Subjective versus objective evaluation of amniotic fluid volume of pregnancies of less than 24 weeks' gestation: how can we be accurate?

This study was undertaken to compare subjective versus objective ultrasonic evaluation of amniotic fluid volume in pregnancies of less than 24 weeks' gestation. Amniotic fluid volume was subjectively (visualization without ultrasonic measurements) and objectively (visual interpretation with ultrasonic measurements) evaluated in 42 singleton pregnancies undergoing termination. The actual amniotic fluid volume was then determined using a dye-dilution technique. The women evaluated were in their mid-20s, primarily African American, and between 15 and 23 weeks' gestation. There was no significant difference in the total number of correct estimates of amniotic fluid volume when the data were stratified by level of operator experience (P = .34), ultrasonic technique (P = .33), or the combined correct subjective versus combined correct objective estimates (P = .68). We have concluded that the accuracy of amniotic fluid volume assessment in pregnancies of less than 24 weeks is not influenced by the level of operator experience or the type of ultrasonic measurement.

Change in platelet count predicts eventual maternal outcome with syndrome of hemolysis, elevated liver enzymes and low platelet count

OBJECTIVE

To profile the rates of change for platelets and lactate dehydrogenase (LDH) in patients with the syndrome of hemolysis, elevated liver enzymes and low platelet count (HELLP) to reflect and possibly predict disease severity.

METHODS

Serial determinations of the platelet count and serum LDH were analyzed retrospectively for 545 patients with HELLP syndrome and 94 severely pre-eclamptic patients. A repeated measures (mixed model) analysis of variance (ANOVA) was utilized to estimate the rates of change for LDH and platelets in each group.

RESULTS

Patients who developed class 1 or 2 HELLP syndrome exhibited a rapid deterioration in platelet count of 45-50,000/microl per day compared to 30,000/microl per day for class 3 and non-HELLP severe pre-eclampsia. For LDH, values increased at a rate of approximately 1400 IU/l per day, 600 IU/l per day, 300 IU/l per day and 200 IU/l per day for patients with classes 1, 2 and 3 and for non-HELLP severe pre-eclampsia, respectively.

CONCLUSION

The rate of change of platelets and LDH appeared to correlate well with eventual syndrome severity and this can be used to enhance patient assessment beyond the value of a single test for either laboratory parameter.

Amniotic fluid index and single deepest pocket: weak indicators of abnormal amniotic volumes

OBJECTIVE

To compare amniotic fluid index (AFI) with the single deepest pocket in the identification of actual abnormal amniotic fluid (AF) volumes.

METHODS

One hundred seventy-nine women with singleton pregnancies at the University of Mississippi between March 1994 and June 1999 had ultrasound estimations of AF volume sequentially using the AFI and single deepest pocket techniques. Each woman subsequently had ultrasound-directed amniocentesis with dye-dilution and spectrophotometric calculation of actual AF volume.

RESULTS

Actual AF volumes were low (under 5% by volume for gestational age) in 62 women, normal (5-95%) in 100 women, and high (more than 95%) in 17 women. An AFI up to 5 cm (sensitivity 10%, specificity 96%) and a single deepest pocket up to 2 cm (sensitivity 5%, specificity 98%) were similarly inadequate in identifying dye-determined low AF volumes. Likewise, AFI above 20 (sensitivity 29%, specificity 97%) and a single-deepest pocket above 8 cm (sensitivity 29%, specificity 94%) were poor in identifying dye-determined abnormally high volumes.

CONCLUSION

There was no difference between AFI and single deepest pocket techniques for identifying truly abnormal AF volumes. Both techniques were unreliable for identifying true AF volumes.

Amniotic fluid volume estimation and the biophysical profile: a confusion of criteria

The biophysical profile (BPP) can be used as an initial test of fetal health and as a secondary back-up assessment of fetuses at risk of adverse outcomes when preliminary evaluations are not reassuring. The BPP evaluates five characteristics: fetal movement, tone, breathing, heart reactivity, and amniotic fluid (AF) volume estimation. Three of the most frequently used obstetric textbooks define adequate AF volume differently. In two of the three, the stated method of evaluating AF volume differs from that actually used by the referenced authors. We reviewed articles by Manning and found that his methodology changed from a 1-cm pocket in one plane to a 1-cm pocket in two perpendicular planes, and finally to a 2-cm vertical pocket with a 1-cm horizontal measurement. The 2 x 2-cm pocket is a fourth methodology that has been introduced recently. It is not known how often and in which groups each of the four methods has been used to evaluate abnormal AF volumes. The relevance and importance of determining precisely the ultrasound measurement actually used for investigations are emphasized by looking at women with AF indices < or = 5. Fifty-three percent of those women had a 2 x 2 pocket, 72% had a 2 x 1 pocket, and 95% had a 1 x 1 pocket. The diagnosis of low fluid can lead to additional testing, hydration, and intervention, so the importance of a universal definition linked with pregnancy outcomes cannot be overemphasized.

Leukocytosis is proportional to HELLP syndrome severity: evidence for an inflammatory form of preeclampsia

BACKGROUND

We investigated the possibility that HELLP syndrome is in part a systemic inflammatory response.

METHODS

We evaluated total white blood cell (WBC) counts of all patients with severe preeclampsia with and without HELLP syndrome admitted to our hospital between 1995 and 1997. Patients were grouped by diagnosis and timing of platelet nadir. Analysis of variance and regression analysis were used for data analysis.

RESULTS

Of 177 patients, 91 had HELLP syndrome, and 86 had severe preeclampsia alone. The WBC counts were significantly higher in patients with HELLP syndrome (12.5 +/- .442 x 10(9)/L) than in patients with severe preeclampsia (10.3 +/- .288 x 10(9)/L). Regression analysis showed that platelet counts varied inversely with WBC counts. Also, patients with class I HELLP syndrome had significantly higher WBC counts than patients with other classes of HELLP syndrome.

CONCLUSION

The finding of an association between increasing leukocytosis and worsening thrombocytopenia early in the course of HELLP syndrome supports the hypothesis that it may represent an inflammatory process.

Increasing maternal weight: a risk factor for preeclampsia/eclampsia but apparently not for HELLP syndrome

BACKGROUND

Maternal obesity is a risk factor for severe preeclampsia. We sought to ascertain whether a similar relationship exists between maternal weight and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets) as an atypical form of severe preeclampsia.

METHODS

In this retrospective investigation, 434 patients with HELLP syndrome were assigned to one of four study groups according to maternal weight and were analyzed in relation to selected maternal and perinatal data reflective of disease severity.

RESULTS

We found no significant associations between maternal weight and parameters of HELLP syndrome severity, race, delivery mode, gestational age, or perinatal outcome. Significantly associated with increasing maternal weight were maternal age, parity, admission mean arterial pressure, peak peripartum systolic blood pressures, concurrent essential hypertension, and the interval between admission and delivery. Inversely associated were eclampsia and the interval between delivery and discharge.

CONCLUSIONS

Severity and complications attendant with HELLP syndrome appear unrelated to maternal weight. Paradoxically, eclampsia occurs most commonly in the lighter gravida with HELLP syndrome.

The amniotic fluid index, single deepest pocket, and two-diameter pocket in normal human pregnancy

OBJECTIVE

This study was undertaken to determine normative values for amniotic fluid index, single deepest pocket, and 2-diameter pocket across gestation.

STUDY DESIGN

Fifty patients with normal pregnancies at each gestational age between 14 and 41 weeks' gestation were recruited prospectively and scanned once. Data were transformed into logarithmic (base 10) values for analysis. Polynomial regression equations were used to predict the normal values for amniotic fluid index, single deepest pocket, and 2-diameter pocket across gestational age and to predict the weekly percentage changes.

RESULTS

The mean amniotic fluid index, single deepest pocket, and 2-diameter pocket values were significantly lower among patients at <37 weeks' gestation (n = 1150) than among those at > or =37 weeks' gestation (n = 250; P <.001 for all comparisons). The calculated prevalences of oligohydramnios (amniotic fluid index < or =5 cm, single deepest pocket <2 cm, or 2-diameter pocket <15 cm(2)) were significantly different (P <.0001) for the three techniques (8%, 1%, and 30%, respectively). Hydramnios (amniotic fluid index >24 cm, single deepest pocket >8 cm, or 2-diameter pocket >50 cm(2)) was also diagnosed with significantly different (P <.0001) frequencies (0%, 0.7%, and 3%, respectively).

CONCLUSIONS

This is the largest prospective study to date to provide normative data for each of three ultrasonographic techniques used to assess amniotic fluid volume. The single deepest pocket appears to be the preferable method, because its use is least likely to lead to the false-positive diagnosis of either oligohydramnios or hydramnios.

Determination of amniotic fluid volume in twin pregnancies: ultrasonographic evaluation versus operator estimation

OBJECTIVE

We sought to determine the accuracy of amniotic fluid volume estimation (visually) in diamniotic twin pregnancy versus ultrasonography techniques.

STUDY DESIGN

In this prospective study the volume of each sac in 23 sets of diamniotic twin pregnancies was subjectively and objectively estimated by a second-year obstetric resident, nurse sonographer, maternal-fetal medicine fellow, and maternal-fetal medicine staff. The actual volume was confirmed by amniocentesis and a dye-dilution technique.

RESULTS

There was no difference in the total number of correct estimates of volume by level of operator experience (P =.98), ultrasonography technique (P =.87), or combined subjective versus objective correct estimates (P =.87). Identification of low volume was not different among the four evaluators (P =.48), but the percentage of correct estimates was poor (7%-29%). The 2-diameter pocket was a better predictor of oligohydramnios (57%) than the amniotic fluid index or the largest vertical pocket (12.5%; P =.002).

CONCLUSION

The extremes of volume (low or high) are poorly identified by the subjective or objective assessment of volume.

The effects of physical abuse on pregnancy outcomes in a low-risk obstetric population

OBJECTIVE

This study was undertaken to evaluate the impact of physical abuse on pregnancy outcomes.

STUDY DESIGN

This prospective investigation identified all women seen in the outpatient obstetric clinic with a history of physical abuse and matched each with the next 2 women seen without a history of physical abuse (case/control ratio, 1:2).

RESULTS

Twenty-eight abused women were matched with 56 control subjects. The frequencies of preterm birth, mode of delivery, Apgar scores <7 at 5 minutes, umbilical artery pH <7.10 at birth, and unhappy or ambivalent feelings about the pregnancy were not statistically different between the 2 groups. Admission to the neonatal intensive care unit was more common among infants of the abused women (n = 4 [14.2%] vs n = 2 [3.6%]), despite heavier birth weights in the abused group (3501 +/- 581 g vs 3200 +/- 549 g; P =. 023), but this trend did not reach significance.

CONCLUSION

A history of physical abuse did not result in adverse pregnancy outcomes, although neonatal intensive care unit admission was more likely.

Cesarean delivery for suspected fetal distress among preterm parturients

OBJECTIVE

Among preterm parturients (< 37 weeks) who underwent cesarean delivery for suspected fetal distress, to determine the factors associated with decision-incision time (DIT) of < or = 30 minutes and to assess if umbilical arterial pH < 7.10 is more common with DIT < or = 30 or > 30 minutes.

STUDY DESIGN

The peripartum course of all patients who had cesareans for suspected fetal distress over three years was reviewed. The inclusion criteria were reliable gestational age < 37 weeks and a single indication for cesarean delivery, suspected fetal distress. Twenty antepartum and intrapartum factors were used in a univariate analysis.

RESULTS

The mean DIT among the 84 parturients was 30.5 +/- 21.2 minutes, and 63% of patients had surgery started within 30 minutes. The incidence of pH < 7.10 was 20%. Multivariate analysis indicated that the two factors significantly associated with prolonged time to surgery were tachycardia with decreased variability (odds ratio [OR] 5.9, 95% confidence interval [CI] 1.6-21.6) and use of spinal anesthesia (OR 6.2, 95% CI 1.1-35.0). Though none of the 20 variables had significant univariate associations with neonatal acidosis at alpha = .05, those with P < .20 were considered in multiple logistic regression analysis. None of the 20 factors were associated with pH < 7.10, including DIT of > or = 30 minutes (OR 0.26, 95% CI 0.06-1.03).

CONCLUSION

DIT is likely to be > 30 minutes if cesarean delivery is due to decreased fetal heart variability or if spinal anesthesia is utilized; neonatal acidosis, however, is not significantly associated with a prolonged interval.

Cardiopulmonary morbidity as a complication of severe preeclampsia HELLP syndrome

OBJECTIVE

To profile the types and frequencies of cardiopulmonary morbidity encountered in patients with severe preeclampsia with or without hemolysis, elevated liver enzymes, and low platelets (HELLP syndrome).

STUDY DESIGN

We initiated a retrospective study of 979 patients with severe preeclampsia with and without HELLP syndrome. Types of cardiopulmonary morbidity were analyzed among the three classes of HELLP syndrome and severe preeclampsia without HELLP syndrome.

RESULTS

Cardiopulmonary morbidity occurred in 7.6% of study patients. As a group, patients with cardiopulmonary complications were more likely to have cesareans (11% vs 6%, p = 0.019) earlier in gestation (1366 +/- 700 gm birth weight versus 1734 +/- 892 gm birth weight, p = 0.021), with higher peak postpartum blood pressures (< 0.001) and with more abnormal laboratory values indicative of multisystem disease, compared with patients without this complication. Patients with cardiopulmonary complications required almost twice as long to achieve diuresis as comparison patients (22 +/- 23 hours versus 12 +/- 11 hours, p < 0.001).

CONCLUSION

The probability of cardiopulmonary complications increases significantly when patients develop class 1 HELLP syndrome. Of all cardiopulmonary complications, acute lung injury/acute respiratory distress syndrome is most specific to class 1 HELLP syndrome. Transient renal dysfunction is closely related to cardiopulmonary morbidity.

Sonographic measurements of fetal parts to predict pulmonary maturity among twins and singletons

To determine if sonographic examination of fetus can be readily utilized to predict a mature lecithin/sphingomyelin (L/S) ratio among twins and singletons. Twins (n = 36) undergoing amniocentesis for assessment of pulmonary maturity were matched with singleton (1:2) for maternal demographics, gestational age (GA), and indications for procedure. At the time of amniocentesis, twins and singletons with mature L/S ratios differed significantly in mean GA (33.2 +/- 2.7 vs 34.5 +/- 4.6 wks, p = 0.01), biparietal diameter (BPD), abdominal circumference (AC), femur length (FL) and estimate of birth weight (EFW). Based on ten receiver operating characteristics curves constructed, the following diagnostic thresholds predicted a mature L/S ratio with a true positive rate of 100% among twins and singletons, respectively: 1) BPD $84 and $92 mm; 2) head circumference $315 and $320 mm; 3) AC $295 and $350 mm; or 4) FL $64 and $72 mm; or 5) EFW $2400 and $3200 g. Using any one of these five criteria correctly identified pulmonary maturity among 59% of twins and 28% of singletons (p = 0.001). Sonographic measurement of fetal parts or EFW may be a noninvasive method to predict a mature L/S ration among twins as well as singletons.

Perinatal outcome and amniotic fluid index in the antepartum and intrapartum periods: A meta-analysis

OBJECTIVE

Our purpose was to perform a meta-analysis of studies on the risks of cesarean delivery for fetal distress, 5-minute Apgar score <7, and umbilical arterial pH <7.00 in patients with antepartum or intrapartum amniotic fluid index >5.0 or <5.0 cm.

STUDY DESIGN

Using a MEDLINE search, we reviewed all studies published between 1987 and 1997 that correlated antepartum or intrapartum amniotic fluid index with adverse peripartum outcomes. The inclusion criteria were studies in English that associated at least one of the selected adverse outcomes with an amniotic fluid index of </=5.0 cm versus >5.0 cm. Contingency tables were constructed for each study, and relative risks and standard errors of their logs were calculated. Fixed-effects pooled relative risks were calculated for groups of studies that were homogeneous, whereas random-effects pooled relative risks were calculated for significantly heterogeneous groups of studies.

RESULTS

Eighteen reports describing 10,551 patients met our inclusion criteria. An antepartum amniotic fluid index of </=5.0 cm, in comparison with >5.0 cm, is associated with an increased risk of cesarean delivery for fetal distress (pooled relative risk, 2.2; 95% confidence interval, 1.5-3.4) and an Apgar score of <7 at 5 minutes (pooled relative risk, 5.2; 95% confidence interval, 2.4-11.3). An intrapartum amniotic fluid index of </=5.0 cm is also associated with an increased risk of cesarean delivery for fetal distress (pooled relative risk, 1.7; 95% confidence interval, 1.1-2.6) and an Apgar score <7 at 5 minutes (pooled relative risk, 1.8; 95% confidence interval, 1.2-2.7). A poor correlation between the amniotic fluid index and neonatal acidosis was noted in the only study that examined this end point. More than 23,000 patients are necessary to demonstrate that the incidence of umbilical arterial pH <7.00 is 1.5 times higher among those with oligohydramnios in labor than among those with adequate amniotic fluid index (alpha = 0.05; beta = 0.2)

CONCLUSIONS

An antepartum or intrapartum amniotic fluid index of </=5.0 cm is associated with a significantly increased risk of cesarean delivery for fetal distress and a low Apgar score at 5 minutes. There are few reports linking amniotic fluid index and neonatal acidosis, the only objective assessment of fetal well-being. A multicenter study with sufficient power should be undertaken to demonstrate that a low amniotic fluid index is associated with an umbilical arterial pH <7.00.

Amniotic fluid volume assessment in singleton and twin pregnancies

The best method of ultrasonic mensuration to identify abnormal AFV reliably in singletons and the individual sacs of diamniotic twins remains elusive. With respect to twins, localization of the dividing membrane seems to be necessary for AFV assessments of each amniotic cavity. The relationship of ultrasonic estimates, actual AFV, and pregnancy outcome remains undetermined. In the authors' opinion, the subjective assessment in twin gestation may be as accurate as semiquantitative ultrasonic estimates of AFV, similar to the situation in singleton pregnancies. The authors propose that further prospective research address the following questions: (1) What is the appropriate threshold for intervention when AFI decreases to lower ranges? (2) What other factors (e.g., cervical examination, fetal heart rate patterns, underlying obstetric conditions, fetal growth pattern) are important when the AFI falls to low values in making clinical decisions?

Accuracy of sonographically estimated fetal weight with and without oligohydramnios. A case-control study

OBJECTIVE

To determine the accuracy of sonographically estimated fetal weight among women with and without oligohydramnios (amniotic fluid index [AFI] < or = 5.0 cm) and to ascertain the ability to detect fetal growth restriction (FGR) (estimated birth weight < 10th percentile for gestational age [GA]) among patients in two groups.

STUDY DESIGN

Assuming that 50% of sonographic predictions are within 10% of the birth weight in the study group, 300 parturients are necessary to show a difference of 15% among controls (alpha = .05, beta = .02). The study group consisted of parturients with a reliable GA of > or = 24, no known anomalies and known AFI of < or = 5.0 cm. The control (1:1) was the next patient with the same GA but AFI between 5.1 and 23.9 cm. The paired t test was used, and the odds ratio (OR) and 95% confidence interval (CI) were calculated. P < .05 was considered significant.

RESULTS

Among the study and control groups (N = 162 each), maternal demographics, mean estimate (P = .078) and actual birth weight (P = .091) were similar. Sonographic estimates within 10% of weight were not significantly different among those with (57%) and without oligohydramnios (59%; OR 0.92; 95% CI 0.59, 1.44). The frequency of FGR was higher among those with inadequate fluid (18%) than controls (9%; OR 2.13; 95% CI 1.10, 4.16). Sensitivity, positive predictive value and likelihood ratio were higher among those with oligohydramnios (76%, 78% and 16) than controls (53%, 42% and 7).

CONCLUSION

The accuracy of sonographic estimates of fetal weight is not influenced by whether the parturient has oligohydramnios. Moreover, the accuracy of identifying FGR is not diminished among those with AFI < or = 5.0 versus > 5.0 cm.

Maternal mortality associated with HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome

OBJECTIVE

The aim of this study was to determine factors contributing to deaths among women with HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome.

STUDY DESIGN

Information from multiple sources was scrutinized to distinguish and profile maternal deaths associated with HELLP syndrome.

RESULTS

Information was available regarding 54 maternal deaths. According to HELLP syndrome classification 60.0% had class 1 disease, 35.6% had class 2 disease, and 4.4% had class 3 disease. Events associated with maternal deaths included cerebral hemorrhage (45%), cardiopulmonary arrest (40%), disseminated intravascular coagulopathy (39%), adult respiratory distress syndrome (28%), renal failure (28%), sepsis (23%), hepatic hemorrhage (20%), and hypoxic ischemic encephalopathy (16%). Delay in diagnosis of HELLP syndrome was implicated in 22 of 43 patients' deaths (51.1%).

CONCLUSIONS

It appears that (1) most maternal deaths occurred among women with class 1 HELLP syndrome, (2) delay in diagnosis was associated with mortal consequences, and (3) hemorrhage in the hepatic or central nervous system or vascular insult to the cardiopulmonary or renal system were associated with increased mortality risk.

Twelve steps to optimal management of HELLP syndrome

The early diagnosis and treatment of HELLP syndrome remains problematic for the obstetric health care provider. The nonspecific signs and symptoms of this disorder early in the disease process make the accurate diagnosis difficult and delays early treatment, which has the best prognosis for both maternal and perinatal outcome. The introduction of high-dose nonmineralocorticosteriods to assist in the treatment of these patients is an exciting new development. Use of the 12-step approach to the diagnosis and management of pregnancies complicated by HELLP syndrome has proven to be a successful tool to help us achieve the best possible maternal and perinatal outcome.

Low amniotic fluid volume is poorly identified in singleton and twin pregnancies using the 2 x 2 cm pocket technique of the biophysical profile

BACKGROUND

This study was done to determine the accuracy of the 2 x 2 cm pocket identifying low amniotic fluid (AF) volume in singleton and twin pregnancies.

METHODS

The AF volume was evaluated by ultrasonography for the presence of a 2 x 2 cm pocket before amniocentesis. The actual AF volume was then determined by a diazo-dye reaction with subsequent spectrophotometric analysis using paraminohippurate.

RESULTS

The AF volume was low in 21 of the 79 singleton pregnancies and normal in 47; hydramnios was present in 11. Among amniotic sacs of the 60 twin pairs, oligohydramnios was found in 33 amniotic sacs. normal AF volume in 80 sacs, and high volume in 7. An AF pocket smaller than 2 x 2 cm was identified in only 3 of the 79 singleton pregnancies and in only 2 of the 120 twin amniotic sacs.

CONCLUSIONS

Judging AF volume on the basis of a 2 x 2 cm pocket misses more than 90% of cases of oligohydramnios in singletons and twins.

May-Hegglin anomaly in a pregnancy complicated by intrauterine growth restriction and ambiguous genitalia

OBJECTIVE

Thrombocytopenia as a hematologic disorder complicates up to 4% of all pregnancies. May-Hegglin anomaly is a rare cause of low platelets in pregnancy.

METHODS

A case of May-Hegglin anomaly complicating pregnancy and intrauterine growth restriction in a fetus with ambiguous genitalia is described.

RESULTS

The antepartum and intrapartum diagnosis and management of a patient diagnosed with May-Hegglin anomaly is discussed. The involvement and consultation of a perinatologist, neonatologist, internist, and anesthesiologist is reviewed, with emphasis on the mode of delivery.

CONCLUSION

The potential maternal and fetal complications associated with May-Hegglin anomaly warrant early pregnancy diagnosis and access to a tertiary care facility.

Evaluation of fetal lung maturity in diamniotic twins

OBJECTIVE

This study was undertaken to evaluate the correspondence in fetal lung development between diamniotic twins.

STUDY DESIGN

Lecithin/sphingomyelin ratios were determined for amniotic fluid specimens collected from each sac in 58 diamniotic twin pregnancies.

RESULTS

Overall, the lecithin/sphingomyelin ratios of twin A and twin B and those of the larger and smaller twins of each pair were closely correlated (r >/= 0.83, P <.001). When stratified by gestational age, however, the percentage disparity in lecithin/sphingomyelin ratios between members of twin pairs was significantly greater at </=32 weeks' gestation (25%) than at >32 weeks' gestation (15%, P =.027). An analysis of the lecithin/sphingomyelin ratios of twins with a large lecithin/sphingomyelin ratio disparity (>/=20%) suggested that this disparity was a result of 1 twin having a lecithin/sphingomyelin ratio that was advanced for gestational age with respect to that of the co-twin. Disparities in lecithin/sphingomyelin ratio were not significantly affected by fetal sex or by discordance in size between the twins.

CONCLUSION

At relatively early stages of diamniotic twin gestation (</=32 weeks' gestation), lecithin/sphingomyelin ratios should be obtained for both amniotic sacs to ensure accurate assessment of fetal lung maturity in both twins.

The spectrum of severe preeclampsia: comparative analysis by HELLP (hemolysis, elevated liver enzyme levels, and low platelet count) syndrome classification

OBJECTIVE

This study was undertaken to explore the spectrum of maternal disease with a triple classification system of HELLP (hemolysis, elevated liver enzyme levels, and low platelet count) syndrome and compare these classes with severe preeclampsia without HELLP syndrome.

STUDY DESIGN

In this retrospective analytic study the pregnancies of 777 patients with class 1, 2, or 3 HELLP syndrome were compared and contrasted with those of 193 women with severe preeclampsia but without HELLP syndrome.

RESULTS

Eclampsia, epigastric pain, nausea and vomiting, significant proteinuria, major maternal morbidity, and stillbirth increased as HELLP syndrome worsened from class 3 to class 1. In contrast, headache and diastolic hypertension were more common among the significantly heavier patients with severe preeclampsia without HELLP syndrome. Approximately half of pregnancies complicated by class 1 HELLP syndrome exhibited significant maternal morbidity, compared with only 11% of those complicated by severe preeclampsia without HELLP syndrome. Although a significant trend was apparent in increasing levels of lactate dehydrogenase, aspartate aminotransferase, and uric acid as HELLP syndrome worsened, there was considerable variation within groups.

CONCLUSION

Laboratory and clinical indices of disease severity in patients with severe preeclampsia or eclampsia generally were highest with class 1 HELLP syndrome and were lowest when HELLP syndrome was absent. Class 3 HELLP syndrome is considered a clinically significant transitional group.

Antenatal testing among 1001 patients at high risk: the role of ultrasonographic estimate of amniotic fluid volume

OBJECTIVE

Our goal was to compare the accuracy of the amniotic fluid index and the 2-diameter pocket technique with respect to accuracy in predicting an adverse pregnancy outcome among patients at high risk undergoing antenatal testing.

STUDY DESIGN

All women with high-risk pregnancies and intact membranes who underwent antenatal testing during an 18-month period were prospectively enrolled. Ultrasonographic estimates of amniotic fluid volume were performed by means of the amniotic fluid index and the 2-diameter pocket technique. Relative risks with 95% confidence intervals and receiver operator characteristic curves were calculated for patients with an ultrasonographic estimate of oligohydramnios (amniotic fluid index of </=5 cm or 2-diameter pocket of </=15 cm2) versus normal fluid level (amniotic fluid index of >5 cm or 2-diameter pocket of >15 cm2). Outcome variables studied were intrapartum and neonatal complications.

RESULTS

Among 1001 patients the mean (+/-SD) amniotic fluid index was 10.5 +/- 5 cm and the mean (+/-SD) 2-diameter pocket was 18.7 +/- 13.6 cm2. Significantly more patients (46%) were considered to have oligohydramnios according to the 2-diameter pocket criteria than according to the amniotic fluid index (21%, P <.0001, relative risk 1.7, 95% confidence interval 1.5-1.8). No significant differences in the incidences of nonreactive nonstress test results, meconium-stained amniotic fluid, cesarean delivery for fetal distress, low Apgar scores, or infants with cord pH of <7.10 were observed between the oligohydramnios and normal amniotic fluid groups (P >.05) when assessed by relative risk with confidence interval and by receiver operator characteristic curves.

CONCLUSIONS

Current ultrasonographic measurements with the amniotic fluid index and the 2-diameter pocket technique are poor diagnostic tests to determine whether a patient is at high risk for an adverse perinatal outcome.