Obstetric and perinatal effects of active and/or passive smoking during pregnancy

The Effect of Active and Passive Maternal Smoking During Pregnancy on the Uterine Artery Blood Flow and Obstetric Outcomes: A Prospective Study

BACKGROUND AND AIM

Maternal smoking is associated with an increased risk of obstetric and neonatal complications during pregnancy. We aimed to investigate the effects of active and passive smoking on fetal-maternal blood flow and fetal complications in mid-trimester pregnant women.

METHODS

This prospective study was conducted at Zekai Tahir Burak Women's Research and Training Hospital and included women who were 20 to 22 weeks old, with no fetal anomalies, and with a singleton pregnancy. The data used in the analysis were obtained from a total of 168 pregnant women (50 smokers, 50 passive smokers, and 68 non-smokers). Starting from their 20^th week of pregnancy, the women were examined at least once in each trimester. Fetal and maternal pregnancy results were evaluated. Fetal biometry, umbilical, and uterine artery Doppler ultrasonography were performed. To evaluate the flow in these veins, the pulsatility index, resistance index, and systole/diastole (S/D) ratio were performed.

RESULTS

The mean age of study patients was 25.06 ± 4.36 years and the mean gestational week was 20.03 ± 0.6 weeks. In terms of the umbilical artery pulsatility index (UMBAPI), umbilical artery systolic/diastolic ratio (UMBAS/D),uterine artery resistance index (UARI), uterine artery pulsatility index (UAPI), and uterine artery systolic/diastolic ratio (UAS/D) levels, the mean value of the smoker group was significantly higher compared to the non-smoker group (p<0.001, p=0.043, p=0.021, p=0.020, and p=0.037, respectively). The birth weight of the fetus was significantly lower in the active and passive smoker groups than in the non-smoker group (p=0.009 and p=0.006, respectively). The number of patients diagnosed with intrauterine growth restriction (IUGR) and oligohydramnios were significantly higher in the smoker group than in the passive smoker and non-smoker groups (p=0.003 and p<0.001, respectively). The risk of low birth weight (OR, (95% CI): 3.38 (2.05 - 5.57); p=0.024), oligohydramnios (OR (95% CI): 13.44 (5.22 - 34.57); p=0.001), IUGR (OR (95% CI): 9.33 (4.50 - 19.33); p=0.001), and preterm birth (OR (95% CI): 4.56 (1.25 - 17.32); p=0.001) increased significantly in the active and passive cigarette exposure groups, compared to the non-smokers.

CONCLUSION

During pregnancy, both smoking and passive exposure to cigarette smoke adversely affect the fetus and the newborn. Uterine and umbilical artery Doppler measurements in pregnant women who smoke are significantly higher than the pregnant women who do not smoke.

Maternal smoking status during pregnancy and low birth weight in offspring: systematic review and meta-analysis of 55 cohort studies published from 1986 to 2020

BACKGROUND

Maternal smoking during pregnancy may be associated with low birth weight (LBW) in offspring and global risk estimates have not been summarized previously. We aimed to systematically explore evidence regarding maternal smoking and the LBW risk in offspring globally and examine possible causes of heterogeneity across relevant studies.

METHODS

Comprehensive search of PubMed, Ovid Embase, Ovid Medline (R), and Web of science from inception until October 2021 was carried out. A random-effects meta-analysis was used to estimate the pooled odds ratio (OR) and corresponding 95% confidence interval (CI). Restricted cubic spline analysis with three knots was used to further examine the dose-response relationship.

RESULTS

Literature searches yielded 4940 articles, of which 53 met inclusion criteria (comprising 55 independent studies). Maternal smoking during pregnancy was significantly associated with the risk of LBW in offspring (OR = 1.89, 95% CI = 1.80-1.98). Furthermore, an obvious dose-response relationship between the amount of cigarettes daily smoked in pregnancy and the risk of LBW in offspring was observed. The results of subgroup analyses indicated that the risk of maternal smoking on LBW was larger in more recently conducted studies (P = 0.020) and longer period of active smoking during pregnancy (P = 0.002). No evidence of publication bias was found.

CONCLUSIONS

In summary, maternal smoking in pregnancy was significantly associated with a higher risk of LBW in offspring on a global scale. The risk of maternal smoking on infant LBW seems to be increasing over time, and was higher with longer smoking duration throughout pregnancy and more cigarettes smoked daily.

Assessment of the Relationship Between Smoking and Depression in Pregnant Women

Smoking during pregnancy has negative effects on both maternal and fetal health. One of these negative maternal effects is the potential for depression. A high rate of cigarette smoking in pregnancy is an important public health issue since it affects not only the pregnant woman but also the newborn and its healthy development. The aim of this study is to investigate the relationship between smoking, influencing factors, and depression prevalence in pregnant Syrian refugees and pregnant citizens of the Republic of Turkey (TR). Pregnant citizens in the TR and pregnant Syrian refugees who were registered at health centers between 15.04.2017 and 15.10.2017 in the border city of Ceylanpınar in the Province of Şanlıurfa in Syria were visited in their living areas in the district center and at a tent village, respectively. A total of 414 pregnant women agreed to participate in the study and were included in the survey. To collect data for the cross-sectional study, a sociodemographic and pregnancy characteristics questionnaire was used, in addition to the Fageström Test for Nicotine Dependence (FTND) and the Beck Depression Inventory (BDI). The rate of smoking in all pregnant women was determined to be 49.3% (n = 204) before pregnancy and 37.9% (n = 157) during pregnancy. A statistically significant difference was found between age groups and educational status in relation to smoking status (p = 0.005, p = 0.001). There was also a statistically significant difference between the smoking status of pregnant women and that of their partners and family members (p = 0.001, p = 0.002). The percentage of pregnant women who were passive smokers was 80.2% (n = 332), and a statistically significant difference was found between passive smoking and smoking status (Fisher; 0.000). The presence of risk for depression was detected in 49.8% (n = 206) of all pregnant women surveyed; the rate of depression risk was 50.5% (n = 104) in pregnant TR citizens and 49.5% (n = 102) in pregnant refugees, with no significant difference between the two groups. There was a statistically significant difference between smoking status in pregnancy and the presence of depression risk (p = 0.001). 32.5% of pregnant women were highly nicotine dependent. A moderate positive correlation was determined between the FTND and BDI scores of pregnant women (r = 0.346; p = 0.001). It was found that one-third of all pregnant women smoked and that one of every two showed a risk for depression. A statistically significant correlation was found between smoking status and risk for depression. No statistically significant difference was determined between the two groups, despite high levels of smoking, nicotine dependence, and depression in both. These data suggest the need to develop new preventive strategies in regard to smoking among pregnant women.

Air pollution and low birth weight in an industrialized city in Southeastern Brazil, 2003-2006

ABSTRACT: Introduction: Birth weight is an important indicator of several conditions that manifest earlier (as fetal and neonatal mortality and morbidity, inhibited growth and cognitive development) and later in life such as chronic diseases. Air pollution has been associated with adverse pregnancy outcomes. Objective: Retrospective cohort study investigated the association between low birth weight (LBW) and maternal exposure to air pollutants in Volta Redonda city, Rio de Janeiro, Brazil, from 2003 to 2006. Methods: Birth data was obtained from Brazilian Information System. Exposure information (O3, PM10, temperature and humidity) was provided by Governmental Air Quality Monitoring System. Linear and Logistic models, adjusted for sex, type of pregnancy, prenatal care, place of birth, maternal age, parity, education, congenital anomalies and weather variables were employed. Results: Low birth weight (LBW) represented 9.1% of all newborns (13,660). For an interquartile range increase in PM10 it was found OR2 ndTrimester = 1.06 (95%CI 1.02 - 1.10), OR3 rdTrimester = 1.06 (95%CI 1.02 - 1.10) and, in O3 it was found OR2 ndTrimester = 1.03 (95%CI 1.01 - 1.04), OR3 rdTrimester = 1.03 (95%CI 1.02 - 1.04). The dose-response relationship and a reduction in birth weight of 31.11 g (95%CI -56.64 - -5.58) was observed in the third trimester of pregnancy due to an interquartile increase of O3. Conclusion: This study suggests that exposures to PM10 and O3, even being below the Brazilian air quality standards, contribute to risks of low birth weight.

Investigating the Effects of Exposure to Waterpipe Smoke on Pregnancy Outcomes Using an Animal Model

INTRODUCTION

In recent years, waterpipe tobacco smoking has been increasing in popularity all over the world. In this study, we explored effects of waterpipe smoking on pregnancy outcomes in rats.

METHODS

Animals were exposed to waterpipe tobacco smoking using a whole body exposure system 2 hours per day during pregnancy. A control group was exposed to fresh air only.

RESULTS

The results showed significant association between exposure to waterpipe smoke during pregnancy and low birth weight (P < .01) and neonatal death (P < .01). In addition, the rate of growth of offspring of the waterpipe group was significantly lower than that of control group as measured by body weight gain during the first 3 months of life (P < .001). No effect was found for waterpipe smoking on mean number of progeny and male to female ratio among offspring.

CONCLUSION

Waterpipe smoking is associated with adverse effects on pregnancy outcomes.

IMPLICATIONS

In this study, we investigated for the first time the effect of waterpipe smoking on pregnancy outcomes using animal model. The results clearly showed that waterpipe smoking is associated with adverse effects on pregnancy outcomes that include low birth weigh, neonatal survival, and growth retardation.

Systematic review and meta-analysis of miscarriage and maternal exposure to tobacco smoke during pregnancy

We conducted a systematic review and meta-analysis to characterize the relationship between smoking and miscarriage. We searched the PubMed database (1956-August 31, 2011) using keywords and conducted manual reference searches of included articles and reports of the US Surgeon General. The full text of 1,706 articles was reviewed, and 98 articles that examined the association between active or passive smoking and miscarriage were included in the meta-analysis. Data were abstracted by 2 reviewers. Any active smoking was associated with increased risk of miscarriage (summary relative risk ratio = 1.23, 95% confidence interval (CI): 1.16, 1.30; n = 50 studies), and this risk was greater when the smoking exposure was specifically defined as during the pregnancy in which miscarriage risk was measured (summary relative risk ratio = 1.32, 95% CI: 1.21, 1.44; n = 25 studies). The risk of miscarriage increased with the amount smoked (1% increase in relative risk per cigarette smoked per day). Secondhand smoke exposure during pregnancy increased the risk of miscarriage by 11% (95% CI: 0.95, 1.31; n = 17 studies). Biases in study publication, design, and analysis did not significantly affect the results. This finding strengthens the evidence that women should not smoke while pregnant, and all women of reproductive age should be warned that smoking increases the risk of miscarriage.

Associations of lifetime active and passive smoking with spontaneous abortion, stillbirth and tubal ectopic pregnancy: a cross-sectional analysis of historical data from the Women's Health Initiative

OBJECTIVE

To examine the associations between tobacco exposure and adverse pregnancy outcomes using quantitative measures of lifetime active smoking and secondhand smoke (SHS) exposure.

METHODS

Historical reproductive data on 80 762 women who participated in the Women's Health Initiative Observational Study were examined with a cross-sectional analysis. We assessed self-reported lifetime active and passive tobacco smoke exposure, self-reported spontaneous abortions, stillbirths and ectopic pregnancies.

RESULTS

When compared with never-smoking women, participants who were ever active smokers during their reproductive years had ORs (OR) of 1.16 (95% CI 1.08 to 1.26) for 1 or more spontaneous abortions, 1.44 (95% CI 1.20 to 1.73) for 1 or more stillbirths, and 1.43 (95% CI 1.10 to 1.86) for 1 or more ectopic pregnancies. Never-smoking women participants with the highest levels of lifetime SHS exposure, including childhood >10 years, adult home >20 years and adult work exposure >10 years, when compared with never-smoking women with no SHS exposure had adjusted ORs of 1.17 (95% CI 1.05 to 1.30) for spontaneous abortion, 1.55 (95% CI 1.21 to 1.97) for stillbirth, and 1.61 (95% CI 1.16 to 2.24) for ectopic pregnancy.

CONCLUSIONS

Women who were ever-smokers during their reproductive years had significantly greater estimates of risk for spontaneous abortion, stillbirth and tubal ectopic pregnancy. Never-smoking women with the highest levels of lifetime exposure to SHS had significantly increased estimates of risk for spontaneous abortion, stillbirth and tubal ectopic pregnancy.

Influence of CYP2A6*4 genotypes on maternal serum cotinine among Chinese nonsmoking pregnant women

INTRODUCTION

Serum cotinine is a common biomarker for smoking and secondhand smoke (SHS) exposure, but it can be affected by the activity of nicotine-metabolizing enzymes. This study investigated the influence of CYP2A6*4 genotypes on serum cotinine among nonsmoking pregnant women.

METHODS

We analyzed the data from 545 Chinese nonsmoking pregnant women in a case-control study on SHS exposure and birth outcomes in southern China. Participants self-reported their status and duration of SHS exposure during pregnancy right after delivery in hospital. Research staff used polymerase chain reaction to genotype CYP2A6*4 and enzyme-linked immunosorbent assay to measure cotinine levels in maternal serum samples collected before delivery. We stratified women by their self-reported SHS exposure status and CYP2A6*4 genotypes and then compared their median levels of serum cotinine.

RESULTS

Among women who self-reported non-SHS exposure (n = 317), the median serum cotinine levels were 2.83ng/ml for those with CYP2A6*1/*1 genotype, 1.39ng/ml for CYP2A6*1/*4, and 0.77ng/ml for CYP2A6*4/*4, respectively. Among women who self-reported SHS exposure (n = 228), the median cotinine levels were 3.32ng/ml for those with CYP2A6*1/*1 genotype, 2.38ng/ml for CYP2A6*1/*4, and 1.56ng/ml for CYP2A6*4/*4, respectively. Strikingly, self-reported SHS-exposed women with CYP2A6*1/*4 or CYP2A6*4/*4 genotype had significantly lower (rather than higher) median cotinine levels than self-reported non-SHS-exposed women with CYP2A6*1/*1 genotype (p = .012).

CONCLUSIONS

CYP2A6*4 genotype is associated with lower serum cotinine among Chinese nonsmoking pregnant women. Measuring CYP2A6*4 genotype may help to improve the validity of SHS exposure measurement by serum cotinine in pregnant women and possibly also in other nonpregnant populations.

Risk factors identification in children with speech disorders: pilot study

PURPOSE: To identify the main risk factors related to children and their parents, associated with speech and language disorders. METHODS: A prospective descriptive study conducted with 170 children and their parents assisted at a school clinic in the period between March 2010 and July 2012. A protocol was developed for this study in order to identify risk factors for language and speech disorders. Data were tabulated and analyzed using descriptive and inferential statistics by the Χ2 and Student' s t-test . RESULTS: The demographic profile is composed of male children aged between 4 and 5 years old, ethnicity declared by parents as being white, residents of the western region of the city of São Paulo, and whose parents had completed high school. The factors related to family and considered as risks for language impairment were being an only child and having a family history of speech and language disorders. As for the children' s health, prematurity, hospitalization for a long period, and the presence of deleterious oral habits were also considered as risk factors. CONCLUSION: The protocol allows establishing the main risk factors related to children with speech and language disorders. It is suggested that children who present with one or more of the aforementioned risk factors should be regularly monitored for speech and language development and, if necessary, referred for early intervention.

Smoking and adverse maternal and child health outcomes in Brazil

INTRODUCTION

Numerous studies from high-income countries document the causal relationship between cigarette smoking during pregnancy and adverse maternal and child health (MCH) outcomes. Less research has been conducted in low and middle income countries, but a burgeoning literature can be found for Brazil.

METHODS

We review Brazilian studies of the prevalence of maternal smoking, the relative risk of smoking-attributable adverse MCH outcomes, and present new estimates for these outcomes, using the attributable fraction method.

RESULTS

We found that Brazilian studies of the relative risks of smoking-attributable adverse MCH outcomes were broadly consistent with previous reviews. Based on a comparison of maternal smoking over time, smoking during pregnancy has declined by about 50% over the last 20 years in Brazil. For 2008, we estimate that 5,352 cases of spontaneous abortion, 10,929 cases of preterm birth, 20,717 cases of low birth weight, and 29 cases of sudden infant death syndrome are attributable to maternal smoking. Between 1989 and 2008, the percent of smoking-attributable adverse MCH outcomes in Brazil was at least halved.

CONCLUSIONS

The results show that over a 20-year period, during which Brazil implemented numerous effective tobacco control measures, the country experienced a dramatic decrease in both maternal smoking prevalence and smoking-attributable adverse MCH outcomes. Countries that implement effective tobacco control measures can expect to reduce both maternal smoking and adverse MCH outcomes, thereby improving the public health.

Exposure of pregnant women to waterpipe and cigarette smoke

INTRODUCTION

Throughout the Eastern Mediterranean region, tobacco is used primarily in 2 forms: cigarette smoking and waterpipe smoking. Despite the fact that tobacco use is considered as a global public health threat, waterpipe smoking is reported to be growing in popularity, particularly among women. The objectives of this study are to determine the prevalence and patterns of cigarette, waterpipe, and passive smoking among pregnant women in Jordan, and to assess their perception of harmful effects of cigarette and waterpipe smoking.

METHODS

A total of 500 pregnant women were randomly recruited from maternity clinics in North and Middle of Jordan and surveyed regarding exposure to waterpipe tobacco and cigarette smoking.

RESULTS

The results showed that 7.9% of women were current cigarette smokers and 8.7% were current waterpipe smokers. About 82.4% of all women reported that they are exposed to cigarette smoke and 32.8% reported that they are exposed to waterpipe smoke. The most common place where women are exposed to cigarette and waterpipe smoke was their house (50.4% and 48.7%, respectively) followed by public places (31.4% and 21.4%, respectively). In addition, the husband was the main source for exposure to cigarette and waterpipe smoke (48.5% and 42.7%, respectively). Approximately, 74% of women believed that cigarette smoking is addictive, whereas only 55.1% reported that waterpipe smoking leads to addiction.

CONCLUSIONS

Exposure of pregnant women to tobacco smoke is a public health problem in Jordan that requires immediate action.

Umbilical cord serum erythropoietin levels and maternal smoking in pregnancy

Objective. To evaluate the effect of maternal smoking during pregnancy on levels of umbilical cord erythropoietin. Methods. Erythropoietin levels were measured in umbilical cord sera of 60 newborns who were delivered vaginally at term. There were 20 (33%) smoking and 40 (67%) nonsmoking mothers. Results. Mean cord serum erythropoietin levels were significantly lower in the nonsmokers (nonsmokers, 24 ± 9 IU/L; smokers, 61 ± 46 IU/L; P < .001). There was a significant positive correlation between the number of cigarettes smoked per day and cord serum erythropoietin levels (r, 0.58; P ≤ .05). Conclusions. Smoking during pregnancy is associated with increased levels of umbilical cord erythropoietin at birth. This may indicate a risk of fetal hypoxia and growth restriction. Education and encouragement of cessation of smoking during pregnancy are important to avoid associated fetal and maternal morbidity and mortality.

The association between second hand smoke and low birth weight and preterm delivery

To determine the association between maternal exposure to SHS and low birth weight and preterm delivery. This cross-sectional study was carried out in the four main governmental hospitals dealing with deliveries in the north of Jordan. A consecutive 8,490 women who delivered in these hospitals between April 2007 and September 2007 were included in the study after excluding those who reported active smoking during the current pregnancy. Pre-structured questionnaire and review of hospital records were used to collect data about maternal background, obstetric history, medical history, and data related to second hand smoke exposure. Overall, 13.8% of women gave birth to a preterm baby and 10.0% gave birth to a low birth weight baby. About 12.6% of women who were exposed to SHS delivered low birth weight babies compared to 7.7% for non exposed women. The rate of preterm delivery among the exposed group was significantly higher than that among the non-exposed group (17.2 vs. 10.6%). In the multivariate analysis, exposure to SHS during pregnancy was significantly associated with increased odds of low birth weight (OR = 1.56 (95% CI 1.31, 1.89)) and preterm delivery (OR = 1.61 (95% CI: 1.30, 1.99)). Exposure of women to SHS during pregnancy is associated with increased odds of low birth weight and preterm delivery. Health care professionals should carry out educational programs to increase awareness and understanding of pregnant women and their husbands about the harmful effects of second hand smoke on birth outcomes.

Secondhand smoke and adverse fetal outcomes in nonsmoking pregnant women: a meta-analysis

OBJECTIVE

To determine the risk of adverse fetal outcomes of secondhand smoke exposure in nonsmoking pregnant women.

METHODS

This was a systematic review and meta-analysis in accordance with Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. We searched Medline and Embase (to March 2009) and reference lists for eligible studies; no language restrictions were imposed. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were estimated by using random-effect models. Our search was for epidemiologic studies of maternal exposure to secondhand smoke during pregnancy in nonsmoking pregnant women. The main outcome measures were spontaneous abortion, perinatal and neonatal death, stillbirth, and congenital malformations.

RESULTS

We identified 19 studies that assessed the effects of secondhand smoke exposure in nonsmoking pregnant women. We found no evidence of a statistically significant effect of secondhand smoke exposure on the risk of spontaneous abortion (OR: 1.17 [95% CI: 0.88-1.54]; 6 studies). However, secondhand smoke exposure significantly increased the risk of stillbirth (OR: 1.23 [95% CI: 1.09-1.38]; 4 studies) and congenital malformation (OR: 1.13 [95% CI: 1.01-1.26]; 7 studies), although none of the associations with specific congenital abnormalities were individually significant. Secondhand smoke exposure had no significant effect on perinatal or neonatal death.

CONCLUSIONS

Pregnant women who are exposed to secondhand smoke are estimated to be 23% more likely to experience stillbirth and 13% more likely give birth to a child with a congenital malformation. Because the timing and mechanism of this effect is not clear, it is important to prevent secondhand smoke exposure in women before and during pregnancy.

Environmental tobacco smoke exposure and perinatal outcomes: a systematic review and meta-analyses

BACKGROUND

While active maternal tobacco smoking has well established adverse perinatal outcomes, the effects of passive maternal smoking, also called environmental tobacco exposure (ETS), are less well studied and less consistent.

OBJECTIVE

To determine to the effect of ETS on perinatal outcomes.

SEARCH STRATEGY

Medline, EMBASE and reference lists were searched.

SELECTION CRITERIA

Studies comparing ETS-exposed pregnant women with those unexposed which adequately addressed active maternal smoking.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed titles, abstracts, full studies, extracted data and assessed quality. Dichotomous data were pooled using odds ratios (OR) and continuous data with weighted mean differences (WMD) using a random effects model.

MAIN RESULTS

Seventy-six articles were included with a total of 48,439 ETS-exposed women and 90,918 unexposed women. ETS-exposed infants weighed less [WMD -60 g, 95% confidence interval (CI) -80 to -39 g], with a trend towards increased low birthweight (LBW, < 2,500 g; RR 1.16; 95% CI 0.99-1.36), although the duration of gestation and preterm delivery were similar (WMD 0.02 weeks, 95% CI -0.09 to 0.12 weeks and RR 1.07; 95% CI 0.93-1.22). ETS-exposed infants had longer infant lengths (1.75 cm; 95% CI 1.37-2.12 cm), increased risks of congenital anomalies (OR 1.17; 95% CI 1.03-1.34) and a trend towards smaller head circumferences (-0.11 cm; 95% CI -0.22 to 0.01 cm).

CONCLUSIONS

ETS-exposed women have increased risks of infants with lower birthweight, congenital anomalies, longer lengths, and trends towards smaller head circumferences and LBW.

Avaliação da dilatação máxima da artéria braquial em gestantes e não gestantes, fumantes e não fumantes

OBJETIVO: Avaliar, por meio da dilatação mediada por fluxo da artéria braquial, em que tempo ocorre a máxima dilatação da artéria braquial e se existe diferença nesta avaliação ao comparar mulheres gestantes e não gestantes, fumantes e não fumantes. MATERIAIS E MÉTODOS: Estudo transversal, no qual o diâmetro da artéria braquial foi avaliado em quatro tempos após estímulo pressórico (30, 60, 90 e 120 segundos) em quatro grupos de mulheres entre 20 e 30 anos de idade assim distribuídos: mulheres gestantes entre 24 e 28 semanas de idade gestacional não fumantes (n = 47) e fumantes (n = 33), e mulheres não gestantes não fumantes (n = 34) e fumantes (n = 19). RESULTADOS: A avaliação da dilatação da artéria braquial nos diferentes tempos após o estímulo pressórico foi máxima para todos os grupos no tempo "60 segundos" após a desinsuflação (p < 0,01). A dilatação mediada por fluxo da artéria braquial foi maior entre as mulheres gestantes não fumantes em comparação às fumantes (p = 0,03), assim como no grupo de mulheres não gestantes não fumantes em comparação às fumantes (p = 0,03). CONCLUSÃO: O hábito de fumar não interferiu no tempo em que ocorre a máxima dilatação da artéria braquial.

[Chronic obstructive pulmonary disease - a review]

COPD is a preventable and treatable disease caused by exposure to tobacco smoke and poisonous gases. It is characterised by progressive obstruction of the airflow, irreversible once lesions occur in the parenchyma. This article aims to systematically review the disease and its treatment.

DISCUSSION

Smoking is the main cause of COPD and leads to decreased oxygenation via lung hyperinflation with reduced airflow as a systemic inflammatory process. This reduces resistance to fatigue of the skeletal musculature, leading to hypoxemia, decreased peripheral blood flow and also miscarriages and premature births. Inflammatory markers such as interleukins and TNF-alpha maintain the systemic picture. While smoking cessation improves hypoxemia and exercise intolerance, it does not repair damaged tissue. COPD is a serious disease which can be avoided by a wider understanding by the population of the harm smoking causes.

Prevalência de tabagismo e consumo de bebida alcoólica em mães de lactentes menores de seis meses de idade

OBJETIVO: Conhecer a prevalência de tabagismo e consumo de bebida alcoólica em mães de lactentes menores de seis meses de idade. MÉTODOS: Estudo transversal e descritivo com mães de crianças com idade entre zero e seis meses completos, matriculadas em programas de puericultura das Unidades Básicas de Saúde da cidade de Ribeirão Preto (SP), ligadas aos seis Centros de Saúde Escola da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo. Foi aplicado um questionário em que constavam informações como idade materna, grau de escolaridade, paridade, ocupação, tempo de aleitamento materno exclusivo e complementado, consumo de bebidas alcoólicas e cigarros e existência de algum tabagista no domicílio. RESULTADOS: Foram entrevistadas 504 mulheres; 324 (64,3%) tinham algum contato com cigarro sendo 97 (19,2%) tabagistas ativas, 142 (28,2%) tabagistas passivas e 85 (16,8%) tabagistas ativas e passivas. Dentre as 97 tabagistas ativas, 78 (80,4%) estavam amamentando. Também estavam amamentando 118 (83,1%) das 142 mães tabagistas passivas. Quanto às bebidas alcoólicas, 56 (11,1%) mães responderam que as consumiam e, destas, 45 (80,3%) estavam amamentando. Quinze (26,8%) mães que consumiam bebidas alcoólicas também eram tabagistas. CONCLUSÕES: O estudo encontrou alta prevalência de mães com algum tipo de contato com tabagismo e que consumiam bebidas alcoólicas, sendo imprescindível investir na prevenção dessas práticas nos programas de assistência pré-natal e de puericultura.

Effects of cigarette smoke exposure on pregnancy outcome and offspring of diabetic rats

A total of 52 female Wistar rats were distributed into four groups: non-diabetic (G1) and diabetic (G2) exposed to filtered air; non-diabetic (G3) and diabetic (G4) exposed to cigarette smoke. Diabetes was induced by streptozotocin (40 mg/kg bodyweight, i.v.). Rats were exposed, for 30 min, to filtered air (control) or to tobacco smoke generated from 10 cigarettes, twice a day, for 2 months. At the end of the 2-month exposure, at day 21 of pregnancy, each rat was anesthetized and humanely killed for laparotomy. Uterine horns were exposed for reproductive performance analysis, fetal and placental weights and placental index. Maternal and fetal data were analysed by ANOVA followed by the Student Newman-Keuls test. Fetal weight classification was assessed by Fisher's exact test. Diabetes and cigarette smoke caused placentomegaly (G4 = 0.65 +/- 0.19 g versus G1 = 0.49 +/- 0.03 g, P < 0.05), increased placental index (G4 = 0.13 +/- 0.03 versus G1 = 0.09 +/- 0.00, P < 0.05) and small fetus rates for pregnancy age (G4 = 88% versus G1 = 23.2%, P < 0.05). These observations show the importance of encouraging pregnant women to attempt cessation of smoking.

Meconium nicotine and metabolites by liquid chromatography-tandem mass spectrometry: differentiation of passive and nonexposure and correlation with neonatal outcome measures

BACKGROUND

Meconium analysis is a diagnostically sensitive and objective alternative to maternal self-report for detecting prenatal tobacco exposure. Nicotine and metabolite disposition in meconium is poorly characterized, and correlation of analytes' concentrations with neonatal outcomes is unexplored. Our objectives were to quantify nicotine, cotinine, trans-3'-hydroxycotinine (OH-cotinine), nornicotine, norcotinine, and glucuronide concentrations in meconium, identify the best biomarkers of in utero tobacco exposure, compare meconium concentrations of tobacco-exposed and nonexposed neonates, and investigate concentration-outcome relationships.

METHODS

We quantified concentrations of nicotine and 4 metabolites with and without hydrolysis simultaneously in meconium from tobacco-exposed and nonexposed neonates by liquid chromatography-tandem mass spectrometry. We compared meconium concentrations to birth weight, length, head circumference, gestational age, and 1- and 5-min Apgar scores.

RESULTS

Nicotine, cotinine, and OH-cotinine were the most prevalent and abundant meconium tobacco biomarkers and were found in higher concentrations in tobacco-exposed neonates. Whereas cotinine and OH-cotinine are glucuronide bound, performing the lengthy and costly enzymatic hydrolysis identified only 1 additional positive specimen. Unconjugated nicotine, cotinine, or OH-cotinine meconium concentration >10 ng/g most accurately discriminated active from passive and nonexposed neonates. There was no significant correlation between quantitative nicotine and metabolite meconium results and neonatal outcomes, although presence of a nicotine biomarker predicted decreased head circumference.

CONCLUSIONS

Unconjugated nicotine, cotinine, and OH-cotinine should be analyzed in meconium to detect in utero tobacco exposure, as approximately 25% of positive specimens did not contain cotinine. Immunoassay testing monitoring cotinine only would underestimate the prevalence of prenatal tobacco exposure.

[Air pollution and low birth weight in the city of Rio de Janeiro, Brazil, 2002]

The objective of this study was to evaluate the effect of air pollution on low birth weight in full term singleton newborns in the city of Rio de Janeiro, Brazil. The study adopted a cross-sectional design based on the year 2002. Data on live births were obtained from the Live Birth Information System of the Brazilian Ministry of Health. Low birth weight was defined as less than 2,500 g. Maternal exposure to air pollution was defined as the mean for a given pollutant over each trimester of pregnancy and was assessed taking birth date into account. Adjusted odds ratios (OR) were estimated for each potential risk factor. For PM(10), CO, and NO(2), no significant increases were detected. For SO(2), the OR of the fourth interquartile range of exposure in the third trimester of pregnancy was 1.149 (95%CI: 1.016-1.301). For O(3), the estimated OR was 0.830 (95%CI: 0.750-0.987). When exposure variable was regarded as a continuous measure, the OR for PM(10), CO, and SO2 in the third trimester were not statistically significant and were 1.089, 2.223, and 1.259, respectively.

Tabaco, álcool e outras drogas entre adolescentes em Pelotas, Rio Grande do Sul, Brasil: uma perspectiva de gênero

Este estudo teve o objetivo de examinar a relação entre gênero e utilização de substâncias psicoativas entre adolescentes (consumo de bebidas alcoólicas, fumo e uso de drogas ilícitas). Em 2002 foi realizado um estudo transversal na área urbana de Pelotas, extremo-sul do Brasil. Foi empregada amostragem em múltiplos estágios para se obter uma amostra de adolescentes entre 15 e 18 anos de idade. As entrevistas foram realizadas com questionário auto-aplicado. Tabagismo foi mais prevalente entre as meninas, enquanto o consumo de bebida alcoólica no mês anterior às entrevistas foi maior entre os meninos. Por outro lado, a proporção de adolescentes que relataram uso de drogas ilícitas no mês que antecedeu as entrevistas não esteve relacionada ao gênero. O maior consumo de tabaco entre meninas que entre meninos pode indicar risco de expansão do consumo desta substância por mulheres de outras faixas etárias em gerações futuras, o que justifica preocupação e esforços específicos.

In utero exposure to smoking and newborn neurobehavior: how to assess neonatal withdrawal syndrome?

Recent studies postulate neurotoxic effects of prenatal tabacco exposure, passive addiction, and neonatal nicotine withdrawal syndrome in newborns in utero exposed to maternal smoking. The neonatal withdrawal syndrome is characterized by irritability, tremors, and sleep disturbances, most typically observed in newborns of heavy smoking mothers.

[Birth weight and familial smoking]

INTRODUCTION

Tobacco smoking during pregnancy is an important risk factor in the pediatric population and has been associated with an increase in low birth weight (LBW) infants.

PATIENTS AND METHODS

We carried out a retrospective case-control study of infants admitted to the Infants Department of the Hospital Universitario Infantil Niño Jesús in Madrid. Data from 2370 infants admitted to the hospital between 2002 and 2004 were collected.

RESULTS

The odds ratio (OR) for having a LBW infant was 1.42 (95 % CI: 1.017-1.985) among mothers who smoked during pregnancy and was 1.37 (95 % CI: 1.014-1.863) among women whose partners smoked. Gestational age was also a predictive factor of birth weight: the OR was 0.585 (95 % CI: 0.545-0.628). No significant differences for risk of LBW were found between sexes (OR: 1.25; 95 % CI: 0.934-1.671).

CONCLUSIONS

Our results should reinforce the importance of smoking prevention during and after pregnancy in both parents, which could reduce many complications in children's health with a high medical, social and economic cost.