Moderate alcohol drinking and risk of preterm birth.
OBJECTIVE
We have analysed the association between alcohol drinking before and during the three trimesters of pregnancy and risk of preterm birth of babies with normal weight for gestational age or with low weight for gestational age (SGA).


METHODS
Case-control study.


METHODS
General and university hospitals in Italy.


METHODS
Cases were 502 women who delivered preterm births <37 weeks gestation. The controls included 1966 women who gave birth at term (>/=37 weeks of gestation) to healthy infants of normal weight (ie between 10th and 90th centile according to the Italian standard) on randomly selected days at the hospitals where cases had been identified.


METHODS
Interview.


RESULTS
No increased risk of preterm birth was observed in women drinking one or two drinks/die in pregnancy, but three or more drinks/die increased the risk (multivariate odds ratios (OR) 2.0 for >/=3 drinks during the first trimester, 1.8 during the second and 1.9 during the third). When the analysis was conducted separately for preterm births with normal weight or SGA, the increased risk was observed in preterm SGA only (multivariate OR for >/=3 drinks/die during the first trimester=3.6, 95% confidence interval (CI) 1.3-11.1); the estimated multivariate OR for >/=3 drinks/die during the first trimester of preterm babies with normal weight for gestational age was only slightly above unity and not statistically significant (multivariate OR 1.4, 95% CI 0.5-3.7).


CONCLUSIONS
The study shows an increased risk in mothers who drink >/=3 die units alcohol in pregnancy of preterm births.
D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications; D007231:Infant, Newborn; D007234:Infant, Premature; D007236:Infant, Small for Gestational Age; D007407:Interviews as Topic; D007558:Italy / Q000453:epidemiology; D007752:Obstetric Labor, Premature / Q000453:epidemiology* / Q000209:etiology; D016017:Odds Ratio; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular; D011256:Pregnancy Outcome; D011263:Pregnancy Trimester, Third; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects