Newborn babies who are exposed to air pollution in the womb breathe faster to pump more oxygen into their lungs, a new study has found.

Environmental fumes can damage a child's lungs before birth, a study on 241 Swiss infants has revealed and found that the more pollution a pregnant woman breathes in, the more her baby will struggle for breath.

Australian child health experts said the findings support recent research on Brisbane mothers and help build a case for more eco-friendly town planning and better efforts to avoid pollutants in pregnancy, AAP report said here today.

"This is scary proof that we need to be paying a lot more attention to how we are designing our cities," Peter Sly, director of the WHO Collaborating Centre for Research on Children's Environmental Health in Perth said.

Respiratory specialists at Bern University measured the day-to-day air quality of a group of pregnant women and measured lung health of their babies at five weeks.

Babies, who had the highest exposure to pollution in the womb, breathed an average of 48 times a minute compared with 42 times of those less exposed and they also had higher levels of exhaled nitric oxide, a marker of airway inflammation.

Those living within 150 metres of a major road were most affected, lead researcher Philipp Latzin told the European Respiratory Society congress in Berlin. Previous studies have only shown lung damage from air pollution in school-aged children. Latzin said he was uncertain about the mechanisms but it is possible that oxidative stress and inflammation in mother's lungs may stifle blood flow to the placenta, reducing nutrient supply.