妊娠期压力对母儿身心健康影响的研究进展

孕妇普遍存在妊娠期压力,但由于压力测量方法和界定压力水平的标准不一,各地妊娠期压力发生率尚不统一.高水平的妊娠期压力在体内下丘脑-垂体-肾上腺皮质系统和交感-肾上腺髓质系统等神经内分泌系统的调节下,不仅可导致早产、低出生体重、妊娠并发症等不良身体健康结局,还会出现孕妇产前焦虑、产后抑郁和子代神经行为发育障碍等影响心理健康的结局.该文就孕妇的妊娠期压力流行现状及其对母儿身心健康影响的研究进展进行综述.     

A Secondary Analysis of Race/Ethnicity and other Maternal Factors Affecting Adverse Birth Outcomes in San Bernardino County

Objectives Though it is the largest county in the lower United States, minimal attention has been given to the elevated rates of poor perinatal outcomes and infant mortality in San Bernardino County. This study sought to analyze adverse birth outcomes such as low birth weight, and infant mortality as an outcome of specific proxy maternal sociodemographic factors. Methods Data from the California Department of Health Services Office of Vital Statistics birth cohort of mothers delivering between 1999 and 2001 (N = 1,590,876 participants) were analyzed. Of those, 5.5% (n = 86,736) were births in San Bernardino County. Low birth weight, very low birth weight, death in infants less than one year of age, and other maternal sociodemographic factors were explored. All events of low birth weight and deaths among infants less than one year of age were used as significant variables in statistical models. Results Black mothers experienced more than twice the rate of very low birth weight (3.89) than their White counterparts (1.39). The most significant contributors to adverse birth outcomes among Black women were length of gestation and maternal education, whereas the most significant predictor of infant mortality was birth weight. Conclusions This study demonstrates that traditional risk factors such as length of gestation and maternal age only partially explain adverse birth outcomes. These findings highlight the need to advocate for the systematic collection of data on maternal education and length gestation and for the promotion of public health initiatives that address these inequities in our most vulnerable of populations.     

The effect of antismoking intervention during pregnancy: an assessment of interactions with maternal characteristics

In a previous experimental study, which included 935 pregnant smokers recruited from private obstetric practices located in a large metropolitan area and from one hospital obstetric clinic, a 92-g difference was found between infants born to women who had antismoking intervention and those born to women in a control group. The current report further examines the effect of intervention on both smoking cessation during pregnancy and birth weight. Specific attention is given to interactions between intervention and maternal characteristics. These maternal characteristics were determined at the time of first prenatal care. A stepwise regression analysis was performed to assess 1) the association of each maternal variable with smoking cessation and birth weight; 2) the effect of intervention on these outcomes after adjusting for the maternal variable; and 3) the interaction effect between intervention and the maternal variable. The effect of intervention on smoking cessation was found to be significantly greater for women who experienced problems early in pregnancy, such as high blood pressure and urinary tract infection. The beneficial effect of intervention on birth weight decreased with age and number of previous low birth weight infants but increased with previous fetal loss. There is some evidence to suggest that the effect of intervention on birth weight is also dependent on the amount of smoking prior to intervention.     

Effects of Bariatric Surgery on Maternal and Infant Outcomes of Pregnancy—An Evidence Analysis Center Systematic Review

BackgroundWhile obesity presents specific acute and long-term risks to the pregnant woman and her offspring, the effects of bariatric surgery on pregnancy outcomes are undetermined.ObjectiveA systematic review was performed according to the Academy of Nutrition and Dietetics Evidence Analysis Library process to determine the effects of bariatric surgery on both maternal and infant health outcomes of pregnancy.DesignA comprehensive literature search of PubMed was conducted to identify studies published from years 2000 to 2015 that examined the health effects of pregnancy after bariatric surgery. Experimental studies and observational studies with a control group were included.Main outcome measuresOutcomes of interest were gestational weight gain, maternal complications (ie, gestational diabetes, pre-eclampsia, eclampsia, hypertension, and postpartum hemorrhage), miscarriage and/or stillbirth, cesarean section, birth weight in grams, birth weight in categories (ie, macrosomia, low birth weight, small for gestational age, and large for gestational age), gestational age and preterm birth, infant illness and complications (ie, perinatal death, admission to neonatal intensive care unit, neonatal illness, and congenital malformation rates), and Apgar scores.ResultsThirteen of 246 studies were included. Compared to body mass index–matched controls without surgery, bariatric surgery before pregnancy reduced infant birth weight in grams, with no effect on total maternal gestational weight gain or Apgar scores. Surgery did not increase risk of adverse outcomes, such as miscarriage and/or stillbirth, preterm birth, or infant complications. Effects of surgery on maternal complications, infant birth weight categories, and surgical delivery rates were inconsistent.ConclusionsBariatric surgery is a successful treatment of maternal obesity, but certain surgery-specific risks may exist. More data are needed to determine clinical guidelines. The long-term effects of surgery on pregnancy outcomes are unknown.     

Legacy for Children

ABSTRACT: BACKGROUND: One in five Americans under age 18 lives in a family below the Federal poverty threshold. These more than 15 million children are at increased risk of a wide variety of adverse long-term health and developmental outcomes. The early years of life are critical to short- and long-term health and well-being. The Legacy for ChildrenTM model was developed in response to this need and marries the perspectives of epidemiology and public health to developmental psychology theory in order to better address the needs of children at environmental risk for poor developmental outcomes.Methods/designThe Legacy for ChildrenTM group-based parenting intervention model was evaluated as a pair of randomized controlled trials among low-income families in Miami and Los Angeles. The study was designed to allow for site-stratified analysis in order to evaluate each model implementation separately. Evaluation domains include comprehensive assessments of family, maternal, and child characteristics, process outcomes, and prospective programmatic cost. Data collection began prenatally or at birth and continues into school-age. DISCUSSION: The societal costs of poor developmental outcomes are substantial. A concerted effort from multiple sectors and disciplines, including public health, is necessary to address these societal concerns. Legacy uses a public health model to engage parents and promote overall child well-being in families in poverty through rigorous evaluation methodologies and evidence-based intervention strategies. This study collects rich and modular information on maternal and child outcomes, process, and cost that will enable a detailed understanding of how Legacy works, how it can be refined and improved, and how it can be translated and disseminated. Taken together, these results will inform public policy and help to address issues of health disparities among at-risk populations.Trial registrationNCT00164697.     

First time mothers' anxiety and depressive symptoms across the transition to motherhood: associations with maternal and environmental characteristics

The aim of this study was to examine demographic, environmental, belief, and personality factors related to maternal well-being as a part of a comprehensive project. In this study, maternal well-being was measured as prenatal anxiety and postnatal depression. A total of 200 pregnant women participated in this study. Women were included who were married, pregnant with a first child, working full time before conception and over the age of 20 years. The participants were selected from university hospitals and birth clinics in Ankara, Turkey. Participants were interviewed at 6-8 months of pregnancy and at 6-8 months after the birth. Each interview included structured items to measure relevant variables and lasted approximately 45-60 minutes. Results revealed that in the prenatal period lower maternal income, self-esteem and self-efficacy were significantly associated with prenatal maternal anxiety. In the postnatal period, maternal depressive symptoms were significantly associated with unplanned pregnancy, higher anxiety, perceived lower satisfaction with paternal physical support, and negative maternal attitudes toward employment. Findings indicated that prenatal high anxiety might be an adverse risk factor for postnatal well-being of mothers. In conclusion, both common and culture-specific factors related to prenatal and postnatal maternal well-being might assist with maternity and early care policies in this culture.     

Jail incarceration and birth outcomes

This study examined the relationships between jail incarceration during pregnancy and infant birth weight, preterm birth, and fetal growth restriction. We used multivariate regression analyses to compare outcomes for 496 births to women who were in jail for part of pregnancy with 4,960 Medicaid-funded births as matched community controls. After adjusting for potential confounding variables, the relationship between jail incarceration and birth outcomes was modified by maternal age. Relative to controls, women incarcerated during pregnancy had progressively higher odds of low birth weight and preterm birth through age 39 years; conversely, jail detainees older than 39 years were less likely than controls to experience low birth weight or preterm birth. For women in jail at all ages, postrelease maternity case management was associated with decreased odds of low birth weight, whereas prenatal care was associated with decreased odds of preterm birth. Local jails are important sites for public health intervention. Efforts to ensure that all pregnant women released from jail have access to enhanced prenatal health services may improve perinatal outcomes for this group of particularly vulnerable women and infants.     

The influence of maternal childhood and adulthood social class on the health of the infant

The aim of this study is to investigate how maternal childhood and adulthood social class contribute to social inequalities in low birth weight, neonatal mortality and postneonatal mortality. In particular I consider the combined influence of childhood and adult class, and compare outcomes with regard to the time distance from birth. Analyses were performed on a large sample of Swedish births from 1973 to 1990, restricted to infants of women with both childhood and adult class, classified as manual or non-manual. Logistic regression is used to compare odds ratios for social classes. The results indicate that manual maternal childhood class is consistently associated with higher risks for low birth weight and neonatal mortality, even when adult class was adjusted for. The influence of adult class was greater than that of childhood class for all health outcomes. Compared to higher/middle non-manual workers, unskilled workers in the service sector and workers in the manufacturing sector displayed the highest odds ratios for all adverse health outcomes. When both childhood and adult class were taken into account, social differences were greater for low birth weight and neonatal mortality than for postneonatal mortality. Maternal childhood class had more influence on low birth weight and neonatal mortality than on postneonatal mortality. I conclude that maternal childhood and adulthood social class are both independently associated with inequalities in health-related birth outcomes, and that social differences are greater for health outcomes closer to birth.     

Effect of zinc supplementation on pregnancy and infant outcomes: a systematic review

Poor maternal zinc status has been associated with foetal loss, congenital malformations, intra-uterine growth retardation, reduced birth weight, prolonged labour and preterm or post-term deliveries. A meta-analysis completed in 2007 showed that maternal zinc supplementation resulted in a small but significant reduction in preterm birth. The purposes of this analysis are to update that previous review and expand the scope of assessment to include maternal, infant and child health outcomes. Electronic searches were carried out to identify peer-reviewed, randomised controlled trials where daily zinc supplementation was given for at least one trimester of pregnancy. The co-authors applied the study selection criteria, assessed trial quality and abstracted data. A total of 20 independent intervention trials involving more than 11,000 births were identified. The 20 trials took place across five continents between 1977 and 2008. Most studies assessed the zinc effect against a background of other micronutrient supplements, but five were placebo-controlled trials of zinc alone. The provided dose of supplemental zinc ranged from 5 to 50 mg/day. Only the risk of preterm birth reached statistical significance (summary relative risk 0.86 [95% confidence interval 0.75, 0.99]). There was no evidence that supplemental zinc affected any parameter of foetal growth (risk of low birth weight, birth weight, length at birth or head circumference at birth). Six of the 20 trials were graded as high quality. The evidence that maternal zinc supplementation lowers the risk of preterm birth was graded low; evidence for a positive effect on other foetal outcomes was graded as very low. The effect of zinc supplementation on preterm birth, if causal, might reflect a reduction in maternal infection, a primary cause of prematurity. While further study would be needed to explore this possibility in detail, the overall public health benefit of zinc supplementation in pregnancy appears limited.     

Health and safety intervention with first-time mothers

A health education program was evaluated which used child development specialists as home visitors and served a population of first-time mothers living in rural communities. The evaluation compared health and safety outcomes between intervention and control groups. The research staff, separate from the intervention staff, collected data in the homes of 156 intervention and 107 control mothers when the infants were 6 and 12 months old. Significant group differences were found on health and safety outcomes. As compared with controls, the intervention mothers (i) had safer homes; (ii) were more likely to use birth control, thus had fewer pregnancies since birth of their first child; (iii) reported smoking fewer cigarettes; (iv) knew more about effects of smoking on their child's health and (v) were more likely to use health department services. In sum, mothers who received early education home visits from child development specialists experienced positive health and safety outcomes. It is highly recommended that a program such as this be implemented as part of health delivery program with new mothers and infants.     

Demographic Characteristics,Health Behaviors Before and During Pregnancy,and Pregnancy and Birth Outcomes in Mothers with Different Pregnancy Planning Status

Studies on pregnancy intentions and their consequences have yielded mixed results. Here, we comprehensively analyzed the maternal characteristics, health behaviors before and during pregnancy, as well as pregnancy and birth outcomes, across three different pregnancy planning status in 861 women participating in an ongoing Asian mother-offspring cohort study. At 26–28 weeks’ gestation, the women’s intention and enthusiasm toward their pregnancy were used to classify their pregnancy into planned or unplanned, and unplanned pregnancy was further subdivided into mistimed or unintended. Data on maternal characteristics, health behaviors, and pregnancy outcomes up to that stage were recorded. After delivery, birth outcomes of the offspring were recorded. Linear and logistic regression analyses were performed. Overall, 56 % had a planned pregnancy, 39 % mistimed, and 5 % unintended. Compared to women who planned their pregnancy, women with mistimed pregnancy had higher body mass index and were more likely to have cigarette smoke exposure and less likely to have folic acid supplementation. At 26–28 weeks’ gestation, unintended pregnancy was associated with increased anxiety. Neonates of mistimed pregnancy had shorter birth length compared to those of planned pregnancy, even after adjustment for maternal baseline demographics. These findings suggest that mothers who did not plan their pregnancy had less desirable characteristics or health behaviors before and during pregnancy and poorer pregnancy and birth outcomes. Shorter birth length in mistimed pregnancy may be attributed to maternal behaviors before or in the early stages of pregnancy, therefore highlighting the importance of preconception health promotion and screening for women of child-bearing age.     

Estimating drowning deaths in Northern Iran using capture-recapture method

Health plays an important role in economic well-being. The relationship between poor health and poverty is multifaceted. Globally, reproductive health conditions are the second highest cause of ill health. This study uses district-level data from India to investigate how an index of maternal health care is impacted by the rate of poverty, and a development index based on the performance in electrification, sanitation and safe drinking water. The initial results from a linear regression model show that maternal health care improves by 0.617 percentage point for every 1 percentage point increase in development intervention but by only 0.078 percentage point for every 1 percentage point decline in poverty rate. After checking for possible simultaneity problem between maternal health care index (MHCI) and poverty rate, it is revealed that the low negative relationship between poverty and MHCI at the initial stage does not hold any more while the district development index continues to show the considerable and statistically significant impact. The findings underscore the need for direct government intervention in improving maternal health care in Indian districts.     

Explaining racial disparities in adverse birth outcomes: unique sources of stress for Black American women

The infant mortality rate for Black Americans in the US is more than twice the rate for White Americans, with similar racial disparities existing in rates of low birthweight and preterm delivery. Survivors of these adverse birth outcomes have poorer development and health in infancy, childhood, and adulthood. Increasingly, evidence suggests that maternal stress is an important risk factor for adverse birth outcomes. We offer a novel perspective on racial disparities in birth outcomes suggesting that Black American women are subject to unique sources of stress throughout their lives and particularly during pregnancy based on their multiple identities as women, Black, and pregnant. We draw on interdisciplinary work to examine three unique sources of stress for Black American women that elevate their risk for adverse birth outcomes: 1) abuses of Black American women by the medical system and issues of power in obstetrics that disadvantage Black American women; 2) contradictory societal pressures exerted on Black American women about whether they should have children; and 3) historical and contemporary stereotypes about Black American women related to sexuality and motherhood. We discuss implications of this analysis, including applications to research and intervention. Developing a better understanding of the experience of Black American women during pregnancy and throughout their lives offers insight into ways to reduce racial disparities in adverse birth outcomes and their lifelong consequences.     

Maternal nutrition and optimal infant feeding practices: executive summary

Much recent attention has been paid to the effect of the fetal environment on not only healthy birth outcomes but also long-term health outcomes, including a role as an antecedent to adult diseases. A major gap in our understanding of these relations, however, is the effect of maternal nutrition and nutrient transport on healthy fetal growth and development. In addition, this gap precludes evidence-based recommendations about how to best feed preterm infants. The biological role of the mother and the effect of her nutritional status on infant feeding extend to postnatal infant feeding practices. Currently, evidence is incomplete about not only the composition of human milk, but also the maternal nutritional needs to support extended lactation and the appropriate nutrient composition of foods that will be used to complement breastfeeding at least through the first year of life. Consequently, a conference, organized by the National Institute of Child Health and Human Development, the National Institutes of Health Office of Dietary Supplements, and the US Department of Agriculture Children's Nutrition Research Center was held to explore current knowledge and develop a research agenda to address maternal nutrition and infant feeding practices. These proceedings contain presentations about the effect of maternal nutrition and the placental environment on fetal growth and birth outcomes, as well as issues pertaining to feeding preterm and full-term infants.     

Socioeconomic domains and associations with preterm birth

Neighborhood socioeconomic effects on health have been estimated using multiple variables and indices. This inconsistent estimation approach makes comparison across geographic areas challenging. In this paper, we developed indices representing specific socioeconomic domains that can be reproduced in other areas to estimate elements of the neighborhood socioeconomic environment on health outcomes, specifically preterm birth. Using year 2000 U.S. census data and principal components analysis, socioeconomic indices were developed representing a priori - defined domains of education, employment, housing, occupation, poverty and residential stability. These socioeconomic indices were subsequently used in race-stratified multilevel logistic regression models of preterm birth in eight socioeconomically distinct study areas in the U.S. Maternal residence was obtained from birth records and was geocoded to census tracts. In maternal age and education adjusted models, living in tracts with high unemployment, low education, poor housing, low proportion of managerial or professional occupation and high poverty was associated with increased odds of preterm birth for non-Hispanic white women at most sites. Among non-Hispanic black women, similar associations were noted for tract-level low education, high unemployment, low occupation, and high poverty, but the effect estimates were generally smaller than those seen for white women. Increasing amounts of residential stability were not associated with preterm birth in these analyses. We combined the domain estimates across the eight study sites to produce pooled effect estimates for the socioeconomic domains on preterm birth. The research reported here suggests that specific neighborhood-level socioeconomic features may be especially influential to health outcomes. These socioeconomic domains represent potential targets for intervention or policy efforts designed to improve maternal and child health and reduce health disparities.     

Birth models of care and intervention rates: The impact of birth centres

Birth centres offer a midwifery-led model of care which supports a non-medicalised approach to childbirth. They are often reported as having low rates of birth intervention, however the precise impact is obscured because less disadvantaged mothers with less complex pregnancies, and who prefer and often select little intervention, are more likely to choose a birth centre. In this paper, we use a methodology that purges the impact of these selection effects and provides a causal interpretation of the impact of birth centres on intervention outcomes. Using administrative birth data on over 364,000 births in Australia’s most populous state between 2001 and 2012, we implement an instrumental variables framework to address confounding factors influencing choice of birth setting. We find that giving birth in a birth centre results in significantly lower probabilities of intervention, and that critically, this impact has been increasing over time. Our estimates are larger than those in existing studies, reflecting our newer data, diverging intervention rates across birth settings, and our accounting for important selection effects. The results emphasise the greater role of birth centres in delivering on policy priorities which include greater maternal autonomy, lower intervention rates, and lower health system costs.     

The impact of early age at first childbirth on maternal and infant health

The objective of this review was to assess whether early age at first childbirth is associated with increased risk of poor pregnancy outcomes. Early age at childbirth is variously defined in studies of its effect on maternal and infant health. In this systematic review, we limit analysis to studies of at least moderate quality that examine first births among young mothers, where young maternal age is defined as low gynaecological age (≤ 2 years since menarche) or as a chronological age ≤ 16 years at conception or delivery. We conduct meta-analyses for specific maternal or infant health outcomes when there are at least three moderate quality studies that define the exposure and outcome in a similar manner and provide odds ratios or risk ratios as their effect estimates. We conclude that the overall evidence of effect for very young maternal age (<15 years or <2 years post-menarche) on infant outcomes is moderate; that is, future studies are likely to refine the estimate of effect or precision but not to change the conclusion. Evidence points to an impact of young maternal age on low birthweight and preterm birth, which may mediate other infant outcomes such as neonatal mortality. The evidence that young maternal age increases risk for maternal anaemia is also fairly strong, although information on other nutritional outcomes and maternal morbidity/mortality is less clear. Many of the differences observed among older teenagers with respect to infant outcomes may be because of socio-economic or behavioural differences, although these may vary by country/setting. Future, high quality observational studies in low income settings are recommended in order to address the question of generalisability of evidence. In particular, studies in low income countries need to consider low gynaecological age, rather than simply chronological age, as an exposure. As well, country-specific studies should measure the minimum age at which childbearing for teens has similar associations with health as childbearing for adults. This 'tipping point' may vary by the underlying physical and nutritional health of girls and young women.     

An Exploration of Maternal Intimate Partner Violence Experiences and Infant General Health and Temperament

Objectives While the women’s health consequences of intimate partner violence have received much research attention, less is known about how maternal abuse experiences affect infant health and well-being. Existing studies have also been unable to examine specific types of intimate partner violence such as psychological aggression, physical abuse, and sexual coercion. This secondary data analysis explored the prevalence, patterns, and types of intimate partner violence within a large cohort of mothers and explored the relationship between maternal intimate partner violence experiences and infant’s general health and temperament at 1 year of age. Methods Existing data were drawn from the Fragile Families and Child Wellbeing study which collected data through surveys conducted shortly after the infant’s birth (baseline) and at 1 year of age (follow-up). Records from 4,141 mothers recruited from 75 hospitals, in 20 cities, in the US were used. Bivariate and multivariate regression analyses were conducted. Results Results show high rates of intimate partner violence. Maternal reports of any intimate partner violence at baseline or follow-up were both significantly associated with increased odds of less than excellent infant general health and difficult temperament. Independent examination of psychological, physical, and sexual abuse revealed differential relationships between the types of intimate partner violence and infant health outcomes. Conclusions Results from this study contribute to our understanding of the infant health threats associated with maternal intimate partner violence experiences. Additional research addressing the complex relationship between maternal abuse experiences and infant health and specific intervention implications is warranted.     

Interventions with vitamins B6, B12 and C in pregnancy

The water-soluble vitamins B6, B12 and C play important roles in maternal health as well as fetal development and physiology during gestation. This systematic review evaluates the risks and benefits of interventions with vitamins B6, B12 and C during pregnancy on maternal, neonatal and child health and nutrition outcomes. Relevant publications were identified by searching PubMed, Popline and Web of Science databases. Meta-analyses were conducted for outcomes where results from at least three controlled trials were available. Potential benefits of vitamin B6 supplementation were reduction in nausea and vomiting, improvement in dental health, and treatment of some cases of anaemia. In meta-analysis based on three small studies, vitamin B6 supplementation had a significant positive effect on birthweight (d = 217 g [95% confidence interval (CI) 130, 304]). Interventions with vitamin C alone or combined with vitamin E did not systematically reduce the incidence of pre-eclampsia, premature rupture of membranes, or other adverse pregnancy outcomes. In meta-analyses, vitamins C and E increased the risk of pregnancy-related hypertension (relative risk 1.10 [95% CI 1.02, 1.19]). Effects of vitamin B6 or C intervention on other neonatal outcomes, including preterm birth, low birthweight, and perinatal morbidity and mortality, were not significant. Data on child health outcomes were lacking. Despite the prevalence of vitamin B12 deficiency amongst populations with limited intake of animal source foods, no intervention trials have evaluated vitamin B12 supplementation before or during pregnancy. In conclusion, existing evidence does not justify vitamin C supplementation during pregnancy. Additional studies are needed to confirm positive effects of vitamin B6 supplementation on infant birthweight and other outcomes. While vitamin B12 supplementation may reduce the incidence of neural tube defects in the offspring based on theoretical considerations, research is needed to support this hypothesis.     

Race differences in the proportion of low birth weight attributable to maternal cigarette smoking in a low-income population

PURPOSE: To quantify race differences in the public health impact of maternal cigarette smoking on infant birth weight and to estimate the proportion of low birth weight births that could be prevented by maternal smoking cessation. DESIGN: A cohort that consisted of 77,751 mother-infant pairs was evaluated retrospectively. SETTING: Statewide study of Women, Infants and Children participants in North Carolina. SUBJECTS: African-American and non-Hispanic white women who delivered a single live infant during 1988, 1989, or 1990. MEASURES: Logistic regression estimates of the relative risk of low birth weight births for smokers were used to calculate adjusted population attributable risk percentages for smoking. Separate population attributable risk percentages were calculated for total low birth weight, moderately low birth weight, and very low birth weight, and all estimates were adjusted for prepregnancy body mass index, gestational weight gain, age, education, parity, and timing of entry into prenatal care. RESULTS: Non-Hispanic whites had a much higher prevalence of smoking and were heavier smokers than African-Americans. For both moderately low birth weight and very low birth weight, the population attributable risk percentages for smoking were twice as high for non-Hispanic whites than for African-Americans. Overall, after adjustment, 30.7% of low birth weight births among non-Hispanic whites and 14.4% of low birth weight births among African-Americans were attributable to smoking. CONCLUSIONS: Although the public health impact of maternal cigarette smoking on infant birth weight was twice as high for non-Hispanic whites as for African-Americans in this low-income population, smoking cessation by all low-income pregnant women would result in significant improvements in infant health and well-being.