Maternal Pesticide Use and Birth Weight in the Agricultural Health Study

ABSTRACT

Studies examining the association between maternal pesticide exposure and low birth weight yield conflicting results. The authors examined the association between maternal pesticide use and birth weight among women in the Agricultural Health Study, a large study of pesticide applicators and their spouses in Iowa and North Carolina. The authors evaluated self-reported pesticide use of 27 individual pesticides in relation to birth weight among 2246 farm women whose most recent singleton birth occurred within 5 years of enrollment (1993–1997). The authors used linear regression models adjusted for site, preterm birth, medical parity, maternal body mass index, height, and smoking. The results showed that mean infant birth weight was 3586 g (± 546 g), and 3% of the infants were low birth weight (<2500 g). First-trimester pesticide-related tasks were not associated with birth weight. Ever use of the pesticide carbaryl was associated with decreased birth weight (?82 g, 95% confidence interval [CI] = ?132, ?31). This study thus provides limited evidence about pesticide use as a modulator of birth weight. Overall, the authors observed no associations between birth weight and pesticide-related activities during early pregnancy; however, the authors have no data on temporal specificity of individual pesticide exposures prior to or during pregnancy and therefore cannot draw conclusions related to these exposure windows. Given the widespread exposure to pesticide products, additional evaluation of maternal pregnancy exposures at specific time windows and subsequent birth outcomes is warranted.     

新生儿低体重因素调查分析:不等比例匹配病例一对照研究

为了研究影响新生儿低体重的因素,我们于1985年9月至1986年6月在北京市东城区进行了一次病例-对照研究,研究对象包括此区5个地段保健科所辖范围的84名低体重儿及其父母和301名合格对照。使用齒单四格表方法初步筛选重要因素,再以多元Logistic回归估计各重要因素作用大。研究结果表明:父母亲身高;母亲孕期营养状况;早产;父母亲职业接触化学物质;父亲抽烟等是影响新生儿低体重的因素。     

Trimester of Maternal Gestational Weight Gain and Offspring Body Weight at Birth and Age Five

To investigate associations of trimester-specific GWG with fetal birth size and BMI at age 5?years. We examined 3,015 singleton births to women without pregnancy complications from the Child Health and Development Studies prospective cohort with measured weights during pregnancy. We used multivariable regression to examine the associations between total and trimester gestational weight gain (GWG) and birth weight for gestational age and child BMI outcomes, adjusting for maternal age, race/ethnicity, education, marital status, parity, pre-pregnancy body mass index (BMI), and smoking; paternal overweight, gestational age, and infant sex. We explored differences in associations by maternal BMI and infant sex. GWG in all trimesters was significantly and independently associated with birth weight with associations stronger, though not significantly, in the second trimester. First trimester GWG was associated with child BMI outcomes (OR for child overweight?=?1.05; 95% CI?=?1.02, 1.09). Each kg of first trimester GWG was significantly associated with increased child BMI z-score in women of low (???=?0.099; 95% CI?=?0.034, 0.163) and normal (???=?0.028; 95% CI?=?0.012, 0.044), but not high pre-pregnancy BMI. GWG in all trimesters was associated with birth weight; only first trimester GWG was associated with child BMI. If replicated, this information could help specify recommendations for maternal GWG and elucidate mechanisms connecting GWG to child BMI.     

Assessment of Risk Factors for Low Birth Weight Deliveries

Recognition of a higher than average incidence of low birth weight (LBW) deliveries in areas of Eastern Pennsylvania led to an analysis of more than 5,500 deliveries in one of the region's hospital systems to investigate the predictors of LBW in that population. Results of multivariate analysis indicate key variables that contribute to LBW: in particular, racial/ethnic background and specific medical problems during pregnancy, including preeclampsia, incompetent cervix, bleeding, low BMI and lack of adequate weight gain. Results were incorporated into training in best practices for prenatal care in the city's prenatal clinics.     

Maternal Hemoglobin Concentrations and Birth Weight,Low Birth Weight (LBW), and Small for Gestational Age (SGA): Findings from a Prospective Study in Northwest China

Birth weight and related outcomes have profound influences on life cycle health, but the effect of maternal hemoglobin concentration during pregnancy on birth weight is still unclear. This study aims to reveal the associations between maternal hemoglobin concentrations in different trimesters of pregnancy and neonatal birth weight, LBW, and SGA. This was a prospective study based on a cluster-randomized controlled trial conducted from July 2015 to December 2019 in rural areas of Northwest China. Information on maternal socio-demographic status, health-related factors, antenatal visits, and neonatal birth outcomes were collected. A total of 3748 women and their babies were included in the final analysis. A total of 65.1% and 46.3% of the participants had anemia or hemoglobin ≥ 130 g/L during pregnancy. In the third trimester, maternal hemoglobin concentration was associated with birth weight in an inverted U-shaped curve and with the risks of LBW and SGA in extended U-shaped curves. The relatively higher birth weight and lower risks for LBW and SGA were observed when hemoglobin concentration was 100–110 g/L. When maternal hemoglobin was <70 g/L or >130 g/L, the neonatal birth weight was more than 100 g lower than that when the maternal hemoglobin was 100 g/L. In conclusion, both low and high hemoglobin concentrations in the third trimester could be adverse to fetal weight growth and increase the risks of LBW and SGA, respectively. In addition to severe anemia, maternal hemoglobin >130 g/L in the third trimester should be paid great attention to in the practice of maternal and child health care.     

上海市长宁区足月低出生体重儿危险因素的病例-对照研究

[目的]探讨上海市长宁区足月低出生体重儿发生的可能危险因素。[方法]对2006年1月1日至2006年12月31日在上海市长宁区妇幼保健院出生的体重〈2500g，孕周≥37周的单胎足月低出生体重儿和体重≥2500g，孕周≥37周的单胎正常对照组婴儿进行病例-对照研究，在问卷调查的基础上，采用二项式Logistic回归对足月低出生体重儿的影响因素进行分析。[结果]本研究共收集到低出生体重儿88例，正常新生儿113例。低出生体重儿的平均体重为（2285．75±220．00）g，平均身长为（45．33±2．42）cm。正常新生儿的平均体重为（3346．65±421．78）g，平均身长为（48．81±1．45）cm。单因素Logistic回归分析显示，脐带异常、痛经史、既往疾病史、妊娠并发症、饮水情况和孕期感冒均与低出生体重儿的发生相关。经多因素Logistic校正后，发现低出生体重儿发生的影响因素是脐带异常、痛经史和饮用煮沸的河水江水井水（P〈0．05）。[结论]脐带异常、痛经史和饮用煮沸的河水江水井水可能是低出生体重儿的影响因素。     

Maternal Health Risk Assessment and Behavioral Intervention in the NICU Setting Following Very Low Birth Weight Delivery

Objectives To investigate whether maternal health risk assessment and behavioral intervention in the neonatal intensive care unit (NICU) improves women’s health care seeking and health behaviors following the birth of a very low birth weight (VLBW) infant. Methods Using a quasi-experimental non-equivalent control group pretest/posttest design, 80 women who had given birth to a VLBW infant that was admitted to the NICU were enrolled into one of two cohorts: 40 into a ‘Minimal Intervention’ cohort, who received a single session risk assessment and health education pamphlets, and 40 into an ‘Enhanced Intervention’ cohort, who received five counseling sessions targeting identified risks. The proportion of women with specific health care seeking and health behaviors in the two cohorts were compared at baseline and 3- and 9-months post-intervention. Results Women in the Enhanced Intervention cohort were more likely to attend the postpartum visit (73 % vs. 48 %; p = 0.04), ingest folic acid daily (65 % vs. 19 %, p < 0.001), and correctly and consistently use a method of contraception (82 % vs. 63 %, p = 0.03) over the 9-month follow-up period. In multivariate analysis, the between-cohort differences in daily folic acid use (aOR = 3.45, 95 % CI 1.61–7.40) and correct and consistent use of a method of contraception (aOR = 1.46, 95 % CI 1.05–2.06) remained statistically significant at 9-months and the reduction in risk of unintended pregnancy nearly achieved statistical significance (aOR = 0.62, 95 % CI 0.12–1.0). Conclusions for Practice This study provides support for the implementation of maternal risk assessment and behavioral intervention in the NICU setting to promote women’s positive health care seeking and health behaviors.

     

Birth Weight,Maternal Body Mass Index,and Early Childhood Growth: A Prospective Birth Cohort Study in China

Background

The relations of birth weight and maternal body mass index (BMI) to overweight remain unresolved. We prospectively examined the relations of birth weight with various anthropometric measures at age 3 to 6 years, the effect of maternal BMI, and the patterns of these relations in an analysis using 9 birth weight categories.

Methods

The subjects were 210 172 singleton infants born alive with a gestational age ≥28 weeks between October 1993 and December 1996; the subjects were followed up in 2000. Birth weight, maternal height and weight, and other relevant information were measured or collected prospectively. Overweight and underweight were defined by using National Center for Health Statistics/World Health Organization reference data. Logistic regression models were used to estimate relative risks. Analyses stratified by quartile of maternal BMI were performed to examine the effects of maternal BMI on the associations of birth weight with overweight and underweight.

Results

Birth weight was linearly associated with height, weight, and BMI at age 3–6 years. Adjustment for maternal BMI did not alter this association. Birth weight was positively associated with overweight and negatively associated with underweight. The relation curves for both overweight and underweight resembled half of a flat parabolic curve. The associations for overweight and underweight were slightly stronger for the highest and lowest quartiles of maternal BMI, respectively.

Conclusions

Higher birth weight is associated with an increased risk for childhood overweight, and lower birth weight with an increased risk for underweight. The associations between birth weight and early childhood anthropometric growth measures could not explained by maternal BMI.Key words: birth weight, overweight, underweight, maternal body mass index     

Maternal Exposure to Nitrogen Dioxide during Pregnancy and Offspring Birth Weight: Comparison of Two Exposure Models

Background

Studies of the effects of air pollutants on birth weight often assess exposure with networks of permanent air quality monitoring stations (AQMSs), which have a poor spatial resolution.

Objective

We aimed to compare the exposure model based on the nearest AQMS and a temporally adjusted geostatistical (TAG) model with a finer spatial resolution, for use in pregnancy studies.

Methods

The AQMS and TAG exposure models were implemented in two areas surrounding medium-size cities in which 776 pregnant women were followed as part of the EDEN mother–child cohort. The exposure models were compared in terms of estimated nitrogen dioxide (NO₂) levels and of their association with birth weight.

Results

The correlations between the two estimates of exposure during the first trimester of pregnancy were r = 0.67, 0.70, and 0.83 for women living within 5, 2, and 1 km of an AQMS, respectively. Exposure patterns displayed greater spatial than temporal variations. Exposure during the first trimester of pregnancy was most strongly associated with birth weight for women living < 2 km away from an AQMS: a 10-μg/m³ increase in NO₂ exposure was associated with an adjusted difference in birth weight of −37 g [95% confidence interval (CI), −75 to 1 g] for the nearest-AQMS model and of −51 g (95% CI, −128 to 26 g) for the TAG model. The association was less strong (higher p-value) for women living within 5 or 1 km of an AQMS.

Conclusions

The two exposure models tended to give consistent results in terms of association with birth weight, despite the moderate concordance between exposure estimates.     

江门市新会区低出生体重儿影响因素调查与干预对策研究

目的 调查分析影响新会区低出生体重儿发生的危险因素,为制定预防措施提供科学依据.方法 调查2006-2007年新会区低出生体重儿发生的影响因素,用病例对照研究方法,对721名低出生体重儿和对照组进行单因素分析及Logistic多因素回归分析.结果 单因素及多因素Logistic回归分析皆显示:早产、多胎、胎膜早破、妊高征、前置胎盘、产检次数<5次、流动户口、小学及以下文化、被动吸烟和家庭月收入<2 000元是低出生体重儿发生的危险因素.结论 低出生体重的发生受多种因素的影响,早产、妊高征、母亲文化程度低、被动吸烟等因素可显著增加危险性,应采取综合性措施,特别是要加强孕产期保健及高危妊娠的管理,以此降低低出生体重儿发生率.     

Second Births to Teenage Mothers: Risk Factors For Low Birth Weight and Preterm Birth

CONTEXT: Teenagers are more likely than older women to have a low-birth-weight infant or a preterm birth, and the risks may be particularly high when they have a second birth. Identifying predictors of these outcomes in second teenage births is essential for developing preventive strategies.
METHODS: Birth certificate data for 1993–2002 were linked to identify second births to Milwaukee teenagers. Predictors of having a low-birth-weight second infant or a preterm second birth were identified using logistic regression.
RESULTS: The same proportion of first and second infants were low-birth-weight (12%), but second births were more likely than first births to be preterm (15% vs. 12%). In analyses that adjusted for demographic, pregnancy and behavioral characteristics, the odds that a second infant was low-birth-weight or preterm were elevated if the mother smoked during pregnancy (odds ratios, 2.2 and 1.9, respectively), had inadequate prenatal weight gain (1.8 and 1.4), had an interpregnancy interval of less than 18 months (1.6–2.9 and 1.4–2.3) or was black (2.7 and 1.7). Women who had received an adequate level of prenatal care had reduced odds of both outcomes (0.6 and 0.4). Women younger than 16 also had increased odds of having a low-birth-weight second infant. Further adjustment for socioeconomic characteristics yielded largely the same results. In addition, women who were unmarried or did not identify a father were at increased risk of both outcomes (1.5 for each), and poor women were at risk of having a low-birth-weight infant (1.3).
CONCLUSIONS: Predictors of poor birth outcomes include modifiable behaviors. Prenatal interventions addressing these behaviors could help improve outcomes.     

上海市闵行区低出生体重儿危险因素研究

目的探讨影响上海市闵行区低出生体重儿(LBW)的可能危险因素,为进一步制定低出生体重相关干预政策与对策提供参考依据。方法采用病例对照研究的方法,通过上门访谈的方式进行流行病学问卷调查,使用SPSS18.0建立数据库并完成分析。结果通过单因素Logistic回归分析,发现本次怀孕胎数、母亲被动吸烟、蔬菜摄入频率、水果摄入频率、先兆早产、父亲被动吸烟、环境污染和饲养宠物8个因素与LBW的发生有联系(P<0.05)。将筛选出的8个危险因素作二分类变量Logistic回归分析,最终进入模型的变量为本次怀孕胎数、先兆早产和环境污染3个因素。结论 LBW的发生与孕妇的怀孕情况、行为习惯以及生活环境等多方面因素有关系,应采取针对性的措施有效降低LBW的发生。     

Association of Maternal Dietary Patterns during Pregnancy and Offspring Weight Status across Infancy: Results from a Prospective Birth Cohort in China

Literature on maternal dietary patterns during pregnancy and offspring weight status have been largely equivocal. We aimed to investigate the association of maternal dietary patterns with infant weight status among 937 mother–infant dyads in a Chinese birth cohort. We assessed maternal diet during pregnancy using food frequency questionnaires (FFQ) and three-day food diaries (TFD) and examined infants’ body weight and length at birth, 1, 3, 6, 8 and 12 months. Maternal adherence to the “protein-rich pattern (FFQ)” was associated with lower infant body mass index z-scores (BMIZ) at birth, 3 and 6 months and lower odds of overweight and obesity (OwOb) across infancy (quartile 3 (Q3) vs. quartile 1 (Q1): odds ratio (OR): 0.50, (95% confidence interval: 0.27, 0.93)). Maternal adherence to the “vegetable–fruit–rice pattern (FFQ)” was associated with higher BMIZ at birth, 3 and 6 months and higher odds of OwOb across infancy (Q3 vs. Q1: OR: 1.79, (1.03, 3.12)). Maternal adherence to the “fried food–bean–dairy pattern (TFD)” was associated with lower BMIZ at 3, 6, 8 and 12 months and lower odds of OwOb (Q3 vs. Q1: OR: 0.54, (0.31, 0.95)). The study results may help to develop interventions and to better define target populations for childhood obesity prevention.     

Factors Affecting Latina Immigrants’ Perceptions of Maternal Health Care: Findings From a Qualitative Study

Due to the influx of Latino immigration in the United States, health care services are faced with the challenge of meeting the needs of this growing population. In this qualitative study, we explored Latina immigrants’ experiences with maternal health care services. We found that despite enduring language barriers and problems, Spanish-speaking women expressed satisfaction with their care. Factors influencing women's perceptions of care included sociocultural norms (respeto, personalismo, and familismo), previous experiences with care in their countries of origin, having healthy babies, and knowledge about entitlement to interpreter services. We offer recommendations for public health practice and research.     

Industrial Noise Exposure and Risk Factors for Cardiovascular Disease: Findings from the CORDIS Study

Previous studies of the association between occupational noise exposure and cardiovascular disease (CVD) or risk factors for CVD are primarily either cross-sectional or retrospective, whereas the design of the CORDIS study was both cross-sectional and longitudinal. It had three phases: Phase I was conducted during 1985-87 among 6,016 employees from 21 factories. Recorded were medical, ergonomic, environmental (including noise levels at the various work stations) and psychological data. Phase II was conducted during 1988-90, at 18 of the 21 original factories and included similar data collected from 3,509 subjects. Phase III was conducted during the years 1995-96 and 4,995 workers who participated in Phases I and II completed questionnaires pertaining to medical, occupational and life style variables. Mortality and cancer morbidity data were obtained over an 8 year follow-up period for all subjects. Results from Phase I, revealed no association between noise exposure and resting blood pressure. Positive association was found for serum lipids in women and in young men. Noise annoyance had an additive effect on this outcome. In addition, recurrent daily noise exposure was found to be associated with elevated acute resting heart rate. Results of Phase II showed that chronic exposure to high noise levels during the 2-4 years of the follow-up resulted in changes of 3.9 mmHg in SBP and 3.3 mmHg in DBP, among workers performing complex jobs. In workers performing simple jobs these changes were 0.3 and 0.4 mmHg. Thus the type of work performed appears to be a significant factor. Results of Phase III revealed that there was a trend for positive association between past noise exposure measured at Phase I and 8 years incidence of cardiovascular morbidity, mortality and total mortality. This trend was statistically significant for total mortality (hazard ratio = 1.97, 95% CI 1.28-4.54) even after controlling for possible confounders. In summary, tests for association between noise exposure and cardiovascular risk factors, or cardiovascular morbidity and mortality, and total mortality have yielded mixed results. Reasons for this are discussed, as well as suggestions for further research.     

Maternal Dietary Patterns during Pregnancy in Relation to Offspring Forearm Fractures: Prospective Study from the Danish National Birth Cohort

Limited evidence exists for an association between maternal diet during pregnancy and offspring bone health. In a prospective study, we examined the association between dietary patterns in mid-pregnancy and offspring forearm fractures. In total, 101,042 pregnancies were recruited to the Danish National Birth Cohort (DNBC) during 1996–2002. Maternal diet was collected by a food frequency questionnaire. Associations were analyzed between seven dietary patterns extracted by principal component analysis and offspring first occurrence of any forearm fracture diagnosis, extracted from the Danish National Patient Register, between time of birth and end of follow-up (<16 year) (n = 53,922). In multivariable Cox regression models, offspring of mothers in the fourth vs. first quintile of the Western pattern had a significant increased risk (Hazard ratio, 95% confidence interval: 1.11, 1.01–1.23) of fractures, and there was a borderline significant positive trend (p = 0.06). The other dietary patterns showed no associations and neither did supplementary analyses of macro- and micronutrients or single food groups, except for the intake of artificially sweetened soft drinks, which was positively associated with offspring forearm fractures (p = 0.02). In the large prospective DNBC high mid-pregnancy consumption of Western diet and artificially sweetened soft drinks, respectively, indicated positive associations with offspring forearm fractures, which provides interesting hypotheses for future research.     

197例低出生体重儿的影响因素分析

目的通过分析新会区低出生体重儿的影响因素,初步探讨降低低出生体重儿发生率的相关措施。方法采用横断面抽样调查方法,抽查本院2003年1月—2003年12月产科和新生儿科住院病历,进行低出生体重儿与非低出生体重儿的对照研究。结果(1)197例低出生体重儿中早产119例,占低出生体重儿的比例为60.4%;多胎、外地户口、产检次数<5次、母亲胎膜早破、前置胎盘、妊高征所占比例分别为18.3%,12.7%、27.9%、35.5%,9.1%和14.7%。(2)统计学分析结果:低出生体重儿与非低出生体重儿比较,早产、多胎、外地户口、产检次数<5次、胎膜早破、前置胎盘、妊高征等影响因素差异有显著性(P<0.05)。结论低出生体重儿的发生受多种因素的影响,应采取综合预防措施以降低低出生体重儿的发生率。