On the Czech set of European Longitudinal Study of Pregnancy and Childhood (ELSPAC), we tried to verify whether it is possible to confirm the results of foreign studies which found out that the both prenatal and postnatal exposure of newborns to chemicals on cigarette smoke could influence the newborns' morbidity in the first six months of their life. Mothers, who served as sources of data about their smoking behaviour during the pregnancy and after the birth as well as information about the health status of the children after the birth (N=3,871) were divided into four groups: 1. women who never smoked (74.3%), 2. women who stopped smoking in pregnancy and started to smoke after delivery (18.3%), 3. women who smoked both during pregnancy and after delivery (7.2%), 4. women who smoked during pregnancy and stopped after delivery. Unfortunatelly, the last group was very small (only seven mothers) and did not allow assessment of exclusively prenatal exposition. Sucklings from Czech ELSPAC set exposed to chemicals in cigarette smoke either only after the birth or also during the prenatal period, showed significantly higher occurence of different symptoms of respiratory tract damages and their complications (like otitis media) when compared to children of non smoking mothers. Due to illnesses during the first six months after the birth, their parents had to look more often for the consultations of physician, including hospitalization. Our results, as well as results of foreign studies, confirm, that smoking of mothers during the pregnancy and after the birth represents significant risk for the first months of life. Illnesses of children in this early period can cause longitudinal consequences which emerge during the childhood as well as in adulthood. They also represent a strong stressogenic factor. Children's health consequences of exposure to cigarette smoke request very often intensive and expensive care within health system. Our results are the same as those of foreign studies and confirm that both prenatal and postnatal exposure to chemicals of cigarette smoke is significant risk factor which negatively influences the health status on the early periods life.