British journal of obstetrics and gynaecology最新文献

Objective 1.To evaluate the activation profile of the endothelium in pregnancies complicated by small for gestational age fetuses compared with pre-eclampsia and normal pregnancy, by measuring the plasma levels of soluble adhesion molecules soluble E-selectin, intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1. 2. To determine whether soluble adhesion molecules were related to the severity of small for gestational age fetuses and pre-eclampsia.

Design Observational study.

Participants Sixteen women with small for gestational age fetuses; 15 women with pre-eclampsia and 15 healthy primigravidae were recruited as controls.

Methods Plasma levels of soluble E-selectin, intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1 were measured by ELISA.

Results Compared with the healthy controls, soluble E-selectin was significantly increased in both small for gestational age fetuses and pre-eclampsia, whereas intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1 were increased only in pre-eclampsia. In the small for gestational age fetuses group, soluble E-selectin correlated inversely with the ratio between birthweight and the expected normal birthweight (r=-0.4, P=0.007). In the pre-eclampsia group, a significant correlation was observed between vascular cell adhesion molecule-1 and blood pressure (r=0.54, P=0.039).

Conclusions Endothelial activation, reflected by raised levels of soluble E-selectin, is a feature of small for gestational age fetuses and is correlated with the severity of the disease. Differences in the profile of soluble cell adhesion molecules suggest variations in the degrees of endothelial activation between pre-eclampsia and small for gestational age fetuses.

Objective To compare maternal serum leptin concentration in women with pre-eclampsia and women with normal pregnancy, and to evaluate the relationships between leptin and several inflammatory cytokines.

Design Prospective clinical study.

Setting University Hospital of Puerto Real, Cadiz, Spain.

Sample Twenty-seven women with pre-eclampsia and 25 normotensive pregnant women.

Methods Maternal serum levels of TNF-α, TGF-β1, interleukin 6, and leptin were measured using a commercially available immunoassay.

Main outcome measures Maternal serum levels of leptin and its relationship to levels of TNF-α, TGF-β1 and interleukin 6.

Results Maternal serum leptin levels were higher in women with pre-eclampsia, but this difference was of borderline statistical significance (median 15.9ng/mL; interquartile range (5.4–31.9) vs 30.5ng/mL (13.9–64) (P=0.05). The concentration of maternal serum leptin was correlated with pre-gestational and gestational body mass index (r=0.45, P=0.03; r=0.44, P=0.04), TNF-α concentration (r=0.57, P=0.002) and interleukin-6 level (r=0.46, P=0.02) in women with normal pregnancy. In women with pre-eclampsia, only a significant correlation between maternal serum leptin level and TNF-α concentration (0.47, P=0.01) was found.

Conclusions The level of maternal serum leptin is increased and correlates positively with the level of TNF-α in women with pre-eclampsia. In women with a normal pregnancy leptin levels not only correlate with TNF-α, but also with IL-6 and body mass index.

Objective To evaluate the relative contribution of cord occlusion length intervals between occlusions and experimental duration on oxidative stress in the fetal lamb brain.

Design Acute, partially exteriorised fetal lambs with intermittent total cord occlusion.

Setting The Vivarium of Westmead Hospital, University of Sydney, Australia and The Chinese University of Hong Kong.

Main outcome measures Arterio-venous differences in the concentration of organic hydroperoxides, measured in paired samples of carotid arterial and jugular venous blood, as an index of oxidative stress in the brain.

Methods Thirty-two fetal lambs were exposed to graded hypoxia, induced by intermittent total umbilical cord compression of 30 seconds, 60 seconds and 90 seconds duration, occurring every minute for a total of 27 occlusions over 81 minutes. Three sham experiments were also performed. In addition to organic hydroperoxides, carotid arterial blood samples were also assayed in 15 animals (two sham) for oxygen saturation, pH, hypoxanthine, xanthine and urate concentrations. A causal model for oxidative stress was defined: occlusions leading to hypoxia with a rise in hypoxanthine; reperfusion during intervals between occlusions leading to the accelerated production of xanthine and uric acid and the generation of oxygen free radicals, which in turn, are responsible for the rise in lipid peroxidation. Path analysis was performed to assess the strength of the relationships between these variables and the cord occlusion length, the interval between occlusions and the duration of the experiment.

Results Sham experiments showed no change in organic hydroperoxide production. Following 30-second umbilical cord occlusions a sixfold drop in mean organic hydroperoxides was observed between carotid arterial and jugular venous levels. In contrast, following occlusions of 60 seconds duration (or longer) a median 20-fold increase in organic hydroperoxide production was observed. Path analysis revealed a strong indirect pathway from occlusion length → hypoxanthine → urate and weak positive pathways from oxygen saturation→ urate and from interval between occlusions → urate. After accounting for these pathways reflecting oxidative stress, a strong direct path remained from time from first occlusion → organic hydroperoxide production.

Conclusions Peroxidation of lipids in the brain occurs under conditions of severe hypoxia and reperfusion associated with intermittent umbilical cord occlusions of 60 seconds or longer. The path analysis supported the causal model as originally defined, with the exception that the indirect pathway via pH was found to be trivial.

Objectives To summarise the available epidemiological evidence regarding the relationship between the use of progestogen-only contraceptives and bone mineral density.

Design and methods Overview of the published epidemiological literature.

Results Overall, 17 studies of the use of progestogen-only contraceptives and bone mineral density were identified, involving 1529 women exposed to progestogen-only contraceptives and 2086 controls. Sixty-eight percent of the data relate to the effects of use of depot medroxyprogesterone acetate. Average bone mineral density was reduced in current users of depot medroxyprogesterone acetate compared with non-users, although density in users was within one standard deviation of the mean in non-users. There was significant heterogeneity between the results of different studies (P<0.0001). The reduction in bone mineral density appeared to be greater at the lumbar spine, femoral neck and ultradistal forearm than at the midshaft of the ulna. Studies involving women with a longer average duration of use of depot medroxyprogesterone acetate displayed greater reductions in bone mineral density compared with studies of women with shorter durations of use. Based on limited data, no difference in bone mineral density was observed between former and never users of depot medroxyprogesterone acetate. Results regarding the effect of levonorgestrel implants were conflicting. Studies of progestogen-only oral contraceptives and the progesterone vaginal ring were small and restricted to lactating women.

Conclusions Women currently using depot medroxyprogesterone acetate have a lower average bone mineral density than non-users. The magnitude of this effect is uncertain but appears to be greater with longer durations of use.

Objective To compare the efficacy and safety of vaginal misoprostol (50μg) with vaginal dinoprostone.

Design Double-blind randomised trial.

Setting Obstetrics Department, Poissy Hospital, France.

Participants 370 patients with medical indications for induction of labour.

Outcome measures Vaginal deliveries within 24 hours, as well as time to vaginal deliveries, caesarean rates, costs, and fetal, neonatal and maternal condition.

Results Compared with vaginal dinoprostone, vaginal misoprostol resulted in greater efficacy in several areas: vaginal delivery within 24 hours; time to vaginal delivery; and vaginal delivery within 12 hours. There was a non-significant increase in the caesarean section rate for fetal distress in the misoprostol group, but fewer caesarean sections for failed induction. Fetal tolerance was similar in the two groups, although significantly more neonates had a cord pH <7.20 and (non-significantly) none had meconium stained amniotic fluid in the misoprostol group. The incidence of poor neonatal outcome was similar in both groups. Subgroup analysis by indication for induction showed that the higher rates of arterial cord pH <7.20 and of meconium-stained amniotic fluid with misoprostol persisted only in possible fetal compromise. Poor neonatal outcome was less frequent in the misoprostol group in cases of induction for non-fetal indications.

Conclusions Vaginal misoprostol resulted in successful and earlier induction of labour more often than dinoprostone, but the safety of misoprostol raises some concern in potentially compromised infants. Misoprostol should be preferred to dinoprostone in cases of induction for non-fetal indications.