In addition to the risk of miscarriage, premature birth, and death of the baby in its first year of life, a woman's smoking during pregnancy also has other effects on the baby:
- The growth and development of all unborn babies is impaired if their mothers smoke. On average, birth weight is reduced by about half a pound. This makes little difference to a baby of normal weight, but could be crucial to ones weighing 3 to 4 pounds.
- The development of the brain is also affected. Children whose mothers smoked during pregnancy are on average about one year behind non-exposed children in reading and numerical ability, for example. Loss of a few IQ points may be hardly noticeable to a normally intelligent child or adult, but may be critical for someone on the borderline.
- The child will be more likely to have behavioral problems and hyperactivity.
- Finally, during the first few years of life, children are especially vulnerable to the harmful effects of
passive smokingif their parents smoke. These effects include worsening of asthma, increased frequency of colds and ear infections, and increased risk of sudden infant death syndrome.