Prenatal diagnosis of a lean umbilical cord: a simple marker for the fetus at risk of being small for gestational age at birth.
OBJECTIVE: The purpose of this study was to investigate whether the prenatal diagnosis of a 'lean' umbilical cord in otherwise normal fetuses identifies fetuses at risk of being small for gestational age (SGA) at birth and of having distress in labor. The umbilical cord was defined as lean when its cross-sectional area on ultrasound examination was below the 10th centile for gestational age. METHOD: Pregnant women undergoing routine sonographic examination were included in the study. Inclusion criteria were gestational age greater than 20 weeks, intact membranes, and singleton gestation. The sonographic cross-sectional area of the umbilical cord was measured in a plane adjacent to the insertion into the fetal abdomen. Umbilical artery Doppler waveforms were recorded during fetal apnea and fetal anthropometric parameters were measured. RESULTS: During the study period, 860 patients met the inclusion criteria, of whom 3.6% delivered a SGA infant. The proportion of SGA infants was higher among fetuses who had a lean umbilical cord on ultrasound examination than among those with a normal umbilical cord (11.5% vs. 2.6%, p < 0.05). Fetuses with a lean cord had a risk 4.4-fold higher of being SGA at birth than those with a normal umbilical cord. After 25 weeks of gestation, this risk was 12.4 times higher when the umbilical cord was lean than when it was of normal size. The proportion of fetuses with meconium-stained amniotic fluid at delivery was higher among fetuses with a lean cord than among those with a normal umbilical cord (14.6% vs. 3.1%, p < 0.001). The proportion of infants who had a 5-min Apgar score < 7 was higher among those who had a lean cord than among those with normal umbilical cord (5.2% vs. 1.3%, p < 0.05). Considering only patients admitted in labor with intact membranes and who delivered an appropriate-for-gestational-age infant, the proportion of fetuses who had oligohydramnios at the time of delivery was higher among those who had a lean cord than among those with a normal umbilical cord (17.6% versus 1.3%, p < 0.01). CONCLUSION: We conclude that fetuses with a lean umbilical cord have an increased risk of being small for gestational age at birth and of having signs of distress at the time of delivery. (+info)
Prophylactic cefazolin in amnioinfusions administered for meconium-stained amniotic fluid.
OBJECTIVE: To determine if amnioinfusion with an antibiotic solution decreased the rate of clinical chorioamnionitis and puerperal endometritis in patients with meconium-stained amniotic fluid. METHODS: Patients in labor at 36 weeks of gestation or greater with singleton pregnancies and meconium-stained amniotic fluid were randomized to receive either cefazolin, 1 g/1,000 mL, of normal saline (n = 90) or normal saline (n = 93) amnioinfusion. Rates of clinically diagnosed chorioamnionitis and endometritis and of suspected and culture-proven neonatal infection were determined. RESULTS: Between the study and control groups, the incidences of clinical chorioamnionitis (7.8% vs. 8.6%), endometritis (2.4% vs. 3.5%), aggregate intrauterine infection (10.0% vs. 11.8%), suspected neonatal infection (17.8% vs. 21.5%), and proven neonatal infection (0.0% vs. 2.2%) were not significantly different. CONCLUSIONS: Prophylactic use of cefazolin in amnioinfusions did not significantly reduce rates of maternal or neonatal infection in patients with meconium-stained amniotic fluid. (+info)
Bile acid patterns in meconium are influenced by cholestasis of pregnancy and not altered by ursodeoxycholic acid treatment.
BACKGROUND: Data on meconium bile acid composition in newborn babies of patients with intrahepatic cholestasis of pregnancy (ICP) are relatively scant, and changes that occur on ursodeoxycholic acid (UDCA) administration have not been evaluated. AIMS: To investigate bile acid profiles in meconium of neonates from untreated and UDCA treated patients with ICP. Maternal serum bile acid composition was also analysed both at diagnosis and delivery to determine whether this influences the concentration and proportion of bile acids in the meconium. PATIENTS/METHODS: The population included eight healthy pregnant women and 16 patients with ICP, nine of which received UDCA (12.5-15.0 mg/kg body weight/day) for 15+/-4 days until parturition. Bile acids were assessed in the meconium by gas chromatography-mass spectrometry and in maternal serum by high performance liquid chromatography. RESULTS: Total bile acid and cholic acid concentrations in the meconium were increased (p<0.01) in newborns from patients with ICP (13.5 (5.1) and 8.4 (4.1) micromol/g respectively; mean (SEM)) as compared with controls (2.0 (0.5) and 0.8 (0.3) micromol/g respectively), reflecting the total bile acid and cholic acid levels in the maternal serum (r = 0.85 and r = 0.84, p<0.01). After UDCA administration, total bile acid concentrations decreased in the mother ( approximately 3-fold, p<0. 05) but not in the meconium. UDCA concentration in the meconium showed only a 2-fold increase after treatment, despite the much greater increase in the maternal serum (p<0.01). Lithocholic acid concentration in the meconium was not increased by UDCA treatment. CONCLUSIONS: UDCA administration does not influence the concentration and proportion of bile acids in the meconium, which in turn are altered by ICP. Moreover, this beneficial treatment for the mother does not increase meconium levels of potentially toxic metabolites of UDCA such as lithocholic acid. (+info)
Immunoassay and GC-MS procedures for the analysis of drugs of abuse in meconium.
The analysis of meconium specimens for metabolites of substances of abuse is a relatively accurate method for the detection of fetal exposure to drugs. Most of the methods reported in the literature before the early 1990s relied on radioimmunoassays. The purpose of this study was to develop and validate methods for meconium sample preparation for the screening and gas chromatography-mass spectrometry (GC-MS) confirmation of meconium extracts for cannabinoids, cocaine, opiates, amphetamines, and phencyclidine. EMIT and TDx immunoassays were evaluated as screening methods. The sample preparation method developed for screening included extraction and purification prior to analysis. Cutoff levels were administratively set at 20 ng/g for 11-nor-delta9-THC-9-COOH (THCCOOH) and phencyclidine and at 200 ng/g for benzoylecgonine, morphine, and amphetamines, although lower levels could be detected in meconium using the EMIT-ETS system. Ninety-five meconium specimens were subjected to the screening procedure with GC-MS confirmation of presumptive positives. In addition, 30 (40 for cocaine) meconium specimens were subjected to GC-MS analysis for all analytes regardless of the screening results to determine the false-negative rate, if any, of the immunoassay. Although there were no false negatives detected, the GC-MS confirmation rate for the immunoassay-positive specimens was generally low, ranging from 0% for amphetamines to 75% for opiates. The lowest rate of confirmed positives was found with the cannabinoids, suggesting that tetrahydrocannabinol (THC) metabolites other than free 11-nor-9-carboxy-delta9-THC may be major contributors to the immunoassay response in meconium. (+info)
Identification and analysis of the major metabolites of cocaine in meconium.
A gas chromatographic-mass spectrometric (GC-MS) method was used for the simultaneous analysis of cocaine and its metabolites (norcocaine, benzoylecgonine, norbenzoylecgonine, ecgonine methylester, cocaethylene, and the o-, m, and p-hydroxy derivatives of cocaine and benzoylecgonine) in meconium specimens collected from newborns prenatally exposed to the drug in an effort to determine which of these metabolites are more relevant in the confirmation of immunoassay-positive specimens. Significant metabolites included benzoylecgonine and its m- and p-hydroxy derivatives. Reanalysis of immunoassay-positive meconium specimens that previously failed to confirm by GC-MS for benzoylecgonine revealed that the GC-MS confirmation rate could be substantially enhanced by inclusion of m- and p-hydroxybenzoylecgonine in the analysis along with benzoylecgonine. Several specimens were found to be positive for hydroxylated derivative(s) in the absence of benzoylecgonine itself. (+info)
Level of in utero cocaine exposure and neonatal ultrasound findings.
OBJECTIVE: To assess whether there is an association between the level of in utero cocaine exposure and findings on neonatal cranial ultrasound, controlling for potentially confounding variables. STUDY DESIGN: In a prospective longitudinal study, three cocaine exposure groups were defined by maternal report and infant meconium assay: unexposed, heavier cocaine exposure (>75th percentile self-reported days of use or of meconium benzoylecogonine concentration) or lighter cocaine exposure (all others). Neonatal ultrasounds from 241 well, term infants were read by a single radiologist who was masked to the exposure group. RESULTS: Infants with lighter cocaine exposure did not differ from the unexposed infants on any ultrasound findings. After controlling for infant gender, gestational age, and birth weight z scores and for maternal parity, blood pressure in labor, ethnicity, and use of cigarettes, alcohol, and marijuana during pregnancy, the more heavily cocaine-exposed infants were more likely than the unexposed infants to show subependymal hemorrhage in the caudothalamic groove (covariate adjusted odds ratio: 3.88; 95% confidence interval: 1.45, 10.35). CONCLUSIONS: This is the first study to demonstrate that ultrasound findings suggestive of vascular injury to the neonatal central nervous system are related to the level of prenatal cocaine exposure. Inconsistency in previous research in identifying an association between prenatal cocaine exposure and neonatal cranial ultrasound findings may reflect failure to consider dose effects. (+info)
Failure to pass meconium: diagnosing neonatal intestinal obstruction.
Timely passage of the first stool is a hallmark of the well-being of the newborn infant. Failure of a full-term newborn to pass meconium in the first 24 hours may signal intestinal obstruction. Lower intestinal obstruction may be associated with disorders such as Hirschsprung's disease, anorectal malformations, meconium plug syndrome, small left colon syndrome, hypoganglionosis, neuronal intestinal dysplasia and megacystis-microcolon-intestinal hypoperistalsis syndrome. Radiologic studies are usually required to make the diagnosis. In addition, specific tests such as pelvic magnetic resonance imaging, anorectal manometry and rectal biopsy are helpful in the evaluation of newborns with failure to pass meconium. (+info)
m-hydroxy benzoylecgonine recovery in fetal guinea pigs.
Recently, meta-hydroxybenzoylecgonine (m-OH BE) was identified by gas chromatography-mass spectroscopy during quantitative analysis for cocaine. Identification of m-OH BE in addition to the routinely identified benzoylecgonine by gas chromatography-mass spectroscopy confirmatory assays may increase detection of cocaine-exposed infants and decrease false negative results. However, it is not known whether m-OH BE is derived directly from benzoylecgonine or from hydroxylated cocaine, or whether this metabolite is produced in the fetus or transferred across the placenta from the maternal circulation. We quantitated the recovery of cocaine, benzoylecgonine, and m-OH BE from amniotic fluid, fetal meconium, fetal intestine, and maternal urine for up to 4 days after single dose administration of either cocaine or benzoylecgonine to pregnant time-bred guinea pigs. m-OH BE was recovered from meconium after maternal injections of cocaine and benzoylecgonine. There was no significant detection of m-OH BE from amniotic fluid or intestine and minimal recovery from maternal urine after either cocaine or benzoylecgonine administration. Detection of m-OH BE in meconium increased the identification of in utero exposed guinea pigs, and the greatest yield of m-OH BE from meconium occurred later than that observed for cocaine or benzoylecgonine. (+info)