Kyrklund-Blomberg N B, Cnattingius S
Division of Obstetrics and Gynaecology, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden.
Am J Obstet Gynecol. 1998 Oct;179(4):1051-5. doi: 10.1016/s0002-9378(98)70214-5.
The object was to examine the effects of smoking on spontaneous and induced very and moderately preterm birth (< or = 32 and 33-36 completed weeks' gestation, respectively).
Live singleton births in Sweden, 1991-1993 (n = 311,977), were examined.
Risk of preterm birth consistently increased with amount smoked. Smoking was most heavily associated with increased risks of very preterm birth and spontaneous preterm birth. The highest impact of smoking was seen on risk of spontaneous very preterm birth among women who smoked at least 10 cigarettes/d (odds ratio 1.7). The smoking-related risks of preterm birth remained essentially unchanged after excluding pregnancies with smoking-associated pregnancy complications.
There is a dose-related impact of smoking on risk of preterm birth. The fact that the smoking-related risk of spontaneous preterm birth is more pronounced than that of induced preterm birth suggests that smoking is associated with spontaneous preterm labor.
本研究旨在探讨吸烟对自然早产和诱发早产（分别为妊娠≤32周和33 - 36周）的影响。
对1991 - 1993年瑞典的单胎活产（n = 311,977）进行了调查。
早产风险随着吸烟量的增加而持续上升。吸烟与极早产和自然早产风险增加的关联最为密切。吸烟对每天至少吸10支烟的女性自然极早产风险的影响最大（优势比为1.7）。排除与吸烟相关的妊娠并发症的妊娠后，吸烟相关的早产风险基本保持不变。
吸烟对早产风险有剂量相关的影响。吸烟相关的自然早产风险比诱发早产风险更显著，这一事实表明吸烟与自然早产相关。
