摘要:

ObjectiveTo develop a current national fetal growth curve that can be used as a common reference point by researchers to facilitate investigations of the predictors and consequences of small and large for gestational age delivery.MethodsSingle live births to United States resident mothers in 1991 (n= 3,134,879) were used for the development of this curve, which was compared with four previously published fetal growth curves. Techniques were developed to address cases with implausible birth weightgestational age combinations and to smooth fetal growth curves across gestational age categories.ResultsIn general, the previously published fetal growth curves underestimated the 1991 United States reference curve. This underestimation is most apparent during the latter weeks of gestation, approximately 33–38 weeks.ConclusionOur findings indicate that the prevalence of fetal growth restriction (FGR) will vary markedly, depending on the fetal growth curve used. Furthermore, many previously published fetal growth curves no longer provide an up-to-date reference for describing the distribution of birth weight by gestational age and for determining FGR that is consistent with the most recent live birth data for the entire United States.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine if perinatal morbidity and mortality differ in growth-retarded, small for gestational age (SGA), premature infants and appropriate for gestational age (AGA) infants.MethodsAll consecutive, singleton, nondiabetic, preterm pregnancies delivered over a 15-year period were analyzed. Infants were categorized as SGA (at or below the tenth percentile) or AGA (11th to the 89th percentiles), then stratified by birth weight and gestational age categories. Perinatal morbidity and mortality were examined.ResultsWe studied 4183 preterm deliveries, 1012 of them SGA and 3171 of them AGA. Overall, we found significantly higher rates of fetal and neonatal death in the SGA group. Stratification by gestational age revealed significantly higher rates of neonatal death for the SGA group compared with the AGA group in each gestational age category. Overall, comparison also revealed significantly higher rates of fetal heart rate abnormality in the SGA group but no difference in neonatal sepsis, birth trauma, cesarean delivery, hyaline membrance disease, or congenital anomalies.ConclusionGrowth-retarded premature infants have a significantly higher risk of morbidity and mortality, both before and after delivery, than do appropriately grown infants.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo evaluate the influence of acid-base status at birth and Apgar scores on survival in very low birth weight infants.MethodsWe evaluated 1073 infants born alive and weighing 500–1000 g during 1979–1991; 658 had umbilical artery gas values examined. Apgar scores were assigned at 1 and 5 minutes after birth. Umbilical artery blood samples were collected at delivery for pH, carbon dioxide pressure (PCO2), and bicarbonate. Infants were grouped at 23–24, 25–26, 27–28, and 29 weeks or more. Using survival as the dependent variable, multiple logistic regression analyses were performed controlling for gestational age, birth weight, plurality, antenatal glucocorticoid use, mode of delivery, and year of birth, as well as for Apgar scores and cord blood gases.ResultsIn every gestational age grouping, compared with infants with a pH lower than 7.05, survival was higher in infants with an umbilical artery pH of 7.05 or higher, significantly so at 27–28 weeks. There was no consistent relationship between umbilical artery PCO2or bicarbonate and survival. However, with the exception of the 1-minute Apgar score at 23–24 weeks, the relationship of Apgar scores to survival was significant in all gestational age periods. Using multiple logistic regression analyses, the only significant relationships between any of the cord blood gases, Apgar scores, and mortality involved low 1-minute (odds ration [OR] 2.7 [95% confidence interval (CI) 2.0–3.6]) and low 5-minute Apgar scores (OR 2.8 [95% CI 2.0–3.8]) and a bicarbonate less than 21 mEq/L (OR 1.6 [95% CI 1.1–2.4]).ConclusionOne- and 5-minute Apgar scores are better predictors of survival than umbilical artery blood gases in neonates weighing 500–1000 g at birth.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo investigate the hypothesis that meconium aspiration syndrome, the major hazard of meconium during labor, may be associated with superimposed fetal acute acidemia.MethodsUmbilical artery blood gases were measured in 7816 term pregnancies with meconium in the amniotic fluid (AF) and the results were correlated with intrapartum and neonatal outcomes.ResultsSixty-nine (1%) infants developed meconium aspiration syndrome and 31 (45%) of these were in association with fetal acidemia at birth. Moreover, umbilical blood gas analysis and intrapartum events suggested that the fetal acidemia linked to meconium aspiration was an acute event rather than a long-duration process, which might be expected if meconium was itself a marker of an antecedent fetal asphyxial event.ConclusionMeconium in the AF may be a fetal environmental hazard when acidemia supervenes rather than solely a marker of preexisting fetal compromise leading to the release of meconium.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine the influence of maternal blood contamination on amniotic fluid (AF) glucose and white blood cell count (WBC).MethodsAmniotic fluid from 23 preterm, nondiabetic pregnant women was studied. Maternal blood was added to the AF at increasing concentrations, and glucose and WBCs were assessed.ResultsThe median AF glucose in the uncontaminated specimen was 43 mg/dL (range 11–86). Median glucose levels were unchanged by the addition of maternal blood until a mean ± standard deviation AF red blood cell count of 63,000 ± 22,000/mm3was exceeded, at which time the meadian glucose level significantly increased to a median of 45 mg/dL (range 19–90). The ratio of observed to expected values of WBCs ranged from 0.12–1.8, regardless of the level of maternal blood contamination.ConclusionGlucose levels in preterm AF-containing maternal blood are accurate in all except the most heavily contaminated specimens. Accurate determination of the WBC in contaminated AF is difficult.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine the associations between maternal characteristics, intrapartum events, and neonatal sepsis by multivariate analysis.MethodsWe enrolled 823 women from a high-risk population and analyzed maternal and neonatal demographic and outcome variables with univariate analysis and multivariate logistic modeling.ResultsTwo-hundred sixteen women (26%) were colonized with group B streptococci, 82 (10%) developed chorioamnionitis, and 141 (17%) delivered prematurely. Cultureproven neonatal sepsis or meningitis was found in 15 of 833 (1.8%) neonates, and 101 of the remaining 818 (12.3%) infants were suspected to have sepsis or pneumonia. Multivariate analysis of risk factors for proven neonatal sepsis demonstrated a statistically significant association with decreasing gestational age, duration of internal monitoring for more than 12 hours (odds ratio [OR] 7.2, 95% confidence interval [CI] 1.6–32.2), maternal group B streptococcal infection (OR 4.2, 95% CI 1.4–13.1), chorioamnionitis (OR 4.4, 95% CI 1.2–16.1), and endometritis (OR 6.4, 95% CI 1.2–34.2).ConclusionThrough the use of multivariate modeling, we determined that chorioamnionitis or endometritis, preterm delivery, group B streptococcal colonization, and a prolonged duration of internal monitoring are independent risk factors for neonatal sepsis. We postulate that the presence of a foreign body that traverses the birth canal may facilitate ascending peripartal infection.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo examine pregancy rates among women infected with human immunodeficiency virus (HIV).MethodsWe used data from an ongoing survey of medical records of 3915 women who were 15–44 years of age, infected with HIV, and who received care between January 1990 and August 1994 in more than 90 clinics, hospitals, and private practices in 11 United States cities.ResultsAt enrollment, 570 (14%) of these women were pregnant. Pregnancy rates at entry varied significantly (P≤ .05) by age in years (15–19 [47%], 20–24 [30%], 25–29 [18%]; 30–34 [11%]; 35–39 [5%]; 40–44 [2%]); clinical status (with AIDS opportunistic illness [3%], without AIDS opportunistic illness [17%]); and race-ethnicity (white [12%], black [17%], Hispanic [8%], Asian [0%], Native American [30%]) but not by mode of exposure (injecting drug use [10%], heterosexual contact [15%], and blood transfusion [12%]). After enrollment, 5.8% of women became pregnant each year. New pregnancies were significantly less likely to occur among women with an AIDS opportunistic illness (adjusted rate ratio 0.4, 95% confidence interval [CI] 0.2–0.6), and significantly more likely to occur among women who were less than 25 years of age (adjusted rate ratio 8.3, 95% CI 5.3–13.2) and who were black (adjusted rate ratio 1.6, 95% CI 1.2–2.1). Among women who were pregnant at enrollment or during observation, 12% were pregnant more than once.ConclusionsHigh rates of pregnancy at entry to medical care among HIV-infected women stress the importance of counseling and voluntary testing as routine obstetricgynecologic practice. In some groups, rates ofnew pregnancies remain high; standard HIV care for women should include family planning services and assurance that if a woman chooses to practice contraception, contraceptives will be available and affordable.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine the maternal and fetal outcomes of pregnancy in women with sickle cell disease.MethodsThe subjects were part of a cohort recruited from 19 centers for a prospective study of the clinical course of sickle cell disease. Each participant was evaluated using a structured protocol in which steady-state data and information on both sickle- and non-sickle-related events were colleted. The rates of antepartum and intrapartum complications were tallied for pregnancies carried to delivery. Fetal outcome was assessed according to gestational age, birth weight, and Apgar score. Differences among genotypes in event rates were assessed using Fisher exact test. Differences in gestational age and birth weight, and predictors of these outcomes, were assessed using analyses of covariance.ResultsTwo hundred eighty-six of the 445 reported pregnacies proceeded to delivery. Non-sickle-related antepartum and intrapartum complication rates were comparable with those of African-American women who did not have sickle cell disease. One of the two deaths observed during this study was directly related to the presence of sickle cell disease. Rates of maternal morbidity from sickle cell disease were the same during pregancy as during the nonpregnant state. Ninety-nine percent of those pregnancies carried to delivery resulted in a live birth. Twenty-one percent of the infants born to women of the SS genotype were small for gestational age (SGA). Preclampsia and acute anemic events were identified as risk factors for SGA infants.ConclusionThose caring for women with sickle cell disease should support them if they desire to have children.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo evaluate diurnal variation in blood pressure (BP) in normal gravidas and those with preeclampsia, using ambulatory BP monitoring.MethodsA cross-sectional comparative observational study was performed in three teaching hospital maternity units. Twenty-four normotensive and 24 preeclamptic women who were similar in age, weight, and mean duration of gestation (35 weeks) were studied. Diurnal variation and BP measurement were assessed using ambulatory BP monitors validated for use in pregnancy and for which normal reference ranges for pregnancy have been derived.ResultsAt night, the BP fall was less in preeclamptic women than in normotensive women. The day-night BP difference decreased as average BP rose (diastolic gradient = −0.54 [95% confidence interval (CI) −0.77 to −0.31], systolic gradient = −0.36 [95% CI −0.58 to −0.14], where gradient denotes a unit increase in BP leading to an increase or decrease in the day-night difference).ConclusionThe decrease in day-night BP difference observed in preeclampsia is inversely related to average BP. This blunting of the day-night BP difference may be a useful adjunctive measure of disease severity in preeclampsia.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo assess the accuracy of a questionnaire developed by the Centers for Disease Control and Prevention (CDC), given to pregnant women for identification of children at risk for lead poisoning.MethodsThe study population consisted of all 314 new prenatal patients enrolled in health department clinics in 1990–1992. Lead was measured in venous blood, and patients completed written questionnaires to gather information about lead expoure risk factors. The relationship between elevated maternal blood lead levels (at or greater than 10 μg/dL or 0.483 μmol/L) and responses to the CDC questionnaire and other questions were examined using χ2statistical analysis.ResultsTwo hundred ninety-nine women provided responses to questions about lead exposure risk. Thirty-nine women (13%) had elevated blood lead levels. A woman with a positive response to at least one CDC question was more likely to have elevated blood lead than a woman who answered negatively to all four CDC questions (relative risk = 2.39,95% confidece interval 1.17–4.89;P= .01). Using the CDC definition of high risk (“yes” to at least one question), the questionnaire had a sensitivity of 75.7% and a negative predictive value of 93.1%. A questionnaire that combined housing conditions, smoking status, and high consumption of canned foods had a sensitivity of 89.2% and a negative predictive value of 96.4%. A high prevalence of elevated blood lead in children living with women with elevated blood lead was observed.ConclusionQuerying pregnant women about risk factors for lead exposure can aid in assessing prenatal lead exposure risk. The sensitivity and negative predictive value of the CDC questionnaire, when used with high-risk women, are comparable to its reported accuracy in young children.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID