Long-term intravenous tocolytic therapy.

Eighteen women required continuous intravenous tocolytic therapy with either ritodrine hydrochloride or magnesium sulfate for greater than 48 hours because of repetitively recurrent preterm labor; these were compared with a similar group of women successfully treated in less than 48 hours in a retrospective, case-controlled study. The mean gestational age at the time of diagnosis was 31 weeks for both groups. Tocolytic selection was similar in both groups, although the dosage per hour was significantly greater with long-term therapy. The mean interval from initiation of therapy until delivery was 41 days in the study group, compared with 39 days among controls (not statistically significant). The mean gestational age at delivery was 36 weeks in both groups. There were no significant difference in various measures of fetal outcome between groups. These data demonstrate that long-term intravenous tocolytic therapy can be a safe and effective means of prolonging gestation in those women who fail to respond to conventional treatment.

Transabdominal amnioinfusion in preterm pregnancies complicated by fetal growth restriction, oligohydramnios and umbilical cord compression.

Fetal growth restriction with oligohydramnios occurring in the preterm gestation is associated with significant fetal morbidity and mortality. We investigated the possibility that transabdominal amnioinfusion might relieve acute cord compression and allow prolongation of gestation long enough to administer corticosteroids. Four patients with fetal growth restriction, oligohydramnios and evidence of significant cord compression with otherwise reassuring fetal heart rate testing underwent transabdominal amnioinfusion. Pregnancy was prolonged 22, 38, 10 and 9 days, and cord compression was relieved in all cases. One patient showed findings consistent with reversal of chronic hypoxemia with stabilization of amniotic fluid index measurements in the normal range and normalization of fetal growth. Transabdominal amnioinfusion may be useful as an adjunctive technique to prolong pregnancy in preterm gestations with fetal growth restriction, oligohydramnios and evidence of umbilical cord compression.

Risk factors for preterm delivery in a healthy cohort.

To examine whether risk factors differed among subgroups of preterm (< 37 weeks of gestation) deliveries, we studied a cohort of 1,825 enlisted servicewomen who delivered from 1987 through 1990 at four U.S. Army medical centers. Preterm deliveries were classified by length of gestation (< 29 weeks, 29-32 weeks, 33-36 weeks) and clinical course [medical indication, idiopathic preterm labor, or preterm rupture of membranes (PROM)]. We abstracted medical records for information on age, race, army rank, marital status, gravidity, parity, the baby's sex, maternal prepregnancy height and weight, gestation at entry to prenatal care, alcohol drinking and smoking, time since and outcome of preceding pregnancy, surgery performed during pregnancy, anemia, and diagnoses of uterine abnormalities, sexually transmitted diseases, and urinary tract infections. We used proportional hazards analysis to evaluate associations for each subgroup of preterm delivery. The relative odds associated with a history of preterm delivery in the preceding pregnancy ranged from 3.1 for deliveries due to preterm labor or PROM to 6.2 for deliveries that occurred during 29-32 weeks; none of the other factors was consistently associated across the subgroups of preterm delivery. The paucity of associations is consistent with the conclusion of other investigators that most of the causes of preterm delivery are unknown.

Antenatal hospitalization among enlisted servicewomen, 1987-1990.

OBJECTIVE: To describe the prevalence of, and indications for, antenatal hospitalization among women who delivered live and stillborn infants. METHODS: We reviewed the records of a cohort of 1825 black and white enlisted women who delivered from 1987-1990 at the four largest Army medical centers in the United States. Women with multiple gestations and those whose pregnancies ended before 20 weeks' gestation were excluded. Records of all women with preterm deliveries and a one-third sample of women with term deliveries were abstracted. RESULTS: Overall, 26.8 +/- 1.6% (mean +/- standard error) of the women were hospitalized antenatally. Of the estimated 702 antenatal hospitalizations, 44.0 +/- 3.4% were related to preterm labor, 10.3 +/- 1.9% to preeclampsia, 5.5 +/- 1.5% to hyperemesis, and 4.7 +/- 1.5% to urinary tract or kidney infection. The prevalence of hospitalization was lowest before 20 weeks (5.0 +/- 0.8%) and highest at 33-36 weeks (12.2 +/- 1.2%). Small and probably clinically insignificant differences between black and white women were noted in the overall prevalence of antenatal hospitalization and in the indications for hospitalization. CONCLUSION: As measured by hospitalization, severe antenatal morbidity is common in this population of healthy enlisted women.

Fetal choroid plexus cysts in association with cri du chat (5p-) syndrome.

The significance of fetal choroid plexus cysts is controversial. We report a case of antenatally detected cri du chat syndrome (5p-) in one fetus of a twin pregnancy in association with bilateral fetal choroid plexus cysts and unassociated with other structural malformations. Choroid plexus cysts may be nonspecific markers for chromosomal anomalies.

Partial molar pregnancy with fetal survival: an unusual example of confined placental mosaicism.

BACKGROUND: A pregnancy with a partial molar placenta and a normal fetus is a rare condition. Few guidelines exist for antenatal evaluation and management, particularly with respect to selecting cases for conservative management. CASE: Cytogenetic analysis of chorionic villi showed a triploid placenta, and both amniotic fluid and blood indicated a diploid fetus. The pregnancy resulted in a normal newborn. CONCLUSION: This disorder appears to be due to confined placental mosaicism.

Intraobserver and interobserver variability of the amniotic fluid index.

OBJECTIVE: We assessed intraobserver and interobserver variations in the performance of the amniotic fluid index. STUDY DESIGN: A total of 34 women in the third trimester with intact membranes were examined twice by each of three examiners. The amniotic fluid index was measured once by each of the three examiners in order, then repeated by each examiner in the same order. Numeric displays on the video terminal screen were covered so that the examiners were blinded to actual measurement values. Results were recorded on hard copy for later data analysis. A senior investigator supervised all examinations to monitor consistency of technique. RESULTS: Overall, the coefficient of variation for amniotic fluid index measurements varied from 10.8% within examiners to 15.4% between examiners. Both between and within variation of absolute differences increased as the amniotic fluid index value increased, while the percent difference decreased. Simply repeating the test by the same examiner will decrease the coefficient of variation significantly. CONCLUSION: Although intraobserver and interobserver variability cannot be eliminated, its impact can be minimized by use of the same examiner for serial studies.

Preterm delivery among black and white enlisted women in the United States Army.

OBJECTIVE: To examine black-white differences in preterm delivery in a healthy population who had unrestricted access to prenatal care. METHODS: We conducted a retrospective cohort study of 842 black and 1026 white enlisted servicewomen who delivered a singleton infant of 20 or more weeks' gestation from July 1, 1987 through September 30, 1990 at four Army Medical Centers in the United States. Data were collected by reviewing maternal and newborn records. We used logistic and proportional hazards regression models to analyze outcomes defined by length of gestation, cause of preterm delivery, and jointly by length and cause. RESULTS: Black enlisted women had a cumulative probability of preterm delivery (13.5%) that was higher than that for white enlisted women (10.5%) (hazard ratio 1.31, 95% confidence interval [CI] 1.002-1.70). However, the ratio of black-to-white hazards was not uniform. Black-white differences were small and nonsignificant from 33-36 weeks' gestation, when most preterm deliveries occur. The differences were also small and nonsignificant for deliveries related to spontaneous rupture of membranes or idiopathic preterm labor, the most common causes of preterm delivery. The black-to-white hazard ratios were greatest for all deliveries before 33 weeks' gestation and for medically indicated preterm deliveries. CONCLUSIONS: Efforts to reduce black-white differences in preterm delivery must go beyond providing prenatal care and eliminating recreational drug use. Future studies should consider black-white differences in environments during the mother's own development and in psychosocial and physical stresses during pregnancy.

Significance of intrapartum amniotic fluid volume in the presence of nuchal cords.

Among 70 women delivering infants with nuchal cords, there was a significantly higher incidence of meconium passage and severe variable fetal heart rate decelerations/fetal bradycardia in those who had intrapartum oligohydramnios, as defined by an amniotic fluid index less than or equal to 5.0 cm. Oligohydramnios in the presence of nuchal cord entanglement might represent an increased risk of ominous intrapartum fetal heart rate patterns.

Coronal transcerebellar diameter: an alternate view.

Evaluation of the fetal cerebellum in the axial plane has become an important part of obstetric sonography. We report our experience with an alternate view, the coronal transcerebellar view, in 134 fetuses at gestational ages of 13-30 weeks. There is a linear first-order correlation between axial and coronal transcerebellar diameters. Additionally, the coronal view was more reliably obtained, especially at gestational ages between 24 and 30 weeks. We believe that this view warrants further study, particularly in pathological states.

The significance of amniotic fluid volume during intrapartum fetal acoustic stimulation.

The relationship of intrapartum fluid volume to the fetal response to acoustic stimulation was investigated in 112 patients who were in the latent phase of labor. Amniotic fluid volume appears to play an insignificant role in the genesis of fetal heart rate decelerations that occur after fetal acoustic stimulation, regardless of the amount of amniotic fluid present.

Fetal macrosomia in a military hospital: incidence, risk factors, and outcome.

The purpose of this paper is to determine the incidence of fetal macrosomia, analyze risk factors, and review maternal and fetal outcome. Macrosomia occurred in 15.1% of deliveries, with very macrosomic fetuses comprising 4.1% of these pregnancies; 61.3% were male. Diabetes mellitus, post-term pregnancy, and excessive weight gain were identified as maternal risk factors. The incidence of shoulder dystocia, birth injury, and low Apgar scores was significantly higher than in controls. In addition, cesarean section rates were higher for the macrosomic groups. Fetuses delivered vaginally had more frequent birth injury than those delivered by cesarean section. Women at risk for fetal macrosomia should be screened, and liberal use of cesarean section is recommended.

Congenital chyloperitoneum as a cause of isolated fetal ascites.

Isolated fetal ascites is an unusual prenatal finding and must be differentiated from immune and nonimmune hydrops. This entity is most commonly associated with gastrointestinal and genitourinary anomalies. Fetal chyloperitoneum, however, should be considered as a possible cause. Pulmonary hypoplasia and abdominal dystocia during attempted vaginal delivery are potential complications. We present a case of isolated fetal ascites due to congenital chyloperitoneum.

Fetal acoustic stimulation as a possible adjunct to diagnostic obstetric ultrasound: a preliminary report.

Unfavorable fetal position during diagnostic obstetric ultrasound can interfere with visualization of certain structures, leading to prolonged or repeated examination. Fetal acoustic stimulation induces a fetal startle reflex and an increase in fetal movements. This report describes our experience with fetal acoustic stimulation to prompt fetal movement in an effort to improve fetal visualization. At gestational ages of 28 weeks or more a 94.1% success rate was noted, in 30 seconds or less in 70.6% of the cases. We conclude that fetal acoustic stimulation may be a valuable adjunct to diagnostic obstetric ultrasound.

Intrapartum amniotic fluid volume at term. Association of ruptured membranes, oligohydramnios and increased fetal risk.

The amniotic fluid index (AFI), a semiquantitative technique for assessing amniotic fluid volume, has been shown to be a useful adjunct in antepartum surveillance. We evaluated the usefulness of the AFI in the early intrapartum period as it relates to subsequent fetal morbidity and fetal heart rate patterns. Two hundred term gravidas presenting in the latent phase of labor with vertex-presenting fetuses were studied. An intrapartum AFI less than or equal to 5.0 cm was associated with a significant increase in the risk of cesarean section for fetal distress and of an Apgar score of less than 7 at one minute as well as abnormal fetal heart rate patterns in late labor. The majority (71.4%) of the patients with an intrapartum AFI less than or equal to 5.0 cm had ruptured membranes on entry; however, there was no significant difference in outcome when they were compared to patients with intact membranes and oligohydramnios. Variable decelerations on entry were associated with oligohydramnios in 43.8% of the patients. An AFI less than or equal to 5.0 cm in the early intrapartum period is a risk factor for perinatal morbidity and abnormal fetal heart rate patterns in subsequent labor, and ruptured membranes in early labor are a risk factor for oligohydramnios.

Prophylactic intrapartum amnioinfusion: a randomized clinical trial.

Amnioinfusion was performed in a prospective, randomized trial of 60 women in the latent phase of labor with oligohydramnios, as defined by an amniotic fluid index less than or equal to 5.0 cm. All fetuses were at least 37 weeks' gestational age, had normal baseline fetal heart rate variability, and no clinically significant fetal heart rate decelerations at the outset. Subjects in the amnioinfusion group (n = 30) were titrated to and maintained at an amniotic fluid index level greater than or equal to 8.0 cm throughout labor. In the group receiving amnioinfusion, significantly lower rates of meconium passage (p = 0.04), severe variable decelerations (p = 0.04), end-stage bradycardia (p = 0.05), and operative delivery for fetal distress (p = 0.002) occurred. Significantly higher umbilical arterial blood pH values were also noted in the infusion group (p = 0.02). We conclude that prophylactic intrapartum amnioinfusion is an important technique for the reduction of intrapartum morbidity.

Relationship of early intrapartum fetal heart rate patterns to subsequent patterns and fetal outcome.

This study evaluated subsequent fetal heart rate (FHR) patterns and fetal outcome in laboring women with normal or abnormal initial FHR patterns. Four hundred term gravidas presenting in the latent phase of labor were studied. Ninety (22.5%) exhibited abnormalities on the initial tracing, with the majority of those abnormalities (58.9%) including mild variable decelerations, either alone or in combination with other abnormalities. An analysis of the outcome for those patients revealed a significant increase in cesarean delivery for fetal distress and depressed one-minute Apgar scores when compared to patients with initially normal tracings. Analysis of subsequent FHR patterns in that group showed a significant increase in the incidence of atypical variable declerations and bradycardia. Patients with more than one abnormality on the initial FHR tracing showed a greater incidence of loss of variability, loss of reactivity and bradycardia on subsequent FHR tracings. Likewise, pregnancy outcome for this group was remarkable for an increased risk of meconium staining, cesarean delivery for fetal distress and depressed one-minute Apgar scores. An abnormal initial FHR tracing seems to be associated with the subsequent development of ominous FHR patterns and increased fetal morbidity, particularly when more than one abnormality is present on the initial tracing.

Fetal acoustic stimulation in the early intrapartum period as a predictor of subsequent fetal condition.

Fetal acoustic stimulation has recently received much attention in the literature. This study evaluates fetal acoustic stimulation in the early intrapartum period as a predictor of subsequent fetal condition. The study group consisted of 201 patients, approximately 60% of whom had complicated pregnancies. All were in the latent phase of labor with singleton, vertex-presenting fetuses. Gestational age ranged from 37 to 43 weeks. Fourteen of the 201 fetuses (7%) showed a nonreactive response to fetal acoustic stimulation and those fetuses were at significantly greater risk of initial and subsequent abnormal fetal heart rate patterns, meconium staining, and cesarean delivery because of fetal distress and Apgar scores less than 7 at both 1 and 5 minutes. Transient fetal heart rate decelerations after a reactive response occurred in 25% of patients; however, fetal outcome was not worse in this group. A reactive response to fetal acoustic stimulation was associated with high specificity and negative predictive values. Therefore we conclude that fetal acoustic stimulation in the early intraprtum period may discriminate the compromised from the noncompromised fetus.

Intrapartum Doppler velocimetry, amniotic fluid volume, and fetal heart rate as predictors of subsequent fetal distress. I. An initial report.

This study examines the usefulness of umbilical artery Doppler velocimetry, amniotic fluid volume assessment, and fetal heart rate data in the early intrapartum period as predictors of subsequent fetal distress. A total of 109 patients seen in the latent phase of labor in the labor and delivery area were studied. Both an abnormal initial fetal heart rate and an amniotic fluid index less than or equal to 5.0 cm were associated with a significant increase in the incidence of intrapartum fetal distress. Conversely, a systolic/diastolic ratio greater than 3.0 by Doppler ultrasonography was not associated with increased fetal morbidity. Overall, the sensitivities, specificities, and positive predictive values of the fetal heart rate tracing and the amniotic fluid volume assessment were comparable. Doppler systolic/diastolic ratios showed very poor sensitivity and positive predictive value. We conclude that the fetal heart rate tracing or the assessment of amniotic fluid volume in the early intrapartum period are reasonable predictors of subsequent fetal condition. The lack of patients with the absence of or reverse umbilical velocity preclude conclusions with regard to Doppler systolic/diastolic ratios for this purpose.