吸烟对妊娠有害已被充分证实。吸烟母亲生低体重儿（＜２．５ｋｇ）的比例升高，而且这些婴儿很可能在１岁之内死亡，或易在儿童期发生感染，进入成年期死亡率也比正常者高。研究者随访８７９名缅甸克伦妇女，在怀孕２个月～３个月时列为研究对象直到分娩，每月查一次疟原... Smoking is harmful to pregnancy has been fully confirmed. Smoking mothers have a higher prevalence of low-birth-weight infants (<2.5 kg), and these infants are likely to die within 1 year of age or are susceptible to infection during childhood, with higher rates of death into adulthood than normal. The researchers followed 879 Burmese karen women who were enrolled in the study from 2 months to 3 months of pregnancy until delivery and once a month.