Smoking during pregnancy is a well-recognized public health problem and several associated variables to smoking have been identified such as low socioeconomic status, low educational attainment, low social support, younger age and unplanned pregnancy. The purpose of this research was to further examine possible risk factors associated with smoking in pregnancy. One hundred and nineteen pregnant women who were having their first babies had been recruited in early pregnancy from a General Hospital Obstetric Service and were followed up throughout the pregnancy and then until 4 years after the birth of the baby. The findings of this longitudinal study have already been reported in relation to maternal postnatal depression and to child development and in the analyses of smoking behavior which are reported here, it was possible to control for several confounding variables in the search for possible risk factors. Women who smoked during pregnancy were more likely to have had previous miscarriages and terminations and to have taken longer to conceive this pregnancy. They were also more likely to report marital difficulties and more likely to physically discipline their 1-year-old infants. These results point to a possible different perspective in trying to understand this intransigent unhealthy behavior.