H1N1 in pregnancy poses serious threat to fetus

August 1, 2010

Pregnant women admitted ot the hospital with pandemic novel influenza A (H1N1) are at increased risk for fetal distress, premature delivery, emergency cesarean delivery, and fetal death, according to an observational analysis.

Pregnant women admitted to the hospital with pandemic novel influenza A (H1N1) are at increased risk for fetal distress, premature delivery, emergency cesarean delivery, and fetal death, according to an observational analysis of 18 women (mean age, 27 years) admitted to 2 urban academic medical centers in New York. Median hospital stay was 4 days. All were treated with oseltamivir phosphate from the first day of their admission to the hospital.

Fourteen patients (78%) tested positive for H1N1 on initial or repeated direct antigen testing of nasopharyngeal swabs; the other 4 (22%) were diagnosed with H1N1 by viral culture of rPT-PCR. Gastrointestinal or abdominal symptoms, including pain, nausea, vomiting, and diarrhea, were the presenting symptoms in about half of the women, and almost three-quarters (72%) had sepsis. The most common comorbidities were asthma, sickle cell disease, and diabetes. Three women (17%) required intensive care unit admission. Seven women (39%) delivered during hospitalization, all but 1 of them prematurely (<37 weeks' gestation) and 4 via emergency cesarean delivery. There were 2 fetal deaths (11%).

Unlike trends with previous flu epidemics, none of the mothers died, perhaps because of early use of oseltamivir phosphate, which was started in all cases on the day of admission. No congenital birth defects were reported.