Cigarette, alcohol, and coffee consumption and prematurity.

Abstract

Pubic Health Briiefs ences might thus be related to biases specific to the study designs.The small risk associated with coffee consumption might be explained by residual confounding. If caffeine were a causal agent, we would have suffered loss of power from lack of information on other caffeine intake. However, nutrition survey data show total caffeine intake and coffee consumption to be highly correlated (r = .98) in Quebec women (Health and Welfare Canada, personal communication). Evidence of an association between caffeine consumption and early fetal loss has been reported,15 but no such association has been reported, so far aswe are aware, with spontaneous abortion.If the observed associations were causal, cigarettes accounted for about 11% of all spontaneous abortions (40% in women who smoked 20 or more cigarettes per day), alcohol consumption for about 5% (45% in women drinking 3 or more drinks per day) and coffee for about 2% (16% in women drinking 10 cups per day).

Coffee drinking and risk of preterm birth

“…Most previous studies, which took some confounding factors into account, found no association (Fenster et al, 1991;McDonald et al, 1992;Fortier et al, 1993;Pastore and Savitz, 1995;Peacock et al, 1995). We found a modest positive association between tea consumption and risk of SGA preterm birth, but this was not significant.…”

“…Studies on caffeine and preterm births have produced conflicting results (Fenster et al, 1991;Olsen et al 1991;McDonald et al, 1992;Fortier et al, 1993;Pastore and Savitz, 1995;Peacock et al, 1995;Eskenazi et al, 1999). Most of these studies are limited because lack of the information about multiple sources of caffeine and many studies did not control for any confounders.…”

Moderate alcohol drinking and risk of preterm birth

“…There are consistent findings on the association between low birth weight and alcohol intake: studies on the issue have shown a direct association (Windham et al, 1995;McDonald et al, 1992). Our results give support to this finding.…”

“…Other reports showed an increased risk of preterm birth also for moderate alcohol drinking. For example, a moderate increased risk of delivery of preterm babies with low weight for gestational age at birth was found to be associated with alcohol drinking in a Canadian study (McDonald et al, 1992). A prospective investigation based on 2714 single live births conducted in the US during 1988-1992 indicated an increased risk of preterm birth, but not of small weight for gestational age (SGA) (Lundsberg et al, 1997).…”

Is low birth weight in the causal pathway of the association between maternal smoking in pregnancy and higher BMI in the offspring?

“…Low birth weight is another well-established adverse effect of maternal smoking in pregnancy (13)(14)(15). Infants with low birth weight are known to catch up their weight and to a smaller extent their height deficit within the first two years of life (16,17).…”