Health effects of smoking and passive smoking on pregnant women:

-Women who smoke have greater difficulty getting pregnant and have a higher risk of never becoming pregnant.

-Smoking during pregnancy can cause tissue damage in the unborn child, especially in the lungs and brain, and some studies suggest a link between maternal smoking and cleft lip.

-Studies also suggest a link between tobacco use and miscarriages. The carbon monoxide in tobacco smoke can cause the developing baby to not get enough oxygen. Tobacco smoke also contains other chemicals that can harm unborn babies.

Health effects of smoking and passive smoking on babies:

-Mothers who smoke are more likely to deliver their babies prematurely. Premature birth is a leading cause of death, disability, and illness in newborns.

-One in five babies born to mothers who smoked during pregnancy has a low birth weight. Mothers who were exposed to secondhand smoke during pregnancy have a higher risk of low birth weight in their babies. Babies who are born too small or too early are not as healthy.

-Both babies whose mothers smoke during pregnancy and babies exposed to secondhand smoke after birth have a higher risk of dying from sudden infant death syndrome (SIDS) than babies who are not exposed to cigarette smoke.

-Babies whose mothers smoke have about three times the risk of dying from SIDS.

-Babies whose mothers smoke during pregnancy or who are exposed to secondhand smoke after birth have weaker lungs than other babies, which increases the risk for many health problems.

As you said that your wife is a chain smoker then it is a miracle that your baby has been born. At this very crucial moment, you should talk to your wife calmly. Try to make her quit smoking. If possible, you should also try to help her in quitting smoking. You should also try to give her nicotine replacement therapy.