Cerebrovascular disorders complicating pregnancy--beyond eclampsia

OBJECTIVE

Our purpose was to investigate the problems encountered in the diagnosis and management of cerebrovascular disorders associated with pregnancy and the puerperium.

STUDY DESIGN

Pregnancies complicated by cerebrovascular disorders were identified by retrospective chart review (1985 to 1995). Events associated with trauma, neoplasm, drug ingestion, and infection were excluded.

RESULTS

The study population comprised 24 women with a variety of cerebrovascular disorders: 14 with infarction (5 arterial, 9 venous), 6 with intracranial hemorrhage (3 anatomic malformation, 3 unknown etiology), 3 with hypertensive encephalopathy, and 1 with an unruptured aneurysm. Blood pressure reflected physical condition at presentation and did not predict diagnosis or outcome except in the 3 women with hypertensive encephalopathy. Only 4 of 14 women with infarction and 1 of 6 with intracranial hemorrhage had a diastolic blood pressure > or = 110 mm Hg. Presumption of eclampsia delayed the diagnosis in 10 women (41.7%). In addition, patient delay in seeking medical attention complicated 10 cases. After review, none of the adverse maternal outcomes were deemed preventable by earlier physician intervention. Seven maternal deaths occurred (29.2%). Neonatal outcome was related to the gestational age and the maternal condition at presentation.

CONCLUSION

Cerebrovascular disorders are an uncommon and unpredictable complication of pregnancy that are associated with substantial maternal and fetal mortality. Suspected eclampsia unresponsive to magnesium sulfate therapy warrants an immediate neuroimaging study. Interestingly, in women with intracranial hemorrhage, severe hypertension was not an associated predictive factor.

Do twins mature earlier than singletons? Results from a matched cohort study

OBJECTIVE

Our purpose was to determine whether, as a consequence of advanced maturity, preterm twin infants have a more favorable neonatal outcome than matched singleton infants.

STUDY DESIGN

A matched cohort study design was used. Two hundred twenty-four twin infants (112 sets) were matched for gestational age, race, gender, and mode of delivery with singleton infants who were delivered because of refractory preterm labor. Pregnancies with maternal medical disease including preeclampsia, premature rupture of membranes, twin-twin transfusion syndrome, and known fetal anomalies were excluded. Information was obtained by review of maternal and neonatal charts.

RESULTS

There was no difference in the incidence of neonatal death (5% vs 7%, p = 0.66), respiratory distress syndrome (38% vs 35%, p = 0.54), grades 3 and 4 intraventricular hemorrhage (5% vs 4%, p = 0.63), grades 2 and 3 necrotizing enterocolitis (4% vs 6%, p = 0.52), and 5-minute Apgar score < or = 6 (21% vs 21%, p = 1.00). Twins had a higher incidence of admission to the Special Care Unit (88% vs 72%, p < 0.001). Results were similar when analysis was limited to presenting twins, nonpresenting twins, and twins concordant with controls for antenatal glucocorticoid exposure.

CONCLUSION

Twin infants do not have accelerated maturation and improved neonatal outcome compared with matched singleton infants born at the same gestational age because of preterm labor.

The effect of chronic nitric oxide synthesis inhibition on blood pressure and angiotensin II responsiveness in the pregnant rat

OBJECTIVES

Our purpose was to determine whether blockade of inducible or endothelial nitric oxide synthesis prevents maternal vasodilation and blunting of angiotensin II responsiveness in the pregnant rat.

STUDY DESIGN

Pregnant and nonpregnant rats were given (1) drinking water alone (untreated), (2) drinking water containing the inducible nitric oxide synthase inhibitor aminoguanidine (0.5 gm/L), or (3) drinking water containing the nonselective nitric oxide synthase inhibitor N omega-nitro-L-arginine methyl ester (0.5 gm/L) from postmating days 5 to 21. On days 7, 14, and 20, 24-hour urinary nitrate-nitrite excretion, urine protein concentration, hematocrit, mean arterial blood pressure, and pressor responses to angiotensin II (12.5 to 200 ng/kg) were measured. On day 21 litter size, fetal weight, and fetal mortality were determined.

RESULTS

Urinary nitrate-nitrite excretion was increased, and hematocrit and blood pressure were decreased by day 20 of pregnancy. Angiotensin II pressor responses were decreased on days 14 and 20 of pregnancy. Aminoguanidine slightly decreased nitrate-nitrite excretion in pregnant, but not nonpregnant rats, and abolished the late pregnancy increase. Aminoguanidine did not affect hematocrit, blood pressure, or angiotensin II responsiveness in either pregnant or nonpregnant rats. N omega-nitro-L-arginine methyl ester greatly reduced nitrate-nitrite excretion and induced hypertension in both nonpregnant and pregnant rats, but on day 20 blood pressure of the pregnant rats was significantly lower than that of the nonpregnant rats. N omega-nitro-L-arginine methyl ester increased angiotensin II responsiveness on days 14 and 20 only in the pregnant rats. N omega-nitro-L-arginine methyl ester, but not aminoguanidine, increased fetal mortality and decreased fetal weight.

CONCLUSIONS

Inducible nitric oxide synthesis accounts for increased nitrate-nitrite excretion during pregnancy. Endothelium-derived nitric oxide may attenuate angiotensin II responsiveness but does not cause vasodilation and the fall in blood pressure during the last week of gestation.

The effect of magnesium sulfate therapy on the duration of labor in women with mild preeclampsia at term: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

The primary outcome was to determine whether magnesium sulfate therapy prolongs the duration of labor in women with mild preeclampsia. Secondary outcomes were to assess the side effects associated with magnesium sulfate therapy: hours and maximum dose of oxytocin, incidence of progression to severe preeclampsia, incidence of cesarean delivery, change in maternal hematocrit, incidence of postpartum hemorrhage, incidence of maternal infection, and Apgar scores.

STUDY DESIGN

Women with a diagnosis of mild preeclampsia at term were randomized to receive standard therapy during labor and for 12 hours post partum with either magnesium sulfate (n = 67) or a matching placebo solution (n = 68).

RESULTS

There was no difference between magnesium sulfate and placebo with respect to the primary outcome variables: total length of labor (median 17.8 hours vs 16.5 hours, p = 0.7) and length of the active phase of labor (median 5.4 hours vs 6.0 hours, p = 0.5). In addition, no difference was observed in the secondary outcome variables: hours of oxytocin use, change in hematocrit, frequency of maternal infection, progression to severe preeclampsia, incidence of cesarean delivery, and Apgar scores. Although not statistically significant, the incidence of postpartum hemorrhage was approximately fourfold greater in the magnesium sulfate group (relative risk 4.1, 95% confidence interval 0.5 to 35.4). There was a significant difference in the maximum dose of oxytocin used (13.9 +/- 8.6 mU/min with magnesium sulfate vs 11.0 +/- 7.6 mU/min with placebo, p = 0.036).

CONCLUSION

The use of magnesium sulfate during labor in women with mild preeclampsia at term does not affect any component of labor but did necessitate a higher dose of oxytocin.

Fetal plasma levels of cellular fibronectin as a measure of fetal endothelial involvement in preeclampsia

OBJECTIVE

To determine the degree of fetal endothelial involvement in preeclampsia by measuring fetal plasma concentrations of cellular fibronectin.

METHODS

In a prospective cohort study, fetal plasma was collected at delivery from the chorionic plate arteries and veins in a convenience sample of 28 pregnancies complicated by preeclampsia and in 28 normal pregnancies. Stored plasma was assayed for cellular fibronectin using a sensitive and specific enzyme immunoassay. On the basis of a desired power of 0.8, alpha of .05, and expected fetal plasma cellular fibronectin values of 4 +/- 2 micrograms/mL, 26 women were required in each group to detect a 40% difference between the groups. Results were compared using the unpaired Student t test, chi 2 analysis with Yates correction, and linear regression.

RESULTS

There was no statistically significant difference in fetal plasma concentrations of cellular fibronectin in women with preeclampsia compared with normal pregnant women, either in arteries (3.2 +/- 1.1 and 2.9 +/- 1.5 micrograms/mL; P = .33) or veins (3.3 +/- 1.5 and 2.8 +/- 1.6 micrograms/mL; P = .18). Plasma cellular fibronectin concentrations in fetal arteries correlated significantly with those in fetal veins (r = 0.45, P < .001), but not with those in maternal veins (r = 0.15, P = .27).

CONCLUSION

Fetal plasma cellular fibronectin concentrations are similar in preeclamptic and normal pregnancies. We found no evidence that factors responsible for maternal endothelial involvement in preeclampsia are operative in the fetal circulation.

The importance of urinary protein excretion during conservative management of severe preeclampsia

OBJECTIVES

We determined the natural course of urinary protein excretion during conservative management of severe preeclampsia and investigated whether changes in urinary protein excretion can predict maternal or perinatal outcome.

STUDY DESIGN

We reviewed the medical charts of 66 women with severe preeclampsia which was managed conservatively before 32 weeks of gestation and who had at least two 24-hour urinary protein determinations 4 or more days apart after admission.

RESULTS

Fifty-nine (89%) of 66 women had an increase in proteinuria during conservative management of severe preeclampsia. The median increase in protein excretion after admission was 660 mg/24 hours (range-4580 to 18,960 mg/24 hours). Patients were divided into two groups. The first group (n = 24) had an increase in 24-hour urinary protein excretion of > or = 2 gm; the second group (n = 42) had a 24-hour urinary protein excretion that decreased (n = 7) or increased by < 2 gm (n = 35). There were no cases of eclampsia or stillbirth in either group. The rate of HELLP (hemolysis, elevated liver enzyme levels, low platelet counts) syndrome, abruptio placentae, cesarean delivery because of fetal distress, 5-minute Apgar scores < or = 6, and the admission-to-delivery intervals were all similar in the two groups.

CONCLUSIONS

Proteinuria increases in most women with severe preeclampsia managed conservatively. No differences in maternal or fetal outcomes were found between pregnancies with marked increases in proteinuria and those with modest or no increases.

Dietary consumption and plasma concentrations of vitamin E in pregnancies complicated by preeclampsia

OBJECTIVE

Vitamin E, a potent antioxidant, has been suggested to play a role in preventing preeclampsia. Our aim was to determine whether consumption and plasma levels of vitamin E are lower in the preeclamptic than in normal women.

STUDY DESIGN

A case-control study design was used. We identified 48 women with preeclampsia (late-pregnancy hypertension, proteinuria, and hyperuricemia). Ninety normal women served as the control group. Vitamin E consumption was estimated by use of a previously validated dietary recall questionnaire administered by a single trained research nurse to 42 of the preeclamptic women and all 90 of the control women. Blood was drawn from all women and stored until assayed at -70 degrees C. Plasma vitamin E concentrations were determined by use of high-pressure liquid chromatography.

RESULTS

The mean dietary vitamin E consumption was similar for both the preeclamptic and control group (11.74 +/- 9.39 vs 11.34 +/- 7.51 mg/24 hr, p = 0.73). When the analysis also included estimations of vitamin E supplements, the total consumption was found to be higher in those who had preeclampsia than in controls (37.20 +/- 20.54 vs 22.3 +/- 27.24 mg/24 hr, p = 0.003). The mean plasma vitamin E concentration was significantly higher in preeclamptic than in control patients (1.41 +/- 0.39 vs 1.15 +/- 0.32 mg/dl, p < 0.001). Among the preeclamptic patients, those with severe disease associated with HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome (n = 11) had the highest plasma vitamin E concentrations.

CONCLUSIONS

We found no evidence that low vitamin E consumption is related to the development of preeclampsia. Higher plasma vitamin E concentrations in preeclamptic patients are speculated to represent a response to oxidative stress.

Serial amniotic fluid index in severe preeclampsia: a poor predictor of adverse outcome

OBJECTIVE

The purpose of the study was to determine the relationship between low amniotic fluid index and intrauterine growth restriction and nonreassuring fetal testing in patients with severe preeclampsia.

STUDY DESIGN

We reviewed the medical records of 136 women with severe preeclampsia managed conservatively for at least 48 hours. Patients were followed up with a daily nonstress test and amniotic fluid index. We evaluated amniotic fluid index < or = 5 cm and < or = 7 cm, measured on admission or just before delivery (i.e., final), and attempted to correlate these findings with the incidence of nonreassuring fetal testing necessitating cesarean section or the incidence of intrauterine growth restriction (birth weight < or = 10th percentile).

RESULTS

One hundred seven patients had a cesarean section, but only 42 (39%) of these were for a nonreassuring fetal heart rate tracing or a persistent biophysical profile of < or = 4, and 38 (36%) of the pregnancies resulted in infants with intrauterine growth restriction. During expectant management, the amniotic fluid index worsened for 61 (45%) patients and improved or remained the same for 75 (55%). For those with an amniotic fluid index of < or = 5 cm both on admission and at delivery, there was a significantly higher incidence of intrauterine growth restriction compared with those with an amniotic fluid index > 5 cm (p = 0.007 and p = 0.029, respectively). However, there was no association between intrauterine growth restriction and an amniotic fluid index < or = 7 cm. Moreover, there was no difference in the frequency of nonreassuring fetal heart rate testing on the basis of amniotic fluid volume (p = 0.59) or intrauterine growth restriction (p = 0.4).

CONCLUSIONS

For women with severe preeclampsia remote from term, an amniotic fluid index < or = 5 cm is predictive of intrauterine growth restriction but lacks sensitivity. There is no association between the amniotic fluid index status and frequency of cesarean section for fetal distress or nonreassuring fetal testing.

Trial of Calcium for Preeclampsia Prevention (CPEP): rationale, design, and methods

The results of ten clinical trials suggest that supplemental calcium may prevent preeclampsia. However, methodologic problems and differences in study design limit the acceptance of the results and their relevance to other patient populations. Many of the trials were conducted in countries where, unlike the United States, the usual daily diet contained little calcium. Moreover, none of the trials has reported the outcome of systematic surveillance for urolithiasis, a potential complication of calcium supplementation. In response to the need for a thorough evaluation of the effects of calcium supplementation for the prevention of preeclampsia in the United States, the trial of Calcium for Preeclampsia Prevention (CPEP) was undertaken at five university medical centers. Healthy nulliparous patients were randomly assigned to receive either 2 g supplemental calcium daily (n = 2295) or placebo (n = 2294) in a double-blind study. Study tablets were administered beginning from 13 to 21 completed weeks of gestation and continued until the termination of pregnancy. CPEP employed detailed diagnostic criteria, standardized techniques of measurement, and systematic surveillance for the major study endpoints and for urolithiasis. The nutrient intake of each patient was assessed at randomization and at 32-33 weeks gestation. This report describes the study rationale, design, and methods.

Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome in pregnancy: review of 11 cases

OBJECTIVE

Little information exists regarding thrombotic thrombocytopenic purpura and hemolytic uremic syndrome during pregnancy. We report a series of thrombotic thrombocytopenic purpura and hemolytic uremic syndrome complicating pregnancy, with emphasis on diagnosis and management of this rare disorder.

STUDY DESIGN

Between January 1988 and February 1996, 11 women with either thrombotic thrombocytopenic purpura (n = 8) or hemolytic uremic syndrome (n = 3) were evaluated. Clinical and laboratory findings and maternal and neonatal outcomes were recorded from the medical records.

RESULTS

Eight of the 11 women were in the third trimester or peripartum period, and three were seen before fetal viability. Treatment included fresh-frozen plasma in all women, plasmapheresis (n = 8), packed red blood cells (n = 9), and platelet transfusions (n = 5); 1 patient required splenectomy. There were two maternal deaths. Of the 9 surviving women, 4 had chronic renal disease, 1 of whom also had residual neurologic deficit. Preterm delivery occurred in 5 of 8 pregnancies continuing beyond 20 weeks. Indications for delivery in these 5 women included worsening maternal medical disease, nonreassuring fetal testing, and spontaneous preterm labor. Six of 8 women with viable fetuses underwent cesarean delivery. These 6 infants were born in good condition without thrombocytopenia. Of the remaining 2 infants delivered vaginally, one was healthy at 35 weeks and the other was stillborn.

CONCLUSION

Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome complicating pregnancy is associated with high maternal mortality and long-term morbidity. Preterm delivery and intrauterine fetal death are frequent complications of these pregnancies. Improved survival after this disorder has been attributed to aggressive treatment with plasma transfusion or plasmapheresis.

Clinical utility of strict diagnostic criteria for the HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome

OBJECTIVE

Our purpose was to compare the maternal outcome of pregnancies complicated by HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome, partial HELLP syndrome, or severe preeclampsia.

STUDY DESIGN

In a retrospective cohort study we reviewed the maternal charts of 316 women with HELLP syndrome or severe preeclampsia managed at our perinatal center between July 1, 1992, and June 30, 1995. HELLP syndrome was strictly defined by previously published laboratory criteria. Women were divided into three groups: HELLP syndrome (n = 67), partial HELLP syndrome (one or two but not all three features of HELLP syndrome, n = 71), and severe preeclampsia (no features of HELLP syndrome, n = 178). Results were compared by chi 2 analysis and one-way analysis of variance.

RESULTS

Mean gestational ages at delivery in the HELLP, partial HELLP, and severe preeclampsia groups were, respectively, 31.7, 32.7, and 34.5 weeks (p < 0.001 between HELLP and severe preeclampsia). There was one maternal death from intracerebral hemorrhage in the HELLP group. In women with HELLP syndrome there was a higher incidence of cesarean section (p < 0.05), disseminated intravascular coagulation (p < 0.001), and need for transfusion (p < 0.001) than in the other two groups.

CONCLUSIONS

Higher incidences of maternal complications in women with HELLP syndrome stress the importance of strict criteria for the definition of HELLP syndrome. Women with partial HELLP syndrome should be studied and managed separately from women with complete HELLP syndrome.

Maternal and neonatal outcome of 846 term singleton breech deliveries: seven-year experience at a single center

OBJECTIVE

Our purpose was to evaluate the maternal and neonatal outcome of 846 consecutive term singleton breech deliveries at a single center.

STUDY DESIGN

We reviewed the maternal and neonatal charts of all women who delivered singleton breech fetuses between 1984 and 1990 and divided them into two groups: women who fulfilled the criteria for trial of labor (group 1, n = 613) and those who did not meet these criteria and underwent scheduled cesarean section (group 2, n = 233).

RESULTS

In group I, 326 women (53.2%) were delivered vaginally. There were no maternal deaths. Febrile morbidity and length of hospitalization were significantly higher in the women who required cesarean section in labor compared with those delivered vaginally. In the total study population there were no stillbirths and eight neonatal deaths, 6 of which had major malformations incompatible with life. The remaining two deaths occurred in group I (0.33% corrected neonatal mortality in group 1). Newborns in Group 1 exhibited a higher rate of trauma with borderline statistical significance (3.0% vs 0.5%, p = 0.052). No significant differences were found in the rates of low Apgar scores, intubation, and intensive care unit admission.

CONCLUSION

Although certain short-term outcome variables may appear less favorable in term singleton breech infants delivered vaginally, large randomized studies of short- and long-term outcome should be undertaken because current data are not sufficiently conclusive to warrant routine cesarean section for term breech presentation.

Is fetal neurologic and physical development accelerated in preeclampsia?

OBJECTIVE

Our objective was to determine whether the Ballard score, a maturity score for neonatal neuromuscular and physical development, is more advanced in preterm infants of preeclamptic women than in controls.

STUDY DESIGN

A matched cohort study design was used. One hundred women with strictly defined preeclampsia (new-onset hypertension, proteinuria, and hyperuricemia) were matched for gestational age, race, and gender to 100 normotensive women with preterm delivery. All patients had an assigned antenatal gestational age based on ultrasonography before 24 weeks. The gestational age, based on antenatal ultrasonography and last menstrual period, was compared with the Ballard score given at the time of neonatal physical examination within the first 12 hours after delivery. The difference in gestational age between the Ballard score and antenatal ultrasonography (Ballard score - ultrasonography) was calculated for each patient. Results are expressed as median and range and are compared with a Student t test.

RESULTS

The mean gestational age at delivery by antenatal ultrasonography in patients with severe preeclampsia was 32.06 +/- 2.74 and 32.03 +/- 2.70 weeks, respectively. The median difference between scores in patients with severe preeclampsia and normal patient were 1.3 +/- 1.8 and 1.5 +/- 1.6 weeks, respectively (p = 0.41).

CONCLUSION

On the basis of criteria defined by the Ballard score, preeclampsia was not associated with accelerated fetal neurologic and physical development.

Plasma and placental calcitonin gene-related peptide in pregnancies complicated by severe preeclampsia

OBJECTIVE

Our purpose was to determine the concentration of calcitonin gene-related peptide, a potent vasodilator, in maternal plasma, fetal plasma, and placental tissue from pregnancies complicated by severe preeclampsia.

STUDY DESIGN

The following groups were studied: severe preeclampsia (group 1, n = 21), normal pregnancies matched for mode of delivery (group 2, n = 21), and nonpregnant women (group 3, n = 17). Maternal venous blood samples were drawn before labor, and fetal venous samples were drawn from the chorionic plate immediately after delivery. Calcitonin gene-related peptide was also quantified in placental tissue samples from 15 patients in group 1 and 15 patients in group 2. Calcitonin gene-related peptide was measured with a sensitive and specific radioimmunoassay.

RESULTS

No differences were found between maternal plasma calcitonin gene-related peptide concentrations in groups 1 and 2 (29.8 +/- 4.2 and 30.4 +/- 4.3 pmol/L, respectively). Both had levels similar to those in group 3 (28.5 +/- 5.4 pmol/L). Maternal plasma concentrations in the preeclamptic group were unchanged 3 days post partum (29.1 +/- 3.6 pmol/L). Fetal plasma calcitonin gene-related peptide concentrations were similar in groups 1 and 2 (30.2 +/- 3.9 and 32.2 +/- 8.8 pmol/L, respectively). A significant correlation was found between maternal and fetal calcitonin gene-related peptide concentrations (r = 0.43, p < 0.01). Like plasma levels, calcitonin gene-related peptide levels in the supernatants of placental extracts were not different in preeclamptic and normal pregnancies (108.0 +/- 70.4 and 100.9 +/- 56.1 fmol/gm, respectively).

CONCLUSION

On the basis of plasma and placental concentrations, calcitonin gene-related peptide does not seem to play an important role in the pathophysiologic mechanisms of preeclampsia.

Daily antenatal testing in women with severe preeclampsia

OBJECTIVE

Our purpose was to determine whether daily antenatal testing in the expectant management of severe preeclampsia remote from term prevents stillbirth or neonatal compromise at birth.

STUDY DESIGN

We reviewed the medical records of 68 women with severe preeclampsia remote from term who underwent expectant management with daily fetal testing until delivery. On admission each patient had reassuring nonstress testing (absence of persistent severe variable or late decelerations), biophysical profile (> or = 6), and amniotic fluid volume (> or = 2 cm maximal vertical pocket before 32 weeks or amniotic fluid index > or = 5 after 32 weeks).

RESULTS

There were no stillbirths. Twenty-one patients (31%) had nonreassuring testing necessitating delivery. Two neonatal deaths occurred as a result of complications of prematurity. There were no statistical differences in the cord arterial pH (p = 0.93) or in the 1- and 5-minute Apgar scores (p = 0.18 and p = 0.88, respectively) between those with normal and abnormal antenatal testing.

CONCLUSIONS

Because optimizing neonatal outcome is the only reason to prolong pregnancy in women with severe preeclampsia, confirmation of fetal well-being is mandatory. Because neither stillbirths nor fetal compromise at birth occurred in patients undergoing daily antenatal testing, we recommend daily testing in patients with severe preeclampsia managed expectantly.

Preeclampsia and related disorders. Clinical aspects and relevance of endothelin and nitric oxide

Preeclampsia is a pregnancy-specific disorder believed to result from widespread endothelial dysfunction. Endothelin and NO are two potent vasoactive agents of endothelial origin and, as such, are postulated to play an important role in the pathogenesis of preeclampsia. If these agents are found to be important in preeclampsia, they will most likely exert their effects locally, rather than systemically. Future research on the autocrine and paracrine effects of endothelin and NO may yield important insights into the cause and pathogenesis of this enigmatic disease.

Neonatal outcome after preterm delivery for preeclampsia

OBJECTIVE

Our purpose was to determine whether maternal preeclampsia per se has a beneficial effect on neonatal outcome after delivery before 35 weeks.

STUDY DESIGN

A matched cohort study design was used. Two hundred twenty-three infants of strictly defined preeclamptic women were matched for gestational age, race, gender, and mode of delivery with infants of normotensive women with preterm labor and delivery. Pregnancies with multiple gestation, premature rupture of membranes, known fetal anomalies, diabetes, or maternal medical disease were excluded. Information was obtained by review of maternal and neonatal charts. Paired categoric and continuous data were compared by McNemar's test and the Wilcoxon signed-rank test, respectively.

RESULTS

There was no difference in the incidence of neonatal death (4.5% vs 4.5%, p = 0.82), respiratory distress syndrome (22.0% vs 22.0%, p = 0.88), grades 3 and 4 intraventricular hemorrhage (2.2% vs 2.2%, p = 0.72), grades 2 and 3 necrotizing enterocolitis (5.8% vs 4.0%, p = 0.48), and culture-proved sepsis (9.0% vs 9.0%, p = 0.85). Results were similar when analysis was limited to infants born at < or = 32 weeks, infants born to mothers with severe preeclampsia, and infants with intrauterine growth restriction.

CONCLUSION

Maternal preeclampsia per se does not have a beneficial effect on the postnatal course of infants born at 24 to 35 weeks' gestation.

Identification of the domain within fibroblast growth factor-1 responsible for heparin-dependence

While the prototype members of the fibroblast growth factor (FGF) family, FGF-1 and FGF-2 are structurally related, the structural differences between these polypeptides predict that they will ultimately exhibit different biological roles. Indeed, a significant difference between these proteins is the dependence of FGF-1 on heparin for the generation of maximal mitogenic activity. In order to gain structural insight into the issue of FGF-1 heparin-dependence, a synthetic gene encoding FGF-2 was constructed with oligonucleotides in a four-cassette format similar to a synthetic gene previously constructed for FGF-1 (Forough et al. 1992, Biochem. Biophys. Acta 1090 293-298). This strategy permitted the molecular shuffling of corresponding cassette(s) between FGF-1 and FGF-2 to yield FGF-1:FGF-2 chimeras. Three amino acid changes (Lys86-->Glu, Tyr120-->His, and Thr121-->Ala) were introduced into the synthetic FGF-2 gene by the cassette format to generate convenient FGF-1 restriction sites, but these alterations did not significantly affect the mitogenic activity or the heparin-binding affinity of the recombinant FGF-2 protein when compared with native FGF-2. Among the various FGF-1:FGF-2 chimeric constructs, one designated FGF-C(1(1/2)1 1), which represents FGF-1 containing FGF-2 amino acid residues 65 to 81, displayed FGF-1-like heparin-binding affinity but it did not require the addition of exogenous heparin to manifest its mitogenic activity. These data suggest that the sequence within residues 65 and 81 from FGF-2 significantly contributes to the heparin-dependent character of FGF-1.

Plasma from preeclamptic women increases human endothelial cell prostacyclin production without changes in cellular enzyme activity or mass

OBJECTIVE

We investigated differences in prostacyclin production by endothelial cells exposed to plasma from either preeclamptic women or normal pregnant women.

STUDY DESIGN

A case-control study of matched preeclamptic and normal pregnancies was used to compare prostacyclin synthesis by human umbilical vein endothelial cells incubated with pregnancy plasma for 24 hours. Prostacyclin concentrations in conditioned media were measured by radioimmunoassay of its stable metabolite (6-keto-prostaglandin F1 alpha). Human umbilical vein endothelial cell lysates were used to determine concentrations of the enzymes cyclooxygenase and prostacyclin synthase.

RESULTS

Prostacyclin production by human umbilical vein endothelial cells incubated with plasma from preeclamptic women was significantly greater than that by cells exposed to normal pregnancy plasma. Differences in prostacyclin production under the two experimental conditions could be explained neither by differences in enzyme mass nor activities of cyclooxygenase and prostacyclin synthase.

CONCLUSION

The stimulatory effect of preeclampsia plasma on prostacyclin biosynthesis in human umbilical vein endothelial cells appears to be manifested at a step(s) proximal to the activation of cyclooxygenase. Possible mechanisms are increased phospholipase A2, lipoprotein, or lipid peroxide activities in preeclampsia.

Pregnancies complicated by HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets): subsequent pregnancy outcome and long-term prognosis

OBJECTIVE

Our purpose was to describe subsequent pregnancy outcome and long-term maternal prognosis in women with HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets) during the index pregnancy.

STUDY DESIGN

This is a descriptive and analytic study of women with HELLP syndrome admitted to E.H. Crump Women's Hospital between August 1977 and July 1992. HELLP syndrome was defined by previously published laboratory criteria. Only patients who were delivered > 2 years ago were included (median 4 years, range 2 to 14 years). Data on these patients were obtained from our obstetric clinics, local physicians, local health departments, and hospital records.

RESULTS

Adequate follow-up data were available on 341 patients. One hundred fifty-two women subsequently became pregnant. One hundred thirty-nine normotensive women had 192 subsequent pregnancies. Complications included preeclampsia (19%), preterm delivery (21%), intrauterine growth restriction (12%), abruptio placentae (2%), perinatal death (4%), and HELLP syndrome (3%). Seven of the 113 women with at least 5 years' follow-up (6.2%) had chronic hypertension, and 98 received oral contraceptive pills without complications. Thirteen women with preexisting chronic hypertension had 20 subsequent pregnancies. These women had a higher rate of preeclampsia (75%), preterm delivery (80%), intrauterine growth restriction (45%), abruptio placentae (20%), and perinatal death (40%) but a low rate of recurrent HELLP syndrome (5%).

CONCLUSIONS

Women with HELLP syndrome have an increased risk of obstetric complications in future pregnancies but a low risk for recurrent HELLP syndrome. Oral contraceptive pills should not be contraindicated in normotensive women.

Biochemical corroboration of endothelial involvement in severe preeclampsia

This prospective, nested, case-control study investigated whether elevated plasma cellular fibronectin concentrations previously reported in preeclamptic women likely reflect endothelial dysfunction. In addition to higher maternal plasma concentrations of cellular fibronectin, we found higher levels of von Willebrand factor, tissue plasminogen activator, and plasminogen activator inhibitor-1 in maternal plasma, providing biochemical corroboration of endothelial dysfunction in severe preeclampsia.

Conservative management of severe preeclampsia remote from term

Traditionally, preeclamptic women who meet established criteria for severe disease are delivered expeditiously. Although delivery is always appropriate therapy for the mother, it may not be for the fetus remote from term. Two recent randomized clinical trials have demonstrated favorable neonatal outcomes after conservative management of severe preeclampsia remote from term. Nevertheless, because such management entails risk for both the mother and fetus, patients must be selected carefully. We consider women who have severe disease--by ACOG criteria for blood pressure (systolic persistently at least 160 mmHg or diastolic persistently at least 110 mmHg) or proteinuria (5 g/day or greater)--to be candidates for conservative management with close maternal and fetal surveillance. As long as maternal blood pressure can be controlled pharmacologically, maternal laboratory values are stable, and fetal biophysical profiles are normal, we manage these patients conservatively up to 34 weeks' gestation. Using these guidelines at our institution, we found that approximately two-thirds of patients with severe preeclampsia before 34 weeks were eligible for conservative management. We recommend that such management be performed only at tertiary perinatal centers.

Obstetric characteristics among nulliparas under age 15

OBJECTIVE

To describe and analyze the obstetric characteristics of adolescent women under 15 years of age.

METHODS

A matched cohort design was used. The pregnancies of 261 nulliparous women under age 15 delivered at our institution between January 1990 and December 1992 were compared to 261 nulliparous controls aged 20-29, matched for race, infant gender, and year of delivery. Multiple gestation and delivery immediately after hospital admission were exclusion criteria.

RESULTS

The number of antepartum admissions was identical (n = 35 in each group). There were no significant differences between the study and control groups in cervical dilatation at admission, frequency of labor induction (12.6% for each), epidural anesthesia (44.4 versus 49.4%), mean birth weight (2918 +/- 661 versus 2979 +/- 753 g), or preterm birth (24.1 versus 20.3%). Use of oxytocin was less common and magnesium sulfate more common in the adolescent group. Nevertheless, the duration of the active phase of labor and the rate of cesarean delivery were significantly lower in the adolescent group (4.5 +/- 2.7 versus 5.2 +/- 2.4 hours, P = .02; and 13.8 versus 25.3%, P = .001, respectively). The incidence of operative vaginal delivery was not different between the groups. Analysis of the data after controlling for fetal presentation, marital status, and insurance status did not alter these findings. Postpartum complications were similar.

CONCLUSION

Pregnancy at the lower limit of reproductive age in an urban American population is not associated with an abnormal labor course, as is commonly believed.