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HOW THE ANTI-SMOKERS LIE ABOUT SMOKING AND PREGNANCY

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"Acute chorioamnionitis is the largest contributor to the poor pregnancy outcomes of black women and women who have low socioeconomic status," and it is "the most common cause of preterm labor wherever it has been studied."(RL Naeye. Acute chorioamnionitis and the disorders that produce placental insufficiency. In: Monographs in Pathology No.33, Pathology of Reproductive Failure. FT Kraus et al, eds. Williams and Wilkins 1991. Ch 10, pp 286-307).
 

Smokers' lower average socioeconomic status results in serious confounding, because chorioamnionitis is the most commonly missed perinatal diagnosis. Only 1/10 of affected mothers show symptoms, and only 1/4 of fatal cases could be diagnosed without histopathological analysis. (RL Naeye. Editorial. The investigation of perinatal deaths. NEJM 1983;309(10):611-612).
 

The authors of anti-smoking studies have been diagnostically negligent: "Those who have analyzed [stillbirths and neonatal deaths] rarely have taken the initiating disorders that led to these deaths into consideration, in part because identifying these underlying disorders usually requires a placental examination." They don't do such an examination, and they never admit that this is inadequate. They pretend it's good enough to shovel birthweight and gestation data into a computer program and calculate odds ratios, and nobody calls them on it.
 

Naeye: "We recently found no significant association between maternal smoking and either stillbirths or neonatal deaths when information about the underlying disorders, obtained from placental examinations, was incorporated into the analysis. Similar analyses found no correlation between maternal smoking and preterm birth. The most frequent initiating causes of preterm birth, stillbirth, and neonatal death are acute chorioamnionitis, disorders that produce chronic low blood flow from the uterus to the placenta, and major congenital malformations. There is no credible evidence that cigarette smoking has a role in the genesis of any of these disorders." Naeye's study population is the 56,000+ pregnancies of the Collaborative Perinatal Study.(RL Naeye. Disorders of the placenta, fetus, and neonate, diagnosis and clinical significance. New York: CV Mosby Co., 1992). So-called smoking- attributable gestational shortening is actually dependent on higher rates of intraamniotic infection in smokers than in non-smokers.
 

Sterile nonbacterial substances or viruses do not cause chorioamnion- itis. It is caused by bacteria or mycoplasmas, many of them anaerobic types which are difficult to grow or identify using older techniques. And, "Because the frequency of preterm births has hardly changed in the United States during the past three decades, it is unlikely that anything currently being done in the health care system is preventing these infections." Note that this is despite the purported benefits of decreased smoking rates.
 

The infection weakens the fetal membranes and causes their premature rupture. In the Collaborative Study, most cases were due to chorioamnionitis. Pneumonia in newborns is almost invariably a consequence of intraamniotic infection. Exposed neonates are also at greater risk of septicemia, and more rarely otitis media, meningitis, and septic arthritis, which anti-smokers have also attempted to blame on maternal smoking.
 

Chorioamnionitis causes villous edema, which results in hypoxia. Low Apgar scores and respiratory distress correlate with the amount of edema. Preterm infants without edema do almost as well as healthy term infants (The clinical significance of placental villous edema. RL Naeye et al. Pediatrics 1983;71(4):588-594). Poor placental circulation alone, such as that caused by maternal hypertension, does not cause edema, and, "in twin placentas with two completely separate placental circulations the edema was much more severe on the side with the chorioamnionitis" than the unaffected side, proving that the edema originated with the infected fetus, not in the mother's circulation.
 

Low birth weight in the absence of chorioamnionitis or other actual disease, is of negligible clinical significance. But anti-smoker cost estimates attribute extra costs to what are actually healthy births without such costs by statistical flim-flam: They compare average costs of <2500g births versus >2500g births, estimate the number of extra "smoking-related" lower-weight births, and multiply them by the cost difference.
 

Anti-smokers also falsely blame other poor birth outcomes on maternal smoking. Respiratory Distress Syndrome should not be attributed to smoking because most studies find less RDS among smokers' babies (E Lieberman, J Torday et al. Association of intrauterine cigarette smoke exposure with indices of fetal lung maturation. Obstet Gynecol 1992;79:564-570).
 

Sudden Infant Death Syndrome is not even a specific disease, but just an unexplained death. The risk factors (other than sleeping position) are identical with socioeconomic disadvantage. In The Netherlands, SIDS deaths increased by 10 times between 1971 and 1985, despite declines in maternal smoking during this period, because of a switch in the customary sleeping position (AC Engelberts, GA de Jonge. Choice of sleeping position for infants: possible association with cot death. Arch Dis Childhood 1990;65:462-467.) After publicity against the prone sleeping position, death rates fell 37% in just one year. 

So-called maternal smoking harms are really medical deficiencies that are maliciously being blamed on the victims themselves.
 

Courtesy of Carol Thompson 08/23/93
Smokers' Rights Action Group
P.O. Box 259575
Madison, WI 53725-9575
Phone: 608-249-4568