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The number of red blood cells with nuclei in a brain-injured newborn's blood at birth may indicate when oxygen deprivation occurred. Researchers measured the number of nucleated red blood cells in the umbilical cord blood of 153 brain injured newborns and compared results with 83 healthy newborns. Newborns with fetal heart rate patterns indicating distress from the time of hospital admission, which suggests the problem was not labor related, averaged 49 nucleated red blood cells per 100 white blood cells versus 11 to 13 per 100 in newborns who developed distress patterns during labor and 3 in healthy newborns.

Byline: Lisa M. Korst (a)(b)(c)(d), Jeffrey P. Phelan (a)(b)(c)(d), Myoung Ock Ahn (a)(b)(c)(d), Gilbert I. Martin (a)(b)(c)(d) Abstract: Objective: Our goal was to update our experience with nucleated red blood cells as a marker for fetal asphyxia and to determine whether a relationship exists beteeen the presence of nucleated red blood cells and long-term neurologic impairment. Study Design: Nucleated red blood cell data from 153 singleton term neurologically impaired neonates were compared with cord blood nucleated red blood cells of 83 term nonasphyxiated newborns. Newborns with anemia, intrauterine growth restriction, and maternal diabetes were excluded. The group of neurologically impaired neonates was separated into the following subgroups: group I, persistent nonreactive fetal heart rate pattern from admission to delivery (n=69); group II, reactive fetal heart rate on admission followed by tachycardia with decelerations and absent variability (n=47); group III, reactive fetal heart rate on admission followed by an acute prolonged deceleration (n=37). The first and highest nucleated red blood cell value and the time of nucleated red blood cell disappearance were assessed. Results: The mean number of initial nucleated red blood cells was significantly higher in the group of neurologically impaired neonates (30.3[+ or -]77.5, range 0 to 732 per 100 white blood cells) than in the control group (3.4[+ or -]3.0, range 0 to 12 per 100 white blood cells) (p Conclusion: Our ongoing study indicates that nucleated red blood cells identify the presence of fetal asphyxia. When fetal asphyxia is present, distinct nucleated red blood cell patterns are observed that relate to the timing of fetal injury. In general, intrapartum injuries are associated with lower nucleated red blood cell values. Thus our data continue to support the concept that nucleated red blood cell levels may assist in determining the timing of fetal neurologic injury. Author Affiliation: (a) Department of Obstetrics and Gynecology, The Perinatal Center, Pomona Valley Hospital Medical Center Pasadena USA (b) Department of Obstetrics and Gynecology, Cha Women's Hospital of Seoul Seoul, Korea USA (c) Department of Neonatology, Queen of the Valley Hospital Pomona, West Covina USA (d) Department of Pediatrics, University of California, Irvine, School of Medicine Orange, California USA Article Note: (footnote) * Presented at the Sixteenth Annual Meeting of the Society of Perinatal Obstetricians, Kamuela, Hawaii, February 4-10, 1996.

The nucleated red blood cell count may indicate whether a fetus has experienced a lack of oxygen, and may predict whether a newborn will experience neurologic impairment throughout its life. Researchers compared nucleated red blood cell counts from 46 newborns with neurologic impairment to those of 83 normal newborns who did not experience a lack of oxygen. Normal newborns had nucleated red blood cell counts of 12 or less, while neurologically impaired newborns had an average count of 34.5. Nucleated red blood cell counts were higher when the lack of oxygen occurred earlier in the pregnancy than when the lack of oxygen was closer to birth. The rate at which nucleated red blood cells disappear after birth may indicate the type of event causing lack of oxygen.

The majority of neurologically impaired infants born at term suffered the damage to their central nervous systems during pregnancy. Thus, labor management had no effect. An analysis of the records, including the electronic fetal monitor tracings, of 48 neurologically impaired newborn infants found that 33 (69%) had a nonreactive fetal heart rate (FHR) pattern at the time of hospital admission. This suggests injury from asphyxia, lack of oxygen. These infants were also more likely to have other symptoms of prenatal distress or injury: thick 'old' meconium (fetal fecal matter), meconium-stained skin, and meconium aspiration syndrome. There was little evidence of overly strong uterine contractions during the ensuing labor. By contrast, the 15 (31%) of infants who had reactive FHRs on admission developed a typical asphyxial pattern in labor: rapid heart rate, nonreactivity, diminished variability and decelerations in reaction to conditions. Oxytocin use to stimulate contractions was more likely as were episodes of overly strong contractions.

The well-being of a fetus can be assessed by measuring the response of the fetus to noise (acoustic stimulation) and to contraction-induced stress tests. In both techniques, the fetus responds to the stimulus by altering its heart rate. Abnormal fetal heart rate patterns can predict abnormal fetal conditions. The benefit of continuous electronic fetal monitoring over listening to fetal heart rate intermittently (intermittent fetal auscultation) has not been clearly demonstrated. A method of predicting which fetuses are not likely to tolerate a stressful labor would be beneficial. The usefulness of fetal acoustic stimulation in predicting future fetal conditions was evaluated for 201 patients. All women had cervical dilation of at least four centimeters and were carrying a single fetus. One or more complications of pregnancy was present in 118 patients (60 percent). Acoustic stimulation was applied using a stimulator placed on the mother's abdomen. Fetal heart rate acceleration of at least 15 beats per minute over the baseline for 15 seconds was considered reactive. Lack of accelerated fetal heart rate after three stimulations was considered nonreactive. Of the 201 fetuses receiving acoustic stimulation, 14 (7 percent) were nonreactive. A nonreactive response was associated with future fetal complications. There was no difference in the fetal complication rate of fetuses with pure reactive responses and the 25 percent of the fetuses who experienced a transient fetal heart rate decrease after stimulation. Therefore, acoustic stimulation of a fetus early in labor is useful in isolating fetuses likely to develop a complication. (Consumer Summary produced by Reliance Medical Information, Inc.)

Fetal distress can be identified by abnormal fetal heart rate patterns. During labor, periodic fetal heart rate assessments are as effective as continuous electronic fetal heart rate monitoring in assessing fetal distress. A test performed at hospital admission would be helpful in identifying the current condition of the fetus and the likelihood of distress. Patients could then be classified with either low or high risk status. Methods for determining the possibility of fetal distress include nonstress testing, initial fetal heart monitoring strips, and assessments of fluid surrounding the fetus (amniotic fluid) and blood flow inside the umbilical artery. The flow of blood through the umbilical artery was determined by Doppler ultrasonography, the use of high frequency sound to determine the behavior of moving structures. The value of these methods in predicting subsequent fetal distress was studied. In the 109 patients evaluated, fetal heart rate patterns and the amount of amniotic fluid were the best predictors of potential fetal distress. Doppler velocimetry during labor was not useful as a predictive tool when used alone. Initial fetal heart tracings and the measurement of amniotic fluid can be used as an admissions test to facilitate the management of patients in labor. (Consumer Summary produced by Reliance Medical Information, Inc.)

Women who have had a prior cesarean sections (delivery of an infant by abdominal incision) commonly have repeat cesarean in subsequent pregnancies because the possibility of separation of previous surgical incisions (dehiscence) is generally considered too great. Dehiscence actually only occurs in 2 percent of single fetus pregnancies. Vaginal delivery after cesarean section now is much more widely accepted and trial labors, induced in order to observe the likelihood of vaginal delivery being successful, are now considered safe in single fetus pregnancies. The safety in twin pregnancies is unknown. Cesarean sections involve many risks, including maternal infections and surgical complications, which may even cause the death of the mother. Pregnancy outcomes of 56 women with twin pregnancies who had had previous cesarean deliveries were evaluated. Of these, 25 patients were selected for vaginal delivery, and 18 delivered both twins successfully. The dehiscence rate was 4 percent, and there were no differences in morbidity and mortality rates between trial labor and non-trial labor groups. Following usual safeguards recommended for a twin delivery, vaginal delivery after cesarean can be attempted in carefully selected patients.

The onset of seizures after birth has been considered evidence of an intrapartum asphyxial event. The present study was undertaken to determine whether the timing of neonatal seizures after birth [...]