Effect of Stanozolol on Factors VIII and IX and Serum Aminotransferases in Haemophilia

The treatment of haemophilia has been dramatically improved since the introduction of factor VIII and IX concentrates, however these concentrates have brought new problems such as hepatitis and A.I.D.S. An oral agent which could raise endogenous levels of factor VIII and IX would be of great benefit. Danazol, an anabolic steroid, has recently been shown to increase levels of factors VIII and IX in haemophilia. We therefore studied the effect of stanozolol, a closely related anabolic steroid, in 15 patients with haemophilia A or Christmas disease over a 2-4 week period. There was no consistent change in factor VIIIc or factor IX, and fibrinolysis was significantly enhanced. No effect was apparent on the incidence of spontaneous bleeds. However serum aminotransferases which were abnormal in 11 of the 15 patients at the start of the study fell significantly with stanozolol therapy. This raises the interesting possibility that anabolic steroids may be beneficial in patients with chronic liver diseases.

Risk Factors for Pregnancy Associated Venous Thromboembolism

In an attempt to reduce the incidence of pregnancy associated venous thromboembolism (PA-VTE), some researchers have advocated screening of all women for the factor VLeiden mutation during early pregnancy. We have conducted a large retrospective study (over 72,000 deliveries) to determine if this would be useful. Sixty-two objectively confirmed venous thrombotic events (51 DVT, 11 PE) were recorded at two maternity units in the UK. The incidence of DVT was 0.71 per 1000 deliveries (95% CI 0.5-0.9) with 0.50 occurring in the antenatal period (95% CI 0.34-0.66) and 0.21 in the puerperium (95% CI 0.11-0.31). The incidence of PE was 0.15 per 1000 deliveries (95% CI 0.06-0.24), 0.07 antenatal (95% CI 0.01-0.13) and 0.08 in the puerperium (95% CI 0.02-0.14). Of these 62,50 attended for follow-up and thrombophilia screening. 28% of all episodes of PA-VTE had no CIinical risk factor for thrombosis or an identifiable thrombophilic abnormality. Deficiency of antithrombin was identified in 12% of individuals (95% CI 3-21) and the factor VLeiden mutation in 8% (95% CI 0.5-15.5). Based on estimates of the prevalence of the factor VLeiden mutation in the population, we estimate that the thrombotic risk for a woman during pregnancy or the puerperium with the defect is approximately 1 in 400-500. This figure would not lend support to the idea of random screening for the mutation in early pregnancy.

Haemostatic Effects of Ketorolac with and without Concomitant Heparin in Normal Volunteers

Ketorolac is a potent cyclo-oxygenase inhibitor used for the treatment of postoperative pain. It is known to have anti-platelet properties. The aim of this study was to determine the effect of ketorolac on haemostasis both alone and in combination with tow dose heparin in LZ healthy male volunteers. Each volunteer received the following drug combinations in a double blind, placebo controlled, cross over manner: ketorolac placebo/heparin placebo, ketorolac active/heparin placebo, ketorolac active/heparin active and ketorolac placebo/heparin active. Ketorolac significantly prolonged bleeding time, inhibited platelet aggregation to arachidonic acid and collagen and platelet thromboxane production. Heparin had no effect on bleeding time or platelet function, but significantly prolonged the kaolin cephalin clotting time and increased anti-Xa levels. Ketorolac had no effect on the kaolin cephalin clotting time or anti-Xa levels and no interaction was found between ketorolac and heparin in any of the investigations. The prolongation of bleeding time seen with ketorolac is unlikely, to be of any major clinical significance as almost all subjects remained within the normal range; however, it should be used with caution in subjects with haemostatic problems.

Thromboprophylaxis following Caesarean Section

Pharmacological thromboprophylaxis is increasingly being used after caesarean section to prevent venous thromboembolism. Although a variety of low molecular weight heparins (LMWH) have been used no comparative study exists on their effects on the haemostatic system in this situation. Furthermore, their antithrombotic effect may be mediated through effects other than their inhibitory effect on activated factor X. We compared the plasma anti-factor Xa activity, plasma concentration of tissue factor pathway inhibitor (TFPI) and the reduction in plasma thrombin-antithrombin (TAT) complex concentration in 30 women randomised to receive either dalteparin 5,000 IU anti-Xa once daily (n = 10), enoxaparin 4,000 IU anti-Xa once daily (n = 10) or tinzaparin 50 IU/kg anti-Xa (average dose 3,650 anti-Xa units) once daily (n = 10) following caesarean section. Sampling occurred at 0, 1, 3, 6, 12 and 24 h relative to time of dosing. All preparations produced an increase in mean anti-Xa assay (p <0.0001), a reduction in mean TAT (p <0.05) and an increase in mean TFPI concentration (p <0.05). Analysis of variance (ANOVA) revealed a significant difference between the LMWHs in terms of mean anti-factor Xa activity (p <0.005) and reduction in plasma TAT concentration (p <0.005). Post hoc analysis indicated that the anti-Xa values of the groups receiving enoxaparin and dalteparin were significantly higher than those of the group receiving tinzaparin (p <0.05), but not significantly different from each other. Post hoc analysis of the reduction in plasma TAT concentration showed the reduction to be significantly less in the group receiving enoxaparin compared to the dalteparin and tinzaparin groups (p <0.05), which did not differ significantly from each other. There was no significant difference between treatment groups with regard to plasma concentration of TFPI. These findings demonstrate that LMWHs differ in their effects on haemostatic parameters including thrombin generation as assessed by TAT. The increase in TFPI may be an additional mediator of LMWH’s antithrombotic effects. Although these findings demonstrate that LMWHs differ in their haemostatic effects, this does not necessarily infer a clinical difference between these agents.

Superficial Vein Thrombosis: Incidence in Association with Pregnancy and Prevalence of Thrombophilic Defects

Superficial venous thrombotic (SVT) events are a feature of thrombophilic abnormalities, particularly those involving the protein C pathway. We have determined the incidence of SVT associated with pregnancy and the early postpartum period in a retrospective study involving 72 000 deliveries. Fourty-nine cases occurring in 47 individuals were recorded, with an overall incidence of 0.68/1000 deliveries (95% CI 0.48-0.88). None had a previous history of deep vein thrombosis or pulmonary embolism. Most events occurred in the early post-partum period (0.54/1000 deliveries). Twenty-four/fourty-seven were screened for established thrombophilic abnormalities, with only 1 abnormality detected (FVLeiden heterozygote). Thrombophilia may play a minor role in the aetiology of SVT associated with pregnancy, although a larger study is required to confirm this.

Activated Protein C Sensitivity, Protein C, Protein S and Coagulation in Normal Pregnancy

A prospective study of activated protein C sensitivity, protein C, protein S, and other coagulation factors in 239 women during normal pregnancy was carried out. Protein C activity appeared unaffected by gestation, although an elevation of protein C activity was observed in the early puerperium. A fall in total and free protein S with increasing gestation was observed. Activated protein C sensitivity ratio (APC:SR) showed a progressive fall through pregnancy. This fall correlated with changes in factor VIIIc, factor Vc and protein S. 38% of subjects, with no evidence of Factor V Leiden or anticardiolipin antibodies, showed a low APC:SR (APC:SR <2.6) in the third trimester of pregnancy. Aside from a significant reduction in birth weight, no difference in pregnancy outcome was observed between these subjects and those with a normal APC:SR. Activated protein C sensitivity ratio, modified by pre-dilution of patient samples with factor V depleted plasma, showed no consistent trend with gestation.

The influence of maternal Lewis, Secretor and ABO(H) blood groups on fetal growth restriction

BACKGROUND

Fetal growth restriction (FGR) is associated with thrombosis of the placenta and an increased risk of subsequent vascular disease in the mother and fetus. The products of interactions between ABO(H), Lewis and Secretor genes are also associated with thrombosis and vascular disease risk.

OBJECTIVES/METHODS

A prospective case-control study of mothers with a severe FGR pregnancy (cases, n = 128; controls, n = 288) was performed to determine whether FGR is associated with particular maternal blood groups.

RESULTS

No association with ABO(H) status was observed, but FGR was more common in maternal secretors (odds ratio [OR] 1.70, 95% confidence interval [CI] 1.08-2.69) and consequently in those mothers expressing Le(b) on their red cells (OR 1.80, 95% CI 1.15-2.83), with a reduced risk in non-secretors and those expressing Le(a). Given the association between blood groups and both activated protein C resistance (APCR) and von Willebrand factor (VWF) levels, post hoc pilot studies on first-trimester APCR and VWF antigen levels and blood group genotypes were performed. No relationship with Lewis or Secretor was observed. Despite this, lower first-trimester VWF levels were observed in pregnancies subsequently complicated by FGR.

CONCLUSIONS

 This is the first study reporting a relationship between maternal Secretor/Lewis status and FGR. A link between blood groups and FGR is plausible, as both are associated with cardiovascular disease. We observed no relationship between Lewis/Secretor status and VWF or APCR, but this should be confirmed in a larger study. Thus, the mechanism whereby Secretor and/or Lewis influences FGR is unknown.

Antithrombotic treatment for recurrent pregnancy loss?

BACKGROUND

Recurrent pregnancy loss (RPL) is a major issue for women's health. Acquired and heritable thrombophilias are associated with RPL, this association could reflect a general prothrombotic phenotype rather than a specific thrombophilia. Antithrombotic intervention has therefore been assessed for RPL.

RESULTS

Two large randomised trials with untreated control groups showed no benefit from antithrombotic treatment with LMWH and low dose aspirin in women with RPL. These trials had insufficient power to exclude an effect in women with underlying thrombophilia, ≥ 3 losses, or late losses.

CONCLUSIONS

Antithrombotic intervention should not be recommended for unexplained RPL in general. There may be specific groups such as those with an heritable thrombophilia, or with three or more losses, or second trimester losses that might benefit and where further trials are required. Further there is a need to consider the benefits of LMWH on implantation such as in women undergoing assisted conception therapy.

Fetal corticotrophin-releasing hormone mRNA, but not phosphatidylserine-exposing microparticles, in maternal plasma are associated with factor VII activity in pre-eclampsia

BACKGROUND

Pre-eclampsia is associated with increased placental debris circulating in maternal plasma.

OBJECTIVES

This study related placental debris to maternal markers of coagulation and endothelial activation in pre-eclampsia.

PATIENTS/METHODS

Circulating fetal corticotrophin-releasing hormone (CRH) mRNA and phosphatidylserine (PS)-exposing microparticles were assayed in third trimester plasma from women with pre-eclampsia (n = 32) and controls (n = 32) matched for age, body mass index, parity, and gestational age at sampling. Markers of maternal hemostasis and endothelial function were assessed.

RESULTS

Fetal CRH mRNA levels were higher in pre-eclampsia [mean 0.75 (SD 2.77) CRH/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA ratio] than in control pregnancies [0.20 (0.74), P = 0.014]. PS-exposing microparticle levels were not different between the groups. Women with pre-eclampsia had higher levels of tissue factor pathway inhibitor (TFPI), prothrombin F(1+2) fragment (F(1+2)), factor XIIa, soluble vascular cell adhesion molecule 1, von Willebrand factor and plasminogen activator inhibitor 1 than controls. Fetal CRH mRNA correlated with TFPI in pre-eclampsia and control groups (r = 0.38, P = 0.031, and r = 0.37, P = 0.039, respectively). Fetal CRH mRNA correlated with FVII activity (r = 0.43, P = 0.017) and PS-exposing microparticles correlated inversely with F(1+2) (r = -0.64, P < 0.001) in pre-eclampsia.

CONCLUSIONS

Placental debris, assessed by fetal CRH mRNA levels in maternal blood, is related to coagulation potential, i.e. FVII activity, but not to markers of coagulation or endothelial activation in pre-eclampsia.

The parturient with coronary heart disease

Cardiac disease is one of the leading indirect causes of maternal mortality in the UK, exceeding numbers of direct deaths from thromboembolism and hypertension combined. Over one year in our unit we managed six women with coronary heart disease. In this series five women had stable coronary heart disease. Three delivered electively by caesarean section under combined spinal-epidural anaesthesia, a further two women had spontaneous vaginal deliveries, one planned under epidural analgesia, the second unplanned after a rapid labour. The sixth woman had unstable angina requiring percutaneous coronary intervention in the 28th week of pregnancy and went on to deliver by caesarean section under general anaesthesia. Regional anaesthesia was avoided in this case because of antiplatelet and anticoagulant medication. There is a lack of level-one evidence to direct the management of these women. Clinical decisions were directed by guidelines for the perioperative management of patients with cardiac disease in non-cardiac surgery and the management of all cardiac disease in the obstetric population. A multi-disciplinary approach was taken, with a collaborative plan made for each pregnancy and delivery. A thorough clinical history and examination together with transthoracic echocardiography allows risk stratification of women with coronary heart disease at risk of peripartum cardiac events. Further investigation specific to each woman's management can then be undertaken.

The effect of graduated compression stockings on blood velocity in the deep venous system of the lower limb in the postnatal period

Venous thromboembolism (VTE) is the leading cause of maternal mortality in the UK and is also a major cause of long-term morbidity. Recent UK national guidelines recommend thromboprophylaxis, which includes the use of graduated compression stockings (GCS), for high-risk women to reduce the risk of VTE in both the antenatal and postpartum period. This study of 17 women examined the effects of GCS on the deep venous system in the immediate postpartum period and found a statistically significant reduction in the diameter of the common femoral vein (CFV) (pre- versus post stocking diameter: mean 10.39 mm [SD 2.09] versus mean 9.69 mm [SD 1.99]) and an increase in the rate of blood velocity in the CFV (pre- versus post stocking velocity: mean 10.0 cm/s [SD 2.7] versus 13.9 cm/s [SD 4.2]) 30 minutes after application of thigh length GCS in women 1 or 2 days following a singleton vaginal delivery at term. This confirms reduction in venous stasis in the deep venous system in the immediate postpartum woman by the use of GCS, supporting their use in improving venous function in this context.

Thrombophilia in pregnancy: a systematic review

Growing evidence suggests that thrombophilia is associated with venous thromboembolism (VTE) and adverse pregnancy outcomes. However, methodological limitations have made it difficult to obtain a clear overview of the overall risks. We conducted a systematic review to determine the risk of VTE and adverse pregnancy outcomes associated with thrombophilia in pregnancy. The effectiveness of prophylactic interventions during pregnancy was also evaluated. Major electronic databases were searched, relevant data abstracted and study quality assessed by two independent reviewers. Odds ratios (ORs) stratified by thrombophilia type were calculated for each outcome. A total of 79 studies were included in our review. The risks for individual thrombophilic defects were determined for VTE (ORs, 0.74-34.40); early pregnancy loss (ORs, 1.40-6.25); late pregnancy loss (ORs, 1.31-20.09); pre-eclampsia (ORs, 1.37-3.49); placental abruption (ORs, 1.42-7.71) and intrauterine growth restriction (ORs, 1.24-2.92). Low-dose aspirin plus heparin was the most effective in preventing pregnancy loss in thrombophilic women (OR, 1.62). Our findings confirm that women with thrombophilia are at risk of developing VTE and complications in pregnancy. However, despite the increase in relative risk, the absolute risk of VTE and adverse outcomes remains low. There is also a lack of controlled trials of antithrombotic intervention to prevent pregnancy complications. Thus, at present, universal screening for thrombophilia in pregnancy cannot be justified clinically.

The role of factor V Leiden in maternal health and the outcome of pregnancy

There is growing evidence that women with thrombophilia are at increased risk of pregnancy related venous thromboembolism and of adverse pregnancy outcome including pregnancy loss, pre-eclampsia, intrauterine growth retardation and placental abruption. The factor V Leiden mutation is a heritable thrombophilia present in 5-8% of Caucasian populations. In its heterozygous form it is associated with a 4-to 8-fold increase in thrombotic risk. Homozygous inheritance, however, confers around an 80-fold increase in relative risk of thrombosis. The relationship between factor V Leiden and adverse pregnancy outcome has been studied in the recent literature, however the size of the estimated risks varies between individual studies due to heterogeneity of study design and small sample size in many cases. The management of women with factor V Leiden in pregnancy with low molecular weight heparin has been shown to be both safe and effective in preventing venous thromboembolism and improving pregnancy loss. Large scale, randomised controlled studies are required to confirm these findings. Selective screening for factor V Leiden based on prior venous thromboembolism has been shown to be marginally more cost-effective than universal screening in pregnancy and a recent consensus statement has recommended screening for thrombophilia based on a strong personal or family history of venous thromboembolism. There is now some evidence that placental problems may be associated with factor V Leiden in the fetus. There has also been an observed association between maternal factor V Leiden and fetal or neonatal stroke. These areas require further study and at present there is no evidence-based approach to investigation, prevention or management.

Anaesthetic considerations in a parturient with critical coronary artery disease and a drug-eluting stent presenting for caesarean section

A parturient presented with her first symptoms of coronary artery disease at 18 weeks' gestation. Following an angiogram, a drug-eluting stent was inserted, resulting in resolution of her symptoms. The patient was prescribed anti-platelet medication including clopidogrel. She was delivered by elective caesarean section at 35 weeks under general anaesthesia. The anaesthetic management is discussed and a review of the literature presented.

Fetal cord plasma lipoprotein status in uncomplicated human pregnancies and in pregnancies complicated by pre-eclampsia and intrauterine growth restriction

Maternal lipids have been studied extensively in pre-eclampsia (PE) and intrauterine growth restriction (IUGR) but little is known about fetal lipids. We hypothesised that the maternal lipid perturbations in PE and IUGR pregnancies would result in similar alterations in the fetal lipid profile. We performed a cross-sectional case control study of maternal and fetal (delivery venous cord blood) lipid and lipoprotein concentrations in third trimester uncomplicated pregnancies (n = 81) and in pregnancies complicated by PE (n = 23) or IUGR (n = 17). In uncomplicated pregnancies, fetal log total cholesterol (TC), log triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) levels were significantly affected by mode of delivery. Fetal log TC (r = 0.37, P = 0.02), log TG (r = 0.34, P = 0.04) and TC/HDL-C ratio (r = 0.31, P = 0.05) were positively correlated with placental weight. Maternal TC (r = 0.35, P = 0.03) and LDL levels (r = 0.36, P = 0.02) were associated with fetal HDL-C levels. Maternal TC was significantly elevated in PE [mean 6.75 (standard deviation 1.14) mmol/L] compared to BMI-matched controls [5.94 (0.89) mmol/L P = 0.04]. In PE, fetal log TC [mean 0.36 (0.23) versus 0.11 (0.15) log mmol/L, P = 0.03], fetal log TG [-0.21 (0.32) versus -0.49 (0.26) log mmol/L, P = 0.02] and fetal TC/HDL-C ratio [3.64 (1.62) versus 1.80 (0.86), P = 0.001] were higher than in controls, after adjustment for mode of delivery. In IUGR, fetal log TG [-0.17 (0.35) versus -0.57 (0.10) log mmol/L, P = 0.01] was higher than controls, after adjustment for mode of delivery. There were no correlations between maternal and fetal lipid levels, or between fetal birth weight and either maternal or fetal lipids in the PE or IUGR groups. We conclude that although fetal lipids do not show a direct correlation with maternal lipids in PE or IUGR, these complications of pregnancy significantly impact upon fetal lipid levels possibly due to increased fetal stress or compromised placental lipid transport. Our findings are potentially pertinent to understanding the future cardiovascular health of the offspring.

Low-molecular-weight heparin for the prevention and treatment of venous thromboembolism in pregnancy

PURPOSE OF REVIEW

Low-molecular-weight heparins (LMWHs) have largely replaced unfractionated heparins for both prophylaxis and treatment of venous thromboembolism in nonpregnant patients. However, until recently, evidence in pregnant women was lacking, despite the increasing use of LMWHs during pregnancy in clinical practice. This review covers recent literature on the use of LMWHs in relation to pregnancy.

RECENT FINDINGS

The main areas covered in this review are the use of LMWHs in both prophylaxis and treatment of venous thromboembolism in pregnancy. The review also considers issues relating to monitoring of LMWHs in pregnancy, and safety from both a maternal and a fetal perspective.

SUMMARY

The available evidence demonstrates that LMWHs are of at least equivalent efficacy but have a better safety profile compared with unfractionated heparins in both prophylaxis and treatment of maternal venous thromboembolism, and are more convenient to administer. There is no consensus with respect to whether these agents require monitoring during pregnancy other than periodic checking of the platelet count. The clinical implication from the available evidence is that LMWHs should now be regarded as the anticoagulant agents of choice for both prophylaxis and treatment of maternal venous thromboembolism.

Low molecular weight heparin for the treatment of venous thromboembolism in pregnancy: a case series

OBJECTIVES

To assess the use of low molecular weight heparin for the treatment of venous thromboembolism in pregnancy.

DESIGN

A prospective observational study.

SETTING

The maternity units in two university teaching hospitals and one district general teaching hospital.

POPULATION

Thirty-six consecutive women presenting with objectively diagnosed venous thromboembolism during pregnancy and the immediate puerperium.

METHODS

Treatment with the low molecular weight heparin enoxaparin, approximately 1 mg/kg s.c., twice daily, based on early pregnancy weight.

MAIN OUTCOME MEASURES

Peak anti-Xa activity (three hours post-injection), alterations in treatment, side effects and the use of regional anaesthesia.

RESULTS

In 33 women, the initial dose of enoxaparin provided satisfactory peak anti-Xa activity (median 0.8 u/mL, range 0.44-1.0 u/mL) and was continued. Three women required dose reduction since peak anti-Xa activities were above the therapeutic range (1.2, 1.2 and 1.1 u/mL). No woman developed thrombocytopaenia, haemorrhagic complication or further thromboembolic episode. Two women developed allergic skin reactions on enoxaparin and were changed to tinzaparin. Fifteen women had regional anaesthesia for delivery, with a reduced dose of enoxaparin (40 mg once daily), all without complication.

CONCLUSIONS

Enoxaparin is a safe and effective treatment for venous thromboembolism during pregnancy and confers a major advantage over unfractionated heparin through its simplified regimen of administration.

Ketorolac, diclofenac, and ketoprofen are equally safe for pain relief after major surgery

BACKGROUND

Ketorolac is approved for the relief of postoperative pain but concerns have been raised over a possible risk of serious adverse effects and death. Two regulatory reviews in Europe on the safety of ketorolac found the data were inconclusive and lacked comparison with other non-steroidal anti-inflammatory drugs. The aim of this study was to compare the risk of serious adverse effects with ketorolac vs diclofenac or ketoprofen in adult patients after elective major surgery.

METHODS

This prospective, randomized multicentre trial evaluated the risks of death, increased surgical site bleeding, gastrointestinal bleeding, acute renal failure, and allergic reactions, with ketorolac vs diclofenac or ketoprofen administered according to their approved parenteral and oral dose and duration of treatment. Patients were followed for 30 days after surgery.

RESULTS

A total of 11,245 patients completed the trial at 49 European hospitals. Of these, 5634 patients received ketorolac and 5611 patients received one of the comparators. 155 patients (1.38%) had a serious adverse outcome, with 19 deaths (0. 17%), 117 patients with surgical site bleeding (1.04%), 12 patients with allergic reactions (0.12%), 10 patients with acute renal failure (0.09%), and four patients with gastrointestinal bleeding (0.04%). There were no differences between ketorolac and ketoprofen or diclofenac. Postoperative anticoagulants increased the risk of surgical site bleeding equally with ketorolac (odds ratio=2.65, 95% CI=1.51-4.67) and the comparators (odds ratio=3.58, 95% CI=1.93-6.70). Other risk factors for serious adverse outcomes were age, ASA score, and some types of surgery (plastic/ear, nose and throat, gynaecology, and urology).

CONCLUSION

We conclude that ketorolac is as safe as ketoprofen and diclofenac for the treatment of pain after major surgery.

The acute management of venous thromboembolism in pregnancy

Pulmonary thromboembolism is the leading cause of maternal death in the UK. Optimal management of deep venous thrombosis and pulmonary thromboembolism requires an appreciation of risk factors, particularly thrombophilia, and signs or symptoms suggestive of venous thromboembolism, along with objective diagnosis and treatment with anticoagulants. Low molecular weight heparins are now replacing unfractionated heparin for the treatment of deep venous thrombosis and pulmonary thromboembolism in pregnancy because of the lower risk of side effects, ease of administration and reduced need for monitoring.

The effect of type 1 diabetes mellitus on vascular responses to endothelin-1 in pregnant women

Diabetes is associated with vascular dysfunction, which may be due in part to altered vascular responses to endogenous peptides such as endothelin-1. These altered responses may also contribute to the decreased maternal peripheral resistance in pregnancy. The aim of this study was to examine the effect of diabetes on the vasoconstrictor response to endothelin-1 in pregnant women. Small arteries were isolated from nine healthy pregnant, seven type 1 diabetic pregnant women, and five healthy nonpregnant women. Contraction curves were performed on a wire myograph for noradrenaline (1 nM to 30 microM) and endothelin-1 (1 pM to 0.3 microM). Maximum responses and sensitivity were compared by t test. No differences in maximum response to noradrenaline or potassium were seen among the three groups. The maximum response to endothelin-1 was significantly increased in pregnancy (P < 0.05), whereas endothelin-1 sensitivity was reduced in the diabetic compared with the nondiabetic pregnant women (P < 0.05). Pregnant women have an increased maximum vasoconstriction response to endothelin-1 compared with nonpregnant women, whereas diabetic pregnant women demonstrate reduced sensitivity to endothelin-1. These observations suggest that endothelin-1 may play a role in maintaining peripheral vascular tone in normal pregnancy, and the decreased sensitivity seen in pregnant women with diabetes may reflect abnormal vascular reactivity.

Circulating leptin concentrations and ovarian function in polycystic ovary syndrome

OBJECTIVE

Polycystic ovary syndrome (PCOS) is characterized by ovarian dysfunction. Although the role of leptin in the control of reproduction is unclear, it may be involved in the control of ovulation. The aim of this cross-sectional study was to determine the relationship between circulating leptin concentrations, and anthropometric, metabolic and endocrine variables as well as to examine a possible role of leptin in ovarian dysfunction associated with PCOS.

DESIGN

Prospective observational study.

METHODS

Seventy-one subjects with PCOS and 23 body mass index (BMI)-matched control subjects were recruited from infertility clinics. The association between serum leptin concentrations and the above variables was measured outwith the luteal phase. A subgroup of 24 PCOS subjects underwent more frequent blood sampling to monitor follicular growth and ovulation. The association between variables was measured by univariate, multivariate and partial correlation analyses.

RESULTS

Serum leptin concentrations were not different in subjects with PCOS and controls, and were strongly associated with BMI in both groups. Twelve patients ovulated during the study period. There was no significant difference in serum leptin concentrations between ovulatory and anovulatory subjects. The relationship between BMI and leptin was similar in both groups.

CONCLUSION

The results indicated that circulating leptin concentrations relate principally to total body fat in subjects with PCOS and controls, and that this is not associated with the facility for follicular development and ovulation in these patients.

Management of venous thromboembolism in pregnancy

Pulmonary thromboembolism (PTE) is the major cause of maternal death in the UK, with recent trends showing an increase in the numbers of deaths. Underlying PTE is the problem of deep venous thrombosis (DVT). An appreciation of risk factors, particularly, thrombophilia, and signs or symptoms suggestive of thromboembolism, coupled with objective diagnosis and treatment should reduce mortality and morbidity. There are particular considerations with regard to the management of thrombosis in pregnancy, especially the use of anticoagulants. Low-molecular-weight heparins are now replacing unfractionated heparin for the treatment of DVT and PTE in pregnancy.

Lipids and lipoprotein subfractions in women with PCOS: relationship to metabolic and endocrine parameters

OBJECTIVE

Women with polycystic ovary syndrome (PCOS) exhibit an abnormal lipoprotein profile, characterized by raised concentrations of plasma triglyceride, marginally elevated low density lipoprotein (LDL)-cholesterol, and reduced high density lipoprotein (HDL)-cholesterol. However, a normal LDL-cholesterol level may be misleading since LDL exists as subpopulations of particles differing in size and atherogenic potential. Smaller LDL particles are more atherogenic and high concentrations often occur in association with elevated circulating triglyceride concentrations (but frequently normal total LDL-cholesterol), increased hepatic lipase activity (HL) and insulin resistance. Information on LDL subclasses and HL activity in women with PCOS is sparse. The aim of this study was to determine the concentrations of small, dense LDL (LDL-III) in women with PCOS relative to body mass index (BMI)-matched controls. We also examined the association of lipoprotein subfraction concentrations with endogenous sex hormone concentrations, since existing literature suggested that androgens up-regulate and oestrogens down-regulate HL activity, a key determinant of LDL subfraction distribution.

DESIGN

Cross sectional study.

PATIENTS

Fifty-two women with oligomenorrhoea and polycystic ovaries determined by ultrasound and BMI matched women with normal menstrual rhythm (NMR) and normal ovarian appearances (n = 14) were recruited from gynaecology clinics. Anthropometric data and fasting blood samples were obtained for metabolic, hormonal and LDL subfraction estimation and a heparin provocation test was used to estimate HL activity.

RESULTS

Subjects with PCOS demonstrated higher waist:hip ratio (WHR), testosterone, triglyceride, VLDL-cholesterol concentrations, and HL activity (P < 0.05), whereas SHBG concentrations were significantly lower than controls. PCOS women had higher concentrations (38.0 vs. 25.0 mg/l; P = 0.026) and proportions (12.8 vs. 8.2%; P = 0.006) of small, dense LDL (LDL III), relative to controls. Within the PCOS group, plasma triglyceride and HL activity were the strongest univariate predictors of LDL III mass. They remained as independent predictors in multivariate analysis, and together accounted for 37% of its variability (P = 0.0002). Independent predictors of plasma triglyceride and HL in turn, were measures of fat distribution (waist circumference or WHR) and fasting insulin concentration. Serum testosterone concentration was not associated either in univariate or multivariate analysis with any of the measured lipid, lipoprotein or subfraction parameters, nor with HL activity in the women with PCOS.

CONCLUSION

We conclude that women with polycystic ovary syndrome have increased hepatic lipase activity and mass and percentage of small, dense low density lipoprotein relative to body mass index-matched controls with normal menstrual rhythm and normal ovaries. Further, these metabolic perturbances appear related more closely to adiposity/insulin metabolism than to circulating androgen levels.

Vaginal application of the nitric oxide donor isosorbide mononitrate for preinduction cervical ripening: a randomized controlled trial to determine effects on maternal and fetal hemodynamics

OBJECTIVE

Our aim was to assess the effects of vaginally administered isosorbide mononitrate (a nitric oxide donor) on maternal and fetal hemodynamics in pregnant women at term.

STUDY DESIGN

We conducted a randomized controlled trial. Women were randomly selected to receive vaginally administered isosorbide mononitrate, 20 mg (n = 13) or 40 mg (n = 11), or to undergo a vaginal examination only (n = 12). Maternal pulse, blood pressure, and fetal heart rate were recorded at baseline and then every 30 minutes until 360 minutes. Umbilical artery resistance index and pulsatility index measurements were performed at 0, 180, and 330 minutes.

RESULTS

Maternal pulse rate was greater after the administration of isosorbide mononitrate, 20 or 40 mg, compared with the pulse rate in the vaginal examination-only group (greatest difference in means, 21 beats/min; P <.01). Maternal systolic and diastolic blood pressures were greater in the 20-mg and 40-mg isosorbide mononitrate groups than in the vaginal examination-only group (greatest difference in mean systolic and diastolic blood pressure, 15 and 16 mm Hg, respectively; P <.02 and P <.001, respectively). Fetal heart rate was greater in the 40-mg isosorbide mononitrate group than in either the 20-mg isosorbide mononitrate group or the vaginal examination-only group (difference in mean, 15 beats/min; P <.05). No woman required treatment for maternal or fetal tachycardia or maternal hypotension. Neither dose of isosorbide mononitrate had a significant effect on umbilical artery resistance or pulsatility index.

CONCLUSIONS

Vaginal administration of 20 or 40 mg isosorbide mononitrate to pregnant women at term has an effect on both maternal and fetal hemodynamics, but this effect is not clinically significant.

A comparison of isosorbide mononitrate, misoprostol and combination therapy for first trimester pre-operative cervical ripening: a randomised controlled trial

OBJECTIVE

To determine whether a combined therapy with isosorbide mononitrate (40mg) and misoprostol (400 microg) for pre-operative cervical ripening in the first trimester would result in improved clinical effectiveness, and fewer side effects compared with each agent used alone.

DESIGN

Randomised controlled trial.

SETTING

Glasgow Royal Infirmary.

POPULATION

Sixty-six primigravid women scheduled for suction termination of pregnancy.

METHODS

Women were randomly assigned to receive before surgery, per vaginam, isosorbide mononitrate 40 mg (n = 22), misoprostol 400 microg (n = 22) or both agents together [isosorbide mononitrate 40 mg and misoprostol 400 microg] (n = 22).

MAIN OUTCOME MEASURES

1. To assess the cumulative force required to dilate the cervix to 8 mm; 2. the onset of new symptoms before termination of pregnancy.

RESULTS

The cervical resistance following combination therapy with isosorbide mononitrate and misoprostol was not significantly different than following misoprostol alone [24.5N vs 18.5N; median difference (95% CI) 19N (-22 to 49)]. Pre-treatment with misoprostol used alone resulted in a lower cervical resistance than isosorbide mononitrate alone (18.5N vs 39N, P = 0.04, Mann-Whitney U test). There was no difference in the number of women remaining asymptomatic following either isosorbide mononitrate or misoprostol or combination therapy [14/22 (64%) vs 11/21 (52%) vs 11/22 (50%), Fisher's exact test].

CONCLUSIONS

We have not shown any advantage of combining misoprostol with the nitric oxide donor isosorbide mononitrate compared with misoprostol alone for pre-operative cervical ripening in the first trimester.

Injecting drug use is a risk factor for deep vein thrombosis in women in Glasgow

Three hundred and twenty-two consecutive women aged 16-70 years who presented with objectively confirmed symptomatic venous thromboembolism (VTE) were studied to determine precipitating factors for thrombosis. One hundred and eighty-seven presented with deep vein thrombosis (DVT), 116 with either definite or possible pulmonary embolism (PE) and 19 with both DVT and PE. Injecting drug use (IDU) via femoral vein puncture was a common risk factor for DVT, associated with 21.4% of all cases of DVT and 52.4% of cases of DVT in women under 40 years. All women with drug-related thrombosis presented with DVT. None presented with symptomatic PE. A number of clinically diagnosed DVT associated with IDU were also documented, suggesting that IDU may be the most common risk factor for DVT in our region. DVT associated with IDU presents significant management challenges.

Antenatal waist circumference and hypertension risk

OBJECTIVE

To assess whether waist circumference at the first antenatal visit predicts risk of developing hypertension later in pregnancy.

METHODS

Pregnant women with singleton pregnancies (n = 1142, median age 29 years, interquartile range 25-32 years, 387 primigravidas) were recruited at their first antenatal visits. Using standardized methods, midwives determined the weights, heights (for calculation of body mass index [BMI]), and waist circumferences of all women. Eighty-two women developed pregnancy-induced hypertension, and 21 developed preeclampsia (hypertension with proteinuria).

RESULTS

The median waist circumference between 6 and 16 weeks' gestation was 79 cm (interquartile range 72-84 cm), and there was no significant relationship between waist circumference and gestational age. Greater waist circumference was noted in subjects who subsequently developed pregnancy-induced hypertension (median 81 versus 77 cm, Mann-Whitney U test, P =.002) or preeclampsia (median 80 versus 77 cm, P =.02). The conventional, nonpregnant waist circumference action level of 80 cm gave a Mantel-Haenszel odds ratio (OR) for pregnancy-induced hypertension of 1.8 (95% confidence interval [CI] 1.1, 2.9) and for preeclampsia of 2.7 (95% CI 1.1, 6.8), compared with waists of less than 80 cm. Body mass index values were higher in women who developed pregnancy-induced hypertension (median 26 versus 24, P =.001) or preeclampsia (median 26 versus 24, P =.02). The conventional action limit for a BMI of 25 had an OR for pregnancy-induced hypertension of 2.0 (95% CI 1.2, 3.4) and for preeclampsia of 1.9 (95% CI 0.7, 4.8). Results were similar when the analysis was restricted to data from primigravidas.

CONCLUSION

We conclude that waist circumference up to 16 weeks' gestation can predict pregnancy-induced hypertension and preeclampsia. Therefore, waist circumference could form the basis for health promotion involving raising awareness of the importance of or urging weight reduction for women planning pregnancies.

The Glasgow Outcome, APCR and Lipid (GOAL) Pregnancy Study: significance of pregnancy associated activated protein C resistance

Activated protein C (APC) resistance secondary to Factor V Leiden (FVL) is associated with pregnancy failure and pre-eclampsia (PET). In non-pregnant subjects, the degree of resistance to APC relates to venous thrombosis risk. In pregnancy, resistance to APC occurs in the absence of FVL. We investigated, in an unselected prospective longitudinal study of 1,671 pregnant, non-FVL subjects, the relationship of the APC sensitivity ratio (APC:SR) with demographic variables and pregnancy outcome. Lower APC:SR values at 7-16 weeks gestation were observed in subjects who subsequently developed PET (median APC:SR 2.55, IQR 2.29-2.70 vs 2.69, IQR 2.48-2.93, Mann-Whitney U-test p = 0.003) in the current pregnancy. An APC:SR < the median (2.69) at 7-16 weeks was associated with a 2.95-fold increased risk (CI95 1.2-7.4) of PET in the current pregnancy. No relationship between the APC:SR, at any gestation, and fetal loss was observed. An inverse correlation between the APC:SR and birth weight was noted. Higher APC:SRs were observed in blood group O subjects and smokers. An inverse relationship of the APC:SR with age, diastolic blood pressure and total serum cholesterol was observed.

Changes in the expression of nitric oxide synthase in the human uterine cervix during pregnancy and parturition

Nitric oxide (NO) has been proposed as a mediator of cervical ripening. We investigated the expression, using Western blotting, and localization, using immunohistochemistry, of the nitric oxide synthase (NOS) enzymes, inducible NOS (iNOS), endothelial NOS (eNOS) and neuronal NOS (bNOS) in the human cervix during pregnancy and parturition. Cervical biopsies were obtained from non-pregnant women, women in the first trimester of pregnancy, and pregnant women at term before and after the onset of labour. Each of the NOS isoforms was localized in the cervices of both non-pregnant and pregnant subjects using immunohistochemistry. iNOS expression was significantly greater in early pregnancy compared with the non-pregnant state (P: < 0.005). iNOS expression was up-regulated further in samples obtained in the third trimester compared with the first trimester. bNOS expression was greater in samples from the first trimester of pregnancy than in non-pregnant samples (P: < 0. 005), but showed no additional increase in late pregnancy or with the onset of labour. eNOS expression was increased in samples obtained in the third trimester both before (P: = 0.002) and after the onset of labour (P: < 0.002) when compared with non-pregnant samples. The increased expression of NOS isoforms in late pregnancy supports the hypothesis that NO is involved in the process of cervical ripening.

The special case of venous thromboembolism in pregnancy

Pulmonary thromboembolism remains a major cause of maternal death in the Western world. The frequency of antepartum deaths, including deaths in the first and second trimester, which can be associated with early pregnancy problems such as hyperemesis, is similar in number to the deaths occurring following delivery. Risk factors for deep vein thrombosis have been identified and include age > 35 years, operative delivery (particularly emergency Caesarean section), obesity and a personal or family history of thrombosis or thrombophilia. These risk factors should be used to guide administration of thromboprophylaxis during both pregnancy and the post-partum period, particularly after Caesarean section. Specific consideration towards thromboprophylactic agents is required. Warfarin crosses the placenta, is a known teratogen when used in early pregnancy and can also be associated with bleeding problems in the foetus, particularly at the time of delivery. Thus, warfarin has a limited use in the antenatal period and is usually only employed in patients such as those with artificial heart valves who require long-term anticoagulation. However, as warfarin does not cross the breast in any significant amount, it is suitable during breast feeding. In contrast, heparin does not cross the placenta or the breast therefore foetal problems are not associated with this treatment. However, heparin can be associated with problems such as heparin-induced osteoporosis, allergy and heparin-induced thrombocytopenia. The risk of some of these complications can be reduced by the use of low-molecular-weight heparins. When venous thromboembolism is suspected in pregnancy, it is critically important to obtain an objective diagnosis. This will include real-time or duplex ultrasound scan of the legs to elaborate the venous system, ventilation perfusion lung scan and, occasionally, venography. Treatment of established venous thromboembolism is similar to that in the non-pregnant patient and it is likely that low-molecular-weight heparins will play a major role in thromboprophylaxis in the future.