Is postpartum pyelonephritis associated with the same maternal morbidity as antepartum pyelonephritis?

Pregnant women with pyelonephritis are at higher risk for significant morbidty than nonpregnant women with pyelonephritis. The risk from pregnancy may continue into the postpartum period. Many of the physiologic and hormonal changes that occur during pregnancy persist after delivery. The objective of this study was to compare maternal morbidity in postpartum and antepartum pyelonephritis.

A retrospective cohort analysis included all pregnant and postpartum women hospitalized for pyelonephritis at a single tertiary care hospital between January 2004 and June 2007. The postpartum period was defined as up to 6 weeks from delivery. The primary outcome measure was maternal morbidity measured by length of hospitalization.

256 cases of antepartum pyelonephritis and 23 cases of postpartum pyelonephritis were included in the analysis. Women in both groups were admitted for a mean of 4 days (p = 0.3). Women who were diagnosed in the postpartum period were more likely to be febrile (91.3% vs. 51.7%, p = 0.0001) and had a higher temperature on presentation (102.9°F vs. 99.1°F p < 0.0001).

Pyelonephritis was equally morbid in the postpartum and antepartum periods. Postpartum pyelonephritis may warrant the same close inpatient observation as antepartum pyelonephritis.