Birth to 4 Months - Secondhand Smoke
When your baby breathes in tobacco smoke from the air, things happen that you can't see. The baby's heart beat speeds up, blood pressure rises, and dangerous carbon monoxide seeps into his blood. Since babies breathe faster than adults, they breathe in 2-3 times more polluted air per unit of body weight. There is evidence that exposure to smoke may harm your baby's brain development.
Babies of parents who smoke at home or in the car have more ear infections and runny noses, and may develop lung diseases such as bronchitis, asthma and pneumonia. Tobacco smoke increases (doubles) the risk of Sudden Infant Death Syndrome (SIDS).