Vaccination in pregnancy may offer protection for preemies

(HealthDay)—A combination vaccine offered to mothers from 28 weeks of gestation may offer protection for infants born prematurely, according to a study published online June 2 in Pediatrics.

Alison Kent, M.D., from St. George's at the University of London, and colleagues measured antibody concentrations at ages 2, 5, and 12 months of age in premature infants of vaccinated and unvaccinated mothers enrolled in a randomized trial of pneumococcal conjugate vaccine schedules. As part of their routine care, mothers had been offered a combination tetanus, diphtheria, five-component acellular pertussis, inactivated polio vaccine from 28 weeks of gestation.

Mothers of 19 percent of the 160 premature infants had received the vaccine in pregnancy. The researchers found that those born to vaccinated mothers had significantly higher antibody concentrations for all measured vaccine antigens at 2 months, compared with infants of unvaccinated mothers (P < 0.001). For pertussis toxin and filamentous hemoagglutinin (FHA) there was a positive correlation between the number of days between maternal vaccination and delivery and immunoglobulin G concentration at age 2 months (P = 0.011 and 0.001, respectively). Compared with infants of unvaccinated mothers, infants of vaccinated mothers had significantly lower antibody concentrations for FHA after primary immunization (P = 0.003); by 12 months of age these differences had resolved.

"Maternal vaccination administered early in the third trimester may provide protection for infants born prematurely," the authors write.

The study was partially funded by Pfizer. Two authors disclosed having conducted studies funded by vaccine manufacturers.