotizing fasciitis affecting three otherwise healthy preg
nant or postpartum women. The necrotizing fasciitis involved either th
e lower extremity or the abdominal wall. The causative bacteria were S
teptococcus pyogenes (two cases) and Staphylococcus aureus (one). All
patients presented with an acute fulminant infection, including one wo
man who died from overwhelming sepsis. Conclusion: These cases raise a
question about the possible role of increased bacterial virulence and
the immunologic changes of pregnancy as potential predisposing factor
s in the development of necrotizing fasciitis.