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Biomedical subjects

M L Hediger

Publications and source records attributed to M L Hediger.

At least 37 records · Page 2Linked to original sources
PubMed1996

Dietary and serum folate: their influence on the outcome of pregnancy.

We examined the influence of folate intake from diet and supplements b y 28 wk of gestation and third trimester circulating concentrations of serum folate on the outcome of pregnancy in women from Camden, NJ. Mean daily folate intake by week 28 included both dietary and supplemental folate obtained prospectively in 832 women. Circulating concentrations of serum folate as well as serum vitamin B-12 were assayed at 28 wk of gestation (+/- 2 wk) by radioimmunoassay. The outcomes of interest included preterm delivery (<37 wk) and infants with low birth weight (<2500 g). Mean folate intake was significantly correlated with circulating concentrations of serum folate (r=0.17, P<0.001). Women with a low mean daily folate intake (</-240 microgram/d) had an approximately twofold greater risk of preterm delivery and infant low birth weight after maternal characteristics, energy intake, and other correlated nutrients were controlled for. Lower concentrations of serum folate at week 28 were also associated with a greater risk of preterm delivery and low birth weight.

Adolescent↗
PubMed1995

Maternal serum uric acid levels in twin gestations.

OBJECTIVE: To establish normative values of serum uric acid levels in women with twin gestations and to compare maternal serum uric acid levels of twins and singletons, stratified by the presence or absence of preeclampsia. METHODS: Sixty-seven normotensive and 16 preeclamptic women with twin gestations, who had no underlying chronic hypertension or renal insufficiency, had serum uric acid levels measured on admission to the labor and delivery unit. These levels were compared with those of 83 normotensive and 10 preeclamptic singleton gravidas admitted to the same unit. A receiver operating characteristic (ROC) curve was used to determine the optimal maternal serum uric acid cutoff value for twin gestations and to compare this value with that of singleton gestations. RESULTS: Women with non-preeclamptic twin pregnancies had significantly higher mean (+/- standard deviation) serum uric acid concentration than women with non-preeclamptic singleton pregnancies (5.4 +/- 1.6 versus 4.7 +/- 1.2 mg/dL, respectively, P = .001). Gravidas with twin gestations complicated by preeclampsia had significantly higher serum uric acid levels than their preeclamptic singleton counterparts (7.7 +/- 1.3 versus 5.9 +/- 1.1 mg/dL, respectively, P = .001). Using a ROC curve, we determined that a maternal serum uric acid level of 6.5 mg/dL appeared to be the optimal cutoff for identifying preeclampsia in twin gestations, with a sensitivity of 94% and specificity of 78%. CONCLUSION: With or without preeclampsia, women carrying twins have significantly higher serum uric acid levels than their singleton counterparts, which suggests a need for separate normative values for twin gestations. We propose that a serum uric acid level of 6.5 mg/dL or greater be used to identify those women with twin gestations who are at higher risk for preeclampsia.

Adolescent↗
PubMed1995

Fetal growth and the etiology of preterm delivery.

OBJECTIVE: To confirm that preterm delivery is associated with fetal growth restriction (FGR), and to determine if the various etiologies of preterm delivery are associated with the same degree and type of FGR. METHODS: Two hundred ninety young, primarily minority gravidas who had routine initial ultrasound examinations also had subsequent ultrasound examinations at 32 weeks' gestation. Fetal growth characteristics were compared between preterm (less than 37 weeks' gestation) and term deliveries, and among preterm deliveries with medical or obstetric indications, premature rupture of membranes (PROM), and spontaneous preterm labor. RESULTS: Forty-six infants (15.9%) were born preterm. At 32 weeks' gestation, all fetuses later delivered preterm were already smaller than fetuses later delivered at term (P < .05) for all dimensions: head circumference (HC), abdominal circumference (AC), biparietal diameter (BPD), and femur length (FL). However, after stratifying by cause of preterm delivery for those fetuses later delivered for medical or obstetric indications, we found that only AC was decreased (P < .01) and that the HC-AC ratio was elevated (asymmetric FGR). Neonates delivered after unsuccessfully treated PROM or preterm labor were symmetrically smaller in all characteristics (HC, AC, BPD, and FL). CONCLUSION: By 32 weeks' gestation, fetuses later delivered preterm are already significantly smaller than fetuses later delivered at term. However, when stratified by the etiology of preterm delivery, infants delivered preterm for medical or obstetric indications had asymmetric growth patterns, which suggests a growth failure late in pregnancy. Infants delivered preterm after PROM or after failed or no tocolysis for spontaneous preterm labor were proportionately smaller, implying an overall slowing of growth that may originate early in pregnancy and possibly demonstrate a more chronic stress.

Adult↗
PubMed1995

Gestational weight gain, pregnancy outcome, and postpartum weight retention.

OBJECTIVE: To determine whether the risk of maternal overweight associated with an excessive rate of gestational gain needs to be balanced against the risks of impaired fetal growth associated with a low rate of gain. METHODS: Rate of gestational weight gain was measured prospectively in a sample of 274 young, low-income, and primarily minority women (12-29 years old) with pregravid body mass indices (BMI) in the normal range (19.8-26.0). We defined an excessive rate of gain between 20-36 weeks' gestation as one greater than 0.68 kg/week, and a low rate of gain as one less than 0.34 kg/week. Women were followed-up at 4-6 weeks and 6 months postpartum. RESULTS: Rate of measured gestational gain between 20-36 weeks' gestation was associated with total weight gain based on pregravid weight, with infant birth weight and gestation duration, and with maternal overweight (BMI greater than 26) and weight retention postpartum. Infant birth weight and gestation duration were significantly reduced for women with low rates of gain, and there was no significant difference between women with excessive and moderate gains. Despite little difference in pregravid BMI, women with excessive rates of gain retained more weight overall, attained a greater postpartum BMI, and had higher levels of subcutaneous fat and overweight. Maternal anthropometric status showed little change between 4-6 weeks and 6 months postpartum. CONCLUSION: Weight gained at an excessive rate by women with a pregravid BMI in the normal range does not greatly enhance fetal growth and gestation duration, contributing instead to postpartum maternal overweight.

Adolescent↗
PubMed1995

One-year changes in weight and fatness in girls during late adolescence.

OBJECTIVE: To document postmenarcheal growth and changes in weight and fatness in girls. DESIGN: Mixed longitudinal study to determine yearly growth increments. PARTICIPANTS: Six hundred sixty-eight postmenarcheal girls, initially ages 13 to 17 years, from two Philadelphia high schools. Overall, 61.4% of the girls were white, 15.7% black, 16.8% Puerto Rican Hispanic, and 6.1% of other ethnicities (non-Puerto Rican Hispanic or Asian). OUTCOME MEASURES: Height (in centimeters), weight (in kilograms), and triceps and subscapular skinfold thicknesses (in millimeters) were measured initially and after 1 year. The anthropometric measures were analyzed both cross-sectionally by age cohort and longitudinally. RESULTS: Viewed cross-sectionally by chronologic age groups and adjusted for ethnicity, gynecologic age, cigarette smoking, and late maturation (menarche > or = 14 years), there were no statistically significant trends with age in height, weight, body mass index (kilograms per m2), triceps, or subscapular skinfold thicknesses. Nevertheless, there were significant trends in velocity with increasing chronologic age. On the average, postmenarcheal girls gained about 6.5 kg (14.3 lb) during late adolescence from about 1.5 years after menarche to age 18 years. Height and triceps skinfolds showed significantly decreasing velocities, whereas there was a significant monotonic increase in velocity with age for skinfolds at the subscapular site. CONCLUSIONS: Even with normal weight gain during late adolescence in girls, there seems to be greater potential for fat deposition centrally. Thus, excessive weight gain during late adolescence may exacerbate the normal processes of fat deposition, leading to large gains in central fat, and thereby increasing the long-term risk for metabolic and cardiovascular diseases later in life.

Adipose Tissue↗
PubMed1994

Effect of high-sugar intake by low-income pregnant adolescents on infant birth weight.

PURPOSE: The objective of this study was to determine the effect of total sugar intake by pregnant adolescents from low-income families on infant birth weight and small-for-gestational-age (SGA) infants. METHODS: The study sample consisted of 337 adolescents, enrolled in a county-wide demonstration project in Camden, New Jersey, who delivered live, singleton newborns. The adolescents were divided into two groups at the 90th percentile for the study sample total sugar intake (206 g): high-sugar intake (> or = 206 g, n = 34) and low-sugar intake group (< 206 g, n = 303). RESULTS: The sample was 46% black, 30% white, and 24% Hispanic. The sample gestational age and birth weight (mean +/- SD) were 39 +/- 3 weeks and 3189 +/- 666 g, respectively. After adjusting for energy intake, the high- compared with the low-sugar intake group was more likely to consume higher total sugar and carbohydrate but lower protein and fat. Likewise, the high-compared to the low-sugar intake group consumed significantly more calcium and magnesium. After adjusting for possible confounding variables such as maternal age, ethnicity, marital status, parity, smoking, net weight gain, body mass index, energy intake, and gestational age at birth, adolescents on high- compared to low-sugar diets gave birth to infants weighing 215 +/- 104 g less (p = 0.04). The adjusted odds ratios were 3.41 (95% confidence interval, 1.14 to 10.23) for delivering a SGA infant among adolescents with high- compared with low-sugar intakes. CONCLUSIONS: Low-income adolescents consuming high-sugar diets are at increased risk for delivering lower birth weight and SGA infants.

Adolescent↗
PubMed1994

Prenatal care and maternal health during adolescent pregnancy: a review and meta-analysis.

PURPOSE: A meta-analysis and review of pregnancy complications and behavioral risk factors associated with infant low birth weight and other poor outcomes which occur during adolescent pregnancy was undertaken using the published literature. METHODS: Studies were eligible for inclusion if they: 1) utilized a clearly defined sample of teenagers 2) provided numeric data on complications of interest or the proportions needed to compute this information 3) included a control or comparison group. RESULTS: Many behavioral risk factors (smoking, drinking and drug use) appeared to be less prevalent among teenage gravidas, particularly when the young women were ethnic minorities. An increased risk of preterm delivery was associated with young maternal age in both developed and developing countries. In the developed world, risk of cesarean delivery was reduced for teenagers and there was a secular decline in maternal anemia and pregnancy induced hypertension in comparison to the risk sustained by more mature women. Programs of comprehensive prenatal care appeared to have the potential to diminish risk of many complications. In the developing world, teenagers were at increased risk of maternal anemia, preterm birth and cesarean delivery. CONCLUSIONS: Although future research efforts will need to address the issues of bias inherent in much of the published research, the published literature suggests that prenatal care regimens which provide social and behavioral services along with medical care could improve both the health of the mother and the outcome of her pregnancy.

Adolescent↗
PubMed1994

Anemia and iron-deficiency anemia: compilation of data on pregnancy outcome.

Anemia diagnosed early in pregnancy is associated with increased risks of low birth weight and preterm delivery. In several studies, the association between anemia and outcomes reversed direction during the third trimester; maternal anemia was no longer a risk factor for poor pregnancy outcomes. Camden study data were used to examine the probable cause of this observation. Maternal iron-deficiency anemia, diagnosed at entry to prenatal care, was associated with low dietary energy and iron, inadequate gestational gain, and twofold or greater increases in the risks of preterm delivery and low birth weight. During the third trimester, these associations (except with inadequate gestational gain) were no longer present. This reversal of risk status may be attributable to the poor predictive value of anemia and iron deficiency tests during the third trimester. However, the relationship between poor diet (with inadequate iron intake) and increased likelihood of preterm delivery persisted during the third trimester.

Anemia, Hypochromic↗
PubMed1994

Maternal growth during pregnancy and the competition for nutrients.

The influence of maternal growth in knee height during pregnancy on birth weight, gestation, and maternal body composition was examined in 318 teenagers (144 growing, 174 nongrowing) and 276 mature women from the Camden Study. Body-composition differences associated with maternal growth did not arise until after 28 wk gestation, when growing gravidas continued to accrue fat, had larger gestational gains, and retained more of their gestational weight gain postpartum. Nevertheless, still-growing young mothers had infants with lower birth weight, particularly when the mother continued to accrue higher amounts of fat on the arm or back (subscapular site) late in gestation. Thus, despite an apparently sufficient weight gain and the accumulation of abundant stores during pregnancy, young still-growing women appeared not to mobilize fat reserves late in pregnancy to enhance fetal growth, apparently reserving them instead for their own continued development.

Adipose Tissue↗
PubMed1994

Changes in maternal upper arm fat stores are predictors of variation in infant birth weight.

The relationship between changes in maternal subcutaneous fat and infant birth weight was studied in 608 low income women. A loss of upper arm fat area (> 6.4 cm2), measured from 28 wk gestation to 4-6 wk postpartum, was associated with greater birth weight (+144 g, P < 0.01). However, when pregravid weight was low (< 25th percentile for age), a loss of upper arm fat area was associated with a birth weight lower by more than 300 g than that for women with higher pregravid weights who also lost fat, indicating that maternal stores among those with low weight may have been relatively depleted. Continued gains in upper arm fat area (> 5 cm2) from 28 wk gestation to the postpartum period was also associated with a lower birth weight (-123 g, P < 0.02). The mothers who gained upper arm fat late in pregnancy or continued to accrue fat in the postpartum period had the largest gestational weight gains, bore infants who were smaller, and retained the most weight postpartum. Thus, change in upper arm fat is a significant predictor of variation in infant birth weight.

Adipose Tissue↗
PubMed1993

Low zinc intake during pregnancy: its association with preterm and very preterm delivery.

Zinc affects growth, development, and reproduction. However, the effect of poor maternal zinc nutriture, usually measured as plasma zinc, on poor pregnancy outcome has not been consistent. The influence of dietary zinc on pregnancy outcome was examined in a cohort of 818 pregnant girls and women from a poor urban community in Camden, New Jersey (1985-1990). Zinc intake in this sample was 11.1 mg/day, a level ascertained from averaged 24-hour dietary recalls during pregnancy. Gravidas with low zinc intake (< or = 6 mg/day, amounting to 40% of the recommended dietary allowance for pregnancy) had lower caloric intake and multivitamin usage as well as a higher incidence of inadequate weight gain during pregnancy and iron deficiency anemia at entry to prenatal care compared with those with higher intakes. A low zinc intake was associated with approximately a twofold increase in the risk of low birth weight (< 2,500 g) after controlling for calories and other confounding variables. The risk of preterm delivery (< 37 completed weeks) was also increased, particularly when rupture of the membranes preceded the onset of labor (adjusted odds ratio = 3.46, 95% confidence interval 1.04-11.47). A low intake of dietary zinc earlier in pregnancy was associated with a greater than threefold increase in the risk of very preterm delivery (< 33 completed weeks). In conjunction with iron deficiency anemia at entry to prenatal care, the adjusted odds ratio for very preterm delivery with low zinc intake was 5.44 (95% confidence interval 1.58-18.79). Among the urban poor, a marginal zinc intake during pregnancy may play an important role in the duration of gestation and is associated with increased risk of preterm and very preterm delivery.

Adolescent↗
PubMed1993

A review of the epidemiology of nutrition and adolescent pregnancy: maternal growth during pregnancy and its effect on the fetus.

Maternal growth during adolescent pregnancy and its effects on pregnancy outcome have been a source of controversy. Maternal growth during pregnancy has been difficult to quantify because of the tendency of young and older women to "shrink" in stature with pregnancy. In the Camden Study, maternal growth during pregnancy was monitored with the Knee Height Measuring Device, which measures growth of the lower leg, a body segment less susceptible to "shrinkage." Attempts of other investigators to detect maternal growth during adolescent pregnancy are reviewed here. New data from the Camden Study, also presented, suggest that growing adolescents have infants that weigh less compared to nongrowing adolescents and mature controls (aged 19-29 years). Prior work had suggested that the effects of maternal growth on birth weight were confined to adolescent multiparas. However, with expanded enrollment it was found that infants of growing primiparas and multiparas were both affected. The hypothesis of the competition for nutrients between a still-growing gravida and her fetus is discussed.

Adolescent↗
PubMed1993

Maternal growth during pregnancy and lactation.

Until recently, it was widely accepted that the small amount of statural growth observed in young gravidas was unlikely to be clinically significant, to alter maternal nutritional status, or to threaten fetal growth. We show that this belief reflects incomplete information about growth and the use of inappropriate measuring techniques by investigators. We have done this using illustrations drawn primarily from the Camden Study, a controlled, prospective study of nutrition and growth during adolescent pregnancy. Maternal growth during pregnancy is prevalent and associated with increased gestational weight gain. In the postpartum period it is associated with increased triceps skinfolds, arm fat area and weight retention, all of which occur at caloric intakes comparable with those of pregnant, non-growing adolescents and mature women. Unlike pregnancy where research is continuing, the sequelae of maternal growth during lactation are virtually unstudied.

Adolescent↗
PubMed1993

Amniotic fluid volume estimation in the postdate pregnancy: a comparison of techniques.

OBJECTIVE: To determine the amniotic fluid (AF) volume estimation technique with the greatest diagnostic value with respect to perinatal outcome in the postdate pregnancy. METHODS: One hundred ninety-eight women who were at least 40 weeks' gestation based on ultrasound confirmation or establishment of dates were evaluated twice weekly with nonstress tests (NSTs) and AF volume estimation. Various indices of AF volume were measured and correlated with perinatal outcome. Receiver operating characteristic curves were used to determine optimal cutoff values. RESULTS: There was a significantly larger maximal vertical pocket in those pregnancies with a normal perinatal outcome than in those with abnormal outcome (4.2 +/- 1.4 versus 3.2 +/- 2.0 cm; P = .02). A statistically significant difference was also seen with the AF index (10.0 +/- 4.5 versus 7.5 +/- 5.0 cm; P = .01). Analysis revealed that the optimal cutoff for identifying clinically significant oligohydramnios was a largest vertical pocket less than 2.7 cm, with an adjusted odds ratio for abnormal perinatal outcome of 7.11 (95% confidence interval [CI] 2.79-18.16). Its sensitivity of 50.0% and specificity of 87.9% were superior to the diagnostic value of the AF index of 5 cm, which had a sensitivity of 29.2% and specificity of 89.1%. CONCLUSION: A largest vertical pocket threshold of 2.7 cm had the greatest diagnostic value for identifying the postdate pregnancy at risk for abnormal perinatal outcome, surpassing the AF index and the 2-cm largest vertical pocket rule.

Adult↗