Single vs weekly courses of antenatal corticosteroids for women at risk of preterm delivery: A randomized controlled trial.

CONTEXT: The practice of administering weekly courses of antenatal corticosteroids to pregnant women at risk of preterm delivery is widespread, but no randomized trial has established the efficacy or safety of this practice. OBJECTIVES: To evaluate the efficacy of weekly administration of antenatal corticosteroids compared with a single course in reducing the incidence of neonatal morbidity and to evaluate potential complications of weekly treatment. DESIGN AND SETTING: Randomized, double-blind, placebo-controlled intention-to-treat trial conducted in 13 academic centers in the United States from February 1996 through April 2000. PARTICIPANTS: A total of 502 pregnant women between 24 and 32 completed weeks' gestation who were at high risk of preterm delivery. INTERVENTION: All patients received a complete single course of antenatal corticosteroids (either betamethasone, 12 mg intramuscularly repeated once in 24 hours for 2 doses, or dexamethasone, 6 mg intramuscularly repeated every 12 hours for 4 doses). Participants who had not delivered 1 week after receipt of the single course were randomly assigned to receive either betamethasone, 12 mg intramuscularly repeated once in 24 hours for 2 doses every week until 34 weeks' gestation or delivery, whichever came first (n = 256), or a similarly administered placebo (n = 246). MAIN OUTCOME MEASURE: Composite neonatal morbidity (including severe respiratory distress syndrome, bronchopulmonary dysplasia, severe intraventricular hemorrhage, periventricular leukomalacia, proven sepsis, necrotizing enterocolitis, or perinatal death). RESULTS: Composite morbidity occurred in 22.5% of the weekly-course group vs 28.0% of the single-course group (unadjusted relative risk, 0.80; 95% confidence interval, 0.59-1.10). Neither group assignment nor the number of treatment courses was associated with a reduction in composite morbidity. CONCLUSIONS: Weekly courses of antenatal corticosteroids did not reduce composite neonatal morbidity compared with a single course of treatment. Weekly courses of antenatal corticosteroids should not be routinely prescribed for women at risk of preterm delivery.

Association of ABO incompatibility with elevation of nucleated red blood cell counts in term neonates.

OBJECTIVE: Nucleated red blood cells in the circulation in term neonates have been associated with a wide range of pathologic conditions. We sought to examine the relationship between nucleated red blood cells in the circulation of term neonates and maternal-neonatal blood type compatibility. STUDY DESIGN: We prospectively collected umbilical blood from all live-born neonates delivered at our institution. Venous blood was analyzed for nucleated red blood cells and is reported as the number of nucleated red blood cells per 100 white blood cells. We reviewed maternal and neonatal records for neonates born at > or =37 weeks' gestation for correlative clinical data. Statistical analysis was performed with the SAS statistical software package (version 6.12; SAS Institute, Inc, Cary, NC). Kruskal-Wallis analysis was used as a nonparametric test. RESULTS: We evaluated 1661 neonates delivered during the study period and found a mean (+/-SD) of 9.29 +/- 18.56 nucleated red blood cells per 100 white blood cells (range, 0-327 nucleated red blood cells per 100 white blood cells). Nucleated red blood cell counts were lower in ABO-compatible maternal-fetal dyads (mean +/- SD, 8.29 +/- 12.84 nucleated red blood cells per 100 white blood cells; range, 0-216 nucleated red blood cells per 100 white blood cells) than in ABO-incompatible dyads (mean +/- SD, 13.16 +/- 13.16 nucleated red blood cells per 100 white blood cells; range, 0-327 nucleated red blood cells/100 white blood cells; P =.006). Neonates of mothers with blood groups A and B had significantly lower nucleated red blood cell counts (P <.05). Dyads with maternal type O and neonate type B had significantly higher nucleated red blood cell counts (P <.002). Nonparametric testing determined that type O mother and type B neonate combinations had significantly higher umbilical cord nucleated red blood cell counts (P <.001). CONCLUSION: Maternal-fetal ABO incompatibility is associated with elevation of nucleated red blood cell count in term neonates. Nucleated red blood cell elevation does not always connote a serious pathologic process, however, because ABO incompatibility usually does not adversely affect neonatal outcome. The clinical significance of an elevated nucleated red blood cell count thus is limited.

Umbilical vein white blood cell count as a marker of acidemia in term neonates.

OBJECTIVE: White blood cells are mobilized under both hypoxic and infectious conditions. Intrauterine hypoxia is linked to increased risk of cerebral palsy and is potentiated by the presence of infection. We hypothesized that umbilical vein white blood cell elevation in term neonates is associated with intrauterine acidemia. METHODS: We prospectively evaluated all liveborn neonates delivered at our institution for a 6-month period. Umbilical arterial blood was analyzed for pH and blood gas and venous blood for hematologic indices. Medical records of cases greater than or equal to 37 weeks' gestation were reviewed for correlative data. Student's t-test was used to determine difference of means and Chi-square test for goodness of fit. Pearson coefficients of correlation were applied where appropriate. RESULTS: A total of 1,948 liveborn, term neonates were delivered during the study period; 1,561 cases had white blood cell analysis and arterial blood gas data available. Acidemic cases had higher white blood cell (15.0 vs. 12.4 cells x 10(3)/mm3, P < 0.001), lymphocyte (4.43 vs. 3.59 cells X 10(3)/mm3, P < 0.0001), and neutrophil counts (9.08 vs. 7.71 cells x 10(3)/mm3, P < 0.01). As umbilical artery pH decreased, white blood cells became more prevalent. Likewise, as base deficit deepened, white blood cell counts increased. CONCLUSIONS: This study demonstrates an association between deepening acidemia and increasing white blood cell, lymphocyte, and neutrophil counts. Although statistically different, mean white blood cell counts for acidemic and nonacidemic cases are fairly close, limiting the clinical applicability in determining whether pathology is present in an individual case.

Nucleated red blood cells as a marker of acidemia in term neonates.

OBJECTIVES: Nucleated red blood cells are produced in increased numbers under hypoxic conditions. We sought to examine the relationship between nucleated red blood cell count in the circulations of term neonates and other possible markers of fetal hypoxia. STUDY DESIGN: We prospectively collected umbilical blood from all live-born neonates delivered at our institution. Arterial blood was analyzed for pH and blood gas values. Venous blood was analyzed for nucleated red blood cell count. We reviewed the medical records for maternal data and neonatal outcomes of gestations of >/=37 weeks' duration. RESULTS: We evaluated 1561 cases. The mean nucleated red blood cell count per 100 white blood cells was 9.2 +/- 18.1 (range, 0-327). Nucleated red blood cell counts were higher in infants with pH <7.20 (P =.001). Both patients with respiratory acidemia and patients with uncompensated metabolic acidemia had elevated nucleated red blood cell counts (P =.013 and P =.014, respectively). As umbilical artery pH and base excess decreased, nucleated red blood cells became more prevalent. Elevated nucleated red blood cell counts were associated with presence of meconium (P =. 020) and neonatal intensive care unit admission (P =.024). CONCLUSIONS: We found that nucleated red blood cell counts vary widely in the circulation of term neonates. Elevated nucleated red blood cell counts are associated with fetal acidemia, meconium, and neonatal intensive care unit admission.

Accelerated fetal lung maturity profiles and maternal cocaine exposure.

OBJECTIVE: To determine the effect of maternal cocaine exposure on fetal lung maturity as measured by surfactant-albumin ratios determined by the TDx-FLM test. METHODS: A case-control study design was used to compare fetal lung maturity as assessed by a surfactant-albumin ratio assay (TDx-FLM) in amniotic fluid (AF) obtained from women who were known to use cocaine and those who were not known to use cocaine during the study pregnancy. Multiple logistic regression procedures were used to control for gestational age and possible confounders, such as obstetric and nonobstetric complications, other substance abuse, race, infant sex, and payer status. RESULTS: Maternal cocaine use during pregnancy was associated with an accelerated fetal lung maturity profile (adjusted odds ratio [OR] 2.04, 95% confidence interval [CI] 1.04-4.00) as determined by the TDx-FLM test. Other variables found to be statistically significant predictors of a mature fetal lung profile were cigarette smoking during the current pregnancy (OR 1.61, 95% CI 1.02-2.56). Preterm labor, preterm rupture of membranes, nonobstetric illness during pregnancy, and exposure to other abused substances were not associated with accelerated fetal lung maturity. CONCLUSION: Maternal cocaine use during pregnancy is associated with a doubling of the probability of a mature fetal lung profile as determined by TDx-FLM analysis of AF. Tobacco use is also a predictor of accelerated fetal lung maturity profiles.

Posterior urethral valves in successive generations.

Posterior urethral valves (PUV) are a frequent cause of urinary tract obstruction in infant males and may be diagnosed by antenatal ultrasound. PUV have been observed in siblings and in identical twins. However, genetic factors in PUV are poorly understood. In this article, we report the occurrence of PUV diagnosed antenatally in a fetus whose father and paternal uncle were both treated for PUV in childhood. This is the first reported case of PUV that we are aware of occurring in successive generations.