Maternal asthma and risk of preterm delivery

PURPOSE: We studied the relation between maternal history of asthma and preterm delivery. METHODS: The 312 preterm delivery cases, studied in aggregate, and in subgroups (spontaneous preterm labor, preterm premature rupture of membranes, medically induced preterm delivery), were compared with 424 randomly selected women who delivered at term. Maternal medical records provided information on maternal lifetime asthma status, pregnancy outcome, and sociodemographic characteristics. Using multivariate logistic regression, we derived maximum likelihood estimates of adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Maternal history of asthma was associated with an increased risk of preterm delivery overall (OR = 2.37; 95% CI 1.15-4.88). Analyses of preterm delivery sub-groups indicated that maternal history of asthma was associated with at least a doubling in risk of spontaneous preterm labor (OR = 2.35; 95% CI 0.84-6.58) and medically induced preterm delivery (OR = 2.69; 95% CI 1.11-6.53), though only the latter approached statistical significance. There was some evidence of a modest association between maternal asthma and risk of preterm premature rupture of membranes (OR = 1.63; 95% CI 0.50-5.33). CONCLUSIONS: These results support the hypothesis that maternal asthma is associated with an increased risk of preterm labor and delivery.     

Maternal second-trimester serum ferritin concentrations and subsequent risk of preterm delivery

We studied the relationship between maternal second-trimester serum ferritin concentrations and preterm delivery. The 312 preterm delivery cases, studied in aggregate and in subgroups [spontaneous preterm labour, preterm premature rupture of membranes, medically induced preterm delivery, moderate preterm delivery (gestational age at delivery 34-36 weeks) and very preterm delivery (gestational age at delivery <34 weeks)] were compared with 424 randomly selected women who delivered at term. Maternal ferritin concentrations, measured in serum collected at 17 weeks gestation on average, was determined using a two-site chemiluminometric immunoassay. Using multiple logistic regression, we derived maximum likelihood estimates of adjusted odds ratios (OR) and 95% confidence intervals [CI]. Elevation in maternal second-trimester ferritin was weakly associated with the risk of preterm delivery overall. After adjusting for possible confounding by maternal age, race/ethnicity, parity, Medicaid payment status and smoking during the index pregnancy, the OR for extreme quartiles (>64.5 vs. <26.0 ng/mL) of ferritin was 1.3 [95% CI 0.8, 2.1]. Stratified analyses indicated that elevated maternal serum ferritin was associated with an increased risk of preterm premature rupture of membranes (OR = 2.1; 95% CI 1.1, 4.1), but not with spontaneous preterm labour (OR = 0.9; 95% CI 0.4, 1.7) or medically induced preterm delivery (OR = 1.1; 95% CI 0.6, 2.0). The relationship between elevated maternal second-trimester serum ferritin concentrations and preterm delivery was strongest for spontaneous very preterm deliveries (<34 weeks gestation). Women with ferritin concentrations in the highest decile (>96 ng/mL) experienced a 2.7-fold increased risk of delivering before 34 completed weeks, compared with women with concentrations <26.0 ng/mL. These results are consistent with some previous reports, and further underline the potential for heterogeneity in the aetiology of preterm delivery.     

Chemical hair treatments and adverse pregnancy outcome among Black women in central North Carolina

Several studies suggest that toxic chemicals in hair products may be absorbed through the scalp in sufficient amounts to increase the risks of adverse health effects in women or their infants. This case-control study of 525 Black women from three counties in North Carolina who had delivered a singleton, liveborn infant examined whether exposure to chemicals used in hair straightening and curling increased the odds that the infant was preterm or low birth weight. Cases consisted of 188 preterm and 156 low birth weight births (for 123 women, their infant was both low birth weight and preterm). Controls were 304 women who delivered term and normal birth weight infants. Women who used a chemical hair straightener at any time during pregnancy or within 3 months prior to conception had an adjusted odds ratios (OR) of 0.7 (95% confidence interval (CI) 0.4-1.1) for preterm birth and 0.6 (95% CI 0.4-1.1) for low birth weight. Exposure to chemical curl products was also not associated with preterm delivery (adjusted OR = 0.9, 95% CI 0.5-1.8) or low birth weight (adjusted OR = 1.0, 95% CI 0.5-1.9). Despite this failure to find an association, continued search for risk factors to which Black women are uniquely exposed is warranted.     

孕期被动吸烟对妊娠并发症及妊娠结局的影响

目的了解孕期被动吸烟发生情况,并探讨其对妊娠并发症及结局的影响。方法选取2012年4月―2013年3月在我国15家医疗保健机构分娩的8926例单胎活产产妇作为研究对象,使用自制调查问卷收集孕期被动吸烟发生情况、妊娠并发症和结局等信息,采用单因素和多因素Logistic回归分析模型分析孕期被动吸烟对妊娠并发症及结局的影响。结果共1801例产妇在孕期经历被动吸烟。控制混杂因素后,孕期经历被动吸烟的产妇妊娠期糖尿病(gestational diabetes mellitus,GDM)的发生风险是非被动吸烟者的1.359倍(95%CI:1.146~1.612,P<0.001),胎膜早破的风险为1.290倍(95%CI:1.095~1.520,P=0.002),早产的风险为1.367倍(95%CI:1.155~1.619,P<0.001),娩出低出生体重儿的风险为1.341倍(95%CI:1.079~1.668,P=0.008)。与非被动吸烟者相比,平均每周被动吸烟天数≥4天者胎膜早破、早产和低出生体重儿的发生风险分别为非被动吸烟者的1.402倍(95%CI:1.104~1.780,P=0.006)、1.690倍(95%CI:1.339~2.132,P<0.001)和1.584倍(95%CI:1.172~2.141,P=0.023)。结论被调查产妇孕期被动吸烟率较高,孕期经历被动吸烟能够增加妊娠期糖尿病、胎膜早破、早产和低出生体重儿的发生风险。     

Maternal coffee drinking in pregnancy and risk of small for gestational age birth

OBJECTIVE: We have analysed the association between coffee drinking before and during the three trimesters of pregnancy and risk of small for gestational age (SGA) birth. METHODS: Cases were 555 women who delivered SGA births (ie <10th percentile according Italian standard). The controls included 1966 women who gave birth at term (>/=37 weeks of gestation) to healthy infants of normal weight. RESULTS: In comparison with nondrinkers, the ORs for SGA birth were 1.3 (95% confidence interval, CI, 0.9-1.9) for consumption of four or more cups of coffee/day before pregnancy, and 1.2 (95% CI 0.8-1.8), 1.2 (95% CI 0.8-1.8) and 0.9 (95% CI 0.6-1.4) for consumption of three or more cups of coffee/day during the first, second and third trimester of pregnancy, respectively. CONCLUSION: These findings were consistent in women who delivered preterm and at term births and were not affected by potential confounding such as smoking.     

早产影响因素的前瞻性队列研究

目的 分析中国早产的流行现状及危险因素,为早产的预防提供参考依据.方法 本研究数据来源于中国孕产妇队列研究.协和项目(Chinese Pregnant Women Cohort Study,CP-WCS),通过问卷调查和医院信息系统(hospital information system,HIS)收集孕妇基本情况和分娩...     

孕期体力活动、久坐行为与胎膜早破发生风险的相关性及剂量反应关系

目的 探究孕期妇女体力活动(physical activity,PA)、久坐行为与胎膜早破(prema-ture rupture of membranes,PROM)发生风险的相关性及剂量反应关系.方法 采用国际体力活动短问卷收集中国孕产妇队列研究?协和项目中孕妇的体力活动状况和静坐时间(sedentary time,...     

Coffee intake and incidence of hypertension

BACKGROUND: The long-term longitudinal evidence for a relation between coffee intake and hypertension is relatively scarce. OBJECTIVE: The objective was to assess whether coffee intake is associated with the incidence of hypertension. DESIGN: This study was conducted on a cohort of 2985 men and 3383 women who had a baseline visit and follow-up visits after 6 and 11 y. Baseline coffee intake was ascertained with questionnaires and categorized into 0, >0-3, >3-6, and >6 cups/d. Hypertension was defined as a mean systolic blood pressure (SBP) >or=140 mm Hg over both follow-up measurements, a mean diastolic blood pressure (DBP) >or=90 mm Hg over both follow-up measurements, or the use of antihypertensive medication at any follow-up measurement. RESULTS: Coffee abstainers at baseline had a lower risk of hypertension than did those with a coffee intake of >0-3 cups/d [odds ratio (OR): 0.54; 95% CI: 0.31, 0.92]. Women who drank >6 cups/d had a lower risk than did women who drank >0-3 cups/d (OR: 0.67; 95% CI: 0.46, 0.98). Subjects aged >or=39 y at baseline had 0.35 mm Hg (95% CI: -0.59, -0.11 mm Hg) lower SBP per cup intake/d and 0.11 mm Hg lower DBP (95% CI: -0.26, 0.03 mm Hg) than did those aged <39 y at baseline, although the difference in DBP was not statistically significant. CONCLUSIONS: Coffee abstinence is associated with a lower hypertension risk than is low coffee consumption. An inverse U-shaped relation between coffee intake and risk of hypertension was observed in the women.     

Caffeinated coffee, decaffeinated coffee and endometrial cancer risk: a prospective cohort study among US postmenopausal women

There is plausible biological evidence as well as epidemiologic evidence to suggest coffee consumption may lower endometrial cancer risk. We evaluated the associations between self-reported total coffee, caffeinated coffee and decaffeinated coffee, and endometrial cancer risk using the Women's Health Initiative Observational Study Research Materials obtained from the National Heart, Lung, and Blood Institute Biological Specimen and Data Repository Coordinating Center. Our primary analyses included 45,696 women and 427 incident endometrial cancer cases, diagnosed over a total of 342,927 person-years of follow-up. We used Cox-proportional hazard models to evaluate coffee consumption and endometrial cancer risk. Overall, we did not find an association between coffee consumption and endometrial cancer risk. Compared to non-daily drinkers (none or <1 cup/day), the multivariable adjusted hazard ratios for women who drank ≥4 cups/day were 0.86 (95% confidence interval (CI) 0.63, 1.18) for total coffee, 0.89 (95% CI 0.63, 1.27) for caffeinated coffee, and 0.51 (95% CI 0.25, 1.03) for decaf coffee. In subgroup analyses by body mass index (BMI) there were no associations among normal-weight and overweight women for total coffee and caffeinated coffee. However among obese women, compared to the referent group (none or <1 cup/day), the hazard ratios for women who drank ≥2 cups/day were: 0.72 (95% CI 0.50, 1.04) for total coffee and 0.66 (95% CI 0.45, 0.97) for caffeinated coffee. Hazard ratios for women who drank ≥2 cups/day for decaffeinated coffee drinkers were 0.67 (0.43-1.06), 0.93 (0.55-1.58) and 0.80 (0.49-1.30) for normal, overweight and obese women, respectively. Our study suggests that caffeinated coffee consumption may be associated with lower endometrial cancer risk among obese postmenopausal women, but the association with decaffeinated coffee remains unclear.     

Some life-style factors and the risk of invasive epithelial ovarian cancer in Swedish women

The objective of this nationwide case-control study was to examine body mass index (BMI), alcohol use, coffee consumption, cigarette smoking, and leisure-time physical activity in relation to epithelial ovarian cancer (EOC) risk. Subjects were 655 newly diagnosed EOC cases and 3899 population controls, all 50-74 years of age at recruitment between 1993 and 1995. Data were collected through mailed questionnaires. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression. Women with a BMI 30 kg/m² compared with those with a BMI < 22 kg/m² appeared to have an elevated EOC risk (OR = 1.37, 95% CI: 1.01-1.85), particularly of mucinous (OR = 2.76, 95% CI: 1.15-6.61) and clear-cell histologies (OR = 2.68, 95% CI: 0.96-7.48). The OR for EOC among coffee users reporting 6 daily cups compared with non-users was 0.68 (95% CI: 0.42-1.10). Alcohol consumption was unrelated to EOC risk. Compared to non-smokers the ORs of EOC among current smokers were 0.70 (95% CI: 0.52-0.94) for those who smoked 1-10 cigarettes/day and 0.74 (95% CI: 0.53-1.02) for heavier smokers, while former smokers were at an unaltered risk (OR = 0.83, 95% CI: 0.66-1.04). Reduced EOC risks were observed among women in the highest compared with the lowest physical activity levels both at age 18-30 years (OR = 0.67, 95% CI: 0.52-0.87) and during the last years preceding study enrollment (OR = 0.68, 95% CI: 0.53-0.87). We conclude that women may avoid an excess risk of EOC through maintaining a normal BMI and reduce their risk by participation in leisure-time physical activity. The use of coffee, alcohol, or cigarette smoking does not appearto increase the risk of EOC.     

Influence of maternal smoking on placental abruption in successive pregnancies: a population-based prospective cohort study in Sweden

The authors examined associations between cumulative smoking during a woman's first and second pregnancies and risk of placental abruption in the second pregnancy. They performed a population-based prospective cohort study of 526,690 women who delivered their first two consecutive singletons in Sweden in 1983-2001. Using logistic regression models, the authors found that, among women without placental abruption in the first pregnancy, smoking was associated with increased risk of abruption in the second pregnancy; however, this effect was confined to exposure occurring during the second pregnancy (adjusted odds ratio (OR)=1.8, 95% confidence interval (CI): 1.4, 2.3) but not the first (adjusted OR=1.1, 95% CI: 0.9, 1.3). Among women with a prior abruption, the risk of repeating abruption was increased irrespective of smoking habits. When women smoked during both pregnancies, there was an almost 11-fold increase in risk (adjusted OR=10.9, 95% CI: 7.3, 16.3). These findings suggest that women who quit smoking before pregnancy may benefit from reduced risk of abruption. The observation that the recurrence of abruption is substantially increased regardless of changes in smoking habits suggests that factors other than smoking may influence the recurrence of placental abruption.     

Parkinson's disease risks associated with cigarette smoking, alcohol consumption, and caffeine intake

A reduced risk for Parkinson's disease (PD) among cigarette smokers has been observed consistently during the past 30 years. Recent evidence suggests that caffeine may also be protective. Findings are presented regarding associations of PD with smoking, caffeine intake, and alcohol consumption from a case-control study conducted in western Washington State in 1992-2000. Incident PD cases (n = 210) and controls (n = 347), frequency matched on gender and age were identified from enrollees of the Group Health Cooperative health maintenance organization. Exposure data were obtained by in-person questionnaires. Ever having smoked cigarettes was associated with a reduced risk of PD (odds ratio (OR) = 0.5, 95% confidence interval (CI): 0.4, 0.8). A stronger relation was found among current smokers (OR = 0.3, 95% CI: 0.1, 0.7) than among ex-smokers (OR = 0.6, 95% CI: 0.4, 0.9), and there was an inverse gradient with pack-years smoked (trend p < 0.001). No associations were detected for coffee consumption or total caffeine intake or for alcohol consumption. However, reduced risks were observed for consumption of 2 cups/day or more of tea (OR = 0.4, 95% CI: 0.2, 0.9) and two or more cola drinks/day (OR = 0.6, 95% CI: 0.3, 1.4). The associations for tea and cola drinks were not confounded by smoking or coffee consumption.     

Frequency of eating during pregnancy and its effect on preterm delivery

Frequency of eating or meal patterns during pregnancy may be a component of maternal nutrition relevant to pregnancy outcome. To identify meal patterns of pregnant women and investigate the relation between these meal patterns and preterm delivery, the authors performed an analysis using data from the Pregnancy, Infection, and Nutrition Study (n = 2,065). Women recruited from August 1995 to December 1998 were categorized by meal patterns on the basis of their reported number of meals (breakfast, lunch, and dinner) and snacks consumed per day during the second trimester. An optimal pattern was defined according to the Institute of Medicine recommendation of three meals and two or more snacks per day. In this population, 72 percent of the women met this recommendation, and 235 delivered preterm. Women who consumed meals/snacks less frequently were slightly heavier prior to pregnancy, were older, and had a lower total energy intake. In addition, these women had a higher risk of delivering preterm (adjusted odds ratio = 1.30, 95 percent confidence interval: 0.96, 1.76). There was no meaningful difference in the risk by early versus late preterm delivery, but those who delivered after premature rupture of the membranes (adjusted odds ratio = 1.87, 95 percent confidence interval: 1.02, 3.43) had a higher risk than those who delivered after preterm labor (adjusted odds ratio = 1.11, 95 percent confidence interval: 0.64, 1.89). This study supports previous animal model work of an association between decreased frequency of eating and preterm delivery.     

History of fetal loss and other adverse pregnancy outcomes in relation to subsequent risk of preterm delivery

Objective: To evaluate the association between maternal reproductive history and preterm delivery. Methods: The 312 preterm delivery cases, studied in aggregate, and in subgroups (spontaneous preterm labor, preterm premature rupture of membranes, medically induced preterm delivery, moderate preterm delivery [gestational age at delivery 34–36 weeks], and very preterm delivery [gestational age at delivery <34 weeks]), were compared with 424 randomly selected women who delivered at term. Maternal medical records provided information on maternal reproductive history, pregnancy outcome, as well as sociodemographic characteristics. Using multivariate logistic regression, we derived maximum likelihood estimates of adjusted odds ratios (OR) and 95% confidence intervals (CI). Results: A history of 2+ miscarriages was ( OR = 2.2; 95% CI 1.2–3.9), but a history of 2+ prior induced abortions (OR = 1.2; 95% CI 0.7–2.0) was not, associated with preterm delivery in the index pregnancy. Analyses of preterm delivery subgroups indicated that a history of 2+ miscarriages was associated with an increasedrisk of spontaneous preterm labor (OR = 2.6; 95% CI 1.2–2.8), preterm premature rupture of membrane (OR = 1.8; 95% 0.7–4.4), and medically induced preterm delivery (OR = 1.9; 95% CI 0.8–4.2), though only the former approached statistical significance. Excess risk of preterm delivery was associated with maternal prior history of delivering a stillborn infant (OR = 10.7), a prior history of delivering a newborn that later died during the neonatal period (OR = 3.2), and a prior history of having a pregnancy complicated by spontaneous preterm delivery (OR = 6.0). Generally these associations were evident for each subgroup of preterm delivery, though inferences were often hindered by our relatively small sample size. Conclusions: These results support the hypothesis that maternal adverse reproductive history is associated with an increased risk of preterm labor and delivery.     

Are coffee and tea consumption associated with urinary tract cancer risk? A systematic review and meta-analysis

BACKGROUND: Narrative reviews have concluded that there is a small association between coffee consumption and an increased risk of urinary tract cancer, possibly due to confounding by smoking. No association for tea consumption has been indicated. This systematic review attempts to summarize and quantify these associations both unadjusted and adjusted for age, smoking and sex. METHOD: Thirty-four case-control and three follow-up studies were included in this systematic review. Summary odds ratios (OR) were calculated by meta-regression analyses. RESULTS: The unadjusted summary OR indicated a small increased risk of urinary tract cancer for current coffee consumers versus non-drinkers. The adjusted summary OR were: 1.26 (95% CI : 1.09-1.46) for studies with only men, 1.08 (95% CI : 0.79-1.46) for studies with only women and 1.18 (95% CI : 1.01-1.38) for studies with men and women combined. Neither unadjusted nor adjusted summary OR provided evidence for a positive association between tea consumption and urinary tract cancer. Even though studies differed in methodology, the results were rather consistent. We did not perform dose-response analyses for coffee and tea consumption due to sparse data. CONCLUSIONS: In accordance with earlier reviews, we found that coffee consumption increases the risk of urinary tract cancer by approximately 20%. The consumption of tea seems not to be related to an increased risk of urinary tract cancer.     

Association of maternal caffeine consumption with decrements in fetal growth

Whether caffeine consumption during pregnancy represents a fetal hazard remains uncertain. The authors report on a large prospective study designed to examine this question. In 1996-2000, 2,291 mothers with singleton livebirths in Connecticut and Massachusetts were evaluated after their first prenatal visit and were questioned about caffeine consumption and important confounding factors. Urine samples were provided to analyze urinary caffeine, cotinine, and creatinine levels. Mothers were followed throughout pregnancy to monitor changes in consumption. Pregnancy outcomes were obtained from medical records. Self-reports of caffeine consumption in the first and third trimesters were not associated with intrauterine growth retardation, low birth weight, or preterm delivery. For every 1 mg/g creatinine increase in urinary caffeine, risk of intrauterine growth retardation was essentially unchanged (odds ratio (OR) = 0.96, 95% confidence interval (CI): 0.85, 1.08). In contrast, a 0.005 mg/g creatinine increase in urinary cotinine significantly increased risk (OR = 1.003, 95% CI: 1.001, 1.005). Mean birth weight was reduced by reported caffeine consumption (-28 g per 100 mg of caffeine consumed daily, 95% CI: -0.10, -0.46, p = 0.001) but not mean gestational age. Decaffeinated coffee did not increase risk for any perinatal outcome. This small decrease in birth weight, observed for maternal caffeine consumption, is unlikely to be clinically important except for women consuming >/=600 mg of caffeine daily (approximately six 10-ounce (1 ounce = 28.3 g) cups of coffee).     

Low birthweight at term and the timing of fetal exposure to maternal smoking.

OBJECTIVES. This study was undertaken to evaluate the risk of small-for-gestational-age birth for women who stop smoking or begin to smoke during pregnancy. METHODS. Women with term singleton pregnancies from a hospital-based cohort of 11,177 were classified as (1) nonsmokers; (2) smoked throughout pregnancy; (3) smoked during first trimester only; (4) smoked during first and second trimesters only; and (5) smoked during second and third trimesters or during third trimester only. Risk of small-for-gestational-age birth according to smoking category was estimated and adjusted for confounding factors by logistic regression. RESULTS. Women who stopped smoking by the third trimester were not at increased risk of small-for-gestational-age birth compared with nonsmokers. Women who began smoking during the second or third trimester had an elevated risk of small-for-gestational-age birth (odds ratio [OR] = 1.83; 95% confidence interval [CI] = 1.25, 2.67) similar to that for women who smoked throughout pregnancy (OR = 2.20; 95% CI = 1.90, 2.54). Risk of small-for-gestational-age birth increased with the number of cigarettes smoked during the third trimester. CONCLUSIONS. It is during the third trimester that smoking retards fetal growth, presenting a compelling opportunity for smoking cessation interventions. Programs must emphasize the importance of not resuming smoking late in pregnancy.     

Influence of smoking and snuff cessation on risk of preterm birth

The mechanisms by which antenatal smoking exposure increases the risk of preterm birth remain unknown. Swedish oral moist snuff contains quantities of nicotine comparable to those typically absorbed from cigarette smoking, but does not result in exposure to the products of combustion, for example carbon monoxide. In a nation-wide study of 776,836 live singleton births in Sweden from 1999 to 2009, the authors used multiple logistic regression models to examine associations between cessation of smoking and Swedish snuff use early in pregnancy and risk of preterm birth (before 37 weeks). Compared with non-tobacco users both before and in early pregnancy, the adjusted odds ratios (OR), 95% confidence interval (CI) were OR=0.92, 95% CI 0.84-1.01, for women who stopped using snuff, and OR=0.90, 95% CI 0.87-0.94, for women who stopped smoking. In contrast, continued snuff use and smoking were associated with increased risks of preterm birth (adjusted OR=1.29, 95% CI 1.17-1.43, adjusted OR=1.30, 95% CI 1.25-1.36, respectively). The snuff and smoking-related risks were, if anything, higher for very (before 32 weeks) than moderately (32-36 weeks) preterm birth, and also higher for spontaneous than induced preterm birth. These findings suggest that antenatal exposure to nicotine is involved in the mechanism by which tobacco use increase the risk of preterm birth.     

Associations between black tea and coffee consumption and risk of lung cancer among current and former smokers

Although cigarette smoking is a clear risk factor for lung cancer, the other determinants of lung cancer risk among smokers are less clear. Tea and coffee contain catechins and flavonoids, which have been shown to exhibit anticarcinogenic properties. Conversely, caffeine may elevate cancer risk through a variety of mechanisms. The current study investigated the effects of regular consumption of black tea and coffee on lung cancer risk among 993 current and former smokers with primary incident lung cancer and 986 age-, sex-, and smoking-matched hospital controls with non-neoplastic conditions. Results indicated that lung cancer risk was not different for those with the highest black tea consumption (>or=2 cups/day) compared with nondrinkers of tea [adjusted odds ratio (aOR)=0.90; 95% confidence interval (CI)=0.66-1.24]. However, elevated lung cancer risk was observed for participants who consumed 2-3 cups of regular coffee daily (aOR=1.34; 95% CI=0.99-1.82) or >or=4 cups of regular coffee daily (aOR=1.51, 95% CI=1.11-2.05). In contrast, decaffeinated coffee drinking was associated with decreased lung cancer risk for both participants who consumed or=2 cups/day (aOR=0.64; 95% CI=0.51-0.80). These results suggest that any chemoprotective effects of phytochemicals in coffee and tea may be overshadowed by the elevated risk associated with caffeine in these beverages.     

Maternal Exposures to Cigarette Smoke,Alcohol, and Street Drugs and Neural Tube Defect Occurrence in Offspring

Objectives Cigarettes, alcoholic beverages, and street drugs contain substances potentially toxic to the developing embryo. We investigated whether maternal cigarette smoking, secondhand smoke exposure, and alcohol or street drug use contributed to neural tube defect (NTD) occurrence in offspring. Methods We conducted a population-based case-control study among Mexican American women who were residents of the 14 Texas counties bordering Mexico. Case women had an NTD-affected pregnancy and delivered during 1995–2000. Control women were those who delivered live born infants in the same study area, without an apparent congenital malformation, randomly selected by year and facility. We interviewed women in person, 1–3 months postpartum, to solicit relevant information. Results Nonsmoking mothers exposed to secondhand smoke during the first trimester had an NTD odds ratio (OR) of 2.6 (95% confidence interval (CI) = 1.6, 4.0) compared to those who neither smoked nor were exposed to secondhand smoke. Compared to the referent, the OR among women who smoked less than half a pack a day during the first trimester was 2.2 (95% CI = 1.0, 4.8) and 3.4 (95% CI = 1.2, 10.0) among those who smoked a half pack or more. Adjustment for maternal age, education, body mass index, and folate intake had a negligible effect on results. Alcohol and street drug use had no relation to NTD risk when adjusted for cigarette smoking. Conclusions This study suggests that cigarette smoke including secondhand exposure is not only hazardous to the mother but may also interfere with neural tube closure in the developing embryo.