Parents’ smoking is harmful to infants’ health. While it is well established that the fraction of mothers smoking during pregnancy is non-negligible, it is an open question of how many parents actually quit smoking to account for the adverse health effects accruing to their offspring. It is also unknown for how long smoking is reduced after first childbirth. This paper investigates these questions in a longitudinal analysis. The analyzed time period covers smoking patterns several years before childbirth and up to twenty years afterwards. Women’s smoking probability already drops several years before first childbirth and it remains reduced until the first child turns 18 years old. In the second and third trimester of pregnancy, the drop is largest by around 75 percent.

父母吸烟有害于婴儿的健康。众所周知，母亲在怀孕期间吸烟的比例是不可忽略的，但这是一个开放的问题，即有多少父母实际戒烟以解决其后代对健康的不利影响。第一次分娩后减少吸烟时间还不清楚。本文在纵向分析中研究了这些问题。分析的时间段涵盖了分娩前数年和之后二十年的吸烟模式。妇女的吸烟几率在第一次分娩之前已经下降了几年，并且一直下降到第一个孩子年满18岁为止。在怀孕的中期和中期，下降幅度最大，约为75％。