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Specific guide to this web site for:
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Misadventures:
1. Harvard led MI study
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Cardio.)
3. NEJM
cath study
4. Amer. J. of Cardio.
review of literature
5. ALLHAT
controversy
6. Oat bran study
7. Pregnancy & Alcohol
8. Are Geminis
really
different?
9. Columbia 'Miracle' Study
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Celebrex
Limitations of Meta-Analyses
Large Randomized Clinical
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Tale of Two Large
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Advocate
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Roehm E. Letter, Maternal alcohol consumption and birth weight. JAMA
1985:253:3551
To the Editor.-- In the October 12, 1984 issue of JAMA,
Mills
et al1 have published important prospectively gathered information on
maternal alcohol consumption and its relation to birth weight.
Among their conclusions is that the adjusted odds ratio for
small-for-dates infants is 1.1 for women drinking less than one drink per day
and 1.62 for women drinking one to two drinks per day.
However, when the women are stratified by smoking status, it appears from their
data as presented in Table 5 that the effects of drinking less than one drink
per day or one to two drinks per day for a nonsmoking woman may not be
important. Specifically, the mean
birth weight for nonsmokers is 3,468 grams (nondrinkers), 3,500 grams (less than
one drink per day), and 3,452 grams (one to two drinks per day). Data are given
for the odds ratio of a small-for-gestational-age infant being produced from
different levels of alcohol consumption as a group but not specifically for
nonsmokers.
Since 22,485 of the 31,604 pregnancies in this study were in nonsmokers, this
consideration applies to a sizable portion of those studied and, hence, a group
large enough for subgroup analysis. In addition, the authors have already
analyzed crude birth weight for various levels of alcohol consumption when
stratified by smoking status. Hence,
there is good rationale for the authors to supply further information on the
small-for-gestational-age frequency for the different levels of alcohol
consumption when stratified by smoking status.
This would help clarify further their findings for the large group of
nonsmoking pregnant females.
A somewhat different interpretation of the data might then be made and is as
follows. For nonsmokers, drinking
zero, less than one, or one to two drinks per day has negligible effect on the
fetus size, and possibly on the development of small-for-gestational-age
infants. However, with these lower
levels of alcohol consumption in smokers, there may be an effect on both crude birth
weight and development of small-for-gestational-age infants.
This raises the possibility that there is a negative synergistic effect of
smoking and low-level alcohol consumption on the infants of pregnant females.
Specifically, the decrement in crude mean birth weight for low levels of
alcohol consumption is greater for smokers, suggesting that the combination of
smoking and alcohol consumption is more than simply additive in its negative
effect.
Although consumption of three drinks per day in nonsmoking pregnancies was
associated with a decrease in the crude birth weight, consumption of lesser
amounts of alcohol in the large group of nonsmoking females was without
significant effect. This contrasts
with a possible detrimental effect of low level alcohol consumption in combination with
smoking.
Eric Roehm, M.D.
Web
site author's note: This letter contains considerable speculation.
1. Mills JL, Graubard BI, Harley EE, et al. Maternal alcohol consumption and birth weight:
How much drinking during pregnancy is safe? JAMA 1984:252:1875-1879
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