Maternal cigarette smoking and tubal pregnancy.
As part of a case-control study of tubal pregnancy, we sought to evaluate the potential etiologic role of maternal cigarette smoking. Between 1975-1979, 192 women who were treated for a tubal pregnancy in five Seattle hospitals were interviewed with regard to smoking habits and reproductive, contraceptive, and medical histories. For comparison, 459 Seattle-area women who delivered during the same period were also interviewed. Current cigarette smokers had a more than twofold increase in risk of tubal pregnancy (adjusted relative risk 2.2; 95% confidence interval 1.4-3.4) when compared with women who had never smoked. The risk for women who had stopped smoking before conception was 1.6 (95% confidence interval 1.0-2.8). There was no consistent trend between the risk of tubal pregnancy and the duration of smoking, average number of cigarettes smoked per day, age at which a woman began to smoke, pack-years of cigarettes smoked, or (among former smokers) the recency of smoking. Although several sources of bias in the present study may have created a spurious association between cigarette smoking and the occurrence of tubal pregnancy, it could well be that an increased risk of tubal pregnancy is yet another untoward consequence of cigarette smoking.
Chow
W H
WH
Department of Community Health, School of Medicine, Emory University, Atlanta, Georgia.
Daling
J R
JR
Weiss
N S
NS
Voigt
L F
LF
D005260:Female; D006801:Humans; D011247:Pregnancy; D011274:Pregnancy, Tubal / Q000209:etiology*; D012907:Smoking / Q000009:adverse effects*