Pneumonia reportedly increases the risk of maternal and fetal illness and death, and in the United States is a significant cause of nonobstetrical maternal death. Maternal mortality has fallen dramatically since the advent of antibiotics. This prospective study enrolled 28 women who developed pneumonia while pregnant, and presented with signs and symptoms thereof, as well as an acute pulmonary infiltrate, to one of six hospitals in Edmonton, Alberta during a 2-year period in 2001–2003. The incidence was 1.1 per 1000 deliveries. A comparison group included 333 nonpregnant women 20 to 40 years of age who had pneumonia (incidence, 1.3 per 1000).
The commonest symptoms of pneumonia in pregnant women were cough, fever, and shortness of breath. None of those affected had received influenza vaccine. Cough, fever, and sputum production dominated in nonpregnant women. Co-morbid conditions were conspicuously absent in the pregnant women. In contrast, the nonpregnant group included women with chronic obstructive lung disease, diabetes, heart disease, liver disease, cancer, and HIV infection. The gestational age when pneumonia developed averaged 29 weeks; more than half the patients were in the third trimester. In no pregnant woman was multilobar involvement observed, but four pregnant women had pleural effusion. Levels of hemoglobin, hematocrit, and albumin all were lower in pregnant women. All of the pregnant women had relatively low scores for severity of illness using the PORT (Pneumonia Patient Outcome Research Team) system. More than 95% of the comparison group also had low-risk PORT scores.
Apart from an abortion at 10 weeks’ gestation there were no fetal deaths. Live-born infants had a mean birth weight of 3320 gm and a mean 1-minute Apgar score of 8.6. None of the newborn infants had evident anomalies. The only woman who died was not pregnant. The 28 pregnant women received many different antibiotics, most commonly cefuroxime, azithromycin, and erythromycin. Pregnant women were twice as likely to be admitted to hospital than nonpregnant women in the same age group, but they had a shorter length of stay.
These findings suggest that pregnant women tolerate pneumonia well and are unlikely to develop pulmonary or immunological complications. Pregnancy itself does not increase the risk of pneumonia. Neither the clinical findings nor the outcomes differ from those in nonpregnant women with pneumonia.