Biophysical profile with amniotic fluid volume assessments. Amniotic fluid index vs single deepest pocket technique during modified biophysical profile: a randomized clinical trial. A randomized clinical trial of the intrapartum assessment of amniotic fluid volume: amniotic fluid index versus the single deepest pocket technique. A randomised comparison between amniotic fluid index and maximum pool depth in the monitoring of post-term pregnancy. A randomised controlled trial of simple compared with complex antenatal fetal monitoring after 42 weeks of gestation. A randomized study to assess the efficacy of the amniotic fluid index as a fetal admission test. Effect of early amniotomy on the risk of dystocia in nulliparous women. The Canadian Early Amniotomy Study Group. Transabdominal amnioinfusion in oligohydramnios at term before induction of labor with intact membranes: a randomized clinical trial. Prophylactic transcervical amnioinfusion in laboring women with oligohydramnios.
To compare the amniotic fluid index (AFI) with the single deepest pocket technique along with the other components of the biophysical profile (BPP) in predicting an adverse pregnancy outcome.
                Prospective, randomized trial of amniotic fluid assessment by AFI or single deepest pocket during a BPP. Cesarean delivery for fetal distress was the primary outcome evaluated.
                The AFI was used in 273 pregnancies and the single deepest pocket in 264. The AFI significantly increased the number of pregnancies labeled as oligohydramnios, 102 women (38%) compared with 46 women (17%; P <.001), odds ratio (OR) = 2.84, 95% confidence interval 1.90-4.25 in the single deepest pocket group. There was no difference in the number of women with oligohydramnios in the AFI group, 16 of 102 (16%), undergoing a cesarean delivery for fetal intolerance of labor compared with the single deepest pocket group, 6 of 46 (13%; P =.676). More women with normal fluid by the AFI method (AFI > 5), 20 of 170 (12%), underwent a cesarean delivery for fetal distress than the women with normal fluid by the single deepest pocket technique (2 cm x 1 cm pocket present) group, 12 of 218 (6%; P =.037, OR = 2.22, 95% confidence interval 1.05-4.70).
                The AFI offers no advantage in detecting adverse outcomes compared with the single deepest pocket when performed with the BPP. The AFI may cause more interventions by labeling twice as many at-risk pregnancies as having oligohydramnios than with the single deepest pocket technique. The purpose of this study was to determine the superior technique, if either, of the amniotic fluid index (AFI) vs the single deepest pocket technique in predicting an adverse pregnancy outcome among high-risk patients undergoing antenatal testing.
                Patients having modified biophysical profile (nonstress test plus sonographic estimation of amniotic fluid) were randomized to either have AFI or determination of the presence or absence of a 2 x 1-cm single deepest pocket.
                Between January of 1997 and December of 2001, 1080 women were randomized with 530 women in the AFI arm, and 558 in the 2 x 1 pocket arm. The maternal demographics and prenatal complications were similar between groups. Significantly more patients were identified as having oligohydramnios using AFI (17%) compared with using 2 x 1 pocket (10%) ( P =.002). The overall rate of cesarean section for nonreassuring fetal heart rate (FHR) tracing was 3.8% (30 cases, with 16 cases in the AFI-monitored, and 14 cases in the 2 x 1 pocket-monitored groups, respectively, P =.608). Logistic regression analysis showed no difference between the groups with respect to the ability to identify patients who underwent cesarean section for nonreassuring FHR tracing during labor ( P =.999). The umbilical artery pH <7.1 ( P =.688) and admission to the newborn intensive care unit were also comparable between groups.
                During antepartum fetal surveillance, use of single deepest pocket compared with amniotic fluid index is associated with a significantly lower rate of suspected oligohydramnios. The purpose of this study was to determine whether an intrapartum assessment of amniotic fluid identifies a pregnancy that is at risk for an adverse outcome.
                Parturients who were admitted for delivery were assigned randomly to have the amniotic fluid assessed either by amniotic fluid index or by the presence of a 2 x 1 pocket.
                The amniotic fluid index was obtained in 499 pregnancies, and the 2 x 1 technique was performed in 501. Oligohydramnios was diagnosed in 25% of amniotic fluid index pregnancies versus 8% with the use of the 2 x 1 pocket technique (P <.001). Both techniques failed to identify patients who underwent an amnioinfusion for fetal distress (P=.864) or who experienced variable (P=.208) or late decelerations (P=.210) that influenced delivery, fetal distress in labor (P=.220), caesarean delivery for fetal distress (P=.133), and admission to neonatal intensive care unit (P=.686).
                Neither the amniotic fluid index nor the 2 x 1 pocket technique that was undertaken as a fetal admission test identifies a pregnancy that is at risk for an adverse outcome. To compare the impact of two different ultrasound methods for assessing amniotic fluid volume on the incidence of obstetric interventions in post-term pregnancies.
                A prospective randomised controlled trial.
                Liverpool Women's Hospital.
                Five hundred women with singleton, uncomplicated pregnancies with gestational age > or = 290 days.
                Random allocation to fetal monitoring by either: 1. amniotic fluid index and computerised cardiotocography, or 2. maximum pool depth and computerised cardiotocography.
                Primary: caesarean section. Secondary: the number of abnormal monitoring tests, induction of labour, intrapartum management and neonatal outcome.
                The number of abnormal amniotic fluid indices was significantly higher than the number of abnormal maximum pool depths (10% vs 2.4%; OR 4.51, 95% CI 1.82-11.21; P = 0.0008) which resulted in more inductions for abnormal post-term monitoring in the amniotic fluid index group (14.8% vs 8.4%; OR 1.89; 95% CI 1.07-3.33; P = 0.0362) and more intrapartum electronic fetal monitoring (94.4% vs 88.4%; OR 2.21; 95% CI 1.13-4.29; P = 0.0255). There were no other statistically significant differences in outcomes related to labour and delivery, but there was a trend towards more caesarean sections in the amniotic fluid index group (18.8% vs 13.2%), in particular caesarean sections for fetal distress (8% vs 4%). There were no perinatal deaths and no statistically significant differences in perinatal outcome between the two groups.
                Published reference ranges for amniotic fluid index overestimate the number of abnormal results in post-term pregnancies. Their use, when compared with maximum pool depth, is likely to increase the number of obstetric interventions with, as yet, an uncertain impact on perinatal mortality and morbidity. It is possible that antepartum fetal assessment in pregnancies where the risk of adverse perinatal outcome is very low may cause, rather than prevent morbidity. To compare the impact on perinatal outcome of two different protocols for antenatal fetal monitoring after 42 weeks gestation.
                A prospective randomised controlled trial.
                Liverpool Maternity Hospital.
                One hundred and forty-five women with singleton, uncomplicated pregnancies after 42 weeks of gestation.
                Random allocation to fetal monitoring by either: 1. a modified biophysical profile comprising of computerised cardiotocography, amniotic fluid index, and assessment of fetal breathing, tone and gross body movements; or 2. standard cardiotocography and maximum pool depth.
                Cord pH at delivery, number of abnormal monitoring tests, intrapartum management, mode of delivery and neonatal outcome.
                There were significantly more abnormal antenatal monitoring results in the modified biophysical profile group (47.2% vs 20.5%; odds ratio = 3.5, 99% CI = 1.3-9.1). There were no differences in cord blood gases, neonatal outcome, or in outcomes related to labour and delivery between the two groups, but a trend towards more obstetric interventions in the modified biophysical profile group was noted. Amniotic fluid volume after 42 weeks was more likely to be labelled as abnormal with amniotic fluid index than with maximum pool depth (44.4% vs 15.1%; odds ratio = 4.5, 99% CI = 1.6-12.8).
                The results suggest that after 42 weeks fetal monitoring with the modified biophysical profile does not improve pregnancy outcome as measured by umbilical cord pH, but is more likely to yield an abnormal result. The higher incidence of abnormal monitoring results in the modified biophysical profile group was likely to be caused by different methods of amniotic fluid assessment in the modified biophysical profile group (amniotic fluid index) and simple monitoring group (maximum pool depth). The use of amniotic fluid index as a test of fetal wellbeing in prolonged pregnancy may lead to more obstetric interventions with, as yet, unclear impact on the perinatal outcome. To determine whether there is a difference in the incidence of abdominal delivery for presumed fetal distress in women who have an intrapartum fluid index assessment and those who do not.
                Over a 7-month period, parturients at 26-42 weeks' gestation and in early labor were randomized to the study (measured amniotic fluid index [AFI] on admission) or a control group (no sonographic assessment of amniotic fluid [AF] volume). The labor and delivery staff were aware of the AFI results of the study subjects. All patients had continuous electronic fetal monitoring, and none had an abnormal tracing on admission. Student t test or chi 2 was used for statistical analysis. P < .05 was considered significant.
                The study (N = 447) and control groups (N = 436) had similar maternal demographics as well as medical and obstetric complications. In the study group, the incidence of abdominal delivery for fetal distress (29 of 447) was significantly higher than among controls (14 of 436) (P = .02; relative risk 1.3, 95% confidence interval 1.1-1.7). Among parturients who had abdominal delivery for fetal distress, the decision-to-incision times (mean +/- standard deviation) were similar for parturients who had undergone assessment of AFI and those who had not (38.5 +/- 14.7 versus 32.5 +/- 14.7 minutes, respectively; P = .47). Mean birth weight, incidence of low birth weight, macrosomia, Apgar scores less than 7, and the number of admissions to the neonatal intensive care unit were not significantly different in the two groups.
                Patients having an intrapartum assessment of AFI as a fetal admission test are significantly more likely to have abdominal delivery for presumed fetal distress. However, the decision-to-incision time is not decreased and the perinatal outcome is not improved if the status of AF volume is known for patients in early labor. Early amniotomy has been advocated as a means of preventing dystocia, but its efficacy has not been studied prospectively. The purpose of this multicenter study was to determine whether routine early amniotomy reduces the risk of dystocia for nulliparous women in spontaneous labor.
                We studied 925 nulliparous women in labor, who were stratified according to the degree of cervical dilatation (< 3 cm vs. > or = 3 cm) and randomly assigned to either early rupture of the membranes (amniotomy group) or conservative management of labor (conservative-management group). Dystocia was defined as a period of at least four hours after dilatation of the cervix to 3 cm had been reached during which the mean rate of cervical dilatation was less than 0.5 cm per hour.
                Dystocia was significantly less frequent in the amniotomy group than in the conservative-management group (34 percent vs. 45 percent; relative risk, 0.8; 95 percent confidence interval, 0.6 to 0.9). The median length of time from randomization to full dilatation was 136 minutes shorter in the amniotomy group, and there was a trend toward less frequent use of oxytocin among the women assigned to amniotomy (36 percent vs. 41 percent; relative risk, 0.9; 95 percent confidence interval, 0.8 to 1.0). In a stratified analysis, the frequency of dystocia associated with amniotomy was reduced only among women with > or = 3 cm initial dilatation. The cesarean-section rate was similar in the two groups (amniotomy, 12 percent; conservative management, 11 percent). There were no statistically significant differences in outcome between the infants delivered by the women in the two groups; the measures of an adverse outcome included admission to a neonatal intensive care unit, five-minute Apgar score below 7, and arterial cord-blood pH below 7.2.
                Early amniotomy is an effective method of shortening the duration of labor and reducing the frequency of dystocia among nulliparous women in labor, but it does not lower the rate of cesarean section. Our purpose was to determine the effectiveness of transabdominal amnioinfusion before induction of labor in reducing the incidence of fetal distress in pregnancies with oligohydramnios at term.
                Between June 1991 and September 1994 primiparous women with ultrasonographic evidence of oligohydramnios at term, intact membranes, and unripe cervix (Bishop score < or = 6), candidates for induction of labor with cervical or vaginal prostaglandin E2 gel, were randomly selected to receive transabdominal amnioinfusion (amnioinfused group, n = 39) or to proceed with direct labor induction (control group, n = 40). Inclusion criteria were (1) singleton gestation, (2) vertex presentation, (3) ultrasonographic estimation of fetal weight > or = 2500 gm, and (4) reactive nonstress test. Fetoneonatal outcome variables were compared between the two groups. Statistical analysis used contingency tables, Student t test, or Wilcoxon rank-sum tests, where applicable.
                Amnioinfusion was successfully performed in 100% of the patients randomized for the procedure. The incidence of severely abnormal fetal heart rate tracings was significantly higher in the control than in the amnioinfused group (42% [17/33] vs 5% [2/37], relative risk 12.9, 95% confidence interval 2.4 to 56.4). The rate of cesarean sections performed for fetal distress was fivefold higher in the control group (25% [10/40] vs 5% [2/39], relative risk 4.9, 95% confidence interval 1.1 to 32.4). No bleeding complications or fetomaternal infectious morbidity were noticed.
                Transabdominal amnioinfusion is a safe, effective option for the prevention of fetal distress in pregnancies with oligohydramnios at term with intact membranes and unripe cervix. Evaluation of prophylactic intrapartum amnioinfusion in women with oligohydramnios.
                Assiut University Hospital during the period from February 2000 to September 2001, 160 laboring women with oligohydramnios [amniotic fluid index (AFI) </=5 cm] were randomized into: amnioinfusion and control groups. Inclusion criteria were: term singleton gestation, vertex presentation, cervical dilatation <4 cm, and assuring fetal heart rate (FHR). Trans-cervical amnioinfusion was done with warmed normal saline.
                there was a significant increase in AFI after amnioinfusion (P<0.001). The amnioinfusion group showed lower cesarean section rate for fetal distress (P=0.003), lower incidence of abnormal FHR (P=0.006), fewer neonates with Apgar score <7 at 1 min (P<0.001), and 5 min (P=0.009), meconium below vocal cords (P<0.001), umbilical arterial pH<7.1 (P=0.003), and significantly shorter hospital stay (P=0.02).
                Prophylactic trans-cervical amnioinfusion is a simple, safe and effective procedure.
The single deepest vertical pocket measurement in the assessment of amniotic fluid volume during fetal surveillance seems a better choice since the use of the amniotic fluid index increases the rate of diagnosis of oligohydramnios and the rate of induction of labor without improvement in peripartum outcomes. A systematic review of the diagnostic accuracy of both methods in detecting decreased amniotic fluid volume is required.