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G G Rhoads

Publications and source records attributed to G G Rhoads.

At least 55 records · Page 3Linked to original sources
PubMed1995

A pilot study of take-home lead exposure in New Jersey.

Studies in various industries have found an association between worker exposure to lead and elevated blood lead levels in workers' children, but the magnitude of this problem is unknown. In an effort to characterize this problem further, a pilot study was undertaken to obtain blood lead levels of children of lead-exposed workers with elevated blood lead levels who had been reported by laboratories to the New Jersey Department of Health. Fifteen workers' families participated in this study, including 28 children. Thirty-two percent of the children were found to have blood lead levels > or = 10 micrograms/dl, the level of concern set by the Centers for Disease Control and Prevention for medical monitoring. This finding is in contrast to population-based data collected from the Third National Health and Nutrition Survey, where the overall prevalence of blood lead levels > or = 10 micrograms/dl was only 4.5%.

Adolescent↗
PubMed1995

Lead in house dust: relationships between exposure metrics.

This paper examines the quantitative relationships between dust loading, lead loading, and lead concentration in house dust. Bare floor, interior sill, and carpet dust samples were collected in 216 Jersey City, New Jersey, homes using quantitative wipe and vacuum sampling techniques. Comparison of wipe and vacuum sample distributions for these homes indicated that lead loading was more variable than dust loading or lead concentration measured on floors, sills, or carpets. These data also indicated that increased lead loading on carpets relative to sills or floors was due to higher dust loading on carpets. Correlation analysis of wipe samples indicated that dust loading was more strongly correlated with lead loading on floors (r = 0.73) than on sills (r = 0.53), that dust loading was not correlated with lead concentration on either surface, and that lead loading and lead concentration were more strongly correlated in samples collected from sills (r = 0.81) than from floors (r = 0.65). Most importantly, carpets and rugs served as large reservoirs for house dust and consequently were a large potential source of dust exposure in children's common microenvironments.

Air Pollutants↗
PubMed1994

Are obese women at higher risk for producing malformed offspring?

OBJECTIVE: Our purpose was to determine whether obese women and underweight women have an increased risk of birth defects in their offspring. STUDY DESIGN: A geographically based case-control study of women living in California and Illinois was performed. There were 499 mothers of offspring with neural tube defects, 337 mothers of offspring with other major birth defects, and 534 mothers of offspring without birth defects who participated. RESULTS: Compared with women of normal weight, women who were extremely obese before pregnancy (body mass index > or = 31 kg/m2) showed a significantly increased risk of having an infant with a neural tube defect (odds ratio 1.8, 95% confidence interval 1.1 to 3.0), especially spina bifida (odds ratio 2.6, 95% confidence interval 1.5 to 4.5), after adjustments for age, race, education, and family income. Obese women also had significantly increased risks (p < 0.05) of having an infant with other defects of the central nervous system, great vessel defects, ventral wall defects, or other intestinal defects. CONCLUSION: Our data suggest that offspring of obese women (but not underweight women) are at an increased risk of neural tube defects and several other malformations. If these findings are confirmed, further research will be necessary before it can be concluded that weight reduction before pregnancy will lower the risk of birth defects among obese women. Until then, obese women can address their risk of birth defects with the same measures that are recommended for all women, such as adequate daily intake of folic acid and alpha-fetoprotein screening to identify malformed fetuses.

Adult↗
PubMed1992

Maternal vitamin levels during pregnancies producing infants with neural tube defects.

Women at very high risk for having a child with a neural tube defect (NTD) because they had previously delivered affected children significantly reduced their recurrence rate by taking folate supplements before conception. To clarify how these results might apply to a lower-risk general obstetric population, we measured folate, vitamin B12, and retinol levels in maternal serum drawn early in 89 pregnancies resulting in NTD offspring and 178 control pregnancies identified from the Finnish Registry of Congenital Malformations. In 86.5% of the subjects, specimens were collected within 8 weeks after neural tube closure. In the NTD case mothers the mean (+/- SD) levels were not significantly lower than in control mothers: folate, 4.13 +/- 2.36 versus 4.28 +/- 2.52 ng/ml; vitamin B12, 482.8 +/- 161.1 versus 520.3 +/- 191.9 pg/ml; and retinol, 51.2 +/- 17.0 versus 50.5 +/- 16.9 micrograms/dl. After adjustment for age of the specimen, gestational age at which the specimen was drawn, maternal age, and maternal employment status, the odds ratios for being a case mother were 1.00 (95% confidence interval (CI) 0.91 to 1.10) for folate, 1.05 (95% CI 0.92 to 1.19) for vitamin B12, and 0.99 (95% CI 0.88 to 1.10) for retinol. Excluding NTD cases with known or suspected causes unrelated to vitamins, restricting the analyses to interviewed subjects, and excluding subjects whose specimens were collected after 15 gestational weeks confirmed that NTD case and control vitamin levels did not differ significantly. This population-based investigation in a low rate area demonstrated no relationship between maternal serum folate, vitamin B12, or retinol levels during pregnancy and the risk of NTDs.

Adult↗
PubMed1991

Spontaneous and induced abortion among resident physicians.

Female resident physicians are believed to be at an increased risk for a variety of third-trimester pregnancy complications. However, early pregnancy complications have been less well studied. This report compares spontaneous and induced abortions in a nationally representative sample of 5096 female medical school graduates (who experienced 1284 pregnancies) and of the sexual partners of 5000 of their male classmates (who experienced 1481 pregnancies). The response to the survey was 86.1%. The life-table probability of spontaneous abortion was 14.8% for female residents compared with 12.6% for the sexual partners of male residents. However, female residents were more likely than the male residents' sexual partners to terminate a pregnancy voluntarily (8.2% vs 2.7%). The increased risk of voluntary termination persisted when only married women were studied (3.6% vs 1.4%). However, female residents' pregnancies were at approximately half the risk of voluntary termination compared with pregnancies among the general US population of women aged 25 to 34 years. These results provide reassurance to those residents who would like to become pregnant but are concerned about the possible effect of their occupation on the course of the pregnancy.

Abortion, Induced↗
PubMed1991

Vitamins, folic acid and neural tube defects: comments on investigations in the United States.

No clear answer concerning whether multivitamin/folate supplementation prevents neural tube defects (NTDs) is provided by three studies in the United States. All these studies are occurrence in nature, no recurrence studies having been conducted. The Atlanta Birth Defects Study is subject to pronounced memory and recall biases, the length between event and interview being as long as 16 years. In a second study (Boston University), objections can be raised to certain aspects of the experimental design, and the claim that 22 per cent of women started vitamins sufficiently early after pregnancy diagnosis to influence NTD formation is suspicious. Our NICHD case control study of 541 women in California and Illinois revealed no evidence for multivitamins or folic acid preventing NTDs. U.S. public policy-makers face difficulties in applying results of recurrence or occurrence studies in high-risk areas to low-risk areas in the U.S.

Female↗
PubMed1991

Home monitoring of uterine contractility. Summary of a workshop sponsored by the National Institute of Child Health and Human Development and the Bureau of Maternal and Child Health and Resources Development, Bethesda, Maryland, March 29 and 30, 1989.

At an interdisciplinary workshop on home monitoring of uterine activity, participants reviewed the basis of this technology and its use in the identification of women at high risk of preterm delivery and in the prevention of preterm birth. Although the guard-ring devices in current use appear capable of detecting uterine activity, they do not clearly distinguish between Braxton Hicks contractions and the contractions of early labor. There was agreement that women destined for preterm delivery have more uterine activity on average than do other women of comparable gestational age but that there is substantial overlap between the two groups. Thus it is uncertain whether this difference can be used effectively for screening purposes. Conferees agreed that there is considerable evidence that twice-daily monitoring of very-high-risk women, in conjunction with daily nursing support and high-quality obstetric care, may prevent preterm births. Available evidence does not clearly distinguish the contribution of tocodynamometry from that of nursing support. A number of areas were identified in which further research is needed.

Cardiotocography↗
PubMed1991

A review of some tumors of interest for demographic study in Hawaii.1974.

Because of its multiracial character, Hawaii presents a unique opportunity to carry out demographic investigations of the etiology of certain common cancers. Tumors with substantially different incidence rates among the major ethnic groups in the Islands, or between a given immigrant group and its country of origin, are of particular interest for such studies. Among the cancer sites meeting these criteria, nasopharynx, stomach, prostate, large bowel, liver, female breast, uterine corpus, ovary, bladder, and thyroid are particularly prominent.

Ethnicity↗
PubMed1991

Genetic heterogeneity in neural tube defects.

In 1985-1987, the authors attempted to ascertain all cases of confirmed neural tube defects (NTD) in California and Illinois, not only among live-born infants (postnatal) but also cases ascertained during pregnancy (prenatal). Mothers of both prenatal and postnatal NTD cases were interviewed within 5 months. Among postnatal NTD cases, 14.9% (45/303) had anomalies not ordinarily associated with NTD. The frequency of non-NTD related anomalies was 9.4% (5/53) in anencephaly, 0/3 in craniorachischisis, 22.9% (8/35) in encephalocele, 14.5% (27/186) in spina bifida, 20% (1/5) in multiple NTD cases and 19% (4/21) in other NTDs. However, relatively few postnatal NTD cases had known multiple malformation patterns; Meckel-Gruber syndrome was the most common, with 2 postnatal cases, and 3 additional prenatal cases. Maternal age, paternal age and birth order in postnatal cases were 26.7 +/- 5.4 SD, 28.9 +/- 5.8 and 2.8 +/- 1.8, respectively. These characteristics were similar in prenatal NTD cases (27.9 +/- 6.0, 30.1 +/- 6.3, 2.5 +/- 1.5, respectively). We also found no differences in parental ages among different types of NTD. Frequency of prior spontaneous abortion differed neither between postnatal NTD (9.3%) and postnatal controls (8.1%), nor between prenatal NTD (10.7%) and prenatal control (8.7%). Loss rates in the pregnancy immediately prior to the index NTD cases were not significantly higher than in control subjects. The high frequency of non-NTD associated malformations (14.9%) indicates the caution must be exercised before assuming that a given NTD case is polygenic-multifactorial in etiology, especially cases of encephalocele.

Abnormalities, Multiple↗
PubMed1991

Hypochloremic metabolic alkalosis from ingestion of a chloride-deficient infant formula: outcome 9 and 10 years later.

In 1978 and 1979 two infant formulas, Neo-Mull-Soy and Cho-Free, were found to be deficient in chloride. The Centers for Disease Control received reports that hypochloremic metabolic alkalosis (HMA) had developed in 141 children as a result of exposure to these formulas. Thirty-five of these children were examined at 9 and 10 years of age and compared with a group of 32 children who were exposed to the chloride-deficient formulas but were not reported to experience HMA and a group of 61 children who received chloride-sufficient soy formulas in infancy. The control children were matched to the HMA children on sex, race, age, and maternal education. Growth characteristics, performance on the Wechsler Intelligence Scale for Children-Revised (WISC-R), the Boston Naming Test, the Rey-Osterrieth Test, the Clinical Evaluation of Language Fundamentals-Revised (CELF-R), and subtests from several other speech and language tests were compared across the groups. After adjustment for family income and the level of the father's education, significantly lower scores were observed in the HMA children on the WISC-R Arithmetic subtest (mean = 10.5) compared with the soy control children (mean = 12.0, P less than .05) and on the WISC-R Coding subtest (mean = 9.0) compared with the soy control children (mean = 10.8, P less than .01). All the WISC-R subtest scores were, however, within the normal range. Although no significant differences occurred on the CELF-R between groups, the risk of an HMA child falling below the range expected for a standard population was increased on the CELF-R Composite Total, Receptive, and Expressive Language scores: risk ratios = 2.14, 2.14, and 3.03 respectively. Significant differences were observed between the children exposed, both HMA and non-HMA children, and the soy control children for behavioral problems as determined by the Achenbach Childhood Behavioral Checklist. It is concluded that as a group, children with documented HMA appear to have recovered from their growth failure and have normal cognitive development. They may, however, be at risk for deficits in language skills that require expressive language abilities.

Alkalosis↗
PubMed1990

Outcomes of pregnancy in a national sample of resident physicians.

BACKGROUND: Physically demanding, highly stressful work during pregnancy has been reported to cause a variety of adverse outcomes. It has been difficult, however, to separate the effects of work from those of socioeconomic status. METHODS: By means of a national questionnaire-based survey, we studied the outcomes of pregnancy during residency for 4412 women who graduated from medical school in 1985 and for the wives of 4236 of their male classmates, who served as controls. RESULTS: The rate of response to our survey was 87 percent (4412 of 5079) for the women residents and 85 percent (4236 of 4968) for the wives of the male residents. There were no significant differences in the proportion of pregnancies ending in miscarriage (13.8 percent for residents vs. 11.8 percent for their classmates' wives, P = 0.12), ectopic gestations (0.5 percent vs. 0.8 percent, P = 0.69), and stillbirths (0.2 percent vs. 0.5 percent, P = 0.20). There were 989 women residents and 1238 residents' wives whose first pregnancy during residency resulted in the live birth of a singleton infant. Although during each trimester the women residents worked many more hours than the wives of the male residents, the frequency of preterm births (less than 37 weeks' gestation) was similar: 6.5 percent for residents and 6.0 percent for residents' wives (odds ratio = 1.1; 95 percent confidence interval, 0.7 to 1.5). Infants who were small for gestational age (with birth weights less than the 10th percentile for gestational age) were born to 5.3 percent of the residents and 5.8 percent of the residents' wives (odds ratio = 0.9; 95 percent confidence interval, 0.6 to 1.3). Adjustment for factors that differed between the women residents and the wives of male residents resulted in odds ratios of 1.2 (95 percent confidence interval, 0.8 to 1.7) for preterm delivery and 0.9 (95 percent confidence interval, 0.6 to 1.3) for the delivery of an infant who was small for gestational age. However, the women residents more frequently reported having had preterm labor (11 percent vs. 6 percent), but not preterm delivery (6.5 percent vs. 6.0 percent); preeclampsia was also more common among the women residents (8.8 percent vs. 3.5 percent). CONCLUSIONS: These results suggest that working long hours in a stressful occupation has little effect on the outcome of pregnancy in an otherwise healthy population of high socioeconomic status.

Abortion, Spontaneous↗
PubMed1990

Risk of neural tube defects in relation to maternal fertility and fertility drug use.

In a case-control study to investigate whether women who use drugs to induce ovulation are at increased risk of conception of a child with a neural tube defect, 571 women who had a fetus or child with a neural tube defect, 546 women who had a fetus or child with other abnormalities, and 573 women who had an apparently normal fetus or child were questioned about infertility, fertility drug use, and related obstetric problems. The rate of maternal fertility drug use around the time of conception was not significantly higher for neural tube defects than for other abnormalities (odds ratio 1.28; 95% confidence interval 0.39, 4.51) or no abnormalities (odds ratio 0.80; 95% Cl 0.27, 2.27). Fertility drug use at any time was not significantly more frequent for neural tube defects than for other abnormalities (odds ratio 1.37; 95% Cl 0.70, 2.74) or no abnormalities (odds ratio 1.05; 95% Cl 0.56, 1.98).

Abnormalities, Drug-Induced↗
PubMed1989

Increasing cesarean section rates in very low-birth weight infants. Effect on outcome.

Examination of a linked birth and death certificate file from Missouri revealed a remarkable increase in the use of cesarean section for very low-birth weight infants (500 to 1499 g) from 24% to 44% in the years 1980 to 1984. In the same years the rate for 1500- to 2499-g infants went from 21% to 26% and the rate for 2500- to 7000-g infants went from 14% to 18%. We studied first-day death rates in very low-birth weight infants as an indicator of potential benefit from this increase in cesarean sections. During the 5-year period first-day deaths averaged 10% and 22% in the cesarean and vaginal birth groups, respectively. This difference was explained almost entirely by deaths in the 500- to 740-g birth weight group, where the death rates were 33% and 59%, respectively. Although this difference remained statistically significant after adjustment for gestational age and other factors that differed between the groups, it was nullified by an excess of deaths in the succeeding 6 days of life. Overall, the odds of death in the first week in these infants weighing 500 to 749 g was 0.85 (95% confidence interval, 0.52 to 1.39) in the cesarean vs vaginal deliveries. We conclude that there is little evidence that the use of cesarean section for the delivery of very low-birth weight infants, independent of maternal or fetal compromise, improves overall survival. We were unable to find reasons to justify the sharp increase in the use of cesarean sections for these small infants.

Cesarean Section↗
PubMed1989

The absence of a relation between the periconceptional use of vitamins and neural-tube defects. National Institute of Child Health and Human Development Neural Tube Defects Study Group.

Whether taking multivitamins or folate around the time of conception can reduce a woman's risk of having a child with a neural-tube defect is controversial. To investigate this question, we examined the periconceptional use of vitamin supplements by women who had a conceptus with a neural-tube defect (n = 571), women who had had a stillbirth or a conceptus with another malformation (n = 546), and women who had had a normal conceptus (n = 573). Women with conceptuses with neural-tube defects were identified either prenatally or postnatally and were matched to control mothers for gestational age. To minimize recall bias, we interviewed nearly all the women within five months of the diagnosis of a birth defect or the birth of the infant (mean, 84 days); information on vitamin use was obtained by an interviewer who was unaware of the outcome of pregnancy. The rate of periconceptional multivitamin use among the mothers of infants with neural-tube defects (15.8 percent) was not significantly different from the rate among mothers in either the abnormal or the normal control group (14.1 percent and 15.9 percent, respectively). After adjustment for potential confounding factors, the odds ratio for having an infant with a neural-tube defect among women classified as having had full supplementation with multivitamins was 0.95 as compared with the mothers of the abnormal infants (95 percent confidence interval, 0.78 to 1.14) and 1.00 as compared with the mothers of normal infants (95 percent confidence interval, 0.83 to 1.20). There were no differences among the groups in the use of folate supplements. The adjusted odds ratio for having an infant with a neural-tube defect among those receiving the recommended daily allowance of folate was 0.97 as compared with the mothers of abnormal infants (95 percent confidence interval, 0.79 to 1.18) and 0.98 as compared with the mothers of normal infants (95 percent confidence interval, 0.80 to 1.20). We conclude that the periconceptional use of multivitamins or folate-containing supplements by American women does not decrease the risk of having an infant with a neural-tube defect.

Adult↗
PubMed1989

Facts and artifacts about anemia and preterm delivery.

The effect of anemia (hematocrit less than or equal to 0.34) on subsequent preterm birth was prospectively studied in 35,423 pregnancies. The incidence of preterm birth among women with and without anemia at each week during the third trimester was compared. Early in the third trimester, there was a weak association between anemia and preterm delivery. However, anemia early in the third trimester did not account for the substantial increase in preterm birth seen among black women. Anemia after 30 weeks' gestation was not associated with preterm birth. Among women delivering term infants weighing 2500 g or more, the mean hematocrit rose 0.029 among black women and 0.021 among white women from 25 weeks to term. Compared with hematocrits at 40 weeks' gestation, the odds ratios for anemia reached a maximum at 28 weeks and fell sharply as term approached. When the hematocrits of women in term labor were compared with those of women in preterm labor, a spurious dose-response effect for anemia was created. We conclude that anemia is not a strong factor in the pathogenesis of preterm birth and that comparison of hematocrits from women who are in preterm and term labor produces biased results.

Anemia↗
PubMed1989

The safety and efficacy of chorionic villus sampling for early prenatal diagnosis of cytogenetic abnormalities.

Chorionic villus sampling is a method of prenatal diagnosis in the first trimester of pregnancy in which tissue for genetic study is aspirated from the developing placenta by means of a catheter inserted transcervically under the guidance of ultrasonography. In this seven-center study, we compared the safety and efficacy of chorionic villus sampling in 2278 women with those of amniocentesis at 16 weeks' gestation in 671 women. Both groups were made up primarily of well-educated private patients; they were recruited in the first trimester of pregnancy and had viable pregnancies verified by ultrasound examination. Cytogenetic diagnoses resulted from 97.8 percent of the chorionic villus sampling procedures and 99.4 percent of the amniocenteses (P less than 0.05); aneuploidy was found in 1.8 and 1.4 percent, respectively, of the cases in which diagnoses were made. Of the women who underwent chorionic villus sampling, 17 (0.8 percent) subsequently had an amniocentesis because the diagnosis was ambiguous. Two of the diagnoses of aneuploidy (one tetraploidy, one trisomy 22) were later proved to be incorrect. On the basis of pediatric examination of the infants subsequently born to the women in the sample, there were no errors in the determination of sex or the identification of the major trisomies (21, 18, and 13). The rate of combined losses due to spontaneous and missed abortions, termination of abnormal pregnancies, stillbirths, and neonatal deaths was 7.2 percent in the group that underwent chorionic villus sampling and 5.7 percent in the group that had amniocentesis. After adjustment for slight differences in gestational and maternal age, the total loss rate for the women in the chorionic villus sampling group exceeded that for the amniocentesis group by only 0.8 percentage points (80 percent confidence interval, -0.6 to 2.2). The rate of loss of chromosomally normal fetuses after chorionic villus sampling was 10.8 percent among women in whom three or four attempts were made to place the transcervical catheter, as compared with 2.9 percent in those in whom only one attempt was necessary (P less than 0.01). There were no serious maternal infections among the women in this study or among an additional 1990 women who underwent chorionic villus sampling (upper 95 percent confidence limit, 0.08 percent). We conclude that chorionic villus sampling is a safe and effective technique for the early prenatal diagnosis of cytogenetic abnormalities, but that it probably entails a slightly higher risk of procedure failure and of fetal loss than does amniocentesis.

Abortion, Spontaneous↗