Systemic tocolysis for premature labor is associated with an increased incidence of pulmonary edema in the presence of maternal infection

Our hypothesis is that systemic tocolysis of patients in premature labor is associated with a higher incidence of pulmonary edema in the presence of maternal infection. Over a 64-month period, medical records of all patients with a diagnosis at discharge of pulmonary edema or congestive heart failure were reviewed. There were 27 cases of pulmonary edema, 16 of which (59.3%) were associated with treatment of preterm labor. The incidence of pulmonary edema in patients receiving systemic tocolysis for treatment of preterm labor was significantly higher than that in our general obstetric population (3.04% versus 0.05%). Of the 527 patients receiving tocolysis, there was evidence of maternal infection in 52. The incidence of pulmonary edema was higher in the presence of maternal infection than in its absence (11/52 or 21% versus 5/475 or 1%, p = 0.0000). We conclude that there is a very strong association between the development of pulmonary edema and the presence of maternal infection in patients being treated for premature labor with systemic tocolysis.