Biomarkers in assessing residential insecticide exposures during pregnancy and effects on fetal growth.

The Columbia Center for Children's Environmental Health is using a combination of environmental and biologic measures to evaluate the effects of prenatal insecticide exposures among urban minorities in New York City. Of the 571 women enrolled, 85% report using some form of pest control during pregnancy and 46% report using exterminators, can sprays, and/or pest bombs. Chlorpyrifos, diazinon, and propoxur were detected in 99.7-100% of 48-h personal air samples collected from the mothers during pregnancy (n = 394) and in 39-70% of blood samples collected from the mothers (n = 326) and/or newborns (n = 341) at delivery. Maternal and newborn blood levels are similar and highly correlated (r = 0.4-08, P < 0.001). Levels of insecticides in blood samples and/or personal air samples decreased significantly following the 2000-2001 U.S. Environmental Protection Agency's regulatory actions to phase out residential use of chlorpyrifos and diazinon. Among infants born prior to 1/1/01, birth weight decreased by 67.3 g (95% confidence interval (CI) -116.6 to -17.8, P = 0.008) and birth length decreased by 0.43 centimeters (95% CI, -0.73 to -0.14, P = 0.004) for each unit increase in log-transformed cord plasma chlorpyrifos levels. Combined measures of (ln)cord plasma chlorpyrifos and diazinon (adjusted for relative potency) were also inversely associated with birth weight and length (P 0.8). Results support recent regulatory action to phase out residential uses of these insecticides.

Developmental effects of exposure to environmental tobacco smoke and material hardship among inner-city children.

Because of the growing concern that exposures to airborne pollutants have adverse effects on fetal growth and early childhood neurodevelopment, and the knowledge that such exposures are more prevalent in disadvantaged populations, we assessed the joint impact of prenatal exposure to environmental tobacco smoke (ETS) and material hardship on the 2-year cognitive development of inner-city children, adjusted for other sociodemographic risks and chemical exposures. The purpose was to evaluate the neurotoxicant effects of ETS among children experiencing different degrees of socioeconomic disadvantage, within a minority population. The sample did not include children exposed to active maternal smoking in the prenatal period. Results showed significant adverse effects of prenatal residential ETS exposure and the level of material hardship on 2-year cognitive development, as well as a significant interaction between material hardship and ETS, such that children with both ETS exposure and material hardship exhibited the greatest cognitive deficit. In addition, children with prenatal ETS exposure were twice as likely to be classified as significantly delayed, as compared with nonexposed children. Postnatal ETS exposure in the first 2 years of life did not contribute independently to the risk of developmental delay, over and above the risk posed by prenatal ETS exposure. The study concluded that prenatal exposure to ETS in the home has a negative impact on 2-year cognitive development, and this effect is exacerbated under conditions of material hardship in this urban minority sample.

The contribution of maternal age to racial disparities in birthweight: a multilevel perspective.

OBJECTIVES: This study assessed the contribution of age and other risk factors to racial disparities in rates of moderately low birthweight (MLBW; 1500-2499 g) and very low birthweight (VLBW; <1500 g). METHODS: Logistic regression models were developed to determine the effects on MLBW and VLBW of maternal age, race, and poverty, adjusting for birth order, smoking, substance abuse, marital status, and educational level. The sample consisted of 158 174 singleton births to US-born African American and White women in New York City between 1987 and 1993. RESULTS: The effects of maternal age on MLBW varied by race and poverty, with the most extreme effects among poor African American women. The effects of maternal age on VLBW also varied by race, but these effects were not moderated by poverty. Community poverty had a significant effect on MLBW among African American women, but no effect on VLBW. The adverse effect of older maternal age on MLBW and VLBW did not vary with community poverty. CONCLUSIONS: Older maternal age is associated with reduced birthweight among infants born to African American women, and the age effect is exacerbated by individual poverty.

Bacterial vaginosis: a public health problem for women.

Bacterial vaginosis (BV) remains a moderately prevalent condition with clearly observed links to adverse reproductive, gynecological, and other outcomes in women, including human immunodeficiency virus infection. Because of inconsistent findings from clinical studies concerning BV's etiologic role, no definitive policies with respect to screening and treatment have yet been established. Of concern is the high, unexplained prevalence of BV among African-American women, who are also at extremely high risk for preterm birth. The complexity of the sociodemographic picture challenges the field of public health to continue to explore the role of BV and its relationship to a whole host of social and biomedical conditions that may contribute to adverse health outcomes among society's most vulnerable members. Future decisions about screening and treatment, currently based on the biomedical model, may need to take into consideration issues of social context and expanded views of causality if we are to better understand and eliminate those factors that place individual women at risk of adverse outcomes, as well as the conditions that underlie racial and ethnic disparities in health.

Birth outcomes for Asian-American adolescents: a high-risk group?

OBJECTIVE: To explore the risks of moderately low (MLBW) and very low birthweight (VLBW) among Asian-American women, with particular attention to adolescent mothers. METHODS: Data from birth certificates on 28,477 Asian women who gave birth in New York City between 1987 and 1993 were used to calculate percentages of MLBW and VLBW, and logistic regression analysis was used to estimate odds ratios for maternal age, country of origin, and other risk factors. RESULTS: Adolescents had elevated risks for both MLBW and VLBW, and most of this risk was attributed to the high prevalence of maternal sociodemographic risk factors among adolescents, as compared to older women. A significantly elevated risk of VLBW was found for teens who were born in the United States, suggesting a worrisome picture for second-generation Asian Americans.

Ethnic differences in birthweight: the role of lifestyle and other factors.

OBJECTIVES: The purpose of this study was to expand the search for risk factors for low birthweight and to find new explanations for the ethnic-group disparities in birth outcomes. METHODS: The subjects were 1150 pregnant women from six ethnic groups (African American, Chinese, Dominican, Puerto Rican, Mexican, and White) who received prenatal care at clinics in New York and Chicago between December 1987 and December 1989. Two interviews were conducted during the second and third trimesters of pregnancy. RESULTS: The study, after controlling for poverty and other birthweight correlates, showed that living in public housing and believing that chance plays a major role in determining one's health status were negatively associated with birthweight. Having a stable residence was positively related to birthweight. Material hardship, social adversity, perceived racial discrimination, physical abuse, anxiety, and depression were not associated with birthweight. CONCLUSIONS: The negative role of an impoverished living environment and feelings of helplessness, as well as the positive role of having a stable form of social support, suggest new directions for research on the causes of low birthweight and the ethnic disparities in US birth outcomes.

Nine-year outcome of the Vermont intervention program for low birth weight infants.

Twenty-four low birth weight children who had received an experimental intervention (LBWE) during the neonatal period, 31 control children who had received no treatment (LBWC), and 36 normal birth weight children were compared. The intervention involved seven hospital sessions and four home sessions in which a nurse helped mothers adapt to their LBW babies. At age 9, LBWE children scored significantly higher than LBWC children on the Kaufman Mental Processing Composite, Sequential, Simultaneous, Achievement, Arithmetic, and Riddles scales, after statistical adjustments for socioeconomic status. The LBWE children had also advanced more rapidly in school than had LBWC children. Parent (Child Behavior Checklist) and teacher (Teacher's Report Form) ratings of school functioning were more favorable for LBWE than LBWC children, with especially strong effects on Teacher's Report Form scores for academic performance and the attention problems syndrome. At age 9, LBWE children were not significantly inferior to normal birth weight children on any measure. These results bear out a progressive divergence between the LBWE and LBWC children that first became statistically significant in cognitive scores at age 3. The findings suggest that the intervention prevented cognitive lags among LBW children and that this eventually had a favorable effect on academic achievement, behavior, and advancement in school. The progression from no significant differences between LBWE and LBWC children on early cognitive and achievement scores to significant and pervasive differences in later functioning argues for long-term follow-up periods to evaluate properly the power of behavioral interventions to compensate for biological risks.

Seven-year outcome of the Vermont Intervention Program for Low-Birthweight Infants.

We compared 24 low-birthweight subjects of an experimental intervention (LBWE), 32 no-treatment controls (LBWC), and 37 normal birthweight (NBW) subjects. The intervention involved 7 hospital sessions and 4 home sessions in which a nurse helped mothers adapt to their LBW babies. At age 7, LBWE scored significantly higher than LBWC on the Kaufman Mental Processing Composite (p less than .001), Sequential (p = .02), and Simultaneous (p = .001) Scales, after statistical adjustments for socioeconomic status. LBWE did not differ from NBW (F less than 1). These results bear out a divergence between the LBWE and LBWC that first became statistically significant at age 3. The findings suggest that the intervention prevented cognitive lags among LBW children, and that long-term follow-ups are needed to evaluate the developmental effects of efforts to overcome major biological and environmental risks.

Determinants of maternal child-rearing attitudes.

This study investigated the correlates of negative attitudes toward child-rearing among low-income urban black and Hispanic mothers. Using a randomized block procedure, 144 adolescents and 139 adults giving birth to healthy infants at a large metropolitan hospital were recruited. All consenting women were interviewed in the hospital within 2 days after delivery, using standardized measures of child-rearing attitudes, self-esteem, depressive symptoms, social support, and cognitive ability. Hierarchical multiple regression analyses showed that depressive symptoms, cognitive ability, and two demographic characteristics (maternal age and spoken language) accounted for 42.4% of the variance in negative childrearing attitudes during the postpartum period. The contributions of social support and self-esteem were no longer significant when the effects of the other psychosocial factors were taken into consideration simultaneously. The utility of early assessment of maternal attitudes as a marker for maternal risk status is addressed. The adaptive function of maternal attitudes and the implications for child-rearing practices are discussed in relation to the process of acculturation.

Psychosocial attributes and life experiences of disadvantaged minority mothers: age and ethnic variations.

This study examined age and ethnic differences in psychosocial factors among hispanic (n = 210) and black (n = 73) low-income mothers within 2 days after delivery. The sample included 45 black and 99 hispanic adolescents (less than 19 years) and 139 adult controls (greater than or equal to 20 years) giving birth on the service ward at a large metropolitan hospital, excluding mothers and infants with high parity or adverse perinatal conditions. Multivariate and univariate analyses, with parity covaried, revealed age effects including earlier menarche, more school grade retention, and more perceived social support among teens. No age differences were found in child-rearing attitudes, self-esteem, or depressive symptoms. Black mothers reported more social support, higher self-esteem, and less strict child-rearing attitudes than hispanics. Analyses within the hispanic sample revealed Dominican/Puerto Rican group differences in measures of family structure and child-rearing attitudes, but only small differences in social support. Ethnocultural differences between blacks and hispanics and between the two hispanic subgroups are considered in relation to the process of acculturation.

The Mother-Infant Transaction Program. The content and implications of an intervention for the mothers of low-birthweight infants.

A brief, economic neonatal intervention based on the transactional model of development and influenced predominantly by the conceptual design of the Neonatal Behavioral Assessment Scale was implemented in an intensive care nursery with the mothers of a group of low-birthweight infants. The development of the intervention group was compared with that of a similar group of low-birthweight infants who did not receive the intervention and contrasted with that of a group of normal-birthweight infants. The intervention had a significant effect on maternal adjustment and perception of the infant at 6 months. No significant effect on infant cognitive development was apparent until 36 months (that is, 31 months after the intervention had ceased). The intervention effect was even more significant at 48 months. It appeared that the two low-birthweight groups had progressively diverged after 12 months, the intervention group rising until it approximated the normal-birthweight group in cognitive development, whereas the low-birthweight control group deteriorated. The economical nature of the MITP, its unique (although delayed) benefits, and the apparent durability of the intervention effect, suggest that this intervention program has important theoretical and practical implications and potentially far-reaching applications.

Minimizing adverse effects of low birthweight: four-year results of an early intervention program.

The outcome of an early intervention program for low-birthweight (LBW) infants was examined in this study. The intervention consisted of 11 sessions, beginning during the final week of hospitalization and extending into the home over a 3-month period. The program aimed to facilitate maternal adjustment to the care of a LBW infant, and, indirectly, to enhance the child's development. Neonates weighing less than 2,200 grams and under 37 weeks gestational age were randomly assigned to experimental or control conditions. A full-term, normal birthweight (NBW) group served as a second control. 6-month analyses of dyads who completed all assessments over a 4-year period (N's = 25 LBW experimental, 29 LBW control, and 28 NBW infant-mother dyads) showed that the experimental group mothers reported significantly greater self-confidence and satisfaction with mothering, as well as more favorable perception of infant temperament than LBW control group mothers. A progressive divergence between the LBW experimental and LBW control children on cognitive scores culminated in significant group differences on the McCarthy GCI at ages 36 and 48 months, when the LBW experimental group caught up to the NBW group. Possible explanations for the observed delay in the emergence of intervention effects on cognitive development and the mediating role of favorable mother-infant transactional patterns are discussed in light of recent evidence from the literature.

PIP: The outcome of an early intervention program for low-birthweight (LBW) infants was examined in this study. The intervention consisted of 11 sessions, beginning during the final week of hospitalization and extending into the home over a 3-month period. The program aimed to facilitate maternal adjustment to the care of a LBW infant, and indirectly, to enhance the child's development. Neonates weighing less than 2,200 grams and under 37 weeks gestational age were randomly assigned to experimental or control analysis of dyads who completed all assessments over a 4-year period (N's = 25 LBW experimental, 29 LBW control, and 28 NBW infant-mother dyads) showed that the experimental group mothers reported significantly greater self-confidence and satisfaction with mothering, as well as more favorable perception of infant temperament than LBW control group mothers. A progressive divergence between the LBW experimental and LBW control children on cognitive scores culminated in significant group differences on the McCarthy GCI at ages 36 and 48 months, when the LBW experimental group caught up to the NBW group. Possible explanations for the observed delay in the emergence of intervention effects on cognitive development and the mediating role of favorable mother-infant transactional patterns are discussed in light of recent evidence from the literature. These findings support a transactional model for facilitating mother-infant interactions. A logical next step would be to replicate the intervention program on a different sample of infants considered to be at biological risk. The studies were conducted at Medical Center Hospital in Vermont.