摘要:

ObjectiveTo evaluate the presence of fetal fibronectin in the cervix and vagina as a screening test for spontaneous preterm birth.MethodsTwo thousand nine hundred twenty-nine women at ten centers were routinely screened every 2 weeks from 22–24 to 30 weeks for cervical and vaginal fetal fibronectin. A positive test was defined as a value equal to or greater than 50 ng/mL. The relation between a positive test at four gestational ages and spotaneous pretern birth at various intervals after the test was determined.ResultsIn each testing period 3–4% of the fetal fibronectin tests were positive. The correlation between cervical and vaginal fetal firbonectin at the same visit was always approximately 0.7 (P< .001), and that between cervical or vaginal fetal fibronectin in consecutive visits was between 0.17 and 0.25 (P< .001). The sensitivity of fetal fibronectin at 22–24 weeks to predict spontaneous preterm birth at less than 28 weeks was 0.63, and the relative risk for a positive versus negative test was 59. The specificity was always 96–98%, whereas the positive predictive value rose from 13% to 36% as the upper limit of the definition of preterm birth was increased from less than 28 to less than 37 weeks. The relative risk for spontaneous preterm birth after a positive fetal fibronectin test compared with a negative fetal fibronectin test varied substantially by testing period and by the definition of spontaneous preterm birth, but always remained greater than 4 and statistically significant.ConclusionA positive cervical or vaginal fetal fibronectin test at 22–24 weeks predicted more than half of the spontaneous preterm births at less than 28 weeks (sensitivity 0.63). As the definition of spontaneous preterm birth was extended to include later gestational ages or when the fetal fibronectin test was performed later in pregnancy, the level of association between a positive fetal fibronectin test and spontaneous preterm birth, while remaining highly significant, tended to decrease. Although fetal fibronectin is an excellent test for predicting spontaneous preterm birth, we present no evidence that the use of this test will result in a reduction in spontaneous preterm birth.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo evaluate the usefulness of fetal fibronectin and home uterine contraction assessment in predicting preterm birth (before 34 weeks) in at-risk asymptomatic women.MethodsOne hundred fifty women were enrolled prospectively; five were lost to follow-up, leaving 145 women available for analysis. Because patients with preterm labor before 34 weeks' gestation most commonly develop this problem after 28 weeks, the period 26–28 weeks' gestation was selected prospectively as the first window for prediction and study analysis. Eighty-five of 145 asymptomatic women at high risk for preterm birth had both home uterine contraction assessment of 2 hours per day and one or more cervical sampling(s) for fetal fibronectin measurement at 26–28 weeks. A positive home uterine contraction assessment was defined as contractions exceeding two per hour averaged over the 2-week study interval. Positive fetal fibronectin was defined as greater than 50 ng/mL.ResultsFourteen of the 85 women (16.5%) delivered before 34 weeks. Home uterine contraction assessment alone had a sensitivity, specificity, positive predictive value, and negative predictive value for preterm birth of 64, 85, 45, and 92%, respectively; fetal fibronectin alone was associated with values of 43, 89, 43, and 89%, respectively. A positive home utrine contraction assessment was associated with a relative risk (RR) for preterm birth of 5.9 (95% confidence interval [CI] 2.4–14.2), whereas a positive fetal fibronectin demonstrated an RR of 3.8 (95% CI 1.5–9.4). When both assessments were positive, all patients delivered before 34 weeks and there was an RR of 27.0 (95% CI 8.7–84.1) compared with those with both tests being negative. Only two patients with both tests negative delivered before 34 weeks (negative predictive value 96%).ConclusionBoth the home uterine contraction assessment and fetal fibronectin accurately predicted preterm birth before 34 weeks. When both tests were combined, the predictive ability improved substantially.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine the relation between vaginal and upper genital tract infection and cervical-vaginal fetal fibronectin levels.MethodsWe screened 2899 women at ten centers every 2 weeks from 23–24 to 30 weeks' gestation for cervical and vaginal fetal fibronectin. A positive test was defined as a level of at least 50 ng/mL. The relation between a positive test and bacterial vaginosis at 23–24 weeks at clinical or histologic chorioamnionitis at delivery plus neonatal sepsis was determined.ResultsFetal fibronectin was present in 4.0% of cervical and/or vaginal samples at 23–24 weeks and was nearly twice as common in women with bacterial vaginosis. Adjusting for the presence of bacterial vaginosis, race, and parity, women positive for fetal fibronectin were much more likely to have clinical chorioamnionitis (mean ± standard deviation gestational age 30.6 ± 4.1 weeks), with an odds ratio of 16.4 and 95% confidence interval of 7.1–37.8, and neonatal sepsis (6.3 and 2.0–20.0, respectively), than those who were fetal fibronectin-negative. A positive cervical fetal fibronectin test was a better predictor of clinical chorioamnionitis and neonatal sepsis than was a vaginal test or a combination of vaginal and cervical tests. Among 40 women who delivered before 32 weeks and had placental histology available for evaluation, ten had a positive cervical and/or vaginal fetal fibronectin test before delivery; all ten had histologic evidence of chorioamnionitis, compared with only 13 of 30 women (43%) who were fetal fibronectin-negative (P= .02).ConclusionWomen with bacterial vaginosis were more likely to have a positive fetal fibronectin test than uninfected women. Women with a positive fetal fibronectin test who delivered before 32 weeks' gestation all had evidence of histologic chorioamnionitis. Women positive for fetal fibronectin also had a 16-fold increase in clinical chorioamnionitis and a sixfold increase in neonatal sepsis. There is strong evidence that upper genital tract infection and cervical and/or vaginal fetal fibronectin are closely linked.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine if microalbumin excretion can predict the development of premature delivery.MethodsThe possibility of predicting, early in pregnancy, the development of a preterm delivery using urinary albumin was investigated in 1422 nulliparous women recruited prospectively. A first morning urine sample was collected at three occasions during pregnancy (8–14, 15–24, 25–24 weeks' gestation) for the determination of urinary albumin excretion.ResultsNo significant correlation was found between gestational age and urinary albumin (absolute concentration, albumin-creatinine ratio, or relative clearance of albumin) at either visit (rranging from −0.043 to 0.036;P> .1). The incidence of preterm birth was similar for the first and fourth quartiles of the urinary albumin-creatinine ratio for the second visit (5.8 and 5.7%, respectively).ConclusionUrinary albumin is not a useful marker of preterm birth in a low-risk general population.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo assess the effectiveness of a joint-specialty society and health department statewide peer-review program to reduce cesarean rates.MethodsForty-five of the 165 hospitals with active delivery services were reviewed between 1989 and 1993. Differences in total and repeat cesarean rates and vaginal birth after cesarean (VBAC) rates were compared by hospital review status using Studentttests and linear regression for the years before and after completion of the program.ResultsReviewed hospitals reduced their total cesarean rate by 3% and repeat cesarean rate 0.7%, and increased their VBAC rae by 14.6% compared with nonreviewed hospitals, for which the respective reduction in rates was 1%, 0.6%, and 12.7%. Statistically, there was no difference between reviewed and nonreviewed hospitals in terms of rate changes.ConclusionThis joint-specialty society and health department peer review had no apparent impact on cesarean rates.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo compare the trends and obstetric outcomes of pregnancy in teenage women with those of adult women.MethodsWe analyzed a 19-year (1975–1993) computerized perinatal data base with on 69,096 births collected prospectively from a single inner-city tertiary medical center.ResultsOf all the births, 1875 (2.7%) were to teenagers 12–15 years old and 17,359 (25.3%) were to teenagers 16–19 years old. Over the study period, the number and proportion of births to teenagers of both age groups declined (P< .001 in both cases). The proportions of teenagers 12–15 and 16–19 years old were highest among blacks (4.1% and 28.1%, respectively), followed by Hispanics (2.4%, 24.7%) and whites (1.6%, 23.1%). More than 95% of teenagers had no private health insurance coverage (staff), significantly higher than the 81.6% of mothers aged 20 years of older (P< .001). More than 8.1% of teenagers 12–15 years old had two or fewer prenatal care visits, significantly higher than 6.8% for teenagers 16–19 years old and 7.1% for adults (P< .001. The average gestational age and birth weight were significantly lower for teenagers 12–15 years old compared with those 16–19 years old and adults. Patients 16–19 years of age had longer gestational age and higher birth weight than the adults. The proportion of primary cesarean deliveries among teenagers 12–15 years old was 11.6%, significantly higher than 9.4% for those 16–19 years old and 10.2% for adults (P< .001).ConclusionOn average, females 16–19 years old had better obstetric outcomes than adults, whereas obstetric outcomes for those 12–158 years old were worse than for adults. Therefore, all teenagers should not be grouped together when their obstetric outcomes are compared with those of adults.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine whether use of chorionic villus sampling and amniocentesis varies by racial-ethnic group and, if so, whether this variation is reflected in the prevalence of Down syndrome-affected births to women age 35 and older, the ages at which prenatal diagnosis is offered currently.MethodsMedical charts of 238 women 35 years of age and older presenting for care at the University of California at San Francisco by 20 gestational weeks in 1993 and 1994 were reviewed to assess prenatal diagnostic test use. The prevalence of Down syndrome-affected births in California during 1983–1991 was obtained from the Birth Defects Monitoring Program.ResultsLatinas and African-American women were much less likely to undergo prenatal diagnosis than were whites and Asians. Odds ratios (OR) and 95% confidence intervals (CI), with white women serving as the reference group, were as follows: Asians 1.16 (0.57–2.36), Latinas 0.19 (0.08–043), and African-Americans 0.19 (0.07–0.49). Trends persisted, at diminished magnitude, after adjustment for socioeconomic characteristics: OR for Asians 1.77 (0.78–3.98), Latinas 0.28 (0.09–0.83), and African-Americans 0.33 (0.10–1.10). Non-white women age 35 and older were significantly more likely than white women to give birth to a Down syndrome-affected infant: risk ratios for Asians 1081 (1.61–2.03), Latinas 3.00 (2.74–3.28), African-Americans 1.86 (1.63–2.11).ConclusionRacial-ethnic differences exist in prenatal diagnostic test use and associated outcomes in women age 35 and older. Socioeconomic factors are partially responsible; patient education and preferences may play a role.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine if an additive effect exists between antenatal corticosteroid administration and postnatal surfactant therapy in the prevention of respiratory distress syndrome (RDS) in preterm infants.MethodsA randomized, double-blind trial was conducted from April 1990 to June 1994, in which dexamethasone (5 mg every 12 hours for a total of four doses) or saline was given to women at risk for delivery at 24–29 weeks' gestation. At birth, prophylactic surfactant was administered to all study infants. Main outcome measures were RDS occurrence and severity. Secondary clinical end points included broncho-pulmonary dysplasia, pneumothorax, patent ductus arteriosus, necrotizing enterocolitis, retinopathy, intraventricular hemorrhage, and death.ResultsSeventy-five of the 124 randomized subjects delivered 96 infants within the studied gestational age range (dexamethasone,n= 54; placebo,n= 42). Similar maternal demographics and obstetric complications were noted between study groups. A greater proportion of infants were delivered from multi-fetal gestations in the dexamethasone cohort (26 of 54 versus 12 of 42 newborns;P= .05). There were no significant differences in the occurrence or severity of RDS between the dexamethasone and placebo infants (none or mild, 67 versus 67%; moderate, 24 versus 26% severe, 9 versus 7%, respectively), or differences in any of the secondary clinical outcomes. The study size was sufficient to exclude a 50% reduction in RDS incidence as a consequence of dexamethasone exposure. An analysis restricted to singletons (dexamethasone,n= 28; placebo,n= 30) revealed similar overall occurrence of intraventricular hemorrhage (12 of 28 versus ten of 30;P= .63), but significantly fewer grade 3 and 4 intraventricular hemorrhages in dexamethasone-exposed neonates (two of 12 versus six of ten;P= .048).ConclusionAntenatal dexamethasone does not appear to decrease the incidence or severity of RDS in surfactant-treated infants delivered at 24–29 weeks' gestation, but may be associated with reduced severity of intraventricular hemorrhages in surfactant-treated singletons in this gestational age range.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine the effect of single-dose penicillin given at birth on the rate of early-onset group B streptococcal (GBS) invasive disease in an inner-city population.MethodsLaboratory-based surveillance of GBS disease from 1972–1994 at Parkland Memorial Hospital and Children's Medical Center in Dallas, Texas, was reviewed retrospectively. All infants born at Parkland Memorial Hospital from January 1, 1972 to December 31, 1994, or a total of 259,049 live births, were included. Early-onset (within 3 days) GBS disease rates were compared for each of five observation groups to determine the efficacy of a single dose of aqueous penicillin G (50,000 U for infants weighing 2000 g or more and 25,000 U for those weighing less than 2000 g) administered intramuscularly within 1 hour of delivery for prevention of GBS disease.ResultsThe rates of early-onset GBS disease were compared in five observation groups: A) pre-study, January 1, 1972 to December 3, 1977—no GBS prophylaxis; B) prospective, controlled intervention study, December 4, 1977 to May 31, 1981, including infants who received a single dose of penicillin at birth (group B1) and those who did not (group B2); C) universal penicillin prophylaxis, June 1, 1981 to October 31, 1986; and D) no routine penicillin prophylaxis, November 1, 1986 to December 31, 1994. The incidence of early-onset GBS disease in the penicillin groups (B1, C) was significantly lower than that in the untreated groups (A, B2, D): 0.25 and 0.63 per 1000 versus 1.59, 1.19, and 1.95 per 1000, respectively (P≤ .03). The incidence of late-onset GBS disease was unaffected by penicillin prophylaxis, and there was no increase in the incidence of disease caused by penicillin-resistant pathogens or associated mortality in penicillin-treated infants: 2.2 and 2.1 per 1000 versus 1.6 and 3.3 per 1000 for disease; 1.0 and 0.5 per 1000 versus 0.4 and 0.3 per 1000 for deaths.ConclusionUniversal administration of single-dose pencillin at birth is a safe and effective intervention for the prevention of early-onset GBS disease.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo establish the gestational age trends of amniotic fluid index (AFI) in uncomplicated twin pregnancies.MethodsAmniotic fluid index was measured in uncomplicated twin pregnancies seen between 1985 and 1993 and meeting the following criteria: 1) no maternal medical or obstetric complications, 2) normal growth of both twins by serial ultrasound, and 3) normal amniotic fluid volume by ultrasound. Amniotic fluid index was measured by adding the deepest vertical pockets in four quadrants, defined by the umbilicus and linea nigra. The relation between gestational age and AFI was evaluated using linear regression analysis.ResultsTwo hundred eighty-two sets of twins were considered uncomplicated; 1101 AFI measurements were performed on these pregnancies between 25.5 and 40.5 weeks' gestation. Percentile values for AFI were determined according to gestational age. The regression equation relating the median AFI to gestational age was: AFI = 19.4–0.12 × gestational age (P= .03). The R2value was 0.04.ConclusionGestational age trends in normative AFI measurements for twin pregnancies have been established. Their use will facilitate a more reproducible, quantitative diagnosis of oligohydramnios in twins, compared, with subjective, qualitative approaches to amniotic fluid volume assessment.

ISSN:0029-7844    

出版商:OVID    

年代:1996

数据来源: OVID