Etiology of third-trimester maternal hyperuricemia in nonpreeclamptic twin gestations

OBJECTIVE: To determine whether the higher maternal serum uric acid levels observed in the third trimester of nonpreeclamptic twin gestations result from increased uric acid production or decreased renal excretion. METHODS: Thirty-four nonpreeclamptic subjects with twin gestations were analyzed, along with 34 singleton controls matched for age, ethnicity, prepregnancy weight, height, and gestational age. For each subject, a serum sample and 24-hour urine specimen were obtained in the third trimester. Serum and urine uric acid and creatinine levels were determined, as well as total 24-hour urine uric acid, uric acid clearance, creatinine clearance, fractional uric acid clearance, and net tubular uric acid absorption. RESULTS: The twin gestation group had significantly higher maternal serum uric acid levels (5.2 +/- 1.2 compared with 4.0 +/- 1.0 mg/dL, P <.001) and maternal serum creatinine levels (0.7 +/- 0.2 compared with 0.5 +/- 0.1 mg/dL, P <.001) than the paired singleton group. This was associated with greater 24-hour urine uric acid excretion (688.7 +/- 167.0 compared with 597.7 +/- 164.2 mg, P =.04) and 24-hour urine creatinine excretion (1268.4 +/- 249.9 compared with 1161.2 +/- 277.1 mg, P =.03) in the twin group. No differences were seen between the groups in uric acid clearance, creatinine clearance, fractional uric acid clearance, filtered uric acid load, or net uric acid absorption. CONCLUSION: The higher maternal serum uric acid levels observed in the third trimester of nonpreeclamptic twin gestations result in part from increased uric acid production, as reflected in the increased daily uric acid excretion.     

Relation between serum uric acid and plasma adenosine levels in women with preeclampsia

The aim of this study was to examine the relationship between plasma adenosine and serum uric acid levels in women with preeclampsia. Maternal arterial blood sampling was performed to measure serum uric acid and plasma adenosine levels in 20 pregnant women complicated by preeclampsia and 22 normal pregnant women at 33-38 weeks of gestation. The average plasma adenosine levels were 0.31 +/- 0.12 micromol/l in the normal pregnant group and 0.45 +/- 0.11 micromol/l in the preeclampsia group. The mean serum uric acid level in women with preeclampsia was 5.9 +/- 0.60 mg/dl, significantly higher than in the normal pregnant women (4.4 +/- 0.69 mg/dl). Positive correlations were found between serum uric acid and plasma adenosine levels in both the group with (r(2) = 0.38, p < 0.05) and the group without (r(2) = 0.54, p < 0.05) preeclampsia. There was also a significant correlation between serum uric acid and plasma adenosine levels on the whole (r(2) = 0.59, p < 0.05). Our results suggest that increased adenosine is a contributing source of preeclamptic hyperuricemia.     

Maternal plasma homocysteine concentrations are not increased in twin pregnancies.

OBJECTIVE(S): We tested the hypothesis that twin pregnancies would lead to increased maternal plasma homocysteine. We further hypothesized that twin pregnancies complicated by preeclampsia would have increased plasma homocysteine compared to twin pregnancies without preeclampsia and normal singleton pregnancies. METHODS: Plasma was collected at delivery from 127 nulliparous subjects: 57 women with normal singleton pregnancies, 39 women with singleton and preeclampsia, 17 women with uncomplicated twin pregnancies, and 14 women with twins and preeclampsia. Subjects were group matched for prepregnancy body mass index (BMI) and race. Plasma homocysteine was analyzed by high pressure liquid chromatography (HPLC) with fluorescence detection, and plasma folic acid was measured by radio immunoassay (RIA). RESULTS: The mean plasma concentration of homocysteine was significantly increased in all women with preeclampsia (7.4+/-2.9 microM) compared to all normal pregnant women (5.9+/-2.1 microM, p=0.002). However, homocysteine was not significantly increased in all women with twins (6.7+/-2.1 microM) compared to all women with singleton pregnancies (6.5+/-2.7 microM, p=0.61). In addition, women with twins and preeclampsia did not have increased homocysteine (6.8+/-2.1 microM) compared to women with twins and normal pregnancy (6.7+/-2.1 microM, p=0.72). As expected, because of extra supplementation, plasma folic acid was significantly increased in women with twins (27.9+/-11.6 ng/mL) compared to women with singleton pregnancies (20.8+/-8.5 ng/mL, p=0.0003). However, folic acid was not different between preeclamptics and controls (23.5+/-10.8 vs. 21.9+/-9.2 ng/mL respectively, p=0.36). Lastly, there was a significant inverse correlation between homocysteine and folic acid among all the subjects (r2=- 0.053, p< 0.01), and this correlation persisted in the women with singleton pregnancies (r2=- 0.078, p< 0.01), but was lost in the twins (r2=- 0.073, p=0.14). CONCLUSIONS: With contemporary management including increased folic acid supplementation, plasma homocysteine is not increased in twin pregnancies with or without preeclampsia.     

Maternal plasma adenosine and endothelin-1 levels in twin gestation complicated by preeclampsia

The aim of this study was to evaluate the relationship between the vascular resistance in uterine arteries and the maternal release of adenosine and endothelin-1 in twin gestations with and without preeclampsia. Uterine artery Doppler velocimetry and maternal arterial blood sampling were performed in 14 women with normal singleton gestation, nine women with singleton gestation with preeclampsia, eight women with dichorionic twin gestation without preeclampsia and six women with dichorionic twin gestation with preeclampsia at 28–34 weeks’ gestation. In normal singleton gestations, the average maternal uterine arteries pulsatility index (PI), plasma adenosine and endothelin-1 levels were 0.64±0.07, 0.34±0.11 μmol/l and 1.29±0.31 pg/ml, respectively. In preeclamptic singleton gestations, increased vascular resistance in the uterine arteries (PI: 0.85±0.14, P<0.05) and the elevation of maternal arterial plasma adenosine (0.48±0.14 μmol/l, P<0.05) and endothelin-1 levels (1.91±0.55 pg/ml, P<0.05) were observed. In the normal twin gestation group, the average maternal vascular resistance of the uterine arteries (PI: 0.55±0.09) was lower than that in the normal singleton gestation group, while the average plasma adenosine levels (0.47±0.12 μmol/l) were higher than that in normal singleton gestation. On the other hand, significant increased plasma endothelin-1 concentrations (1.87±0.42 pg/ml) were observed in the preeclamptic twin gestation groups without changes in plasma adenosine levels or vascular resistance of uterine arteries. Our results indicate the presence of different mechanisms for the pathogenesis of preeclampsia between twin and singleton gestations. Received: 5 October 2001 / Accepted: 3 December 2001 Correspondence to S. Suzuki     

Coagulation-fibrinolysis is more enhanced in twin than in singleton pregnancies

AIMS: To examine whether coagulation-fibrinolysis in late pregnancy in women with twin pregnancies is more pronounced than in women with singleton pregnancies. PATIENTS AND METHODS: The plasma levels of D-dimer, fibrinogen/fibrin degradation products (FDP), and fibrinogen, the platelet count, and the antithrombin activity were assessed from 3 weeks before delivery until postpartum day 7 in 48 women (24 singleton and 24 twin pregnancies) without preeclampsia who underwent cesarean sections. RESULTS: Women with singleton or twin pregnancies gave birth at 37.3+/-1.2 weeks or 35.2+/-1.4 weeks, respectively. Compared with singleton mothers, prenatal D-dimer and FDP levels were consistently and significantly higher among women with twin pregnancies. A significantly larger proportion of twin mothers exhibited prenatal levels of D-dimer >5.0 microg/mL, FDP >10.0 microg/mL, fibrinogen <420 mg/mL and antithrombin activity <70%. In addition, prenatal antithrombin activity in plasma was significantly lower. CONCLUSIONS: Coagulation-fibrinolysis is more enhanced in women with twin gestation than in women with singleton gestation.     

Maternal basal metabolic rate in twin pregnancy

OBJECTIVE: This study examined the basal metabolic rate in patients with twin pregnancies and compared the results with those of singleton pregnancies and non-pregnant women. METHODS: In 15 non-pregnant women, 14 patients with twin and 25 patients with singleton pregnancies, the resting energy expenditure was measured using an open-circuit ventilatory system during the third trimester of pregnancy. RESULTS: The averaged resting energy expenditure in patients with twin pregnancy was 1,636 +/- 174 kcal/day, significantly higher than that in patients with singleton pregnancy (1,456 +/- 158 kcal/day; p < 0.05). Both of these levels are significantly higher than those in non-pregnant women (1,228 +/- 132 kcal/day; p < 0.05). CONCLUSION: Our results indicate that the estimated increased metabolic demands in patients during the third trimester of twin pregnancy are about 10% higher than those in women with singleton pregnancy. A prospective clinical study concerning nutrition counseling is needed.     

Increased plasma adenosine concentrations and the severity of preeclampsia

OBJECTIVE: To investigate the relationship between changes in plasma adenosine and the severity of preeclampsia, and norepinephrine and tumor necrosis factor-alpha concentrations. METHODS: Plasma concentrations of adenosine, norepinephrine, and tumor necrosis factor-alpha relating to the pathogenesis of preeclampsia were measured in women with mild (n = 21) and severe (n = 21) preeclampsia and normal pregnancies (n = 21), matched for age, gestational age, and parity, in the third trimester of pregnancy. We then evaluated the relationships among plasma adenosine, norepinephrine, tumor necrosis factor-alpha concentrations, and the severity of preeclampsia. RESULTS: Mean plasma adenosine, norepinephrine, and tumor necrosis factor-alpha concentrations were significantly higher in women with mild and severe preeclampsia than in normal control subjects (P <.05). In women with preeclampsia, plasma adenosine concentrations increased according to the severity of preeclampsia (0.60 +/- 0.03 micromol/L and 0.72 +/- 0.03 micromol/L, respectively, versus 0.41 +/- 0.03 micromol/L for normal subjects), which correlated with increases of norepinephrine and tumor necrosis factor-alpha concentrations (r =.58, P <.05; r =.49, P <.05, respectively). In preeclampsia, norepinephrine concentration also correlated with maternal blood pressure (r =.50, P <.05). CONCLUSION: Adenosine is an established suppressor of the effects of norepinephrine and tumor necrosis factor-alpha. The increased plasma concentrations of adenosine in preeclampsia might serve to counteract further progression of the complication.     

Antithrombin III activity and platelet count are more likely to decrease in twin pregnancies than in singleton pregnancies

BACKGROUND: It is not known whether antithrombin III activity and platelet count are more likely to decrease in women with twin pregnancies than singleton pregnancies. METHODS: We enrolled 56 consecutive women with twin pregnancies and 692 consecutive women with singleton pregnancies. Antithrombin III activity and platelet count were determined at 26-31 weeks and again at 32-40 weeks of gestation. Thrombin-antithrombin complex, and plasmin-alpha2 plasmin inhibitor complex were measured simultaneously in some women. RESULTS: In twin pregnancies, both antithrombin III activity (111 +/- 8.2%) and platelet count (244 +/- 60 x 109/l) at 28.6 +/- 1.0 weeks decreased over time to 91 +/- 12% and 205 +/- 59 x 109/l, respectively, at 35.2 +/- 1.2 weeks; these decreases were significantly greater than in singleton pregnancies. However, a small number of women with singleton pregnancies had a significant decrease in antithrombin III activity in the absence of preeclampsia. The serum thrombin-antithrombin complex was significantly higher in twin pregnancies than in singleton pregnancies (9.7 +/- 4.2 ng/ml vs. 6.7 +/- 4.4 ng/ml, respectively, p < 0.01), and this increase correlated significantly with the decrease in antithrombin III activity in twin pregnancies (r = -0.459, p < 0.001). CONCLUSIONS: Antithrombin III activity and platelet count show a greater decrease in twin than in singleton pregnancies, perhaps due to a greater increase in thrombin generation.     

A study of alpha-human atrial natriuretic peptide in normal pregnancy and in pre-eclampsia.

The object of this study was to compare plasma levels of alpha-human atrial natriuretic peptide (ANP) in patients with pre-eclampsia, normal pregnant women, and healthy non-pregnant women. This was an observational study carried out at Llandough Hospital, Cardiff, Wales on 85 age-matched women divided into three groups (30 patients with pre-eclampsia, 30 healthy pregnant women in the third trimester and 25 healthy non-pregnant women). Plasma ANP concentration was measured between 14.00 and 16.00 hours, in the recumbent position using pre-extraction radioimmunoassay. The following measurements were also performed: blood urea, serum creatinine, serum uric acid and serum sodium in all study subjects and 24-hour urinary protein in pregnant women. All women were eating a normal diet. It was shown that plasma ANP levels were significantly higher in healthy pregnant women in the third trimester of pregnancy than in non-pregnant women (18.12 +/- 7.36 vs. 13.68 +/- 6.41 pmol/l, P < 0.05). This difference was also observed in pre-eclamptic women (17.6 +/- 12.06 pmol/l vs. 13.68 +/- 6.41 pmol/l, P < 0.05) but the plasma hormone levels were not significantly different from healthy pregnant women. In all pregnant women, plasma ANP level was related to the gestational age and birth weight as shown by the regression coefficient (+ 0.39,-0.26 respectively, P < 0.05). In pre-eclamptic patients, there was no relationship between the severity of hypertension, assessed by the level of systolic and diastolic blood pressure, serum uric acid level and amount of proteinuria, and log (plasma) ANP levels. There was a significant negative correlation between serum sodium level and log (plasma) ANP level in all pregnant subjects (r=- 0.51, P < 0.05). Compared with non-pregnant women, plasma ANP levels are increased during the third trimester of normal pregnancy and in pregnancies complicated by pre-eclampsia. A relationship between ANP and pre-eclampsia seems unlikely but ANP is probably involved in the regulation of sodium and water balance in normal pregnancy and in pre-eclampsia.     

Plasma adenosine levels increase in women with normal pregnancies

OBJECTIVE: The aim of this study was to investigate plasma adenosine levels during normal pregnancy and to evaluate the possible roles of platelet activation and 5'-nucleotidase as causes of changes in adenosine levels.Study Design: We measured plasma adenosine levels, the platelet activation markers beta-thromboglobulin and platelet factor 4, and 5'-nucleotidase activity, which catalyzes dephosphorylation from adenosine monophosphate to adenosine, in 34 nonpregnant women and 34 women with normal pregnancies in the third trimester. RESULTS: The mean plasma adenosine level in pregnant women was 0.59 +/- 0.08 micromol/L (mean +/- SEM), which was significantly higher than that found in nonpregnant women (0.18 +/- 0.04 micromol/L; P <.01). In pregnant women plasma beta-thromboglobulin levels, platelet factor 4 levels, and 5'-nucleotidase activity were significantly higher than in nonpregnant women (P <.05). CONCLUSION: The increase of plasma adenosine may be attributed at least in part to platelet activation and an increase of 5'-nucleotidase activity during normal pregnancy. This increase may be an endogenous compensatory mechanism that diminishes platelet activation and maintains vessel integrity during normal pregnancy.     

Twin pregnancy and preeclampsia

INTRODUCTION: Preeclampsia is a pregnancy-specific disorder of humans which rates among one of the major cases of maternal and fetal morbidity and mortality. Etiology of preeclampsia is still largely unraveled and treatment is syndrome specific. OBJECTIVE: Evaluation of the incidence of preeclampsia in twin pregnancies and comparison of selected clinical characteristics among preeclamptic and non-preeclamptic twin pregnancy patients. METHODS: Retrospective analysis of 194 normotensive and 25 preeclamptic patients with twin pregnancies admitted to the Lublin State Hospital Nr 4 between January 1st 1992 and December 31st 1997. Patients were matched for gravidity, parity, maternal age and selected biochemical parameters. RESULTS: Preeclampsia occurred two times more frequently in nulliparous women (68% vs 32%). Gravidas with preeclampsia had significantly higher serum uric acid levels than their non-preeclamptic counterparts (6.7 +/- 0.3 vs 4.3 +/- 0.1; p < 0.001). Hypertension, proteinuria and edema coexisted concomitantly in 52% of preeclamptic patients. CONCLUSIONS: 1. Preeclampsia complicates one tenth of twin pregnancies. 2. In preeclamptic women nulliparas were two times more frequent. 3. In preeclamptic women is significantly higher level of uric acid.     

Twin vs. singleton pregnancy. Clinical characteristics and latency periods in preterm premature rupture of membranes.

OBJECTIVE: To compare the clinical characteristics and latency periods (latencies) of preterm premature rupture of the membranes (PPROM) in twin vs. singleton pregnancy. STUDY DESIGN: Between January 1986 and December 1996, data on all women with singleton and twin gestations complicated by PPROM were reviewed. Perinatal morbidity, mortality and latencies between singleton and twin pregnancies were compared. A further division according to PPROM at < 30 and > or = 30 weeks' gestation was made in both groups. Their latencies were compared. RESULTS: A total of 131 singleton and 48 twin pregnancies with PPROM between 20 and 36 weeks' gestation were included in this series. Regardless of the gestational age at PPROM, the mean latencies of singleton and twin pregnancies were statistically similar (4.4 +/- 3.3 vs. 3.4 +/- 2.9 days, nonsignificant). When PPROM occurred at > or = 30 weeks, the latency of twin pregnancies was shorter than that of singleton pregnancies (2.5 +/- 1.9 vs. 3.7 +/- 2.6 days, P < .05). In both groups, the latencies of PPROM at < 30 weeks were longer than that at > or = 30 weeks (singleton, 5.6 +/- 4.0 vs. 3.7 +/- 2.6 days, P < .005; twin, 4.8 +/- 3.5 vs. 2.5 +/- 1.9 days, P < .05). We also observed a higher percentage of deliveries within the initial 48 hours in twin pregnancies: 50% of women delivered within 48 hours after PPROM and 91.7% within 7 days. In contrast, 26.7% and 85.5% of singleton pregnancies with PPROM were delivered within 48 hours and 7 days, respectively. Perinatal and neonatal outcomes in both groups were similar. CONCLUSION: This investigation provides the basis for patient counseling and management in twin pregnancies with PPROM. In general, singleton and twin pregnancies with PPROM had similar latencies. Latency in PPROM at < 30 was longer than that of PPROM at > or = 30 weeks' gestation in both singleton and twin pregnancies. When PPROM occurred at < 30 weeks' gestation, both groups appeared to have similar latencies. In pregnancies with PPROM at > or = 30 weeks' gestation, latency in twins was shorter than in singleton pregnancies. In twin pregnancies with PPROM after 30 weeks' gestation, prompt steroid administration for fetal lung maturity should be considered.     

Maternal cardiac function in twin pregnancy

OBJECTIVE: To investigate maternal cardiac function in twin pregnancy. METHODS: We conducted a cross-sectional study of 119 pregnant women with twin pregnancies at 10-40 weeks' gestation. Two-dimensional and M-mode echocardiography of the left ventricle was performed in the left lateral decubitus position to assess left ventricular longitudinal and transverse systolic function. The measurements were compared with those obtained from 128 women with singleton pregnancies previously reported. RESULTS: In twin pregnancies, compared with singletons, maternal cardiac output was greater by 20% (P <.001), because of a greater stroke volume (15%, P <.001) and heart rate (3.5%; P =.04). Furthermore, in women with twins there were greater left ventricular end-diastolic and left ventricular end-systolic dimensions, left ventricular mass (13.5%; P <.001), fractional shortening (3%; P =.04), and ejection fraction (2.5%; P =.04). Mean arterial pressure and global time to shortening in women with twins, compared with singletons, were less in the first trimester by approximately 2%, but after midpregnancy they increased progressively, so that at term the measurements were greater by 3% and 5.7%, respectively (P =.03). Conversely, long axis shortening in women with twins, compared with singletons, was greater in the first trimester by approximately 6.5%, but at term it was 3% less (P =.01). Twin pregnancies that subsequently developed preeclampsia had a hemodynamic profile similar to the rest of the twin population. CONCLUSION: Twin pregnancy is characterized by an even more hyperdynamic circulation than singleton pregnancy. Left ventricle longitudinal systolic function and mean arterial pressure are more abruptly affected after 20 weeks compared with singleton pregnancies.     

Clinical outcomes of pregnancy in women with type 1 diabetes(1)

OBJECTIVE:To evaluate predictors of neonatal hypoglycemia and macrosomia in 107 consecutive pregnancies in type 1 diabetic women. METHODS:We conducted a case record analysis of singleton type 1 diabetic pregnancies between January 1994 and January 1999 following institution of standardized management. RESULTS:The duration of diabetes in the women was 12.9 +/- 6.8 years, and 44 were primigravidas. The mean HbA1c throughout pregnancy was 7.2 +/- 0.8%. There was no relationship between neonatal blood glucose (checked before the second feed) and HbA1c at any point in pregnancy or mean pregnancy HbA1c (R = 0.20, P >.1). However, there was a negative correlation between neonatal blood glucose and maternal blood glucose during labor (R = -0.33, P <.001). When maternal blood glucose during labor was greater than 8 mM (144 mg/dL), neonatal blood glucose was usually less than 2.5 mM (mean 1.7 +/- 0.4 mM or 31 mg/dL). There was no relationship between mean HbA1c and birth weight (R = 0.02, P >.1) or between maximum insulin dose and birth weight (R = 0.09, P >.1). Fetal abdominal circumference measured by ultrasound at 34 weeks correlated strongly with birth weight (R = 0.72, P <.001). CONCLUSION:Neonatal hypoglycemia correlates with maternal hyperglycemia in labor, not with HbA1c during pregnancy. Macrosomia does not correlate with HbA1c during pregnancy.     

Effect of fetal number on maternal serum uric acid concentration

The aim of this study was to examine whether maternal serum uric acid (UA) concentrations are influenced by the number of fetuses and whether this effect is confounded by maternal body mass index (BMI). Medical records of 207 consecutive twin and 69 triplet pregnancies admitted to our high-risk pregnancy unit between 1994 and 1998 were reviewed. Pregnancies complicated by acute or chronic renal diseases, vascular diseases, hypertension, hemolysis, diabetes mellitus, or proteinuria were excluded. The remaining 137 twin and 42 triplet pregnancies were matched with 118 consecutive singleton pregnancies who met the same exclusion criteria and were admitted in the first half of 1998. Each birth order study group was further stratified and compared within three maternal BMI subgroups. Serum UA concentrations were higher in twin and triplet pregnancies compared to singletons (4.6 +/- 1.3, 5.2 +/- 1.2, and 3.8 +/- 0.7 mg%, respectively; p <0.01). These differences in UA concentration persisted after grouping by BMI classes. Serum UA concentration in pregnancy are positively correlated with the number of fetuses. For clinical purpose, the UA cutoff concentration should be adjusted using mean + 2 SD as follows: 5.2, 7.2, and 7.6 for singleton, twin, and triplets, respectively.     

Plasma corticotropin-releasing hormone and unconjugated estriol in human pregnancy: gestational patterns and ability to predict preterm delivery.

OBJECTIVE: The purpose of this study was to compare the patterns and timing of the increases in plasma levels of corticotropin-releasing hormone and unconjugated estriol during human pregnancy. STUDY DESIGN: Corticotropin-releasing hormone and unconjugated estriol were measured in serial samples that were collected from preterm subjects and from spontaneous term control subjects who were selected randomly from a study cohort of 297 women. RESULTS: Gestational increases in log corticotropin-releasing hormone and log unconjugated estriol concentrations were best described by linear and cubic polynomial functions, respectively. Plasma unconjugated estriol levels were similar in preterm and term singleton pregnancies at equivalent gestation, whereas corticotropin-releasing hormone was elevated earlier in premature subjects. Mean corticotropin-releasing hormone levels relative to term control subjects (n = 40 women) were shifted forward 16.5 +/- 8.1 days (P =.027, singleton preterm, spontaneous labor; n = 16) and 33.0 +/- 7.9 days (P <.001, singleton preterm, obstetric intervention; n = 10). The corresponding shifts in unconjugated estriol values were -3.8 +/- 2.0 days and -2.7 +/- 5.6 days (both not significant). The prematurity of delivery showed a significant regression on shifts in corticotropin-releasing hormone (P =.004 and P <.001) but not in unconjugated estriol for the 2 groups. The ability to predict prematurity was not significantly improved by regression on corticotropin-releasing hormone and unconjugated estriol shift values together. CONCLUSION: The patterns and timing of gestational changes in corticotropin-releasing hormone and unconjugated estriol differ in humans. The usefulness of corticotropin-releasing hormone as a biochemical preterm marker in singleton pregnancies is not enhanced by the additional measurement of plasma unconjugated estriol.     

Termination of multiple pregnancy at 18-24 weeks' gestation by Laminaria dilatation and evacuation

OBJECTIVE: To compare outcome in women undergoing termination of multiple pregnancy as compared with singleton pregnancy at 18-24 weeks' gestation by Laminaria dilatation and evacuation. STUDY DESIGN: The medical records of 372 consecutive women undergoing does not increase pregnancy termination by Laminaria dilatation and evacuation at 18-24 weeks' gestation between January 1997 and December 2001 were reviewed and divided into a group with multiple pregnancies (38 cases) and a group with singleton pregnancies (334 cases). The 2 groups were then compared for differences in patient characteristics, indications for pregnancy termination and operative outcome. Statistical methods included Student's t and chi2 test. RESULTS: Patients with multiple pregnancies were significantly older (P < .01), and a greater percentage of them were married (P < .001). The percentage of pregnancies following infertility treatment was also significantly higher in the group with multiple pregnancies (P < .0001). Furthermore, significantly more patients with multiple than singleton pregnancy underwent pregnancy termination due to preterm premature rupture of membranes (42.1% vs. 0.3%) (P < .00001), while significantly more singleton pregnancies were terminated due to structural and chromosomal fetal malformations (34.5% vs 10.6%) (P = .03). Operative outcome between the study groups differed mainly regarding blood transfusion; it was significantly greater in the group of patients undergoing multiple, as compared with singleton, termination (7.9% vs. 0.3%) (P < .00001). The group with multiple pregnancy had a longer hospital stay (1.7 +/- 0.9 vs. 1.2 +/- 0.5 days) (P < .001). CONCLUSION: Termination of multiple pregnancies at 18-24 weeks' by dilatation and evacuation appears safe when performed by skilled surgeons. There is an increased need for blood transfusion.     

Maternal serum unconjugated oestriol and human chorionic gonadotrophin levels in twin pregnancies: implications for screening for Down's syndrome.

OBJECTIVE--To investigate maternal serum unconjugated oestriol (uE3) and human chorionic gonadotrophin (hCG) levels in twin pregnancies and to consider the implications of the results for antenatal screening for Down's syndrome. DESIGN--Measurement of maternal serum uE3 and hCG levels from 15-22 weeks of gestation in twin and singleton pregnancies. Previously available maternal serum alpha-fetoprotein (AFP) levels were also presented. SETTING--Stored serum samples collected from women receiving routine antenatal care in Oxford were used. SUBJECTS--200 women with a twin pregnancy and, for each, three singleton control pregnancies matched for gestational age (same completed week of pregnancy) and duration of storage of the serum sample (same calendar quarter). RESULTS--The median uE3, hCG and AFP levels in the twin pregnancies were respectively, 1.67 (95% CI 1.56-1.79), 1.84 (95% CI 1.64-2.07) and 2.13 (95% CI 1.97-2.31) multiples of the median (MoM) for singleton pregnancies at the same gestational age. The variance of values for the three serum markers (expressed in logarithms), and the correlation coefficients between any two, were similar in the twin and singleton pregnancies. CONCLUSION--In maternal serum screening programmes for Down's syndrome dividing uE3, hCG and AFP MoM values in twin pregnancies by the corresponding medians for twin pregnancies will, in expectation, yield a similar false-positive rate in twin pregnancies as in singleton pregnancies.     

Measurement of the total antioxidant response in preeclampsia with a novel automated method

OBJECTIVES: Preeclampsia is one of the most serious complications of pregnancy. Free radical damage has been implicated in the pathophysiology of this condition. In this study, we aimed to measure the antioxidant capacity in plasma samples from normotensive and preeclamptic pregnant women to evaluate their antioxidant status using a more recently developed automated measurement method. STUDY DESIGN: Our study group contained 42 women, 24 of whom had preeclampsia, while 18 had normotensive pregnancies. We measured the total plasma antioxidant capacity for all patients, as well as the levels of four major individual plasma antioxidant components; albumin, uric acid, ascorbic acid and bilirubin, and as a reciprocal measure, their total plasma peroxide levels. RESULTS: Statistically significant differences (determined using Student's t-test) were noted between the normotensive and the preeclamptic groups for their total antioxidant responses and their vitamin C levels (1.31 +/- 0.12 mmol versus 1.06 +/- 0.41 mmol Trolox eq./L; 30.2 +/- 17.83 micromol/L versus 18.1 +/- 11.37 micromol/L, respectively), which were both considerably reduced in the preeclamptic patients. In contrast, the total plasma peroxide levels were significantly elevated in this group (49.8 +/- 14.3 micromol/L versus 38.8 +/- 9.6 micromol/L). CONCLUSIONS: We found a decreased total antioxidant response in preeclamptic patients using a simple, rapid and reliable automated colorimetric assay, which may suitable for use in any routine clinical biochemistry laboratory, and considerably facilitates the assessment of this useful clinical parameter. We suggest that this novel method may be used as a routine test to evaluate and follow up of the levels of oxidative stress in preeclampsia.     

双胎伴胎膜早破36例临床分析

目的探讨双胎伴胎膜早破的临床特点和妊娠结局.方法回顾性分析双胎伴胎膜早破36例(研究组)及同期单胎伴胎膜早破61例(对照组),从胎膜早破的发生率、期待疗法的情况、新生儿预后等情况进行探讨.结果双胎妊娠时胎膜早破的发生率为31.5%,单胎妊娠的胎膜早破发生率为11.7%(P＜0.05);双胎妊娠伴胎膜早破时早产发生率为75.0%,单胎妊娠伴胎膜早破时早产的发生率为11.5%(P＜0.001),双胎妊娠伴胎膜早破时新生儿窒息、羊水粪染、新生儿硬肿症等的发生率均高于单胎妊娠伴胎膜早破(P＜0.001).结论双胎妊娠容易发生胎膜早破、早产、新生儿窒息等,双胎妊娠伴胎膜早破时期待疗法意义不大,双胎妊娠时应尽量避免胎膜早破的发生.