Birth characteristics and subsequent risk for breast cancer in very young women

There is growing evidence that prenatal exposures may influence later breast cancer risk. This matched case-control study used linked New York State birth and tumor registry data to examine the association between birth characteristics and breast cancer risk among women aged 14-37 years. Cases were women diagnosed with breast cancer between 1978 and 1995 who were also born in New York after 1957 (n = 484). For each case, selected controls were the next six liveborn females with the same maternal county of residence. The authors found a J-shaped association between birth weight and breast cancer risk, and very high birth weight (> or =4,500 g) was associated with the greatest elevation in risk (adjusted odds ratio (OR) = 3.10, 95% confidence interval (CI): 1.18, 7.97). The association of maternal age with breast cancer risk was also J-shaped, with maternal age of more than 24 years showing a positive, linear association (adjusted OR = 1.94, 95% CI: 1.18, 3.18 for maternal age > or =35 vs. 20-24 years; p for trend = 0.02). In contrast, women born very preterm had a lower risk (adjusted OR = 0.11, 95% CI: 0.02, 0.79 for gestational age <33 vs. > or =37 weeks). These findings support a role for early life factors in the development of breast cancer in very young women.     

A case-control study of maternal smoking and congenital malformations

We conducted a population-based case-control study to assess the association between maternal smoking during pregnancy and the risk of giving birth to a child with a congenital malformation. Cases were all singleton livebirths with a congenital malformation recorded on the 1984-1986 Washington State Birth Records (n = 3284). The smoking histories of these mothers were compared to a randomly selected group of mothers with a singleton livebirth of a child without a malformation during these same years (n = 4500). When all malformations were taken as a group, there was no association with maternal smoking (relative risk (RR) = 1.0, 95% CI 0.9-1.1). However, increased risks were observed for a number of specific malformations, including microcephalus (RR = 2.0, 95% CI 1.0-4.0), cleft defects (RR = 1.4, 95% CI 1.0-2.0), and club foot (RR = 1.4, 95% CI 1.0-2.0). We did not find any association with Down's syndrome (RR = 0.8 95% CI 0.5-1.3) or any other malformation. We conclude that maternal smoking during pregnancy may be associated with an increased risk for some malformations.     

Risk factors for neonatal seizures: a population-based study, Harris County, Texas, 1992-1994.

Risk factors for neonatal seizures were evaluated in 116,048 infants born between 1992 and 1994 to residents of Harris County, Texas; 207 of these infants were diagnosed with clinical neonatal seizures. Information was obtained from the infant's birth certificate to assess the relation between seizures and birth weight, gender, ethnicity, place of birth, mother's age, method of delivery, parity, and multiple births. These factors were evaluated by univariate and multivariate analysis using logistic regression. For preterm infants, a birth weight of <1,500 g was the strongest risk factor (relative risk (RR) = 9.1, 95% confidence interval (CI): 4.7, 17.5), followed by birth in a private/university hospital (RR = 2.8, 95% CI: 1.5, 5.0) and male gender (RR = 1.8, 95% CI: 1.0, 3.4). For term infants, significant risk factors included birth by cesarean section (RR = 2.2, 95% CI: 1.5, 3.2), small birth weight for gestational age (RR = 1.9, 95% CI: 1.2, 2.9), birth in a private/university hospital (RR = 1.8, 95% CI: 1.1, 3.0), and maternal age of 18-24 compared with 25-29 years (RR = 1.6, 95% CI: 1.1, 2.3). Birth by assisted vaginal delivery and primiparity were marginally significant for term infants. Birth weight is a significant risk factor for neonatal seizures. The role of perinatal complications warrants further evaluation.     

A case-control study of maternal smoking and congenital malformations

Summary. We conducted a population-based case-control study to assess the association between maternal smoking during pregnancy and the risk of giving birth to a child with a congenital malformation. Cases were all singleton livebirths with a congenital malformation recorded on the 1984–1986 Washington State Birth Records (n = 3284). The smoking histories of these mothers were compared to a randomly selected group of mothers with a singleton livebirth of a child without a malformation during these same years (n = 4500). When all malformations were taken as a group, there was no association with maternal smoking (relative risk (RR) = l.0, 95% CI 0.9–1.1). However, increased risks were observed for a number of specific malformations, including microcephalus (RR = 2.0, 95% CI 1.0–4.0), cleft defects (RR=1.4, 95% CI 1.0–2.0), and club foot (RR= 1.4, 95% CI 1.0–2.0). We did not find any association with Down's syndrome (RR=0.8, 95% CI 0.5–1.3) or any other malformation. We conclude that maternal smoking during pregnancy may be associated with an increased risk for some malformations.     

Urban and rural suicide differentials in migrants and the Australian-born, New South Wales, Australia 1985--1994.

We estimated risk of suicide in adults in New South Wales (NSW) by sex, country of birth and rural/urban residence, after adjusting for age; we also examined youth suicide (age 15-24 years). The study population was the entire population of NSW, Australia, aged > or =15 years during the period 1985-1994. Poisson regression was used to examine the relationship between predictor variables and the risk of suicide, with the focus on migrant status and area of residence. A significantly higher risk of suicide was found in male migrants from Northern Europe and Eastern Europe/former USSR, compared to Australian-born males; a significantly lower suicide risk occurred in males from Southern Europe, the Middle East and Asia. In female migrants, those from UK/Eire, Northern Europe, Eastern Europe/former USSR and New Zealand exhibited a significantly higher risk of suicide compared to Australian-born females. A significantly lower risk of suicide occurred in females from the Middle East. Male migrants overall were at significantly lower risk of suicide than the Australian-born, while female migrants overall had a significantly higher risk of suicide than Australian-born females. Among migrant males overall, the rural-urban suicide risk differential was significantly higher for those living in non-metropolitan areas (RR = 1.9; 95% CI: 1.7-2.1). Suicide risk was significantly higher in non-metropolitan male immigrants from the UK/Eire (RR = 1.4; 95% CI: 1.1-1.7), Southern Europe (RR = 1.7; 95% CI: 1.2-2.4), Northern/Western Europe (1.5; 95% CI: 1.2-1.9), the Middle East (RR = 3.8; 95% CI: 1.9-7.8), New Zealand (RR = 1.4; 95% CI: 1.0-1.8) and 'other' (RR = 2.6; 95% CI: 1.9-3.5), when compared to their urban counterparts. There was no statistically significant difference in suicide risk between rural and urban Australian-born males. For female suicide, significantly lower risk was found in female immigrants living in non-metropolitan areas who were from Northern/Western Europe (RR = 0.7; 95% CI: 0.4-0.96), as well as the Australian-born (RR = 0.7; 95% CI: 0.6-0.8), when compared to their urban counterparts. The non-metropolitan/metropolitan relative risk for suicide in female migrants overall was not significantly different from one. Among male youth there was a significantly higher suicide risk in non-metropolitan areas, with a relative risk estimate of 1.4 for Australian-born youth (95% CI: 1.2-1.5) and 1.7 for migrant youth (95% CI: 1.2-2.4), when compared with metropolitan counterparts. We conclude that suicide among migrant males living in non-metropolitan areas accounts for most of the excess of male suicide in rural NSW, and the significantly lower risk of suicide for non-metropolitan Australian-born women does not apply to migrant women.     

Cocaine use during pregnancy: perinatal outcomes

The relation between maternal cocaine use and perinatal outcomes was investigated among 17,466 non-Asian singleton deliveries in 1988 from the University of Illinois Perinatal Network data base in the metropolitan Chicago area. Elevated adjusted relative risks (RR) of low birth weight (RR = 2.8, 95% confidence interval (CI) 2.2-3.7), prematurity (RR = 2.4, 95% CI 1.9-3.1), abruptio placentae (RR = 4.5, 95% CI 2.4-8.5), and perinatal death (RR = 2.1, 95% CI 1.1-4.0) were observed for "any" cocaine users (n = 408) compared with women who did not use cocaine or any other drugs or alcohol (n = 17,058). There was an increased (although unstable) risk of intrapartum placenta previa not previously reported (RR = 2.3, 95% CI 1.0-5.1). The relative risk of small-for-gestational-age births for cocaine users who did not smoke (RR = 3.4, 95% CI 1.8-6.5) was greater than that for cocaine users who did (RR = 2.1, 95% CI 1.1-4.1). Irrespective of smoking status, cocaine use during pregnancy increased the risk of small-for-gestational-age births.     

The relation between multiple births and maternal risk of breast cancer.

Data from two case-control studies conducted in New York State during 1982-1986 were used to examine the relation between multiple births and the maternal risk of breast cancer. The cases were 2,561 women between 20 and 79 years of age with a diagnosis of primary breast cancer. Controls (n = 2,616) were selected from driver's license files and matched to cases by year of birth and county of residence. The odds ratio for any multiple birth was 0.94 (95% confidence interval (CI) 0.56-1.56) in women less than 55 years of age and 0.95 (95% CI 0.62-1.46) in women aged 55-79 years. A previous study had shown a multiple last birth to be protective against breast cancer in women less than 55 years of age (odds ratio (OR) = 0.60, 95% CI 0.43-0.85). A decreased risk of breast cancer was also observed for this age group in the present study, but the magnitude of the effect was not as strong and the confidence interval included unity (OR = 0.85, 95% CI 0.43-1.68). A logistic model that controlled for age at first pregnancy, number of live births, age, and county of residence increased the odds ratio to 0.97 for a multiple last birth. The current study does not support an association between multiple births and maternal risk of breast cancer.     

Associations of birth weight and length, childhood size, and smoking with bone fractures during growth: evidence from a birth cohort study

Little information exists on risk factors associated with bone fractures during childhood and adolescence. This 1972/1973-1990/1991 New Zealand study examined the influence of birth size, height and weight throughout growth, smoking, breastfeeding, and sports participation on the risk of fracture in participants of the Dunedin Multidisciplinary Health and Development Study. Information on height, weight, fracture status, and lifestyle was collected at birth and at ages 3, 5, 7, 9, 11, 13, 15, and 18 years from parents and/or participants. Study members sustained 229 (girls) and 393 (boys) fractures between birth and age 18 years. Fracture risk was elevated (per standard deviation unit increase) in relation to birth length (prepubertal fractures only) (risk ratio (RR) = 1.28, 95% confidence interval (CI): 1.04, 1.58), weight at age 3 years (RR = 1.14, 95% CI: 1.03, 1.27), weight from ages 5 to 18 years (RR = 1.15, 95% CI: 1.03, 1.28), height at age 3 years (RR = 1.13, 95% CI: 1.01, 1.26), and height from ages 5 to 18 years (RR = 1.13, 95% CI: 1.02, 1.24). Birth weight, maternal smoking, breastfeeding, and sports participation had no significant effect on fracture risk. However, for teenagers, personal daily smoking increased the risk of fracture (RR = 1.43, 95% CI: 1.05, 1.95). The authors concluded that tall and heavy children had an increased risk of fracture, as did adolescents who smoked regularly.     

Maternal smoking and the risk of polyhydramnios.

BACKGROUND. Washington State birth certificates were used to conduct a population-based case-control study to assess the possible association of maternal smoking with polyhydramnios. METHODS. All singleton births complicated by polyhydramnios (n = 557) were identified from the vital records for the years 1984 to 1987. For comparison, 1671 records were randomly selected for the same years from singleton births uncomplicated by polyhydramnios. RESULTS. Women who reportedly smoked prenatally were found to be at increased risk for polyhydramnios (relative risk [RR] = 1.7, 95% confidence interval [CI] = 1.5-2.1, adjusted for marital status, maternal age, and parity). When women with conditions known to be associated with polyhydramnios were excluded, the risk for those who smoked prenatally remained elevated (RR = 1.8, 95% CI = 1.1-2.3). CONCLUSION. Overdistention of the uterus from polyhydramnios may cause a variety of pregnancy complications. The observed association of smoking with polyhydramnios may be a further indication for public health interventions aimed at preventing smoking during pregnancy.     

Risks of drug-related death, suicide, and homicide during the immediate post-release period among people released from New York City jails, 2001-2005

The authors assessed the risks of drug-related death, suicide, and homicide after release from New York City jails in 155,272 people who were incarcerated anytime from 2001 through 2005 and examined whether the mortality rate was associated with homelessness. Using jail records matched with death and single-adult homeless registries in New York City, they calculated standardized mortality ratios (SMRs) and relative risks. After adjustment for age, sex, race, and neighborhood, the risks of drug-related death and homicide in formerly incarcerated persons were 2 times higher than those of New York City residents who had not been incarcerated in New York City jails during the study period. These relative risks were greatly elevated during the first 2 weeks after release (for drug-related causes, SMR = 8.0, 95% confidence interval (CI): 5.2, 11.8; for homicide, SMR = 5.1, 95% CI: 3.2, 7.8). Formerly incarcerated people with histories of homelessness had higher rates of drug-related death (RR = 3.4, 95% CI: 2.1, 5.5) and suicide (RR = 2.1, 95% CI: 1.2, 3.4) than did persons without such histories. For individuals who died of drug-related causes, longer jail stays were associated with a shorter time until death after release. These results suggest that jail- and community-based interventions are needed to reduce the excess mortality risk among formerly incarcerated people.     

Association of a woman's own birth weight with her subsequent risk for pregnancy-induced hypertension

Studies have linked low birth weight to elevated risk for adult hypertension and insulin resistance. However, the relation between birth weight and later risk for pregnancy-induced hypertension (PIH), a disorder associated with insulin resistance and predictive of chronic hypertension, has not been well studied. This case-control study used linked hospital discharge and vital record data from New York State. Subjects were healthy women born in New York State who completed a first pregnancy there between 1994 and 1998. Records from each woman's own birth (1970-1985) were linked to those from her first pregnancy. Cases were 2,180 women diagnosed with PIH. Controls were the 22,955 remaining women with no record of PIH. Birth weight showed a U-shaped relation to risk for PIH, with the highest risks associated with very low and very high birth weights. Relative to women born at 3.5-4.0 kg, odds ratios adjusted for gestational age were 2.1 (95% confidence interval (CI): 1.1, 3.9) and 1.6 (95% CI: 1.1, 2.4), respectively, for women with birth weights less than 1.5 kg and greater than 4.5 kg. Adjustment for other perinatal factors reduced the association with high birth weight to 1.1 (95% CI: 0.7, 1.7) but strengthened that with lower birth weights, leaving a strong, inverse relation between birth weight and PIH risk (p for trend < 0.0001). These findings support a possible role for early life factors, particularly fetal growth, in the etiology of PIH.     

Maternal, delivery, and perinatal characteristics associated with cryptorchidism: a population-based case-control study among births in Washington State

BACKGROUND: The etiology of cryptorchidism is largely unknown. To identify maternal, perinatal, and delivery characteristics associated with cryptorchidism at birth, we conducted a population-based case-control study using Washington State birth certificates linked to birth hospitalization records. METHODS: We identified 2,395 cases of cryptorchidism among male infants born in Washington State during 1986-1996, and, for comparison, we randomly selected four controls per case (N = 9,580), frequency-matched by year of birth. RESULTS: Infant characteristics associated with cryptorchidism included low birth weight (OR = 1.5; 95% CI = 1.3-1.8), small size for gestational age (OR = 1.9; 95% CI = 1.6-2.2), and breech presentation (OR = 1.7; 95% CI = 1.4-2.1). In addition to cryptorchidism, cases were more likely to have another type of congenital malformation (OR = 3.7; 95% CI = 3.2-4.2), particularly digestive (OR = 6.8; 95% CI = 3.7-12.7) or genitourinary (OR = 4.1; 95% CI = 3.0-5.6). Maternal and pregnancy characteristics associated with cryptorchidism included nulliparity (OR = 1.2; 95% CI = 1.1-1.3), maternal smoking during pregnancy (OR = 1.2; 95% CI = 1.1-1.4), and the following pregnancy complications: oligohydramnios (OR = 1.8; 95% CI = 1.3-2.6), placental abnormality (OR = 1.3; 95% CI = 1.0-1.8), and pregnancy-induced hypertension (OR = 1.6; 95% CI = 1.4-1.9). Odds ratios were similar when the analysis was restricted to term infants. CONCLUSIONS: These findings suggest that factors affecting fetal growth and development may increase the risk of cryptorchidism.     

Maternal cigarette smoking and invasive meningococcal disease: a cohort study among young children in metropolitan Atlanta, 1989-1996

OBJECTIVES: This study assessed the association between maternal cigarette smoking during pregnancy and the risk of invasive meningococcal disease during early childhood. METHODS: Using a retrospective cohort study design, cases from an active surveillance project monitoring all invasive meningococcal disease in the metropolitan Atlanta area from 1989 to 1995 were merged with linked birth and death certificate data files. Children who had not died or acquired meningococcal disease were assumed to be alive and free of the illness. The Cox proportional hazards analysis was used to assess the independent association between maternal smoking and meningococcal disease. RESULTS: The crude rate of meningococcal disease was 5 times higher for children whose mothers smoked during pregnancy than for children whose mothers did not smoke (0.05% vs 0.01%). Multivariate analysis revealed that maternal smoking (risk ratio [RR] = 2.9; 95% confidence interval [CI] = 1.5, 5.7) and a mother's having fewer than 12 years of education (RR = 2.1; 95% CI = 1.0, 4.2) were independently associated with invasive meningococcal disease. CONCLUSIONS: Maternal smoking, a likely surrogate for tobacco smoke exposure following delivery, appears to be a modifiable risk factor for sporadic meningococcal disease in young children.     

A population-based cohort study of the relation between maternal birthweight and risk of gestational diabetes mellitus in four racial/ethnic groups

Intrauterine growth retardation and low birthweight have been associated with an increased risk of insulin resistance and type II diabetes later in life. We hypothesised that maternal low birthweight is associated with an increased risk of gestational diabetes mellitus (GDM). Study subjects comprised women giving birth in Washington State between 1987 and 1995. Information for 21,528 births to non-Hispanic white women, 6359 to African-American women, 7456 to Native American women and 6496 to Hispanic women was available for analysis. All information was derived from statewide computerised vital records and hospital discharge summaries of obstetric and neonatal admissions with linkage to birth certificates of mothers. Maternal birthweight was collected from subjects' birth certificates. Information from both the birth certificates and the obstetric and neonatal admissions database was used to determine whether subjects developed GDM. Poisson regression models were estimated to calculate unadjusted and adjusted risk ratios (RRs) and 95% confidence intervals (CIs) for GDM by categories of maternal birthweight. The cumulative incidence of GDM among non-Hispanic white, African-American, Native American and Hispanic women was 2.8, 2.6, 2.7 and 3.0% respectively. After adjusting for maternal age, parity, cigarette smoking, history of chronic hypertension and participation in the Medicaid programme, non-Hispanic white women with a birthweight < 2000 g were 1.7 times more likely to have had their pregnancy complicated by GDM (RR = 1.7; 95% CI 0.8, 3.3) than those with a birthweight 3000-3999 g. The corresponding adjusted RRs for African-American, Native American, and Hispanic women were 2.8 [95% CI 1.2, 6.1], 3.1 [95% CI 1.2, 8.2] and 2.4 [95% CI 0.9, 6.0] respectively. Among African-American women, those with a birthweight > or = 4000 g also experienced a twofold increased risk of GDM (RR = 2.1; 95% CI 1.0, 4.1). This association of high birthweight and increased GDM risk was not found among women in the other three racial/ethnic groups. These findings suggest that individuals with low birthweight constitute a group at increased risk for GDM.     

Congenital defects and electric bed heating in New York State: a register-based case-control study.

Exposure to 60-cycle electromagnetic fields has been hypothesized to be a cause of childhood cancer and congenital defects. Because electric bed heaters are a major source of variation in electromagnetic field exposure in the population, the authors conducted a case-control study in 1988-1989 to examine the relations between congenital defects and the use of electric blankets and heated waterbeds. Cases were identified by the New York State Congenital Malformations Registry as babies with cleft palate (n = 121), cleft lip with or without cleft palate (n = 197), born in 1983-1984, and anencephalus and spina bifida (n = 224), born in 1983-1986, all to upstate New York residents. Controls were selected at random from birth registrations individually matched to cases by maternal race, age, home county, month of last menses, and child's sex. Information on periconceptional electric blanket and heated waterbed use as well as known and suspected risk factors for defects was obtained from questionnaires mailed to the mothers. Matched odds ratio estimates and 95% confidence intervals (CIs) for electric blanket use relative to nonuse were 0.8 (95% CI 0.3-2.1) for cleft palate, 0.7 (95% CI 0.3-1.3) for cleft lip, and 0.9 (95% CI 0.5-1.6) for neural tube defects. The respective odds ratios for heated waterbed use were nearly identical to these. Adjustment for potential confounding factors (maternal education, vitamin use, smoking) and stratification by season of conception and bed heat control setting had no meaningful effect on odds ratios. These results suggest that 60-cycle fields do not cause neural tube and oral cleft defects.     

Determinants for non-use of contraception at first intercourse; a study of 10841 young Danish women from the general population

Based on interview data from 10841 Danish women aged 20 to 29 years, determinants for non-use of contraception at first intercourse (NU) were studied. One-fourth of the women (n = 2704) reported NU, whereas condoms and oral contraceptives were used by, respectively, 59% and 15%. NU decreased with the birth year of the first male partner (OR = 3.6; 95% CI: 2.8-4.8 for or=17 years) at the expense of both oral contraception and condom use. Finally, NU was found to predict high-risk sexual behavior in terms of subsequent multiple sex partners, non-use of condoms, and induced abortion.     

A cohort study of farming and risk of prostate cancer in Iowa.

Although farming has been linked to prostate cancer mortality, few investigations have addressed its association with prostate cancer incidence. We followed a population-based cohort of 1,177 cancer-free men for up to 9 years and identified 81 incident prostate cancers. Men whose usual occupation was farmer were at an increased risk of prostate cancer after adjustment for age, smoking, alcohol, and dietary factors (RR = 1.7; 95% CI = 1.0-2.7). Exclusion of well-differentiated, localized tumors slightly strengthened the association (RR = 2.0; 95% CI = 1.1-3.6). Risk was confined to older (age 70+ years) farmers (RR = 2.2; 95% CI = 1.1-4.3); we found no evidence of an effect among younger farmers (RR = 1.0; 95% CI = 0.4-2.1).     

Population-based study of small intestinal atresia and stenosis, Hawaii, 1986-2000

Atresia and stenosis are some of the most common birth defects affecting the small intestine. Few population-based studies have examined the epidemiology of small intestinal atresia/stenosis. Eighty-two cases of small intestinal atresia/stenosis were identified through a population-based birth defects registry in Hawaii during 1986-2000. The relationships of various clinical and demographic factors with small intestinal atresia/stenosis and duodenal atresia/stenosis were examined. The small intestinal atresia/stenosis and duodenal atresia/stenosis rates were 2.9 per 10,000 live births [95% confidence interval (CI) 2.3-3.6] and 1.3 per 10,000 live births (95% CI 1.0-1.9), respectively. No secular trend was observed (P = 0.067 and 0.090, respectively). Maternal age risk for small intestinal atresia/stenosis was U-shaped, while duodenal atresia/stenosis rates were highest with maternal age of 35 years or more. Small intestinal atresia/stenosis was substantially more common among Far East Asians than Caucasians [rate ratio (RR) 1.96, 95% CI 1.24-2.94]. Duodenal atresia/stenosis risk was higher in Hawaii County than in Honolulu County (RR 2.55, 95% CI 1.10-5.02). Small intestinal atresia/stenosis was also associated with low birth weight (RR 11.50, 95% CI 8.05-15.92), low gestational age (RR 8.60, 95% CI 6.34-11.41) and multiple births (RR 3.79, 95% CI 1.39-8.24). In conclusion, this study found associations between small intestinal atresia/stenosis and maternal age, maternal race/ethnicity, county of residence, birth weight, gestational age and plurality, but not delivery period. Many of the associations between small intestinal atresia/stenosis and other factors noted in this investigation were similar to those reported by other studies.     

Smoking and invasive cervical cancer risk. Results from a case-control study

The association between cigarette smoking and risk of invasive cervical cancer was investigated in a case-control study conducted in four hospitals in Leipzig, German Democratic Republic in 1983-1985. Analyses were based on 225 women aged 64 years or younger with newly diagnosed invasive cervical cancer and 435 age-matched controls with orthopedic or skin diseases. The crude relative risk of invasive cervical cancer was significantly elevated for women who had ever smoked (relative risk (RR) = 1.5, 95% confidence interval (CI) = 1.1-2.1). Adjustment for number of sexual partners reduced the risk to RR = 1.2 (95% CI = 0.8-1.6). Furthermore, the risk for smokers depended significantly on number of sexual partners (p less than 0.05) and was increased only among women with no partner or one partner (RR = 2.7, 95% CI = 1.2-6.1).     

Childhood brain tumor risk in relation to birth characteristics

A population-based case-control study was conducted utilizing linked cancer registry and birth certificate data to examine potential associations between selected birth characteristics and the occurrence of brain tumors in children. Cases (n = 157) were those children ages 10 and under who were born in Washington state and who were diagnosed with a primary brain tumor between 1974 and 1986. Controls were randomly selected from the Washington State birth files and were matched 5:1 to cases on year and county of birth. A limited number of positive findings emerged from the study. Results suggested that high birthweight may be related to an increased risk of childhood brain tumor (odds ratio (OR) = 1.4, 95% CI 1.0-2.0 for all histologies combined; OR = 1.9, 95% CI 1.1-3.1 for astrocytomas). The risk of astrocytoma was also observed to be associated with older maternal age (OR = 2.2, 95% CI 1.2-4.0) and a history of prior fetal death(s) (OR = 1.9, 95% CI 1.0-3.8).