Measurements of blood pressure, oedema and proteinuria in a pregnant population of New Zealand

Blood pressure patterns of hypertensive disorders of pregnancy in first and second trimester and contributing factors: a retrospective study

We aimed to investigate the blood pressure (BP) patterns of hypertensive disorders of pregnancy (HDP) in the first and second trimesters and its contributing factors, which may help us understand its pathogenesis and identify this group of diseases in a timely manner. SPSS 21.0 was used to describe the BP patterns of 688 HDP as well as 2050 normotensive pregnancies respectively before 28 gestational weeks, and the repeated measurements and two-way ANOVA was used to decide the significant difference of blood pressure in the same period. The results revealed blood pressure in HDP underwent a mid-pregnancy drop as normal while the drop was unremarkable in advanced-age or obesity pregnancies. Besides, we found blood pressure was significantly higher in patients during first and second trimesters, not just after 20 weeks. In conclusion, our study indicated a significant elevation of blood pressure had appeared before 20 weeks in HDP pregnancies, we should pay more attention to monitoring blood pressure before 20 weeks, especially for advanced age and obese women.IMPACT STATEMENTWhat is already known on this subject? Gestational hypertension, preeclampsia as well as eclampsia were supposed to have the similar pathogenesis and their time of onset was strictly defined after 20 gestational weeks, while the reason for the time point was not clear. On the other hand, higher blood pressure in the first trimester was associated with increasing risk of developing HDP, while the blood pressure(BP) pattern of normal as well as HDP pregnancy was still controversial, especially for the existence of mid-trimester drop.What do the results of this study add? Firstly, we found blood pressure in HDP underwent a mid-pregnancy drop as normal while the BP drop was unremarkable in advanced-age or obesity pregnancies. Secondly, we noticed the blood pressure in HDP was significantly higher than the normal before 20 weeks, which had not been proved before.What are the implications of these findings for clinical practice and/or further research? On one hand, both the abnormal elevation of BP and the development of the placenta happened in the first trimester suggested toxic substances caused by the defective placenta played a vital role in the onset and aggravation of HDP, which guides us to pay more attention to monitor blood pressure before 20 weeks, especially for advanced age and obesity pregnancies. On the other hand, our results about BP patterns in HDP help us identify this group of diseases in time which can contribute to a better outcome.

American College of Cardiology and American Heart Association blood pressure categories-a systematic review of the relationship with adverse pregnancy outcomes in the first half of pregnancy

OBJECTIVE

A relationship between the 2017 American College of Cardiology and American Heart Association blood pressure thresholds and adverse pregnancy outcomes has been reported, but few studies have explored the diagnostic test properties of these cutoffs.

DATA SOURCES

We systematically searched electronic databases (from 2017 to 2021) for reports of blood pressure measurements in pregnancy, classified according to 2017 American College of Cardiology and American Heart Association criteria, and their relationship with pregnancy outcomes.

STUDY ELIGIBILITY CRITERIA

Studies recording blood pressure at <20 weeks gestation were included.

METHODS

Meta-analyses were used to investigate the strength of the association between blood pressure cutoffs and adverse outcomes, and the diagnostic test properties were calculated.

RESULTS

Of 23 studies included, there was a stepwise relationship between the American College of Cardiology and American Heart Association blood pressure category (when compared with normal blood pressure of <120/80 mmHg) and the strength of the association with preeclampsia. The category of elevated blood pressure had a risk ratio of 2.0 (95% prediction interval, 0.8-4.8), the stage 1 hypertension category had a risk ratio of 3.0 (95% prediction interval, 1.1-8.5), and the stage 2 hypertension category had a risk ratio of 7.9 (95% prediction interval, 1.8-35.1). Between-study variability was related to the magnitude of the association with stronger relationships in larger studies at low risk of bias and with unselected populations with multiple routine blood pressure measurements. None of the systolic blood pressure measurements of <120 mmHg, <130/80 mmHg, or <140/90 mmHg were useful to rule out the development of preeclampsia (all negative likelihood ratios >0.2). Only a blood pressure measurement of ≥140/90 mmHg was a good predictor for the development of preeclampsia (positive likelihood ratio, 5.95). The findings were similar for other outcomes.

CONCLUSION

Although a blood pressure of 120 to 140 over 80 to 90 mmHg at <20 weeks gestation is associated with a heightened risk for preeclampsia and adverse pregnancy outcomes and may assist in risk prediction in multivariable modelling, lowering the diagnostic threshold for chronic hypertension would not assist clinicians in identifying women at heightened risk.

Pregnancy Outcomes and Blood Pressure Visit-to-Visit Variability and Level in Three Less-Developed Countries

[Figure: see text].

Are blood pressure level and variability related to pregnancy outcome? Analysis of control of hypertension in pregnancy study data

OBJECTIVE

To examine the relationship between pregnancy outcomes and BP level and variability.

DESIGN

Secondary analysis of CHIPS trial data (Control of Hypertension In Pregnancy Study, NCT01192412).

SETTING

International.

POPULATION OR SAMPLE

Women with chronic or gestational hypertension.

METHODS

BP measurement was standardised in outpatient clinics. Adjusted (including for allocated group) mixed effects logistic regression was used to assess relationships between major CHIPS outcomes and both BP level (mean of clinic readings) and visit-to-visit within-participant BP variability (standard deviation and average real variability of absolute successive difference of BP values). BP values 7-28 days prior to outcomes (or birth for perinatal outcomes) were excluded in sensitivity analyses.

MAIN OUTCOME MEASURES

Major CHIPS outcomes.

RESULTS

Among 961 (97.4%) women, higher BP level was associated with more adverse maternal and perinatal outcomes (usually at p < 0.001) except for serious maternal complications. Among 913 (92.5%) women with at least two post-randomisation outpatient visits, higher BP variability was associated with increased odds of severe hypertension and pre-eclampsia (usually at p < 0.01). Sensitivity analyses suggested reverse causality for these maternal outcomes, but greater diastolic BP variability may have been associated with fewer adverse perinatal outcomes.

CONCLUSIONS

Higher BP is an adverse prognostic marker, regardless of target BP. While the association between higher BP variability and severe hypertension and pre-eclampsia may be related to higher BP at diagnosis, our results suggest a possible advantage of BP variability for the fetus, through undefined mechanisms.

TWEETABLE ABSTRACT

Higher blood pressure (BP) is associated with more adverse pregnancy outcomes, but higher BP variability may be good for the baby.

Paternal Determinants in Preeclampsia

Preeclampsia is a condition associated with high rates of maternal-fetal morbidity and mortality. It usually occurs in 3–10% of nulliparous women and 18% of previously affected women. Different lines of evidence have demonstrated the role of the father in the onset of preeclampsia. The placenta is the cornerstone of preeclampsia and poses important paternal genetic determinants; in fact, the existence of a “paternal antigen” has been proposed. Nulliparity is a well-known risk factor. Change of partner to a woman without history of preeclampsia increases the risk; however, this change decreases in women with history of the condition. High interval between pregnancies, short sexual intercourse before pregnancy, and conception by intracytoplasmic sperm injection suggest a limited exposure to the so-called paternal antigen. A man who was born from a mother with preeclampsia also increases the risk to his partner. Not only maternal but also paternal obesity is a risk factor for preeclampsia. Fetal HLA-G variants from the father increased the immune incompatibility with the mother and are also significantly associated with preeclampsia in multigravida pregnancies. An analysis of a group of Swedish pregnant women showed that the risk for preeclampsia is attributable to paternal factors in 13% of cases, which could be related to genetic interactions with maternal genetic factors. This review aimed to evaluate the evidences of the father’s contribution to the onset of preeclampsia and determine the importance of including them in future studies.

Obesity and Preeclampsia: Common Pathophysiological Mechanisms

Preeclampsia is a disorder specific of the human being that appears after 20 weeks of pregnancy, characterized by new onset of hypertension and proteinuria. Abnormal placentation and reduced placental perfusion associated to impaired trophoblast invasion and alteration in the compliance of uterine spiral arteries are the early pathological findings that are present before the clinical manifestations of preeclampsia. Later on, the endothelial and vascular dysfunction responsible of the characteristic vasoconstriction of preeclampsia appear. Different nutritional risk factors such as a maternal deficit in the intake of calcium, protein, vitamins and essential fatty acids, have been shown to play a role in the genesis of preeclampsia, but also an excess of weight gain during pregnancy or a pre-pregnancy state of obesity and overweight, which are associated to hyperinsulinism, insulin resistance and maternal systemic inflammation, are proposed as one of the mechanism that conduce to endothelial dysfunction, hypertension, proteinuria, thrombotic responses, multi-organ damage, and high maternal mortality and morbidity. Moreover, it has been demonstrated that pregnant women that suffer preeclampsia will have an increased risk of future cardiovascular disease and related mortality in their later life. In this article we will discuss the results of studies performed in different populations that have shown an interrelationship between obesity and overweight with the presence of preeclampsia. Moreover, we will review some of the common mechanisms that explain this interrelationship, particularly the alterations in the L-arginine/nitric oxide pathway as a crucial mechanism that is common to obesity, preeclampsia and cardiovascular diseases.

State-of-the-Art Diagnosis and Treatment of Hypertension in Pregnancy

Hypertension complicates up to 10% of pregnancies worldwide. Pregnancy hypertension is defined as systolic blood pressure (BP) equal to or greater than 140 mm Hg or diastolic BP equal to or greater than 90 mm Hg, usually on the basis of measurements in office/clinic settings and using various BP devices. Hypertensive disorders of pregnancy are classified into (1) chronic hypertension diagnosed before pregnancy or before 20 weeks' gestation, (2) gestational hypertension diagnosed at equal to or greater than 20 weeks, or (3) preeclampsia, defined restrictively as gestational hypertension with proteinuria or broadly as gestational hypertension with proteinuria or an end-organ manifestation consistent with preeclampsia. Absolute BP values equal to or greater than 140/90 mm Hg are associated with increased maternal and perinatal risks, particularly with preeclampsia. This review focuses on antihypertensive therapy of hypertensive disorders of pregnancy as a specific management strategy. Underpinning this therapy is the need for accurate measurement of BP, agreed-upon classification of pregnancy hypertension, agreed-upon BP thresholds for enhanced surveillance and antihypertensive treatment, and collaborative teamwork in management. Challenges relate to the methodology of studies on which care is based, as well as aspects of the care itself, particularly the unregulated use of home BP monitoring. Pitfalls include the unsubstantiated belief that nifedipine and magnesium sulfate cannot be used together and the perception that severe hypertension and nonsevere hypertension are separate entities rather than lying along a spectrum of BP values. The following must be addressed by future research: guidance for nuanced care as women transition between severe and nonsevere hypertension, personalized antihypertensive therapy, and incorporation of women's values into research priorities and clinical practice when antihypertensive care is chosen.

SOMANZ guidelines for the management of hypertensive disorders of pregnancy 2014

This guideline is an evidence based, practical clinical approach to the management of Hypertensive Disorders of Pregnancy. Since the previous SOMANZ guideline published in 2008, there has been significant international progress towards harmonisation of definitions in relation to both the diagnosis and management of preeclampsia and gestational hypertension. This reflects increasing knowledge of the pathophysiology of these conditions, as well as their clinical manifestations. In addition, the guideline includes the management of chronic hypertension in pregnancy, an approach to screening, advice regarding prevention of hypertensive disorders of pregnancy, and discussion of recurrence risks and long term risk to maternal health. The literature reviewed included the previous SOMANZ Hypertensive Disorders of Pregnancy guideline from 2008 and its reference list, plus all other published National and International Guidelines on this subject. Medline, Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Registry of Controlled Trials (CCRCT), National Institute for Health and Care Excellence (NICE) Evidence Search, and Database of Abstracts and Reviews of Effects (DARE) were searched for literature published between January 2007 and March, 2014.

Blood pressure in healthy pregnancy and factors associated with no mid-trimester blood pressure drop: a prospective cohort study

BACKGROUND

The well-known mid-trimester drop in blood pressure (BP) during normal pregnancy was recently questioned.

OBJECTIVE

To describe longitudinal changes in BP during healthy pregnancies and to investigate factors associated with no mid-trimester drop in BP.

METHODS

A prospective cohort with 158 healthy pregnant women was followed up in a public health care center in Rio de Janeiro, Brazil. We used linear mixed-effects models to estimate longitudinal changes in systolic BP (SBP) and diastolic BP (DBP) during pregnancy. Poisson regression models were performed to identify factors associated with no mid-trimester drop in BP.

RESULTS

Significant mid-trimester increase in SBP (5.6 mm Hg; 95% confidence interval (CI) = 4.6-6.7) and DBP (4.4 mm Hg; 95% CI = 3.4-5.3) was observed in 44.3% and 39.9% of the sample, respectively. Women (37.1%) who had not a mid-trimester SBP drop still had a DBP drop. White skin color (incidence ratio (IR): 1.71; 95% CI = 1.22-2.39), family history of hypertension (IR: 1.93; 95% CI = 1.29-2.89), early pregnancy obesity (IR: 2.29; 95% CI = 1.27-4.11), outside temperature variation (IR: 1.45; 95% CI = 1.00-2.10), and gestational weight gain from the first to second trimester (IR: 1.71; 95% CI = 1.01-2.88 and IR: 2.32; 95% CI = 1.39-3.89 for second and third tertiles) were characteristics associated with no mid-trimester drop in SBP. The same characteristics were associated with no mid-trimester drop in DBP, except family history of hypertension and outside temperature variation.

CONCLUSIONS

Some women without a mid-trimester SBP drop still present a DBP drop. The different patterns of mid-trimester change in BP seem to be determined by preexisting and pregnancy-related factors.

Serum calcium and magnesium levels in women presenting with pre-eclampsia and pregnancy-induced hypertension: a case-control study in the Cape Coast metropolis, Ghana

Background

Hypertensive disorders of pregnancy are important causes of morbidity and mortality. The levels of calcium (Ca²⁺) and magnesium (Mg²⁺) in pregnancy may implicate their possible role in pregnancy-induced hypertension. This study assessed serum Ca²⁺ and Mg²⁺ levels in women with PIH (pregnancy-induced hypertension) and PE (pre-eclampsia), compared to that in normal pregnancy.

Methods

This case–control study was conducted on 380 pregnant women (≥20 weeks gestation) receiving antenatal care at three hospitals in the Cape Coast metropolis, Ghana. This comprised 120 women with PIH, 100 women with PE and 160 healthy, age-matched pregnant women (controls). Demographic, anthropometric, clinical and obstetric data were gathered using an interview-based questionnaire. Venous blood samples were drawn for the estimation of calcium and magnesium.

Results

Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were significantly raised in women with PIH (p < 0.0001) and PE (p < 0.0001). Women with hypertensive disorders (PE and PIH) had significantly lower serum calcium and magnesium levels than those in the control group (p < 0.0001 each). Of those with PIH, SBP correlated positively with BMI (r = 0.575, p < 0.01) and Ca²⁺ correlated positively with Mg²⁺ (r = 0.494, p < 0.01). This was similar amongst the PE group for SBP and BMI as well as for Ca²⁺and Mg²⁺ but was not significant. Multivariate analysis showed that women aged ≥40 years were at a significant risk of developing PIH (OR = 2.14, p = 0.000).

Conclusion

In this study population, serum calcium and magnesium levels are lower in PIH and PE than in normal pregnancy. Mineral supplementation during the antenatal period may influence significantly, the occurrence of hypertensive disorders in pregnancy.

Management of Hypertensive Disorders in Pregnancy

Hypertensive disorders are the most common medical complication of pregnancy, with an incidence of 5-10%, and a common cause of maternal mortality in the USA. Incidence of pre-eclampsia has increased by 25% in the past two decades. In addition to being among the lethal triad, there are likely up to 100 other women who experience ‘near miss’ significant maternal morbidity that stops short of death for every pre-eclampsia-related mortality. The purpose of this review is to present the new task force statement and novel definitions, as well as management approaches to each of the hypertensive disorders in pregnancy. The increased understanding of the pathophysiology of hypertension in pregnancy, as well as advances in medical therapy to minimize risks of fetal toxicity and teratogenicity, will improve our ability to prevent and treat hypertension in pregnancy. Fetal programming and fetal origins of adult disease theories extrapolate the benefit of such therapy to future generations.

Ethnicity, body mass index and risk of pre-eclampsia in a multiethnic New Zealand population

BACKGROUND

Pre-eclampsia rates are reported to vary by ethnicity; however, few studies include body mass index (BMI). Increasing BMI has a dose-dependent relationship with pre-eclampsia, and rates of overweight and obesity as well as ratios of body fat to muscle mass differ between ethnicities. We hypothesised that after adjusting for confounders, including ethnic-specific BMI, ethnicity would not be an independent risk factor for pre-eclampsia.

AIM

To assess independent pre-eclampsia risk factors in a multiethnic New Zealand population.

METHODS

We performed a retrospective cohort analysis of prospectively recorded maternity data from 2006 to 2009 at National Women's Health, Auckland, New Zealand. After exclusion of infants with congenital anomalies and missing data, our final study population was 26 254 singleton pregnancies. Multivariable logistic regression analysis adjusted for ethnicity, BMI, maternal age, parity, smoking, social deprivation, diabetes, chronic hypertension and relevant pre-existing medical conditions was performed.

RESULTS

Independent associations with pre-eclampsia were observed in Chinese (adjusted odds ratio (aOR) 0.56, [95% CI 0.41-0.76]) and Māori (aOR 1.51, [1.16-1.96]) compared with European women. Other independent risk factors for pre-eclampsia were overweight and obesity, nulliparity, type 1 diabetes, chronic hypertension and pre-existing medical conditions.

CONCLUSIONS

Contrary to our hypothesis, we report an independent reduced risk of pre-eclampsia in Chinese and increased risk of pre-eclampsia in Māori women. Prospective studies are required to further explore these relationships. Other independent risk factors are consistent with international literature. Our findings may assist clinicians to stratify risk of pre-eclampsia in clinical practice.

Mid-trimester blood pressure drop in normal pregnancy: myth or reality?

BACKGROUND

Current dogma states that there is a mid-trimester fall in blood pressure (BP) in uncomplicated pregnancy. In the early stages of a longitudinal study of microcirculatory changes in pregnancy, we noted an absence of this mid-trimester fall.

METHOD

We prospectively studied this phenomenon in all our subsequent recruits. From a total of 326 women, 255 primigravid white women normotensive at booking and after delivery were studied. Serial BP measurements were taken under controlled conditions through to 38 weeks gestation. BP measurements by midwives were extracted from the case notes of 51 women within this cohort and analysed to validate the results. SBP progressively increased from the first trimester through to 38 weeks gestation.

RESULTS

The increase from baseline at 13 weeks was significant when compared with measurements at 22 weeks [mean difference: 2.8 mmHg; 95% (confidence interval) CI 1.9-3.7], 28 weeks (mean difference: 5.0 mmHg; 95% CI 3.5-6.5) and 36 weeks (mean difference: 7.7 mmHg; 95% CI 6.2-9.1). DBP showed a nonsignificant dip at 22 weeks (mean difference: -0.12 mmHg; 95% CI -0.92 to 0.68), a nonsignificant increase at 28 weeks (mean difference: 2.0 mmHg; 95% CI 0.80-3.2) and a significant increase at 36 weeks (mean difference: 6.0; 95% CI 4.6-7.3). In the validation cohort, the SBP (P=0.0001) and DBP showed an increasing trend (P=0.0001).

CONCLUSION

BP measured under controlled conditions showed a progressive rise in pregnancy, with no significant mid-trimester drop. The findings were replicated in the routine antenatal clinic measurements.

The use and the user of herbal remedies during pregnancy

BACKGROUND

The physiologic changes that occur during pregnancy can lead to a variety of conditions that can usually be self-treated. There are no licensed medicines for conditions such as morning sickness or insomnia in pregnancy, and evidence from Western countries suggests that patients often resort to using herbal medicines. Research on the health behaviors of pregnant women in the United Kingdom with respect to herbal remedies has not been undertaken.

OBJECTIVE

The objective of this study is to describe the use and the user of herbal remedies during pregnancy and to study the sources of information about herbs used.

DESIGN

The study design was a survey among expectant mothers more than 20 weeks pregnant presenting at an antenatal clinic.

SETTING

The setting was an antenatal clinic and antenatal ultrasound department at Norfolk and Norwich University Hospital. One thousand and thirty-seven (1037) questionnaires were handed out between November 2007 and February 2008.

RESULTS

Five hundred and seventy-eight (578) questionnaires were returned (55.7%). Three hundred and thirty-four (334) of the 578 respondents (57.8%) reported using herbal remedies during pregnancy with a mean of 1.2 remedies per woman (median: 1, range: 0-10). The most commonly used remedies were ginger, cranberry, and raspberry leaf. The most probable user had been pregnant before and had a university degree. "Family and friends" were the most frequently cited source of information about herbal remedies during pregnancy, and more than 75% of the users reportedly did not tell their doctor or midwife about the use.

CONCLUSIONS

A large percentage of the women in the study used herbal remedies during pregnancy--many of them without informing their doctor or midwife. Doctors or midwives should ask pregnant women if they use herbal remedies during pregnancy. Health care personnel should be open to discuss the use of herbal remedies during pregnancy and be able to give balanced information as the use is so widespread.

Relationship between maternal glycaemia and birth weight in glucose-tolerant women from different ethnic groups in New Zealand

AIM

The aim of this study was to compare the population attributable fraction(PAF) for a large baby (> or =4 kg) due to glycaemia, weight and smoking in glucose-tolerant women from different ethnic groups.

METHODS

A retrospective review of screening for gestational diabetes (GDM)and associated birth weight was undertaken in New Zealand European (n= 529), Maori (n= 540) and Pacific (n= 916) women. The proportion with a large baby was compared by 1-h post 50-g glucose challenge test tertile and maternal weight tertile.

RESULTS

Large babies were more common from Pacific and European than Maori women (24.3%, 18.8%, 8.9%, respectively; P<0.001). Birth weight increased significantly with increasing glucose among Pacific women (P<0.001) even after adjusting for maternal weight and other confounders. The risk of having a large baby was 2.56 (1.82-3.60)-fold greater in women in the highest maternal weight tertile (> or =84 kg), with a significantly greater PAF in Pacific women(27.2%, 12.9%, 16.4%, respectively; P<0.001). The odds ratio (OR) of having a large baby increased with even mildly elevated maternal 1-h glucose concentrations [OR for 5.6-6.2 mmol/l: 1.54 (1.11-2.14); for > or =6.3 mmol/l: 2.06 (1.50-2.82)], with no ethnic differences in PAF (11.1-11.8%, 16.7-18.7%, respectively). Smoking and being Maori were associated with smaller babies.

CONCLUSIONS

Increased maternal weight and glycaemia are associated with a greater proportion of large babies among glucose-tolerant women. Growth of Pacific babies may be more sensitive to a higher maternal glucose when the mother is obese.

Routine investigations might be useful in pre-eclampsia, but not in gestational hypertension

BACKGROUND

Women referred to secondary care with suspected pregnancy-induced hypertension (PIH) are commonly investigated with blood tests and cardiotocography (CTG), regardless of the clinical severity of their condition. Over-investigation might lead to inappropriate intervention.

AIMS

To investigate how often abnormal blood test and CTG results occur in women with pre-eclampsia and gestational hypertension and in women who do not have pregnancy-induced hypertension.

METHODS

Retrospective case note review of 526 consecutive women referred with suspected pregnancy-induced hypertension to a district hospital. The frequency of abnormal test results and the pregnancy outcomes were analysed according to clinical classification.

RESULTS

36% of women referred did not meet the clinical criteria for a diagnosis of pregnancy-induced hypertension. Abnormalities of platelet count and/or liver function were seen in 11% of women with pre-eclampsia and in less than 2% of women with gestational hypertension and in a similar proportion of women who did not have pregnancy-induced hypertension. Gestational hypertension was associated with increased induction and caesarean birth rates, but not with low birthweight or preterm delivery. Progression from gestational hypertension to pre-eclampsia was not predicted by blood test abnormalities. Support for the routine use of antenatal CTG was not found.

CONCLUSIONS

A clinical diagnosis of pregnancy-induced hypertension should be confirmed before blood tests are ordered. The incidence of test abnormalities was only increased in pre-eclampsia and in gestational hypertension before term. CTG might only be of use in selected cases.

Cross sectional study of automated blood pressure measurements throughout pregnancy

OBJECTIVE

To generate reliable new reference ranges for pregnancy blood pressure from a large population.

DESIGN

A prospective cross sectional study.

SETTING

Obstetric outpatient clinic, Zurich University Hospital.

SAMPLE

Accurately dateable singleton pregnancies (Caucasian: n= 3234; Asian [predominantly from Sri Lanka, Thailand and the Philippines]: n= 577; Black n= 212).

METHODS

Between January 1996 and February 2000 blood pressure was determined in 4023 pregnant women using an oscillometric automated device (Dinamap) according to British Hypertension Society recommendations. Women receiving antihypertensive medication were excluded.

MAIN OUTCOME MEASURE

Blood pressure.

RESULTS

Only the means of duplicate measures at the booking visit (5-42 weeks) were used in the analysis. Mean blood pressure decreased from early to mid pregnancy before increasing to levels 4 mmHg higher at term than in early pregnancy. Values >130/80 and <90/50 mmHg were above the 95th and below the 5th centiles, respectively. Parity, age and body mass index were significant determinants in Caucasians. Blood pressure was slightly lower in Asians and Blacks.

CONCLUSIONS

The current World Health Organisation definition of high diastolic blood pressure (>or=90 mmHg on two occasions) reflects values >2 standard deviations from the mean. This may be too conservative as threshold for detecting women at risk of pre-eclampsia. Further studies are required to determine the prognostic implications of gestational values >or=95th centile (>or=130/80 mmHg) and <or=5th centile (<or=90/50 mmHg).

Evaluation of a definition of pre-eclampsia

OBJECTIVES

To determine: 1. whether an alternative definition of gestational hypertension and pre-eclampsia stratifies women according to their risk of maternal and fetal complications; 2. whether pregnancy outcome in women with gestational hypertension differs in the presence or absence of '+' proteinuria; and 3. whether a blood pressure rise of > or = 30/15 mmHg during pregnancy is associated with adverse outcome in women who remain normotensive.

DESIGN

Prospective, nested case-control study.

SETTING

Community based.

POPULATION

Healthy, nulliparous women (n = 1496).

METHODS

Women recruited into a study investigating serum markers predictive of pre-eclampsia were classified as having gestational hypertension (systolic blood pressure > or = 140 mmHg with a rise of > or = 30 mmHg and/or diastolic blood pressure > or = 90 mmHg with a rise of > or = 15 mmHg) or pre-eclampsia (gestational hypertension plus proteinuria > or = 2+on dipstick or > 0.3 g/24 h). Maternal and fetal complications in gestational hypertension or pre-eclampsia were compared with a control group of 223 randomly selected normotensive women. The main outcome measures were severe maternal disease, preterm birth and small for gestational age infant.

RESULTS

A stepwise increase in adverse maternal and fetal outcomes occurred in gestational hypertension (n = 117, 7.8%) and pre-eclampsia (n = 71, 4.8%). Severe maternal disease developed in 26.5% (21.4% severe hypertension alone, 5.1% multisystem disease) of women with gestational hypertension and 63.4% (21.1% severe hypertension alone, 42.3% multisystem disease) of women with pre-eclampsia (OR 4.8; 95% CI 2.4-9.5). Preterm birth and small for gestational age infants were more frequent in gestational hypertension (OR 1.7; 95% CI 0.5-5.4, and OR 2.0; 95% CI 1.0-3.7, respectively) and pre-eclampsia (OR 14.6; 95% CI 5.8-37.8, and OR 2.6; 95% CI 1.2-5.3) than in the normotensive group. Among women with gestational hypertension severe maternal disease was more common in women with '+' proteinuria (41.7%) than in those with no proteinuria (15.9%): OR 3.8; 95% CI 1.5-9.8. Pregnancies were uncomplicated in the 27% of normotensive women who had a rise of > or = 30 mmHg systolic blood pressure and/or > or = 15 mmHg rise in diastolic blood pressure.

CONCLUSIONS

In the nulliparous population studied our definition of gestational hypertension and pre-eclampsia identified women at increasing risk of maternal and fetal complications. In gestational hypertension, the presence of proteinuria '+' was associated with a 3.8-fold increase in severe maternal disease. Normotensive women who have a rise in blood pressure > or = 30/15 mmHg had uncomplicated pregnancies.

The changing pattern of eclampsia over a 60-year period

OBJECTIVE

To determine changes in the incidence and pattern of eclampsia within the same geographical area over a 60-year period.

DESIGN

A retrospective, descriptive study of 1259 consecutive women classified, at the time, as having had an eclamptic convulsion between the years 1931 and 1990.

SETTING

A large city centre teaching hospital and the surrounding catchment area.

MAIN OUTCOME MEASURES

The changes in the incidence and timing of the convulsion and the outcomes for the mother and baby.

RESULTS

Over the study period, the incidence of eclampsia fell by more than 90%, from 74.1/10,000 in the 1930s to 7.2/10,000 in the 1980s. Most of the reduction occurred over the first four decades, with little change in the last 20 years. Overall, 44% of the cases of eclampsia occurred in the antenatal period, 33% intrapartum and 23% postpartum. Since the biggest decreases were seen in the incidence of antenatal and particularly intrapartum eclampsia, there has been a relative increase in the proportion of eclampsia occurring postpartum. Maternal death from eclampsia occurred in 15.1% of cases between 1931 and 1940, 13.4% between 1941 and 1950, but fell dramatically to < or = 3.9% after 1950. There has been no maternal death since 1964. Apart from the first decade, postpartum eclampsia was associated with significantly less risk of death to the mother throughout the study period. Perinatal death rate has fallen steadily from 432.6/1000 cases of eclampsia between 1931 and 1940 over the first three decades, to 168.7/1000 between 1961 and 1970. There has been little change since, although a lower proportion of neonatal deaths occurred as stillbirths.

CONCLUSIONS

We found a significant reduction in both the incidence of eclampsia and associated morbidity in this population over the last 60 years. This has occurred in association with the introduction of the National Health Service, widespread antenatal care for all and a general improvement in health and welfare. Any further reduction in the incidence in the UK may be difficult to achieve. Since the incidence of eclampsia is now low, efforts should perhaps be directed at minimising the morbidity associated with severe pre-eclampsia rather than prevention of convulsions.

What happens to women with preeclampsia? Microalbuminuria and hypertension following preeclampsia

There is little published data on the incidence of remote hypertension, microalbuminuria (a possible marker of remote cardiovascular events) and diabetes following preeclampsia. This is of particular importance in Pacific Island populations as they have a high rate of preeclampsia, non-insulin dependent diabetes and cardiovascular related deaths. The aim of this study was to compare the rate of microalbuminuria and hypertension in 50 Samoan women with past preeclampsia (cases) with 50 Samoan women who did not have past preeclampsia (controls). Forty per cent of cases were hypertensive at follow-up compared to 2% in the control group (p < 0.0001). Microalbuminuria or proteinuria occurred in 40% of women with past preeclampsia and 18% of controls (p < 0.02). Half of the cases with microalbuminuria were hypertensive. No case or control had an elevated fructosamine, suggesting that current diabetes was an unlikely explanation for the microalbuminuria. We conclude that Samoan women with past preeclampsia are at increased risk of developing chronic hypertension and microalbuminuria. The significance of the microalbuminuria after preeclampsia is not known, but it may be a marker of either remote cardiovascular morbidity or non-insulin dependent diabetes. This study raises longterm health implications for women with preeclampsia.