Pneumonia in the Pregnant Patient

Community acquired pneumonia is a common illness, and pneumonia and influenza serve as the seventh leading cause of death in the United States. In the pregnant patient, pneumonia is the most common cause of fatal non-obstetric infection (1–3). Pneumonia can have adverse consequences for both the mother and her fetus, with certain infections (particularly viral and fungal) assuming greater virulence and mortality than in non-pregnant women of similar age (2, 3). Pneumonia is a relatively common cause of respiratory failure in pregnant patients, but in contrast to older studies, newer data suggest that not all pneumonias are more common or more serious in pregnant women than in other populations. However, because pneumonia can impact both the mother and fetus, it may lead to an increased likelihood of complicated preterm delivery, compared to pregnancies in which infection is absent. The pathogens responsible for community-acquired pneumonia (CAP) are similar in pregnant and non-pregnant patients, with Streptococcus pneumoniae, Hemophilus influenzae, Mycoplasma pneumoniae, Legionella spp., Chlamydophila pneumoniae, and influenza A accounting for the majority of cases (2–4). However, reduction in cell-mediated immunity associated with pregnancy (especially during the third trimester) places women at an increased risk of more severe forms of pneumonia and disseminated diseases from pathogens normally contained by this type of immune response, including herpes virus, influenza, varicella, and coccidioidomycosis (3, 5–7).