Primary, secondary, and tertiary prevention of pre-eclampsia

Reduced maternal corticosteroid-binding globulin and cortisol levels in pre-eclampsia and gamete recipient pregnancies

OBJECTIVE

To measure and contrast maternal cortisol and corticosteroid-binding globulin (CBG) levels in pregnancies with normal outcomes, pre-eclampsia, intrauterine growth restriction (IUGR) and in gamete recipients.

STUDY DESIGN

Prospective study of 93 women at high risk of pre-eclampsia, including gamete recipients (n = 22) and 33 controls. Plasma total and free cortisol and CBG were measured every 2 weeks from 16 weeks' gestation until delivery.

RESULTS

Forty-two per cent of the high-risk group had complications, including pre-eclampsia (n = 11), gestational hypertension (n = 16) and small-for-gestational-age (SGA) neonates (n = 12). There were no complications in the controls. In all groups, plasma CBG concentrations increased progressively across gestation (P < 0.05), in parallel to total cortisol, but fell significantly from 36 weeks' gestation onwards, with a corresponding rise in free cortisol concentrations. In pre-eclampsia and gestational hypertension, plasma CBG, and total and free cortisol concentrations were lower from 36 weeks onwards (P < 0.05). In IUGR, plasma CBG concentrations were suppressed from 28 weeks' gestation until delivery (P < 0.05), but with no significant difference in plasma total and free cortisol. Gamete recipients had significantly lower plasma CBG from 20 weeks' gestation onwards, and plasma total and free cortisol were reduced at 24 and 32 weeks onwards, respectively.

CONCLUSIONS

Maternal plasma CBG, total and free cortisol concentrations are reduced in pre-eclampsia/gestational hypertension, and markedly reduced in gamete recipients. Low CBG may be due to reduced synthesis or enhanced inflammation-driven degradation. Low maternal cortisol may be due to a lack of placental corticotropin-releasing hormone or reduced maternal ACTH, driving cortisol production. Low maternal cortisol may influence the foetal hypothalamic-pituitary-adrenal axis and disease patterns later in life following complicated pregnancy.

Could antioxidant supplementation prevent pre-eclampsia?

Pre-eclampsia is a disorder characterised by pregnancy-induced hypertension and new-onset proteinuria occurring in the second half of pregnancy. Worldwide, approximately 2–3% of all pregnant women develop pre-eclampsia. The condition is a major cause of maternal and fetal morbidity and mortality. Abnormal placentation is an important predisposing factor for pre-eclampsia, while endothelial activation appears to be central to the pathophysiological changes, possibly indicative of a two-stage disorder characterised by reduced placental perfusion and a maternal syndrome. There is increasing evidence that pre-eclampsia is associated with both increased oxidative stress and reduced antioxidant defences, which has led to the hypothesis that oxidative stress may play an important role in the pathogenesis of pre-eclampsia, perhaps acting as the link in a two-stage model of pre-eclampsia. In support of this hypothesis a small, but important, preliminary study has shown a highly significant (P= 0.02) reduction in the incidence of pre-eclampsia in women at risk who were taking a supplement of vitamins C and E from mid-pregnancy. Furthermore, these findings support the hypothesis that oxidative stress is at least partly responsible for the endothelial dysfunction of pre-eclampsia. Several larger multicentre trials are currently underway to evaluate the efficacy, safety and cost benefits of antioxidant supplementation during pregnancy for the prevention of pre-eclampsia in both low- and high-risk women, including women with diabetes. The results of these trials are awaited with interest.

Prepregnancy Body Mass Index and the Occurrence of Severe Hypertensive Disorders of Pregnancy

BACKGROUND

Prepregnancy overweight is a risk factor for mild preeclampsia and mild transient hypertension of pregnancy. Its association with severe subtypes of these disorders has received less attention.

METHODS

To assess the association of prepregnancy body mass index (BMI) with severe and mild preeclampsia and transient hypertension of pregnancy, we used data from a 1958-1964 prospective cohort study of 38,188 pregnant women receiving care at 12 U.S. hospitals.

RESULTS

There was a monotonic, dose-response relation between prepregnancy BMI and risk of both severe and mild preeclampsia, as well as the risk of severe and mild transient hypertension of pregnancy. Compared with white women with a BMI of 20, the odds ratios for severe preeclampsia at BMI values of 25 and 30 in white women were 1.7 (95% confidence interval = 1.1-2.5) and 3.4 (2.1-5.6), respectively, and 2.1 (1.4-3.2) and 3.2 (2.1-5.0) in black women. The effect of BMI on risk of severe preeclampsia was similar to its effect on mild disease. Compared with the same referent, odds ratios for severe transient hypertension of pregnancy at BMI values of 25 and 30 in white women were 3.6 (2.0-6.5) and 8.8 (4.4-18), respectively, and 3.0 (1.6-5.8) and 4.9 (2.5-9.6) in black women. Overweight was a stronger risk factor for severe than for mild transient hypertension.

CONCLUSIONS

Incidence of both mild and severe hypertensive disorders of pregnancy rises with increasing BMI. Escalating obesity rates may increase pregnancy hypertensive disorders and ensuing perinatal morbidity.

Association Between Maternal Periodontitis and an Increased Risk of Preeclampsia

BACKGROUND

Periodontal disease has been considered a systemic exposure implicated in a higher risk of adverse pregnancy outcomes. The aim of the present study was to determine whether maternal periodontitis is associated with an increased risk of preeclampsia.

METHODS

A case-control study was conducted in a public hospital in Belo Horizonte, Brazil. During the study period, 588 women, aged 14 to 46 years, were deemed eligible and had data available for analysis. Maternal demographic and medical data were collected from medical records. Preeclampsia was defined as blood pressure >140/90 mm Hg and > or =1+ proteinuria after 20 weeks of gestation. A periodontal examination was performed postpartum. Maternal periodontitis was defined as the presence of four or more teeth with one or more sites with a probing depth > or =4 mm and clinical attachment loss > or =3 mm at the same site. The effects of maternal age, chronic hypertension, primiparity, smoking, alcohol use, and number of prenatal visits were analyzed. Adjusted odds ratios (ORs) for preeclampsia were calculated using multivariate logistic regression.

RESULTS

The prevalence of periodontitis was 63.9% and preeclampsia was 18.5%. Variables associated with preeclampsia were chronic hypertension (OR = 4.10; 95% confidence interval [CI] = 2.0 to 8.4; P = 0.001), primiparity (OR = 2.40; 95% CI = 1.5 to 3.9; P = 0.004), maternal age (OR = 1.07; 95% CI = 1.0 to 1.1; P = 0.001), and maternal periodontitis (OR = 1.88; 95% CI = 1.1 to 3.0; P = 0.001).

CONCLUSION

Maternal periodontitis was determined to be associated with an increased risk of preeclampsia.

Identification of two novel quantitative trait loci for pre-eclampsia susceptibility on chromosomes 5q and 13q using a variance components-based linkage approach

Pre-eclampsia/eclampsia (PE/E) is a common and serious disorder of human pregnancy that is associated with substantial maternal and perinatal morbidity and mortality. The suspected aetiology of PE/E is complex, with susceptibility being attributable to multiple environmental factors and a large genetic component. By assuming that the underlying liability towards PE/E susceptibility is inherently quantitative, any PE/E susceptibility gene would represent a quantitative trait locus (QTL). This assumption enables a more refined and powerful variance components procedure using a threshold model for our PE/E statistical analysis. Using this more efficient linkage approach, we have now re-analysed our previously completed Australian/New Zealand genome scan data to identify two novel PE/E susceptibility QTLs on chromosomes 5q and 13q. We have obtained strong evidence of linkage on 5q with a peak logarithm-of-odds (LOD) score of 3.12 between D5S644 and D5S433 [at approximately 121 centimorgan (cM)] and strong evidence of linkage on 13q with a peak LOD score of 3.10 between D13S1265 and D13S173 (at approximately 123 cM). Objective identification and prioritization of positional candidate genes using the quantitative bioinformatics program GeneSniffer revealed highly plausible PE/E candidate genes encoding aminopeptidase enzymes and a placental peptide hormone on the 5q QTL and two type IV collagens on the 13q QTL regions, respectively.

Prediction of pre-eclampsia: a protocol for systematic reviews of test accuracy

BACKGROUND

Pre-eclampsia, a syndrome of hypertension and proteinuria, is a major cause of maternal and perinatal morbidity and mortality. Accurate prediction of pre-eclampsia is important, since high risk women could benefit from intensive monitoring and preventive treatment. However, decision making is currently hampered due to lack of precise and up to date comprehensive evidence summaries on estimates of risk of developing pre-eclampsia.

METHODS/DESIGN

A series of systematic reviews and meta-analyses will be undertaken to determine, among women in early pregnancy, the accuracy of various tests (history, examinations and investigations) for predicting pre-eclampsia. We will search Medline, Embase, Cochrane Library, MEDION, citation lists of review articles and eligible primary articles and will contact experts in the field. Reviewers working independently will select studies, extract data, and assess study validity according to established criteria. Language restrictions will not be applied. Bivariate meta-analysis of sensitivity and specificity will be considered for tests whose studies allow generation of 2 x 2 tables.

DISCUSSION

The results of the test accuracy reviews will be integrated with results of effectiveness reviews of preventive interventions to assess the impact of test-intervention combinations for prevention of pre-eclampsia.

Outcomes of subsequent pregnancy after first pregnancy with early-onset preeclampsia

OBJECTIVE

The aim of this study was to report outcome of subsequent pregnancy after early-onset preeclampsia in first pregnancy, and to evaluate potential risk factors for recurrence of preeclampsia and preterm delivery.

STUDY DESIGN

Reproductive follow-up data were obtained for women with a history of early-onset preeclampsia, resulting in delivery before 34 weeks of gestation at the University Medical Center Utrecht, The Netherlands, between July 1993 and September 2002. The relative contributions of demographic data, outcome variables of first pregnancy, and common thrombophilias to the recurrence risk of preeclampsia and preterm delivery in subsequent pregnancy, were estimated by Cox proportional hazard models.

RESULTS

Subsequent pregnancy outcome data were available for 120 women. Overall, preeclampsia reoccurred in the second pregnancy in 30 women (25%). However, 6 women delivered before 34 weeks of gestation (5%), 20 women between 34 and 37 weeks of gestation (17%), and 94 women after 37 weeks of gestation (78%). Forty-one women (34%) had an uneventful pregnancy. Recurrence rates for preeclampsia or preterm delivery were not related to severity of first pregnancy complications, including delivery before 28 weeks of gestation, occurrence of hemolysis, elevated liver enzymes, and low platelet count syndrome, small-for-gestational age infants, and to hereditary or acquired thrombophilias. Chronic hypertension was related to a higher recurrence risk of preeclampsia in the second pregnancy (hazard ratio 2.1, 95% CI 1.0-4.4), and smoking was related to a higher recurrence risk of preterm birth (hazard ratio 2.4, 95% CI 1.1-5.6).

CONCLUSION

Outcomes of subsequent pregnancy after first pregnancy with early-onset preeclampsia is generally favorable.

Risk factors for pre-eclampsia in Lagos, Nigeria

BACKGROUND

Pre-eclampsia is an important cause of maternal mortality. Although there have been many studies worldwide on pre-eclampsia, not many have come from black Africa.

STUDY DESIGN

A case-control study was conducted in a tertiary hospital in Nigeria (the black African nation with the highest population) between February 2001 and August 2002 to determine the risk factors for eclampsia. Information on socio-demographic characteristics, pre-pregnancy weight, medical history and previous obstetric history, and level of stress at home and at work was obtained by face-to-face interviews.

ANALYSIS

Multiple logistic regression analysis was used to determine the risk factors for pre-eclampsia.

RESULTS

One hundred and thirty seven (7.6%) of the 1803 women who delivered during the period had pre-eclampsia/eclampsia. Of these, 128 (93.4%) were analysed. Ninety-one (71.1%) women were primigravidae. Age < or = 19 years was not considered a risk factor. The risk factors that were associated with increased risk of pre-eclampsia were: nulliparity (OR 4.77; 95% CI 2.90-7.78), stressful work during pregnancy (OR 2.10; 95% CI 1.20-3.71), stressful home environment (OR 1.97; 95% CI 1.27-3.69), previous pre-eclampsia (OR 11.68; CI 3.81-37.61), history of chronic hypertension (OR 2.21; 95% CI 1.17-6.20), a body weight greater than 80 kg (OR 2.01; 95% CI 1.05-3.87); and multiple pregnancy (OR 2.71; 95% CI 1.27-6.13).

CONCLUSIONS

Risk factors for pre-eclampsia among Nigerian women are not different from those that have been reported in other studies. Weight reduction, good control of chronic hypertension, and reduction of stressful conditions at home and in pregnancy could be steps towards the primary prevention of this disorder.

Increased risk of pre-eclampsia and fetal death in HIV-infected pregnant women receiving highly active antiretroviral therapy

BACKGROUND

Pre-eclampsia and/or fetal death have increased sharply in HIV-infected pregnant women receiving HAART.

METHODS

The occurrence of pre-eclampsia or fetal death was analysed in women who delivered after at least 22 weeks of gestation for all women (January 2001 until July 2003) and for HIV-infected women (November 1985 until July 2003).

RESULTS

In 2001, 2002 and 2003, the rates per 1000 deliveries of pre-eclampsia and fetal death, respectively, remained stable in all pregnant women at 25.4, 31.9 and 27.7 (P = 0.48) and 4.8, 5.8, and 5.0 (P = 0.89) (n = 8768). In 1985-2000 (n = 390) to 2001-2003 (n = 82), rates per 1000 deliveries in HIV-infected women rose from 0.0 to 109.8 (P < 0.001) for pre-eclampsia and from 7.7 to 61.0 (P < 0.001) for fetal death. In all pregnant women, factors associated with pre-eclampsia or fetal death were multiple gestation [adjusted odds ratio (OR) 3.6; 95% confidence interval (CI), 2.3-5.6; P < 0.001], HIV infection (adjusted OR, 4.9; 95% CI, 2.4-10.1; P < 0.001), multiparity (adjusted OR, 0.76; 95% CI, 0.58-0.98; P = 0.040) and tobacco smoking (adjusted OR, 0.65; 95% CI, 0.46-0.90; P = 0.010). The use of HAART prior to pregnancy (adjusted OR, 5.6; 95% CI, 1.7-18.1; P = 0.004) and tobacco smoking (adjusted OR, 0.183; 95% CI, 0.054-0.627; P = 0.007) were risk factors in HIV-infected women.

CONCLUSIONS

HIV infection treated with HAART prior to pregnancy was associated with a significantly higher risk for pre-eclampsia and fetal death.

Thrombophilia Is Significantly Associated With Severe Preeclampsia

The role of thrombophilia in the pathogenesis of preeclampsia is controversial. The aim of this case-controlled study was to determine whether thrombophilia increases the risk of preeclampsia or interferes with its clinical course. A total of 808 white patients who developed preeclampsia (cases) and 808 women with previous uneventful pregnancies (controls) matched for age and parity were evaluated for inherited and acquired thrombophilia (factor V Leiden; factor II G20210A; methylenetetrahydrofolate reductase C677T; protein S, protein C, and antithrombin III deficiency; anticardiolipin antibodies; lupus anticoagulant; and hyperhomocysteinemia). Odds ratios (ORs) with 95% confidence intervals (CIs) for risk of being carriers of thrombophilia in cases compared with controls and for risk of maternal life-threatening complications and adverse perinatal outcomes in preeclamptic patients with or without thrombophilia were calculated. Women with severe preeclampsia (406 cases) had a higher risk (OR, 4.9; 95% CI, 3.5 to 6.9) of being carriers of either an inherited or acquired thrombophilic factor, except for protein S, protein C, and antithrombin deficiency. In women with mild preeclampsia (402 cases), only prothrombin and homozygous methylenetetrahydrofolate reductase gene mutations were significantly more prevalent than in the controls. Thrombophilic patients with severe preeclampsia are at increased risk of acute renal failure (OR, 1.8; 95% CI, 1.5 to 2.2), disseminated intravascular coagulation (OR, 2.7; 95% CI, 1.1 to 6.4), abruptio placentae (OR, 2.6; 95% CI, 1.2 to 6.0) and perinatal mortality (OR, 1.7; 95% CI, 1.5 to 2.2) compared with nonthrombophilic preeclamptic patients. Our study demonstrates a significant association between maternal thrombophilia and severe preeclampsia in white women. Thrombophilia also augments the risk of life-threatening maternal complications and adverse perinatal outcomes in preeclamptic patients.

Diagnostic criteria and reporting procedures for pre-eclampsia: A national survey among obstetrical departments in Denmark

OBJECTIVE

A precondition for the rational use of obstetric databases in biomedical research is detailed knowledge on how data are being generated. We identified the diagnostic procedures and criteria for pre-eclampsia (PE) and assessed the level of obstetric training of the personnel responsible for the records submitted to the patient registry at the Danish National Board of Health.

STUDY DESIGN

A structured questionnaire, including three case stories, was sent to the chief consultant of the department.

RESULTS

Thirty-three out of the 34 Danish departments (97%) returned the questionnaire. Reporters of pregnancy diagnoses to the National Patient Registry differed widely in training. For complicated pregnancies, departments ranged from having only specialists reporting all cases to secretaries reporting up to 50%. Cut off limits of blood pressure (BP) and protein loss used to diagnose pre-eclampsia showed large differences across departments. The diagnoses given to three case stories showed little correlation to the criteria the departments reported using.

CONCLUSION

Even in a small country like Denmark with 34 obstetrical departments, there was little consensus on the diagnostic criteria for pre-eclampsia. The findings emphasize the need for standardizing diagnostic criteria and reporting practice and may have implications on how to interpret data regarding pre-eclampsia.

Prediction and prevention of preeclampsia and IUGR

Preeclampsia, being one of the leading causes of maternal and perinatal morbidity and mortality, has been the subject of extensive research since its description. Preeclampsia has been called the disease of theories due to the enigma surrounding its exact pathophysiology. Despite the absence of treatment that reverses the disease process once started, screening for preeclampsia and intrauterine growth restriction (IUGR) has been a major clinical and research issue since the disease was first reported. This review evaluates the current evidence for prediction and prevention of preeclampsia and IUGR using clinical tests, maternal serum markers, and uterine artery Doppler screening. In addition, we critically evaluate the evidence regarding the different therapeutic strategies for the prevention of preeclampsia and IUGR and the latest clinical recommendations for their use.

Use of uterine Doppler in an Australian level II maternity hospital

OBJECTIVE

To evaluate the clinical usefulness of uterine Doppler.

DESIGN

Retrospective study between March 2001 and March 2003.

SETTING

A high-risk population of pregnant women in a busy level II Maternity unit.

METHODS

Resistance index (RI) measurements of the right and left uterine artery were obtained by using pulsed wave Colour Doppler. The presence of a unilateral or bilateral early diastolic notch was noted. An abnormal result was defined as a mean RI >or= 0.58 with no, one or two notches or a mean RI < 0.58 in the presence of bilateral notches.

RESULTS

Pre-eclampsia was found in 45 (24.7%) women, gestational hypertension (GH) in 22 (12.1%) and intrauterine growth restriction (IUGR) in 42 (23.1%) of women included (total 59.9%). In the overall group, 127 (69.8%) women were found to have abnormal uterine artery Doppler results and 55 (30.2%) of patients had a normal Doppler study. No significant differences were found between the group of women with abnormal uterine artery Doppler and the women with a normal velocity waveform in the prediction of pre-eclampsia, IUGR and GH, this was also true in the various high-risk-subgroups.

CONCLUSIONS

Uterine Doppler is not particularly useful to the obstetrician in the management of patients with an a priori very high risk to develop uteroplacental insufficiency.

Hypertension in pregnancy

Hypertension in pregnancy contributes significantly to both maternal and neonatal morbidity and mortality. Among different forms of pregnancy-associated hypertension, preeclampsia-eclampsia has the highest impact on morbidity and mortality. Chronic hypertension may result in preterm and small for gestational age infants, even when it is mild-to-moderate. Chronic hypertension is a risk factor for superimposed preeclampsia and results in higher rates of adverse outcome. Preeclampsia is a multisystemic disease that is thought to be initiated by abnormalities in placental perfusion and endothelial dysfunction, ultimately resulting in multiorgan failure. Preeclampsia is more common in women of minority ethnicity who are socioeconomically disadvantaged. Pharmacologic therapy for hypertensive disorders in pregnancy is limited by concerns regarding the safety of both mother and fetus. Although treatment of severe hypertension is not debated, there is no consensus on the rationale for pharmacologic therapy of mild-to-moderate hypertension in pregnancy.

Stiffness of the arterial wall, joints and skin in women with a history of pre-eclampsia

OBJECTIVE

The epidemiology of pre-eclampsia suggests a constitutional component for the disorder. We have recently shown an association for blood pressure (BP) with stiffness of joints and skin in adolescents, suggesting that constitutionally determined stiffness of body tissues is associated with blood pressure. Therefore, we compared stiffness of the arterial wall, joints and skin between women with a history of pre-eclampsia and women with an uncomplicated pregnancy.

DESIGN

Cases were 44 women with a history of early onset pre-eclampsia and controls were 46 women with a history of uncomplicated pregnancy. Arterial stiffness was determined non-invasively with pulse wave velocity measurement. As a measure of capsule and ligament stiffness, the active range of motion of various joints was measured. Skin stiffness was measured using a tissue compliance meter. Analysis of variance (ANOVA) multiple comparison tests were used for comparison of the study groups. Linear regression models were used to determine the associations between stiffness parameters and possible confounders.

RESULTS

For the cases, body mass index (BMI) was significantly higher and age and parity were significantly lower. BP was significantly higher for the cases. Stiffness of the arterial wall, joints and skin were significantly higher. After adjustment for mean arterial pressure, stiffness of the joints and skin were significantly higher, but no difference remained for arterial stiffness.

CONCLUSIONS

Women with a history of pre-eclampsia had a significantly higher stiffness of the arterial wall, joints and skin compared with controls. This suggests a constitutionally determined stiffness of connective tissues in former pre-eclamptic cases.

Pre-eclampsia

Pre-eclampsia is a major cause of maternal mortality (15-20% in developed countries) and morbidities (acute and long-term), perinatal deaths, preterm birth, and intrauterine growth restriction. Key findings support a causal or pathogenetic model of superficial placentation driven by immune maladaptation, with subsequently reduced concentrations of angiogenic growth factors and increased placental debris in the maternal circulation resulting in a (mainly hypertensive) maternal inflammatory response. The final phenotype, maternal pre-eclamptic syndrome, is further modulated by pre-existing maternal cardiovascular or metabolic fitness. Currently, women at risk are identified on the basis of epidemiological and clinical risk factors, but the diagnostic criteria of pre-eclampsia remain unclear, with no known biomarkers. Treatment is still prenatal care, timely diagnosis, proper management, and timely delivery. Many interventions to lengthen pregnancy (eg, treatment for mild hypertension, plasma-volume expansion, and corticosteroid use) have a poor evidence base. We review findings on the diagnosis, risk factors, and pathogenesis of pre-eclampsia and the present status of its prediction, prevention, and management.

Factor II

OBJECTIVE

To evaluate whether the determination of maternal plasma Factor II:C (FII:C) and mean uterine artery resistance index may be useful to early predict pre-eclampsia in patients with gestational hypertension.

DESIGN

Prospective study.

SETTING

Consecutive enrollment in a public tertiary clinical care centre.

PATIENTS

A total of 65 women with gestational hypertension at 24-26 weeks.

INTERVENTION

Measurements of maternal plasma FII:C activity levels, ultrasonographic biometrical parameters and Doppler velocimetry of maternal uterine arteries.

MAIN OUTCOME MEASURE(S)

The probability of developing pre-eclampsia was the main outcome of the study and it was computed by combining the FII:C and the mean uterine artery resistance index cut-off points, chosen by receiver operating characteristic (ROC) curve analysis.

RESULTS

F-II:C activity levels and mean uterine artery resistance index were significantly (both P < 0.01) higher in women who developed pre-eclampsia. A weak, but significant correlation (r = 0.3, P < 0.05) was found between these two parameters. FII:C activity levels at the cut-off value of 136.5% achieved a sensitivity of 61.1% and a specificity of 71.3%, while mean uterine artery resistance index (RI) at the cut-off value of 0.57 showed a sensitivity of 85.7% and a specificity of 90.2% in predicting the onset of pre-eclampsia. When both FII:C and mean uterine RI were over the cut-off points the positive predictive value was of 89%, with a 100% negative predictive value when both were below the cut-off points.

CONCLUSION

F-II:C activity levels and mean uterine artery resistance index determination at mid trimester may improve the prediction of superimposed pre-eclampsia on women with early onset gestational hypertension.

Strategies to prevent eclampsia in a developing country: I. Reorganization of maternity services

OBJECTIVE

To determine whether changes in primary and secondary care service delivery could prevent antenatal eclampsia.

METHOD

One intervention (St. Catherine) and two control (St. Ann, Manchester) parishes were chosen. The health system in St. Catherine was restructured. Primary antenatal clinics had clear instructions for referring patients to a high-risk antenatal clinic or to hospital. Guidelines were provided to high-risk clinics and the antenatal ward for appropriate treatment of hypertension and preeclampsia when induction of labor should occur. Antenatal eclampsia incidence was monitored before and during the intervention and compared with control parishes (no intervention). Each eclampsia case was investigated to identify inadequacies in the system.

RESULTS

The process resulted in better identification of women at risk. Antenatal eclampsia incidence dropped dramatically as care improved. Compared with control areas, by completion of the study, the rate was significantly lower than at the start: OR 0.19 (95% CI: 0.13-0.27; p<0.001 trend). Antenatal admissions for hypertensive disorders declined significantly, and the number of bed days halved.

CONCLUSION

Reorganization of maternal care can have major public health benefits and cost savings; however, women need to be alerted to recognise and act upon signs of impending eclampsia.

A survey of Canadian practitioners regarding the management of the hypertensive disorders of pregnancy

BACKGROUND

How Canadian practitioners are managing the hypertensive disorders of pregnancy (HDP) is not known, particularly in relation to the 1997 guidelines published by the Canadian Hypertension Society (CHS).

METHODS

A survey, with French and English versions (and covering diagnosis, evaluation, and management of pregnancy hypertension), was mailed to all members of the Society of Obstetricians and Gynaecologists of Canada (SOGC) (N = 1757, including obstetricians, family doctors practicing obstetrics, and midwives). Additionally, internists [i.e., all nephrologists (N = 191) and a random sample of 25% of general internists (N = 450)] registered with the Royal College of Physicians and Surgeons of Canada were sampled. The survey was distributed in two mailings and one reminder card. Data were entered into Microsoft Access, and Graph Pad Prism used to summarize responses [N (%)]. Differences in practice between specialties were examined, with a Bonferroni correction used to calculate a significant p value based on the number of comparisons and alpha of 0.05.

RESULTS

Respondents numbered 1187 (49.5%), with 466 not informative for the purpose of the study (due to retirement, or practices that do not include pregnant women with hypertension). The final analysis included 721 completed surveys. For all types of HDP, most internists, family doctors, and midwives initiate nonpharmacological therapy (most common advice to quit work) at dBP 80-89 mmHg (i.e., primary prevention). Only for preeclampsia do obstetricians most frequently use this threshold; otherwise, dBP 90-99 mmHg is usually chosen. For nonsevere hypertension, antihypertensive drug therapy (most commonly methyldopa or labetalol) is started by most practitioners at dBP 90-99 mmHg, although obstetricians are more likely to choose a higher threshold (p < 0.0001). There is little agreement about dBP treatment goal; most internists and family doctors normalize dBP, whereas obstetricians appear to be divided on dBP goals of 80-89 (46-51%) vs. 90-99 mmHg (41-44%) for all HDP (p = 0.66). Severe hypertension is commonly treated with parenteral hydralazine, labetalol, or magnesium sulphate. Short-acting or sustained release nifedipine is used rarely/never by most practitioners. Approximately one-third of obstetricians and family doctors use diazepam to treat eclampsia. The vast majority use MgSO4 prophylactically in women with preeclampsia.

INTERPRETATION

This survey has clarified current stated management of women with HDP, and identified the need for both research into the dBP treatment goal that optimizes pregnancy outcomes among women with HDP, and translation of definitive studies into clinical practice.

Vasoconstriction caused by cocaine is enhanced by sodium salicylate: is inducible nitric oxide synthase mRNA related?

We have previously found that sodium salicylate (NaSal), injected into chicken eggs at nontoxic doses used for quantifying hydroxyl free radicals in hearts and brains of embryos, caused or exacerbated hemorrhages and dramatically reduced hatchability when combined with cocaine (Coc). It has also been reported that inducible nitric oxide synthase (iNOS) gene expression is altered in brain in response to vascular damage and inflammation. In this study we measured diameters of membrane-bound blood vessels (BV) before and after pretreatment with saline (NaCl) or NaSal (100 mg/kg egg), followed by infusion of either NaCl or Coc HCl (total of 67.5 mg/kg egg) during 15 min. Brains and hearts of the embryos were then analyzed for iNOS messenger RNA (mRNA) concentrations. Coc caused vasoconstriction that was significant 5 min postinfusion (5 min PI) of the entire dose (ie after 67.5 mg/kg egg). Significant vasoconstriction was evident within 5 min in the group injected with NaSal followed by infusion with Coc (ie after 22.5 mg Coc/kg egg). Expression of iNOS mRNA was significantly increased only in the brains of the group exposed to NaSal plus Coc, and the increase was inversely related to BV diameter. These data are discussed in relation to effects of salicylate upon prostanoid synthesis and/or nitric oxide synthesis via iNOS inhibition and their possible relationship to Coc-associated cerebral vascular and/or cardiovascular events in abusing humans.

Is pre-eclampsia more than one disease?

OBJECTIVES

The clinical characteristics of pre-eclampsia (gestational hypertension and proteinuria) may represent separate pathogenetic conditions. Pre-eclampsia accompanied by restricted fetal growth may originate from abnormal implantation, and appropriate or high birthweights may indicate a mixture of conditions, ranging from mild pre-eclampsia with modest placental involvement to hypertensive conditions without placental disease.

DESIGN

Prospective, observational study.

SETTING

General population.

POPULATION

We used data from the Medical Birth Registry of Norway, a population-based registry that has recorded births since 1967. For this study, we used information on length of gestation and presence of pre-eclampsia among 1,679,205 singletons born between 1967 and 1998. Pre-eclampsia was diagnosed in 44,220 (2.6%) pregnancies.

METHODS

We studied the risk of pre-eclampsia in relation to standardised measures (z scores) of birthweight, adjusted for length of gestation, and stratified by term and preterm delivery. We also explored whether gestational diabetes was more prevalent in conjunction with preterm than term pre-eclampsia.

MAIN OUTCOME MEASURES

Pre-eclampsia diagnosed at term or preterm.

RESULTS

For pre-eclampsia diagnosed around term, there was a U-shaped association with birthweight. Compared with appropriate birthweights for gestation, the risk of term pre-eclampsia was more than fourfold higher (relative risk [RR] 4.5, 95% confidence interval [CI], 4.3 to 4.7) if the baby's birthweight was lower than two standard deviations under the mean. For birthweights three standard deviations or higher than the mean, pre-eclampsia was more than twice as likely (RR 2.6, 95% CI 2.2-2.9). In contrast, the risk of preterm pre-eclampsia displayed an L-shaped association with birthweight. Low birthweight (less than -2 standard deviations) was associated with greatly increased risk (RR 9.9, 95% CI 9.1-10.9), but for high birthweights (>or=3 standard deviations), there was no association with the risk of preterm pre-eclampsia (RR 1.2, 95% CI 0.7-2.1). The prevalence of gestational diabetes was three times (prevalence ratio 3.3, 95% CI 2.6-3.6) higher in preterm than term pre-eclampsia.

CONCLUSION

Whereas pre-eclampsia with preterm delivery associated with low birthweight may be caused by underlying placental abnormality, pre-eclampsia delivered at term may represent a mixture of conditions, ranging from mild pre-eclampsia with moderate placental affection to hypertensive conditions in pregnancy without placental dysfunction.

Hypertensive Disorders of Pregnancy

Hypertensive disorders occur in 6% to 8% of all pregnancies, are the second leading cause of maternal death, and contribute to significant neonatal morbidity and mortality. This is a problem not only in inpatient settings, as ambulatory and home-care nurses are increasingly being called upon to monitor women who are at high risk and may have hypertensive disorders. To prevent hypertension-induced problems in pregnant women, nurses must have strong assessment, advocacy, and counseling skills. Nurses also must provide care based on the latest national standards as described in this article.

Social deprivation and poor access to care as risk factors for severe pre-eclampsia

OBJECTIVE

To estimate the associations between biomedical, social and health care factors and the occurrence of severe pre-eclampsia, eclampsia or HELLP syndrome.

STUDY DESIGN

A case-control study conducted in 14 of the 15 maternity hospitals of Brussels. Cases were all 99 women who delivered in these hospitals in 1996 and who had severe pre-eclampsia, eclampsia or HELLP syndrome. Controls were 200 women without these severe maternal conditions, randomly selected among women who delivered in the same hospitals during the same period. Crude odds ratios were computed and adjusted odds ratios were derived from logistic regression.

RESULTS

Indicators of social deprivation such as low educational level, poverty and illegal residence or asylum request, were strongly associated with the outcome in univariate analysis. So were African or Turkish ethnicity, obesity, chronic hypertension and primiparity. Logistic regression showed that no access to national health insurance and history of residence in another country were strongly and independently associated with the outcome (adjusted odds ratio = 4.0 (95% confidence interval 1.1, 14.0) and 3.7 (95% confidence interval 1.9, 7.3), respectively).

CONCLUSIONS

The burden of pre-eclampsia is concentrated in socially disadvantaged women. Health services should be more responsive to the specific needs of these women. Low access to health care may contribute to the occurrence of severe pre-eclampsia in our setting.

Randomized controlled trial using low-dose aspirin in the prevention of pre-eclampsia in women with abnormal uterine artery Doppler at 23 weeks' gestation

OBJECTIVE

Pre-eclampsia, which is a major cause of perinatal and maternal morbidity and mortality, is thought to be due to impaired perfusion of the placenta. There is contradictory evidence that the administration of low-dose aspirin may provide effective prophylaxis against the subsequent development of pre-eclampsia. In this study we tested the hypothesis that in women identified as being at high-risk for pre-eclampsia, because of impaired flow in the uterine arteries, the prophylactic use of low-dose aspirin from 23 weeks of gestation can reduce the incidence of pre-eclampsia.

METHODS

We used color and pulsed Doppler to measure the flow in the uterine arteries in 19,950 singleton pregnancies at 22-24 weeks of gestation. Those women exhibiting increased impedance were recruited into a randomized study of aspirin 150 mg per day or placebo. We compared the two groups for the incidence of pre-eclampsia and the other consequences of impaired placentation.

RESULTS

The screening study identified 844 women (4.2%) as being at high risk of uteroplacental insufficiency. After exclusion and refusal, 560 women were randomly allocated to aspirin 150 mg or placebo per day until 36 weeks' gestation. There were no significant differences between the aspirin and placebo groups in either the incidence of pre-eclampsia (18% vs. 19%, P = 0.6) or pre-eclampsia requiring delivery below 34 weeks (6% vs. 8%, P = 0.36). Furthermore, the administration of aspirin did not significantly alter the incidence of preterm delivery (24% vs. 27%, P = 0.46), birth weight below the 5th centile (22% vs. 24%, P = 0.4), perinatal death (3% vs. 1%, P = 0.33) or placental abruption (4% vs. 2%, P = 0.12).

CONCLUSION

In pregnancies with impaired placentation, as demonstrated by increased impedance to flow in the uterine arteries, the daily administration of 150 mg aspirin after 23 weeks of gestation does not prevent the subsequent development of pre-eclampsia.

Factors regulating trophoblast migration and invasiveness: possible derangements contributing to pre-eclampsia and fetal injury

Impaired trophoblast invasiveness and spiral arterial remodelling, which results in poor placental perfusion during early pregnancy, is believed to cause fetal injury and growth retardation, and also endothelial cell activation/dysfunction in a susceptible mother, leading to clinical manifestations of pre-eclampsia. This article briefly reviews the regulatory roles of certain locally active factors in trophoblast migration and invasiveness. This background is then used to discuss and debate whether derangements or dysfunction of some of these factors can manifest as early serum markers predictive of the disease, as opposed to the intermediate and late stage markers which may reflect manifestations and consequences of the disease. Of particular significance are the observed derangements in uPA/uPAR/PAI system, IGFBP-1, HGF, HB-EGF and TGFbeta, factors which are known to regulate trophoblast migration and invasiveness in situ. An emphasis is placed on the need for longitudinal studies in order to identify predictive serum markers which may help strategies for prevention or amelioration of fetal injury and pre-eclampsia.

Pre-eclampsia and thrombophilia

Pre-eclampsia is a major cause of perinatal and maternal morbidity and mortality worldwide. Although knowledge of the precise aetiology remains uncertain a number of risk factors have been described. Thrombophilias have been associated with pre-eclampsia in a number of studies and it is biologically plausible that they may contribute to the uteroplacental thrombosis that is frequently seen in pre-eclampsia. If this association is confirmed, there is the potential to investigate preventive treatments, including low-molecular-weight heparins, aspirin and folate.

Low-dose aspirin in pregnancy: maternal and neonatal aspirin concentrations and neonatal prostanoid formation

OBJECTIVE

To evaluate maternal and neonatal plasma concentrations of acetylsalicylic acid and salicylic acid and the neonatal endogenous prostanoid formation during low-dose aspirin prophylaxis (LDA; 100 mg daily) in pregnant women.

METHODS

Concentrations of acetylsalicylic acid and salicylic acid in maternal plasma after at least 4 weeks of LDA (n = 14) and in umbilical cord plasma of newborns after maternal LDA (n = 7) were determined by gas chromatography-mass spectrometry. Platelet and renal formation of thromboxane A2 and the formation of prostaglandin E2 and prostacyclin were evaluated in vivo by quantification of index metabolites in plasma and urine by gas chromatography-mass spectrometry in neonates after maternal LDA (n = 14) and in a control group.

RESULTS

In the pregnant women, acetylsalicylic acid and salicylic acid concentrations rapidly increased after ingestion of LDA. Acetylsalicylic acid was completely eliminated within 4 hours, whereas salicylic acid was detected with low concentrations at 18 and 21 hours after dosing. In the neonates, acetylsalicylic acid was not detected. Salicylic acid was detected in 1 infant only. Platelet thromboxane A2 formation in the newborn infants was significantly suppressed but recovered within 2 to 3 days after discontinuation of LDA. Renal thromboxane A2 formation and the formation of prostaglandin E2 and prostacyclin were not affected by LDA.

CONCLUSION

In pregnant women who are treated with LDA, acetylsalicylic acid is not completely inactivated in the portal circulation but reaches the uteroplacental circulation and exerts antiplatelet effects in the fetus and newborn.

Fall in mean arterial pressure and fetal growth restriction in pregnancy hypertension: an updated metaregression analysis

OBJECTIVE

To update our previous analysis of randomized controlled trials in pregnancy hypertension, which discerned that greater treatment-induced decreases in maternal mean arterial pressure (MAP) appear to adversely affect fetal growth.

METHODS

We conducted an English-language computer search of MEDLINE, Hypertension in Pregnancy, the relevant Cochrane reviews, and the bibliographies of retrieved papers, review articles, and standard obstetric and toxicology texts. Metaregression analysis was used to compare the change in MAP from enrollment to delivery with birth weight.

RESULTS

Seven new trials with 335 women were added to the 27 trials with 2305 women previously reported. No new trials reported on the frequency of small for gestational age infants. Treatment-induced mean difference in MAP was associated with lower mean birth weight (slope: -17.55 [SD 6.67], r2 = 0.19, Spearman's non-parametric p = 0.031, Pearson's parametric p = 0.013). Therefore, over the range of reported mean differences in MAP, a 10 mm Hg fall in MAP was associated with a 176 g decrease in birth weight, and 19% of the birth weight difference between trials could be explained by differential blood pressure control.

CONCLUSION

These results strengthen the association between blood pressure control and restricted fetal growth, and reinforce the need for new data to elucidate optimal antihypertensive use for mild to moderate pregnancy hypertension.

Searching for preeclampsia genes: the current position

Although there is substantial evidence that preeclampsia has a genetic background, the complexity of the processes involved and the fact that preeclampsia is a maternal-fetal phenomenon does not make the search for the molecular basis of preeclampsia genes easy. It is possible that the single phenotype 'preeclampsia' in fact should be divided into different sub-groups on genetic or biochemical level. In the present review, the preeclampsia phenotype and its pathophysiologic features are discussed. Family studies and postulated inheritance models are summarized. A systematic overview is given on the numerous candidate gene studies and gene-expression studies performed so far and on the currently available genome-wide scan data. Despite extensive research the molecular genetic basis of preeclampsia remains unclear. Future studies will hopefully enhance our insights in the molecular pathogenesis of preeclampsia.

Position of the American Dietetic Association: nutrition and lifestyle for a healthy pregnancy outcome

It is the position of the American Dietetic Association that women of childbearing potential should maintain good nutritional status through a lifestyle that optimizes maternal health and reduces the risk of birth defects, suboptimal fetal growth and development, and chronic health problems in their children. The key components of a health-promoting lifestyle during pregnancy include appropriate weight gain; consumption of a variety of foods in accordance with the Food Guide Pyramid; appropriate and timely vitamin and mineral supplementation; avoidance of alcohol, tobacco, and other harmful substances; and safe food-handling. Prenatal weight gain within the Institute of Medicine (IOM) recommended ranges is associated with better pregnancy outcomes. The total energy needs during pregnancy range between 2,500 to 2,700 kcal a day for most women, but prepregnancy body mass index, rate of weight gain, maternal age, and physiological appetite must be considered in tailoring this recommendation to the individual. The consumption of more food to meet energy needs and the increased absorption and efficiency of nutrient utilization that occurs in pregnancy are generally adequate to meet the needs for most nutrients. However, vitamin and mineral supplementation is appropriate for some nutrients and situations. This statement also includes recommendations pertaining to use of alcohol, tobacco, caffeine, street drugs, and other substances during pregnancy; food safety; and management of common complaints during pregnancy and specific health problems. In particular for medical nutrition therapy, pregnant women with inappropriate weight gain, hyperemesis, poor dietary patterns, phenylketonuria (PKU), certain chronic health problems, or a history of substance abuse should be referred to a qualified dietetics professional.

An exploratory study of fetal behavior at 33 and 36 weeks gestational age in hypertensive women

The relationship between maternal blood pressure (BP) and fetal behaviors as well as differential spontaneous and vibroacoustic elicited fetal behaviors were examined in hypertensive (n = 21) compared to normotensive (n = 22) women at 33 and 36 weeks gestational age (GA). Maternal BP was negatively related to GA at birth and birth weight. On average, fetuses of hypertensive women were born 2 weeks earlier (38 weeks GA) and 340 g lighter. Maternal systolic BP was negatively related to the number of spontaneous body movements observed on ultrasound scan over 20 min and the magnitude of the fetal heart rate (FHR) acceleration elicited by a vibroacoustic stimulus. At 36 weeks GA, vibroacoustic stimulation elicited differential responding with fetuses in the hypertensive compared to the normotensive group having fewer body movements, a lower magnitude of FHR acceleration, and a lack of cardiac-body movement coupled responses. These findings suggest a relationship between maternal BP and fetal behaviors and differential functional development of sensory-motor response systems which need to be characterized in the subgroups of hypertensive disorders observed during pregnancy.

DNA methylation and breast carcinogenesis

Knowledge about breast carcinogenesis has accumulated during the last decades but has barely been translated into strategies for early detection or prevention of this common disease. Changes in DNA methylation have been recognized as one of the most common molecular alterations in human neoplasia and hypermethylation of gene-promoter regions is being revealed as one of the most frequent mechanisms of loss of gene function. The heritability of methylation states and the secondary nature of the decision to attract or exclude methylation support the idea that DNA methylation is adapted for a specific cellular memory. According to Hanahan and Weinberg, there are six novel capabilities a cell has to acquire to become a cancer cell: limitless replicative potential, self-sufficiency in growth signals, insensitivity to growth-inhibitory signals, evasion of programmed cell death, sustained angiogenesis and tissue invasion and metastasis. This review highlights how DNA-methylation contributes to these features and offers suggestions about how these changes could be prevented, reverted or used as a 'tag' for early detection of breast cancer or, preferably, for detection of premalignant changes.

Activated protein C in normal human pregnancy and pregnancies complicated by severe preeclampsia: a therapeutic opportunity?

OBJECTIVES

Given the efficacy and safety of recombinant human activated protein C (rhAPC) in the systemic inflammatory response syndrome, this study was designed to review the evidence for a role for APC in the pathogenesis of preeclampsia. Preeclampsia is a proinflammatory and procoagulant state, and it is a pregnancy-specific condition that mimics the systemic inflammatory response syndrome. rhAPC reduces mortality in patients with systemic inflammatory response syndrome and could potentially have a role as disease-modifying therapy in preeclampsia. To determine which patients would be offered rhAPC, the literature pertaining to fetal/neonatal outcomes for preeclampsia remote from term, transplacental transport of protein C, and pregnancy experience with the compound were reviewed.

DATA SOURCES

MEDLINE, review papers, hand searches of relevant nonindexed journals, and the bibliographies of relevant textbooks and articles reviewed.

STUDY SELECTION

Randomized controlled trials were considered to provide the best quality of clinical data. Case-control series were considered over uncontrolled data. Some data were not available in the published literature (e.g., neonatal outcomes at various gestational ages and birthweights after a hypertensive pregnancy; and transplacental transfer of protein C), and these data were determined by us.

DATA EXTRACTION

Data were extracted by systematic review onto data collection sheets. Because of the quality of the data, this review is primarily qualitative.

DATA SYNTHESIS

APC levels fall during normal gestation, returning to normal values by 6 wks postpartum. Limited data suggest that early onset preeclampsia is a state of further, and inappropriate, reduction in APC. Preeclampsia resembles systemic inflammatory response syndrome in this regard. After hypertensive pregnancies, neonates have a 50% chance of intact survival if delivered after 27 + 0 wks of gestation with a birthweight of >600 g. It would seem ethical to offer women with preeclampsia with <50% chance of intact perinatal survival novel and potentially disease-modifying therapy such as rhAPC, especially as there is no transplacental transfer of protein C. Limited evidence would support the use of rhAPC in women with severe postpartum preeclampsia.

CONCLUSIONS

Sufficient data exist to support the use of rhAPC in phase II clinical studies for women with either early onset preeclampsia or severe or deteriorating postpartum disease.

Hypertensive diseases and eclampsia

Worldwide, pre-eclampsia and eclampsia contribute to the death of a pregnant woman every 3 min. In the UK in recent decades, hypertensive disorders of pregnancy have remained one of the leading causes of both maternal and perinatal morbidity and mortality. The management of pregnancies complicated by hypertension has not significantly altered for many years, possibly as a result of little progress being made in our understanding of the condition. New insights, however, have recently been gained into the pathophysiology of pre-eclampsia. These have yet to be translated into new interventions or to make any impact on clinical management of these pregnancies. This review will therefore focus on recent advances relating to research into the aetiology and pathogenesis of pre-eclampsia, but will conclude with a brief update on current therapeutic strategies.

The interval between pregnancies and the risk of preeclampsia

BACKGROUND

The risk of preeclampsia is generally lower in second pregnancies than in first pregnancies, but not if the mother has a new partner for the second pregnancy. One explanation is that the risk is reduced with repeated maternal exposure and adaptation to specific antigens from the same partner. However, the difference in risk might instead be explained by the interval between births. A longer interbirth interval may be associated with both a change of partner and a higher risk of preeclampsia.

METHODS

We used data from the Medical Birth Registry of Norway, a population-based registry that includes births that occurred between 1967 and 1998. We studied 551,478 women who had two or more singleton deliveries and 209,423 women who had three or more singleton deliveries.

RESULTS

Preeclampsia occurred during 3.9 percent of first pregnancies, 1.7 percent of second pregnancies, and 1.8 percent of third pregnancies when the woman had the same partner. The risk in a second or third pregnancy was directly related to the time that had elapsed since the preceding delivery, and when the interbirth interval was 10 years or more, the risk approximated that among nulliparous women. After adjustment for the presence or absence of a change of partner, maternal age, and year of delivery, the odds ratio for preeclampsia for each one-year increase in the interbirth interval was 1.12 (95 percent confidence interval, 1.11 to 1.13). In unadjusted analyses, a pregnancy involving a new partner was associated with higher risk of preeclampsia, but after adjustment for the interbirth interval, the risk of preeclampsia was reduced (odds ratio for preeclampsia with a change of partner, 0.73; 95 percent confidence interval, 0.66 to 0.81).

CONCLUSIONS

The protective effect of previous pregnancy against preeclampsia is transient. After adjustment for the interval between births, a change of partner is not associated with an increased risk of preeclampsia.

Untoward effects of rapid-acting antihypertensive agents

Cerebral haemorrhage remains a major cause of hypertensive cerebral mortality. Lowering of raised blood pressure is therefore crucial in the clinical management of hypertensive disorders of pregnancy. This article reviews rapid-acting agents employed in life-threatening situations.