Maternal smoking linked to poor infant immunity

A new study has revealed that smoking during pregnancy is associated with both respiratory and non-respiratory infections in infants, resulting in increased risk for hospitalization and death.

"We've known for a long time that babies born to mothers who smoke during pregnancy are at high risk for serious medical problems relating to low birth weight, premature delivery and poor lung development," lead study author Abigail Halperin, MD, MPH said.

Halperin said that while respiratory infections have been recognized as a common cause of these sometimes life-threatening illnesses, this study shows that babies exposed to smoke in utero also have increased risk for hospitalization and death from a much broader range of infections- both respiratory and non-respiratory- than we knew before.

The researcher said that the findings were largely independent of birth weight and gestational age, thus even full-term babies with normal weight are at increased risk for hospitalization or death from multiple types of infections if their mother smoked.

The results suggest that exposure to smoke during pregnancy harms infants' immune responses more generally, not just within the respiratory system, she said.

The study also found that when mothers cut back on their cigarette smoking or quit part way through their pregnancy, it seems to lower their child's risk of infection, Halperin said.

The study is to be presented at the American Academy of Pediatrics (AAP) National Conference and Exhibition in Orlando.