Prediction of hypertensive disorders after screening at 36 weeks' gestation: comparison of angiogenic markers with competing-risks model

OBJECTIVE

To compare the performance at 35 + 0 to 36 + 6 weeks' gestation of screening for delivery with pre-eclampsia (PE) at various timepoints, using one of three approaches: placental growth factor (PlGF) concentration, soluble fms-like tyrosine kinase-1 (sFlt-1) to PlGF concentration ratio, or the competing-risks model, which combines maternal risk factors with biomarkers to estimate patient-specific risk.

METHODS

This was a prospective observational study of women attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation at one of two maternity hospitals in England between 2016 and 2022. During the visit, maternal demographic characteristics and medical history were recorded and serum PlGF, serum sFlt-1 and mean arterial pressure (MAP) were measured. Detection rates (DRs) were evaluated for delivery with PE (defined as per American College of Obstetricians and Gynecologists 2019 criteria) within 1 week, within 2 weeks or at any time after screening, using the following strategies: (i) low PlGF (< 10th percentile); (ii) high sFlt-1/PlGF ratio (> 90th percentile); or (iii) the competing-risks model, in which maternal factors were combined with multiples of the median values of PlGF ('single test'), PlGF and sFlt-1 ('double test') or PlGF, sFlt-1 and MAP ('triple test'). Risk cut-offs corresponded to a screen-positive rate of 10%. DRs were compared between tests.

RESULTS

Of 34 782 pregnancies, 831 (2.4%) developed PE. In screening for delivery with PE at any time from assessment, the DR at 10% screen-positive rate was 47% by low PlGF alone, 54% by the single test, 55% by high sFlt-1/PlGF ratio, 61% by the double test and 68% by the triple test. In screening for delivery with PE within 2 weeks from assessment, the respective values were 67%, 74%, 74%, 80% and 87%. In screening for delivery with PE within 1 week from assessment, the respective values were 77%, 81%, 85%, 88% and 91%. For prediction of PE at any time, the DR was significantly higher with the triple test compared to PlGF alone or the sFlt-1/PlGF ratio, with a DR difference (95% CI) of 20.1% (16.7-23.0%) and 12.4% (9.7-15.3%), respectively. Similar results were seen for prediction of PE within 2 weeks (20.6% (14.9-26.8%) and 12.9% (7.7-17.5%), respectively) and prediction of PE within 1 week (13.5% (5.4-21.6%) and 5.4% (0.0-10.8%), respectively). The double test was superior to the sFlt-1/PlGF ratio and the single test was superior to PlGF alone in the prediction of PE within 2 weeks and at any time from assessment, but not within 1 week of assessment.

CONCLUSION

At 35 + 0 to 36 + 6 weeks' gestation, the performance of screening for PE by the competing-risks model triple test is superior to that of PlGF alone or the sFlt-1/PlGF ratio for the development of disease within 1 week, within 2 weeks and at any time from screening. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Incidence of pre-eclampsia: effect of deprivation

OBJECTIVES

To examine the relationship between the English index of multiple deprivation (IMD) and the incidence of pre-eclampsia (PE), evaluate the distribution of IMD in a cohort of ethnically diverse pregnant women in South East England and assess whether IMD improves the prediction of PE compared with that provided by the 'history-only' competing-risks model (based on maternal characteristics and medical history).

METHODS

This was a prospective, observational study of 159 125 women with a singleton pregnancy who attended their first routine hospital visit at 11 + 0 to 13 + 6 weeks' gestation in two maternity hospitals in the UK. The inclusion criteria were delivery at ≥ 24 weeks' gestation of babies without major abnormality. Participants completed a questionnaire on demographic characteristics and obstetric and medical history, which was then reviewed by a doctor together with the woman. Patients were asked to self-identify as white, black, South Asian, East Asian or mixed race. IMD was used as a measure of socioeconomic status, which takes into account income, employment, education, skills and training, health and disability, crime, barriers to housing and services, and living environment. Each neighborhood is ranked according to their level of deprivation relative to that of other areas into one of five equal groups, with Quintile 1 containing the 20% most deprived areas and Quintile 5 containing the 20% least deprived areas. IMD was assigned based on a woman's postcode. Risk factors for PE and its incidence were assessed across IMD using chi-square test or t-test, as appropriate. The relationship between IMD and gestational age at delivery with PE was evaluated by fitting parametric survival models for IMD alone, IMD combined with race and IMD combined with the Fetal Medicine Foundation history-only competing-risks model.

RESULTS

The incidence of PE (n = 4088, 2.6%) increased progressively across IMD quintiles, from 2.0% in Quintile 5 (least deprived) to 3.0% in Quintile 1 (most deprived). Compared with white women and those in other racial groups, black women had a higher incidence of PE (4.8%), were less often in IMD Quintiles 4 and 5, and were more often in IMD Quintiles 1 and 2. None of the IMD quintiles improved the prediction of PE compared with that provided by the history-only competing-risks model (which includes race). The history-only competing-risks model with vs without IMD had a similar detection rate for delivery with PE at < 37 weeks' gestation (44.1% (95% CI, 41.1-47.2%) vs 43.9% (95% CI, 40.1-47.0%)) and at any gestational age (35.2% (95% CI, 33.8-36.7%) vs 35.1% (95% CI, 33.7-36.6%)), at a 10% screen-positive rate.

CONCLUSIONS

The incidence of PE is higher in women living in the most deprived areas in South East England and in black women (vs those of other racial groups), who also live in areas of higher deprivation. However, in screening for PE, inclusion of IMD does not improve the prediction of PE provided by race and other maternal characteristics and elements of medical history. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Competing-risks model for pre-eclampsia and adverse pregnancy outcomes

OBJECTIVE

The competing-risks model for assessment of risk for pre-eclampsia (PE) at 35-37 weeks' gestation identifies the majority of women who are at high risk of subsequent delivery with PE. We aimed to examine the incidence and relative risk of adverse pregnancy outcomes in patient groups stratified according to the estimated risk of delivery with PE.

METHODS

This was a prospective non-interventional, observational study in women with a singleton pregnancy attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. The risk of delivery with PE for each patient in the study population was estimated using the competing-risks model, combining the prior distribution of gestational age at delivery with PE and the likelihood from multiples of the median values of mean arterial pressure, placental growth factor and soluble fms-like tyrosine kinase-1. The patients were assigned to one of the following five risk categories: Group A, ≥ 1 in 2; Group B, 1 in 5 to 1 in 3; Group C, 1 in 20 to 1 in 6; Group D, 1 in 50 to 1 in 21; and Group E, < 1 in 50. The outcome measures were delivery with PE, gestational hypertension (GH), small-for-gestational age (SGA) at birth, delivery by Cesarean section, stillbirth, neonatal death, perinatal death and admission to the neonatal unit (NNU) for at least 48 h. In each risk category, the proportion of women with each adverse outcome was determined and relative risks (RR) were calculated as compared with the lowest-risk Group E.

RESULTS

In the study population of 29 035 women, 1.6%, 2.7%, 8.2%, 9.8% and 77.8% were categorized into Groups A, B, C, D and E, respectively. Compared with women in Group E, women in the higher-risk groups were more likely to have an adverse outcome. The RR of delivery with PE in Group A compared with Group E was 65.5 (95% CI, 54.1-79.1) and the respective values were 11.9 (95% CI, 9.1-15.5) for GH, 1.8 (95% CI, 1.5-2.1) for delivery by emergency Cesarean section, 1.5 (95% CI, 1.2-1.8) for delivery by elective Cesarean section, 8.9 (95% CI, 7.4-10.8) for SGA with birth weight < 3^rd percentile, 4.8 (95% CI, 4.3-5.4) for SGA with birth weight < 10^th percentile, 5.3 (95% CI, 1.4-20.5) for stillbirth and 3.4 (95% CI, 2.8-4.2) for NNU admission for ≥ 48 h. The RR for these pregnancy complications in higher-risk groups (vs Group E) was particularly high for cases with delivery within 2 weeks after assessment. In terms of SGA, both for birth weight < 10^th and < 3^rd percentiles, the trend in all cases was stronger than that observed when the analysis was confined to normotensive pregnancies. The rates of neonatal death were too small to allow meaningful comparisons between risk groups.

CONCLUSION

Pregnant women identified by the competing-risks model to be at high risk of PE are also at increased risk of GH, Cesarean section, stillbirth, SGA and NNU admission for ≥ 48 h. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal and perinatal outcomes of SARS-CoV-2 infection in unvaccinated pregnancies during Delta and Omicron waves

OBJECTIVE

There is little evidence related to the effects of the Omicron severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant on pregnancy outcomes, particularly in unvaccinated women. This study aimed to compare pregnancy outcomes of unvaccinated women infected with SARS-CoV-2 during the pre-Delta, Delta and Omicron waves.

METHODS

This was a retrospective cohort study conducted at two tertiary care facilities: Sancaktepe Training and Research Hospital, Istanbul, Turkey, and St George's University Hospitals NHS Foundation Trust, London, UK. Included were women who tested positive for SARS-CoV-2 by real-time reverse-transcription polymerase chain reaction (RT-PCR) during pregnancy, between 1 April 2020 and 14 February 2022. The cohort was divided into three periods according to the date of their positive RT-PCR test: (i) pre-Delta (1 April 2020 to 8 June 2021 in Turkey, and 1 April 2020 to 31 July 2021 in the UK), (ii) Delta (9 June 2021 to 27 December 2021 in Turkey, and 1 August 2021 to 27 December 2021 in the UK) and (iii) Omicron (after 27 December 2021 in both Turkey and the UK). Baseline data collected included maternal age, parity, body mass index, gestational age at diagnosis and comorbidities. The primary outcome was the need for oxygen supplementation, classified as oxygen support via nasal cannula or breather mask, non-invasive mechanical ventilation with continuous positive airway pressure (CPAP) or high-flow oxygen, mechanical ventilation with intubation, or extracorporeal membrane oxygenation (ECMO). Inferences were made after balancing of confounders, using an evolutionary search algorithm. Selected confounders were maternal age, body mass index and gestational age at diagnosis of infection.

RESULTS

During the study period, 1286 unvaccinated pregnant women with RT-PCR-proven SARS-CoV-2 infection were identified, comprising 870 cases during the pre-Delta period, 339 during the Delta wave and 77 during the Omicron wave. In the confounder-balanced cohort, infection during the Delta wave vs during the pre-Delta period was associated with increased need for nasal oxygen support (risk ratio (RR), 2.53 (95% CI, 1.75-3.65); P < 0.001), CPAP or high-flow oxygen (RR, 2.50 (95% CI, 1.37-4.56); P = 0.002), mechanical ventilation (RR, 4.20 (95% CI, 1.60-11.0); P = 0.003) and ECMO (RR, 11.0 (95% CI, 1.43-84.7); P = 0.021). The maternal mortality rate was 3.6-fold higher during the Delta wave compared to the pre-Delta period (5.3% vs 1.5%, P = 0.010). Infection during the Omicron wave was associated with a similar need for nasal oxygen support (RR, 0.62 (95% CI, 0.25-1.55); P = 0.251), CPAP or high-flow oxygen (RR, 1.07 (95% CI, 0.36-3.12); P = 0.906) and mechanical ventilation (RR, 0.44 (95% CI, 0.06-3.45); P = 0.438) with that in the pre-Delta period. The maternal mortality rate was similar during the Omicron wave and the pre-Delta period (1.3% vs 1.3%, P = 0.999). The need for nasal oxygen support during the Omicron wave was significantly lower compared to the Delta wave (RR, 0.26 (95% CI, 0.11-0.64); P = 0.003). Perinatal outcomes were available for a subset of the confounder-balanced cohort. Preterm birth before 34 weeks' gestation was significantly increased during the Delta wave compared with the pre-Delta period (15.4% vs 4.9%, P < 0.001).

CONCLUSIONS

Among unvaccinated pregnant women, SARS-CoV-2 infection during the Delta wave, in comparison to the pre-Delta period, was associated with increased requirement for oxygen support (including ECMO) and higher maternal mortality. Disease severity and pregnancy complications were similar between the Omicron wave and pre-Delta period. SARS-CoV-2 infection of unvaccinated pregnant women carries considerable risks of morbidity and mortality regardless of variant, and vaccination remains key. Miscommunication of the risks of Omicron infection may impact adversely vaccination uptake among pregnant women, who are at increased risk of complications related to SARS-CoV-2. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The impact of pre-eclampsia definitions on the identification of adverse outcome risk in hypertensive pregnancy - analyses from the CHIPS trial (Control of Hypertension in Pregnancy Study)

OBJECTIVE

To examine the association between pre-eclampsia definition and pregnancy outcome.

DESIGN

Secondary analysis of Control of Hypertension in Pregnancy Study (CHIPS) trial data.

SETTING

International multicentre randomised controlled trial (RCT).

POPULATION

In all, 987 women with non-severe non-proteinuric pregnancy hypertension.

METHODS

We evaluated the association between pre-eclampsia definitions and adverse pregnancy outcomes, stratified by hypertension type and blood pressure control.

MAIN OUTCOME MEASURES

Main CHIPS trial outcomes: primary (perinatal loss or high-level neonatal care for >48 hours), secondary (serious maternal complications), birthweight <10th centile, severe maternal hypertension, delivery at <34 or <37 weeks, and maternal hospitalisation before birth.

RESULTS

Of 979/987 women with informative data, 280 (28.6%) progressed to pre-eclampsia defined restrictively by new proteinuria, and 471 (48.1%) to pre-eclampsia defined broadly as proteinuria or one/more maternal symptoms, signs or abnormal laboratory tests. The broad (versus restrictive) definition had significantly higher sensitivities (range 62-79% versus 36-50%), lower specificities (range 53-65% versus 72-82%), and similar or higher diagnostic odds ratios and 'true-positive' to 'false-positive' ratios. Stratified analyses showed similar results. Addition of available fetoplacental manifestations (stillbirth or birthweight <10th centile) to the broad pre-eclampsia definition improved sensitivity (74-87%).

CONCLUSIONS

A broad (versus restrictive) pre-eclampsia definition better identifies women who develop adverse pregnancy outcomes. These findings should be replicated in a prospective study within routine healthcare to ensure that the anticipated increase in surveillance and intervention in a larger number of women with pre-eclampsia is associated with improved outcomes, reasonable costs and congruence with women's values.

TWEETABLE ABSTRACT

A broad (versus restrictive) pre-eclampsia definition better identifies the risk of adverse pregnancy outcomes.

Maternity services in the UK during the coronavirus disease 2019 pandemic: a national survey of modifications to standard care

OBJECTIVE

To explore the modifications to maternity services across the UK, in response to the coronavirus disease 2019 (COVID-19) pandemic, in the context of the pandemic guidance issued by the Royal College of Obstetricians and Gynaecologists (RCOG), Royal College of Midwives (RCM) and NHS England.

DESIGN

National survey.

SETTING

UK maternity services during the COVID-19 pandemic.

POPULATION OR SAMPLE

Healthcare professionals working within maternity services.

METHODS

A national electronic survey was developed to investigate local modifications to general and specialist maternity care during the COVID-19 pandemic, in the context of the contemporaneous national pandemic guidance. After a pilot phase, the survey was distributed through professional networks by the RCOG and co-authors. The survey results were presented descriptively in tabular and graphic formats, with proportions compared using chi-square tests.

MAIN OUTCOME MEASURES

Service modifications made during the pandemic.

RESULTS

A total of 81 respondent sites, 42% of the 194 obstetric units in the UK, were included. They reported substantial and heterogeneous maternity service modifications. Seventy percent of units reported a reduction in antenatal appointments and 56% reported a reduction in postnatal appointments; 89% reported using remote consultation methods. A change to screening pathways for gestational diabetes mellitus was reported by 70%, and 59% had temporarily removed the offer of births at home or in a midwife-led unit. A reduction in emergency antenatal presentations was experienced by 86% of units.

CONCLUSIONS

This national survey documents the extensive impact of the COVID-19 pandemic on maternity services in the UK. More research is needed to understand the impact on maternity outcomes and experience.

TWEETABLE ABSTRACT

A national survey showed that UK maternity services were modified extensively and heterogeneously in response to COVID-19.

A core outcome set for pre-eclampsia research: an international consensus development study

OBJECTIVE

To develop a core outcome set for pre-eclampsia.

DESIGN

Consensus development study.

SETTING

International.

POPULATION

Two hundred and eight-one healthcare professionals, 41 researchers and 110 patients, representing 56 countries, participated.

METHODS

Modified Delphi method and Modified Nominal Group Technique.

RESULTS

A long-list of 116 potential core outcomes was developed by combining the outcomes reported in 79 pre-eclampsia trials with those derived from thematic analysis of 30 in-depth interviews of women with lived experience of pre-eclampsia. Forty-seven consensus outcomes were identified from the Delphi process following which 14 maternal and eight offspring core outcomes were agreed at the consensus development meeting. Maternal core outcomes: death, eclampsia, stroke, cortical blindness, retinal detachment, pulmonary oedema, acute kidney injury, liver haematoma or rupture, abruption, postpartum haemorrhage, raised liver enzymes, low platelets, admission to intensive care required, and intubation and ventilation. Offspring core outcomes: stillbirth, gestational age at delivery, birthweight, small-for-gestational-age, neonatal mortality, seizures, admission to neonatal unit required and respiratory support.

CONCLUSIONS

The core outcome set for pre-eclampsia should underpin future randomised trials and systematic reviews. Such implementation should ensure that future research holds the necessary reach and relevance to inform clinical practice, enhance women's care and improve the outcomes of pregnant women and their babies.

TWEETABLE ABSTRACT

281 healthcare professionals, 41 researchers and 110 women have developed #preeclampsia core outcomes @HOPEoutcomes @jamesmnduffy. [Correction added on 29 June 2020, after first online publication: the order has been corrected.].

Can risk prediction models help us individualise stillbirth prevention? A systematic review and critical appraisal of published risk models

BACKGROUND

Stillbirth prevention is an international priority - risk prediction models could individualise care and reduce unnecessary intervention, but their use requires evaluation.

OBJECTIVES

To identify risk prediction models for stillbirth, and assess their potential accuracy and clinical benefit in practice.

SEARCH STRATEGY

MEDLINE, Embase, DH-DATA and AMED databases were searched from inception to June 2019 using terms relevant to stillbirth, perinatal mortality and prediction models. The search was compliant with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines.

SELECTION CRITERIA

Studies developing and/or validating prediction models for risk of stillbirth developed for application during pregnancy.

DATA COLLECTION AND ANALYSIS

Study screening and data extraction were conducted in duplicate, using the CHARMS checklist. Risk of bias was appraised using the PROBAST tool.

RESULTS

The search identified 2751 citations. Fourteen studies reporting development of 69 models were included. Variables consistently included were: ethnicity, body mass index, uterine artery Doppler, pregnancy-associated plasma protein and placental growth factor. For almost all models there were significant concerns about risk of bias. Apparent model performance (i.e. in the development dataset) was highest in models developed for use later in pregnancy and including maternal characteristics, and ultrasound and biochemical variables, but few were internally validated and none were externally validated.

CONCLUSIONS

Almost all models identified were at high risk of bias. There are first-trimester models of possible clinical benefit in early risk stratification; these require validation and clinical evaluation. There were few later pregnancy models but, if validated, these could be most relevant to individualised discussions around timing of birth.

TWEETABLE ABSTRACT

Prediction models using maternal factors, blood tests and ultrasound could individualise stillbirth prevention, but existing models are at high risk of bias.

Pseudotumor cerebri syndrome with different types of hormonal contraceptives in women of child-bearing age

BACKGROUND AND PURPOSE

There is a lack of comparative safety data on the risk of pseudotumor cerebri syndrome (PTCS) associated with different hormonal contraceptives. We sought to quantify the risk of PTCS associated with eight different types of hormonal contraceptives compared with oral levonorgestrel.

METHODS

We conducted a retrospective cohort study, with a case-control analysis of 4 871 504 women aged 15-45 years in the period 2008-2015, using IQVIA Ambulatory Electronic Medical Records data in the USA. Patients who used nine different contraceptive agents including intrauterine levonorgestrel, medroxyprogesterone injection, etonogestrel/ethinyl estradiol vaginal ring and combination oral contraceptives (COCs) that contained ethinyl estradiol and the progestins levonorgestrel, norgestimate, desogestrel, norethindrone and drospirenone, were included. Diagnosis of PTCS was defined using the first International Classification of Diseases, 9th or 10th revision, code for intracranial hypertension in patients who had also received an imaging code in the 30 days prior to the index date.

RESULTS

A total of 3323 PTCS cases and 13 292 matched controls were identified. No increase in risk was found when analysing intrauterine levonorgestrel or COCs containing desogestrel, norethindrone, drospirenone, norgestimate or norgestrel versus COC levonorgestrel. The adjusted incidence rate ratio for etonogestrel/etonogestrel/ethinyl estradiol vaginal ring and medroxyprogesterone suspension compared with levonorgestrel COC was 4.45 [95% confidence interval (CI) 1.98-9.96] and 2.20 (95% CI 1.33-3.64), respectively.

CONCLUSIONS

This study found an elevated risk for PTCS among users of etonogestrel vaginal ring and medroxyprogesterone suspension when compared with oral levonorgestrel. Future studies are needed to confirm these findings.

Research priority setting in women's health: a systematic review

BACKGROUND

Developing a shared agenda is an important step in ensuring future research has the necessary relevance.

OBJECTIVE

To characterise research priority setting partnerships (PSPs) relevant to women's health.

SEARCH STRATEGY

Included studies were identified by searching MEDLINE and the James Lind Alliance (JLA) database.

SELECTION CRITERIA

Priority setting partnerships using formal consensus methods.

DATA COLLECTION AND ANALYSIS

Descriptive narrative to describe the study characteristics, methods, and results.

MAIN RESULTS

Ten national and two international PSPs were identified. All PSPs used the JLA method to identify research priorities. Nine PSPs had published a protocol. Potential research uncertainties were gathered from guidelines (two studies), Cochrane reviews (five studies), and surveys (12 studies). The number of healthcare professionals (31-287), patients (44-932), and others (33-139) who responded to the survey, and the number of uncertainties submitted (52-4767) varied. All PSPs entered confirmed research uncertainties (39-104) into interim priority setting surveys and healthcare professionals (31-287), patients (44-932), and others (33-139) responded. All PSPs entered a short list of research uncertainties into a consensus development meeting, which enabled healthcare professionals (six to 21), patients (eight to 14), and others (two to 13) to identify research priorities (ten to 15). Four PSPs have published their results.

CONCLUSION

Future research priority setting studies should publish a protocol, use formal consensus development methods, and ensure their methods and results are comprehensively reported.

TWEETABLE ABSTRACT

Research published in @BJOGtweets highlights future research priorities across women's health, including @FertilityTop10, @jamesmnduffy.

Do labetalol and methyldopa have different effects on pregnancy outcome? Analysis of data from the Control of Hypertension In Pregnancy Study (CHIPS) trial

OBJECTIVE

To compare pregnancy outcomes, accounting for allocated group, between methyldopa-treated and labetalol-treated women in the CHIPS Trial (ISRCTN 71416914) of 'less tight' versus 'tight' control of pregnancy hypertension.

DESIGN

Secondary analysis of CHIPS Trial cohort.

SETTING

International randomised controlled trial (94 sites, 15 countries).

POPULATION OR SAMPLE

Of 987 CHIPS recruits, 481/566 (85.0%) women treated with antihypertensive therapy at randomisation. Of 981 (99.4%) women followed to delivery, 656/745 (88.1%) treated postrandomisation.

METHODS

Logistic regression to compare outcomes among women who took methyldopa or labetalol, adjusted for the influence of baseline factors.

MAIN OUTCOME MEASURES

CHIPS primary (perinatal loss or high level neonatal care for >48 hours) and secondary (serious maternal complications) outcomes, birthweight <10th centile, severe maternal hypertension, pre-eclampsia and delivery at <34 or <37 weeks.

RESULTS

Methyldopa and labetalol were used commonly at randomisation (243/987, 24.6% and 238/987, 24.6%, respectively) and post-randomisation (224/981, 22.8% and 433/981, 44.1%, respectively). Following adjusted analyses, methyldopa (versus labetalol) at randomisation was associated with fewer babies with birthweight <10th centile [adjusted odds ratio (aOR) 0.48; 95% CI 0.20-0.87]. Methyldopa (versus labetalol) postrandomisation was associated with fewer CHIPS primary outcomes (aOR 0.64; 95% CI 0.40-1.00), birthweight <10th centile (aOR 0.54; 95% CI 0.32-0.92), severe hypertension (aOR 0.51; 95% CI 0.31-0.83), pre-eclampsia (aOR 0.55; 95% CI 0.36-0.85), and delivery at <34 weeks (aOR 0.53; 95% CI 0.29-0.96) or <37 weeks (aOR 0.55; 95% CI 0.35-0.85).

CONCLUSION

These nonrandomised comparisons are subject to residual confounding, but women treated with methyldopa (versus labetalol), particularly those with pre-existing hypertension, may have had better outcomes.

TWEETABLE ABSTRACT

There was no evidence that women treated with methyldopa versus labetalol had worse outcomes.

Oral antihypertensive therapy for severe hypertension in pregnancy and postpartum: a systematic review

BACKGROUND

Pregnant and postpartum women with severe hypertension are at increased risk of stroke and require blood pressure (BP) reduction. Parenteral antihypertensives have been most commonly studied, but oral agents would be ideal for use in busy and resource-constrained settings.

OBJECTIVES

To review systematically, the effectiveness of oral antihypertensive agents for treatment of severe pregnancy/postpartum hypertension.

SEARCH STRATEGY

A systematic search of MEDLINE, EMBASE and the Cochrane Library was performed.

SELECTION CRITERIA

Randomised controlled trials in pregnancy and postpartum with at least one arm consisting of a single oral antihypertensive agent to treat systolic BP ≥ 160 mmHg and/or diastolic BP ≥ 110 mmHg.

DATA COLLECTION AND ANALYSIS

Cochrane RevMan 5.1 was used to calculate relative risk (RR) and weighted mean difference by random effects.

MAIN RESULTS

We identified 15 randomised controlled trials (915 women) in pregnancy and one postpartum trial. Most trials in pregnancy compared oral/sublingual nifedipine capsules (8-10 mg) with another agent, usually parenteral hydralazine or labetalol. Nifedipine achieved treatment success in most women, similar to hydralazine (84% with nifedipine; relative risk [RR] 1.07, 95% confidence interval [95% CI] 0.98-1.17) or labetalol (100% with nifedipine; RR 1.02, 95% CI 0.95-1.09). Less than 2% of women treated with nifedipine experienced hypotension. There were no differences in adverse maternal or fetal outcomes. Target BP was achieved ~ 50% of the time with oral labetalol (100 mg) or methyldopa (250 mg) (47% labetelol versus 56% methyldopa; RR 0.85 95% CI 0.54-1.33).

CONCLUSIONS

Oral nifedipine, and possibly labetalol and methyldopa, are suitable options for treatment of severe hypertension in pregnancy/postpartum.

OS082. CHIPS-Child: Testing the developmental origins hypothesis

INTRODUCTION

CHIPS-Child is a natural test of the Developmental Origins of Health and Disease hypothesis (DOHaD) [1,2]. Reduced fetal growth rate is associated with adult cardiovascular risk markers (e.g., obesity) and disease [3,4]. Evidence worldwide indicates that this relationship is independent of birth weight. The leading theory describes 'developmental programming'in utero leading to permanent alteration of the fetal genome. While those changes are adaptive in utero, they may be maladaptive postnatally.

OBJECTIVES

To directly test, for the first time in humans, whether differential blood pressure (BP) control in pregnancy has developmental programming effects, independent of birth weight. We predict that, like famine or protein malnutrition, 'tight' (vs. 'less tight') control of maternal BP will be associated with fetal under-nutrition and effects will be consistent with developmental programming.

METHODS

CHIPS-Child is a parallel, ancillary study to the CHIPS randomized controlled trial (RCT). CHIPS is designed to determine whether 'less tight' control [target diastolic BP (dBP) 100mmHg] or 'tight' control [target dBP 85mmHg] of non-proteinuric hypertension in pregnancy is better for the baby without increasing maternal risk. CHIPS-Child will examine offspring of CHIPS participants non-invasively at 12m corrected post-gestational age (±2m) for anthropometry, hair cortisol, buccal swabs for epigenetic testing and a maternal questionnaire about infant feeding practices and background. Annual contact will be maintained in years 2-5 and will include annual parental measurement of the child's height, weight and waist circumference. CHIPS will recruit 1028 women. We estimate that 80% of CHIPS centres will participate in CHIPS-Child, approximately 97% of babies will survive, and 90% of children will be followed to 12m resulting in a sample size of 626. Power will be >80% to detect a between-group difference of ⩾0.25 in 'change in z-score for weight' between birth and 12m (2-sided alpha=0.05, SD 1).

RESULTS

Recruitment has begun. The primary outcome will be the between-group difference in early postnatal weight gain ('change in z score for weight') between birth and 12m (p<0.05). Secondary:outcomes are (i) hypothalamic pituitary adrenal axis function (hair cortisol for overall cortisol production); and (ii) between-groups differences in DNA methylation, using targeted (genes associated with growth, obesity, cardiovascular disease, and/or a developmental programming effect) and global (genome-wide microarray) methods.

CONCLUSION

CHIPS-Child offers a unique opportunity to both clarify whether differential dBP control in pregnancy has developmental programming effects and contribute to our understanding of human biology and diversity in a way that a cross-sectional or other observational studies cannot.

PP024. Random urine albumin: Creatinine ratio in high-risk pregnancy - Is it clinically useful?

INTRODUCTION

The albumin:creatinine ratio (ACr) is the newest of available methods of proteinuria assessment in pregnancy. Published cut-offs for detection of ⩾0.3g/d proteinuria vary from 2mg/mmol to 8mg/mmol. Up to 20% of women have an elevated ACr in pregnancy but normal outcome. In addition, it is our impression that the urine albumin component of the ACr is frequently below the detection limit of the assay.

OBJECTIVES

To evaluate the frequency with which a measurable ACr can be obtained in a high-risk outpatient maternity population.

METHODS

In this prospective cohort study, consecutive inpatients or outpatients (attending primarily morning high-risk maternity clinics) were evaluated at a tertiary care facility. Random midstream urine samples were obtained as part of normal clinical care. In the hospital laboratory, urinary albumin was measured using an immunoturbidimetric method, and urinary creatinine by an enzymatic method, both on an automated analyser (Vitros® 5,1 FS or Vitros® 5600, Ortho-Clinical Diagnostics, Rochester NY). ACr was calculated for samples with measurable urine albumin, and for samples with albumin below the assay range, ACr was calculated using the assay cut-off for albumin of 6.00mg/L.

RESULTS

One hundred and sixty women (81.9% outpatients) were screened at one/more antenatal visits, providing a total of 233 urine samples for analysis. 68 (29.2%) urine samples were dilute (i.e., had urinary creatinine <3mM); only 13 (19.1%) of these had measurable urinary albumin for calculation of the ACr. Overall, 117/233 samples (50.2%) had measurable urine albumin that could be used to calculate the ACr. 76 (65.0%) had ACr >2mg/mmol and 34 (29.1%) had ACr >8mg/mmol. For the 116/233 (49.8%) samples with urine albumin below the assay detection limit, ACr was calculated using 6.00mg/L as the value for urine albumin. All of the 55 dilute samples had an ACr >2mg/mmol and 3 (2.6%) had an ACr >8mg/mmol. If dilute samples were excluded, none of the remaining 61 samples had an ACr value >2mg/mmol.

CONCLUSION

Among a population of pregnant women attending primarily morning high-risk maternity clinics, urine is often dilute and urine albumin is often below the assay detection limit. This combination may result in uninterpretable ACr values if an ACr cut-off of 2mg/mmol is used as the decision limit for proteinuria ⩾0.3g/d. ACr may be best performed on first voided (concentrated) urine if ACr is used to assess proteinuria in pregnancy.

OS032. Pharmacotherapy for pre-eclampsia in low and middle income countries: An analysis of essential medicines lists (EMLS)

INTRODUCTION

Pre-eclampsia is the second leading cause of maternal mortality in low and middle income countries (LMIC). Pharmacological management of pre-eclampsia has five major components including antihypertensive therapy for severe and non-severe hypertension, magnesium sulphate for prevention or treatment of eclampsia, treatment of pre-eclampsia-related end-organ complications, antenatal corticosteroids for acceleration of fetal pulmonary maturity given iatrogenic preterm delivery for maternal and/or fetal indications, and labour induction for such indicated deliveries. Essential medicines are defined by the World Health Organization (WHO) as "drugs that satisfy the health care needs of the majority of the population". Essential Medicines Lists (EMLs) detail these essential medicines within an individual country and support the argument that the medication should be routinely available.

OBJECTIVES

To determine how many drugs required for comprehensive pre-eclampsia management are listed in national EMLs of LMIC.

METHODS

We conducted a descriptive analysis of relevant drug prevalence on identified EMLs. We searched for the national EMLs of the 144 LMIC identified by the World Bank. EMLs were collected by broad based internet searches and in collaboration with the WHO. The EMLs were surveyed for therapies for the different aspects of pre-eclampsia management: hypertension (non-severe and severe with oral or parenteral agents), eclampsia, pre-eclampsia complications (e.g., pulmonary oedema, thrombosis), preterm birth, and labour induction.

RESULTS

EMLs were located and reviewed for 58(40.3%) of LMIC. One or more parenteral antihypertensive agents were listed in 51(87.9%) EMLs. The most common agents were: hydralazine (67.2%), verapamil (58.6%), propranolol (39.7%) and sodium nitroprusside (37.9%); parenteral labetalol was listed by only 19.0% of EMLs. The most prevalent oral antihypertensive therapies listed were: nifedipine (96.6%, usually 10 or 20mg intermediate-acting tablets), methyldopa (94.8%), propranolol (89.7%), and atenolol (87.9%). Captopril, enalapril, hydrochlorothiazide and spironolactone were commonly listed. Magnesium sulphate for prevention and management of eclampsia was present in 86.2% of EMLs (and its antidote, calcium gluconate in 82.8%). To manage complications of pre-eclampsia, oral frusemide was listed in 94.8% of EMLs and parenteral heparin in 91.4%. Most EMLs listed parenteral dexamethasone (91.4%) for acceleration of fetal pulmonary maturity and oxytocin (98.3%) or a prostanoid (usually misoprostol, 39.7%) for labour induction.

CONCLUSION

EMLs of LMIC provide comprehensive coverage of all aspects of recommended pre-eclampsia pharmacotherapy. These EMLs may be used as advocacy tools to ensure the availability of these therapies within each country.

PP023. Unexpected random urinary protein: creatinine ratio results - Insightsfrom clinician-laboratory medicine collaboration

INTRODUCTION

Proteinuria assessment is important in pregnancy, particularly in determining whether or not a woman has pre-eclampsia. The random protein to creatinine ratio (PrCr) has been recommended as a confirmatory test for dipstick proteinuria in pregnancy, defined as random PrCr ⩾30mg/mmol. However, it has been our clinical impression that women with normal pregnancy outcomes have fluctuating or persistently elevated PrCr values.

OBJECTIVES

As the primary goal of proteinuria testing in pregnancy should be to identify women at increased risk of adverse outcomes, we sought to explore our clinical impression that an elevated PrCr is seen not infrequently in pregnancies with normal outcome.

METHODS

In this prospective cohort study, consecutive inpatients or outpatients (attending high-risk maternity clinics) were evaluated at a tertiary care facility. Random midstream urine samples were obtained as part of normal clinical care. Urine protein was measured using a pyrocatechol violet molybdate dye-binding method, and urine creatinine by an enzymatic method, both on an automated analyser (Vitros® 5.1 FS or Vitros® 5600, Ortho-Clinical Diagnostics, Rochester, NY) followed by PrCr calculation. Maternal and perinatal outcomes were abstracted from the hospital case notes.

RESULTS

160 women (81.9% outpatients) were screened at one/more antenatal visits providing a total of 233 samples for analysis. Ninety one (39.1%) samples had a random PrCr ⩾30 mg/mmol. This result was more common when urinary creatinine concentration was <3mM [64 (94.1%)] compared with ⩾3mM [27 (16.4%)], even among the 32 (20.0%) women with known normal pregnancy outcome [(13 (92.9%) vs. 0 (0%), respectively] (Panel A). In dilution studies using the same automated analyser, urinary protein (at a concentration of 0.12g/L) was 'detected' in deionised, double-distilled water. Method-specific re-analysis of data from two other published cohorts from our centre revealed substantially less inflation of PrCr values in dilute 24h urine samples tested using a pyrogallol red dye-binding based protein assay. When results were categorized according to urinary creatinine <3mM vs. ⩾3mM, PrCr ⩾30mg/mmol occurred in 12 (66.7%) vs. 99 (55.3%) respectively (p=0.35) in a 24-h urine completeness cohort and 92 (73.6%) vs. 313 (64.9%) respectively (p=0.07) in a cohort of women hospitalised for pre-eclampsia (Panel B).

CONCLUSION

Random urinary PrCr results may be inflated in dilute urines because of overestimation of proteinuria in a common pyrocatechol violet dye-based method. This inflation was reduced but not eliminated when the dye used was pyrogallol red. Analytical methods do matter in the assessment of proteinuria in pregnant women. It may be prudent to consider the potential for falsely positive PrCr ⩾30mg/mmol in dilute urine, and to order PrCr testing on first voided (concentrated) urines whenever possible.

Identifying potentially eligible subjects for research: paper-based logs versus the hospital administrative database

INTRODUCTION

The Canadian Perinatal Network (CPN) is a national database focused on threatened very pre-term birth. Women with one or more conditions most commonly associated with very pre-term birth are included if admitted to a participating tertiary perinatal unit at 22 weeks and 0 days to 28 weeks and 6 days.

METHODS

At BC Women's Hospital and Health Centre, we compared traditional paper-based ward logs and a search of the Canadian Institute for Health Information (CIHI) electronic database of inpatient discharges to identify patients.

RESULTS

The study identified 244 women potentially eligible for inclusion in the CPN admitted between April and December 2007. Of the 155 eligible women entered into the CPN database, each method identified a similar number of unique records (142 and 147) not ascertained by the other: 10 (6.4%) by CIHI search and 5 (3.2%) by ward log review. However, CIHI search achieved these results after reviewing fewer records (206 vs. 223) in less time (0.67 vs. 13.6 hours for ward logs).

CONCLUSION

Either method is appropriate for identification of potential research subjects using gestational age criteria. Although electronic methods are less time-consuming, they cannot be performed until after the patient is discharged and records and charts are reviewed. Each method's advantages and disadvantages will dictate use for a specific project.

Do Commonly Used Oral Antihypertensives Alter Fetal or Neonatal Heart Rate Characteristics? A Systematic Review

OBJECTIVE

To examine fetal (FHR) and neonatal heart rate patterns following use of common oral antihypertensives in pregnancy.

METHODS

A systematic review of randomized controlled trials (RCTs), observational studies (N >/= 6 women), and animal studies. Data were abstracted (two reviewers) to determine relative risk (RR) (or risk difference (RD) for low event rates) and 95% CI.

RESULTS

Eighteen RCTs (1858 women), one controlled observational study (N = 22), and seven case series (N = 117) were reviewed. Most hypertension was pregnancy-induced (N = 14 studies). The FHR was assessed by cardiotocogram (CTG) (N = 17 studies (visual interpretation); 1 study (computerized CTG), or umbilical artery velocimetry (N = 4). Four studies examined neonatal heart rate. In placebo-controlled RCTs (N = 192 women), adverse FHR effects did not differ between groups [9/101 (drugs) vs. 7/91 (placebo); RD 0.02, 95% CI (- 0.06, 0.11); chi2 = 1.02]. In six drug vs. drug RCTs (295 women), adverse FHR effects did not differ between groups [29/144 (methyldopa) vs. 42/151 (other drugs); RR 0.72, 95% CI (0.49, 1.07); chi2 = 0.69]. In one labetalol vs. placebo trial, neonatal bradycardia did not differ between groups [4/70 (labetalol) vs. 4/74 (placebo); OR 1.06, 95% CI (0.26, 4.39)], while in three drug vs. drug RCTs, neonatal bradycardia was not observed (0/24 vs. 0/26).

CONCLUSIONS

Available data are inadequate to conclude whether oral methyldopa, labetalol, nifedipine, or hydralazine adversely affect fetal or neonatal heart rate and pattern. Until definitive data are available, FHR changes cannot be reliably attributed to drug effect, but may be due to progression of the underlying maternal or placental disease.

What is SNOMED CT and why should the ISSHP care?

SNOMED CT (Systematized NOmenclature of MEDicine Clinical Terms) is a standardized multilingual healthcare terminology. It was developed to meet the needs of our electronic world so that care can be documented and clinicians can retrieve and transmit data in electronic format. It is anticipated that SNOMED CT will provide the core general terminology for electronic health records and, as such, replace existing classification systems such as the International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10). At present, there is no special interest group for the hypertensive disorders of pregnancy (HDP) within the SNOMED CT initiative. We believe that members of the ISSHP, and others interested in the HDP, should take a leadership role in this regard for a number of reasons.

Dalteparin for the prevention of recurrence of placental-mediated complications of pregnancy in women without thrombophilia: a pilot randomized controlled trial

BACKGROUND

The role of anticoagulants for the prevention of placental-mediated pregnancy complications is uncertain.

OBJECTIVES

Our aim was to investigate the effectiveness of dalteparin, a low-molecular-weight heparin, in preventing the recurrence of these complications in women without thrombophilia.

PATIENTS/METHODS

Between August 1 2000 and June 20 2007, 116 pregnant women with: (i)

RESULTS

Among the 110 women included in the final analysis, dalteparin was associated with a lower rate of the primary outcome [5.5% (n = 3/55) vs. 23.6% (n = 13/55), adjusted odds ratio (OR) 0.15, 95% confidence interval (CI) 0.03-0.70]. Secondary outcomes were not statistically different between the groups. Bleeding problems or thrombocytopenia did not occur.

CONCLUSION

In this pilot study, dalteparin is effective in decreasing the recurrence of placental-mediated complications in women without thrombophilia. Our results require confirmation in further randomized trials.

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Key Words Collapse

MESH Headings

• Adult
• Dalteparin/adverse effects
• Dalteparin/therapeutic use
• Female
• Fetal Death
• Humans
• Infant, Low Birth Weight
• Infant, Newborn
• Pilot Projects
• Placenta/physiopathology
• Pre-Eclampsia/prevention & control
• Pregnancy
• Pregnancy Complications/drug therapy
• Pregnancy Complications/prevention & control
• Pregnancy Outcome
• Secondary Prevention

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Grants Collapse

Affiliation(s)

E Rey Division of Obstetrics Medicine, Department of Obstetrics and Gynaecology, CHU Sainte-Justine, Montreal, QC, Canada.
P Garneau
M David
R Gauthier
L Leduc
N Michon
F Morin
C Demers
S R Kahn
L A Magee
M Rodger

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Pre-eclampsia and increased cardiovascular risk

Guidelines for primary prevention of cardiovascular disease are appropriate for all women

The Control of Hypertension In Pregnancy Study pilot trial

OBJECTIVE

To determine whether 'less tight' (versus 'tight') control of nonsevere hypertension results in a difference in diastolic blood pressure (dBP) between groups.

DESIGN

Randomised controlled trial (ISRCTN#57277508).

SETTING

Seventeen obstetric centres in Canada, Australia, New Zealand, and UK.

POPULATION

Inclusion: pregnant women, dBP 90-109 mmHg, pre-existing/gestational hypertension; live fetus(es); and 20-33(+6) weeks. Exclusion: systolic blood pressure > or = 170 mmHg and proteinuria, contraindication, or major fetal anomaly.

METHODS

Randomisation to less tight (target dBP, 100 mmHg) or tight (target dBP, 85 mmHg) blood pressure control.

MAIN OUTCOME MEASURES

Primary: mean dBP at 28, 32 and 36 weeks. Secondary: clinician compliance and women's satisfaction. Other: serious perinatal and maternal complications.

RESULTS

A total of 132 women were randomised to less tight (n = 66; seven had no study visit) or tight control (n= 66; one was lost to follow up; seven had no study visit). Mean dBP was significantly lower with tight control: -3.5 mmHg, 95% credible interval (-6.4, -0.6). Clinician compliance was 79% in both groups. Women were satisfied with their care. With less tight (versus tight) control, the rates of other treatments and outcomes were the following: post-randomisation antenatal antihypertensive medication use: 46 (69.7%) versus 58 (89.2%), severe hypertension: 38 (57.6%) versus 26 (40.0%), proteinuria: 16 (24.2%) versus 20 (30.8%), serious maternal complications: 3 (4.6%) versus 2 (3.1%), preterm birth: 24 (36.4%) versus 26 (40.0%), birthweight: 2675 +/- 858 versus 2501 +/- 855 g, neonatal intensive care unit (NICU) admission: 15 (22.7%) versus 22 (34.4%), and serious perinatal complications: 9 (13.6%) versus 14 (21.5%).

CONCLUSION

The CHIPS pilot trial confirms the feasibility and importance of a large definitive trial to determine the effects of less tight control on serious perinatal and maternal complications.

The complications of hypertension in pregnancy

The hypertensive disorders of pregnancy remain a leading cause of maternal and perinatal morbidity and mortality in Europe and North America. Pre-eclampsia, which is proteinuric gestational hypertension, accounts for the majority of the excess risks and is defined by the maternal syndrome. The maternal syndrome of pre-eclampsia is characterised by a systemic inflammatory response and its sequelae. Systematic multisystem evaluation of pre-eclampsia, evidence-based antihypertensive therapy, and the use of MgSO4 to prevent and treat the seizures of eclampsia can reduce maternal risks. For mild-to-moderate pregnancy hypertension, maternal risks are small, and there may be adverse perinatal consequences of blood pressure normalisation. Early-onset and severe pre-eclampsia predict an excess risk of later cardiovascular morbidity and mortality. Both Chlamydophila pneumoniae and cytomegalovirus have bee associated with pre-eclampsia and atherosclerosis, and may provide a mechanistic link between pre-eclampsia and the recognised cardiovascular risk. Women with a history of either early-onset and/or severe pre-eclampsia should be considered to be at increased risk for later cardiovascular disease, and it may be prudent for them to have regular lipid profiles and tests for urinary microalbumin excretion.

Excess syncytiotrophoblast microparticle shedding is a feature of early-onset pre-eclampsia, but not normotensive intrauterine growth restriction

RATIONALE

Syncytiotrophoblast microparticles (STBM) are shed into the maternal circulation in higher amounts in pre-eclampsia compared to normal pregnancy and are believed to be the stimulus for the systemic inflammatory response and endothelial cell damage which characterises the maternal syndrome. The excess shedding of STBM may be caused by hypoxia as a result of poor placentation, which is often a feature of pre-eclampsia. Similar placental pathology occurs in some cases of normotensive intrauterine growth restriction (nIUGR), but in the absence of maternal disease.

OBJECTIVE

To examine whether the shedding of STBM in nIUGR occurs to the same extent as in pre-eclampsia.

METHODS

A prospective case-control study in a tertiary referral centre of: 1) women with early-onset pre-eclampsia (EOPET < 34 week), 2) women with late-onset pre-eclampsia (LOPET > or = 34 week), 3) women with nIUGR), 4) matched normal pregnant women (NPC), and 5) non-pregnant women. An ELISA using the antitrophoblast antibody NDOG2 was used to measure STBM levels in peripheral venous plasma. Non-parametric analyses were conducted with statistical significance set at p < 0.05.

RESULTS

STBM levels rise during normal pregnancy. EOPET was associated with increased STBM levels (EOPET (median): 41 ng/ml, n = 15) compared with matched normal pregnancy (16 ng/ml, n = 15; Wilcoxon p = 0.005). LOPET (50 ng/ml, n = 10) and nIUGR (18 ng/ml, n = 8) STBM levels did not differ from matched normal pregnancy (36 ng/ml, n = 15, and 36 ng/ml, n = 8, respectively). Background levels in non-pregnant plasma were 0.49 ng/ml, n = 10.

CONCLUSIONS

Increased STBM levels were found in EOPET but not in nIUGR providing further evidence for their role in the pathogenesis of the maternal syndrome.

The safety of antihypertensives for treatment of pregnancy hypertension

This review addresses the maternal and perinatal benefits and risks of antihypertensive therapy in pregnancy. It covers the diagnosis of hypertension in pregnancy (with a brief discussion of ambulatory blood pressure measurement) followed by both the general principles of management of pregnancy hypertension and the specifics of individual antihypertensive drugs and drug classes. Discussion is focused on quantitative overviews of randomised, controlled trials, although observational literature is also discussed, particularly in reference to the potential teratogenicity of agents and the safety of their administration to nursing mothers. The treatment of severe hypertension is addressed separately from the treatment of mild-to-moderate hypertension, for which the maternal and fetal risks are substantially different.

Serious perinatal complications of non-proteinuric hypertension: an international, multicentre, retrospective cohort study

OBJECTIVE

To determine the proportion of births complicated by either a pre-existing or a gestational non-proteinuric hypertension, presenting at <34 weeks' gestation, and the associated incidence with 1 or more serious perinatal complications or birth weight <3rd centile for gestational age.

METHODS

A retrospective chart review was conducted in 5 international centres, from 1998 to 2002, where "tight" control (normalization) of blood pressure (BP) is the norm. International Classification of Diseases (ICD) codes were used to identify women who delivered at > or =20 weeks' gestation, with any hypertensive disorder of pregnancy. Women were included if they had a diastolic blood pressure (dBP) of 90 to 109 mm Hg, due to either a pre-existing or a gestational non-proteinuric hypertension, presenting at <34 weeks' gestation. Women were excluded if they had ongoing severe hypertension, or if at presentation with dBP of 90 to 109 mm Hg, they had 1 or more of the following: proteinuria, an indication for "tight" control of BP or imminent delivery, or a known intrauterine fetal death or lethal fetal anomaly. Data were collected on paper forms, scanned into an electronic database, and summarized descriptively by type of hypertension.

RESULTS

There were 305 eligible women (0.7% deliveries, 12.8% hypertensive deliveries) identified with non-proteinuric hypertension that was either pre-existing (133 [43.6%]) or gestational (172 [56.4%]). Regardless of hypertension type, 16.4% (n = 50) of pregnancies were complicated by birth weight <3rd centile or 1 or more serious perinatal complications, 34.3% (n = 100) by preterm birth, 30.8% (n = 94) by preeclampsia, and 2.0% (n = 6) by serious maternal complications.

CONCLUSION

Non-proteinuric pre-existing or gestational hypertension, presenting before 34 weeks' gestation, identifies a subpopulation of hypertensive pregnant women at both substantial perinatal risk and maternal risk. The CHIPS (Control of Hypertension In Pregnancy Study) trial is designed to determine how best to manage the hypertension of such women in order to optimize perinatal outcome.

Drugs in pregnancy. Antihypertensives

Fifty per cent of pregnancies are unplanned, and 1-6% of young women have pre-existing hypertension. However, no commonly used antihypertensive agent is known to be teratogenic. ACE inhibitors (and angiotensin-receptor antagonists) should be discontinued due to fetotoxicity. Five to 10% of pregnant women have hypertension, of which pre-existing hypertension is but one type. There is consensus that severe maternal hypertension (blood pressure >or=170/110 mmHg) should be treated to minimize the risk of acute cerebrovascular complications. Parenteral hydralazine may be associated with a higher risk of maternal hypotension, and intravenous labetalol with neonatal bradycardia. There is no consensus that mild-to-moderate hypertension in pregnancy should be treated. Clinical trials indicate that transient severe hypertension, antenatal hospitalization, proteinuria at delivery and neonatal respiratory distress syndrome may be decreased by normalizing blood pressure, but intrauterine fetal growth restriction may be increased. Methodological problems with published trials warrant cautious interpretation of these findings. Methyldopa and beta-blockers have been used most extensively, although atenolol may impair fetal growth in particular and should be avoided.

Treating hypertension in women of child-bearing age and during pregnancy

Hypertension is found among 1 to 6% of young women. Treatment aims to decrease cardiovascular risk, the magnitude of which is less dependent on the absolute level of blood pressure (BP) than on associated cardiovascular risk factors, hypertension-related target organ damage and/or concomitant disease. Lifestyle modifications are recommended for all hypertensive individuals. The threshold of BP at which antihypertensive therapy should be initiated is based on absolute cardiovascular risk. Most young women are at low risk and not in need of antihypertensive therapy. All antihypertensive agents appear to be equally efficacious; choice depends on personal preference, social circumstances and an agent's effect on cardiovascular risk factors, target organ damage and/or concomitant disease. Although most agents are appropriate for, and tolerated well by, young women, another consideration remains that of pregnancy, 50% of which are unplanned. A clinician must be aware of a woman's method of contraception and the potential of an antihypertensive agent to cause birth defects following inadvertent exposure in early pregnancy. Conversely, if an oral contraceptive is effective and well tolerated, but the woman's BP becomes mildly elevated, continuing the contraceptive and initiating antihypertensive treatment may not be contraindicated, especially if the ability to plan pregnancy is important (e.g. in type 1 diabetes mellitus). No commonly used antihypertensive is known to be teratogenic, although ACE inhibitors and angiotensin receptor antagonists should be discontinued, and any antihypertensive drugs should be continued in pregnancy only if anticipated benefits outweigh potential reproductive risk(s). The hypertensive disorders of pregnancy complicate 5 to 10% of pregnancies and are a leading cause of maternal and perinatal mortality and morbidity. Treatment aims to improve pregnancy outcome. There is consensus that severe maternal hypertension (systolic BP > or = 170mm Hg and/or diastolic BP > or = 110mm Hg) should be treated immediately to avoid maternal stroke, death and, possibly, eclampsia. Parenteral hydralazine may be associated with a higher risk of maternal hypotension, and intravenous labetalol with neonatal bradycardia. There is no consensus as to whether mild-to-moderate hypertension in pregnancy should be treated: the risks of transient severe hypertension, antenatal hospitalisation, proteinuria at delivery and neonatal respiratory distress syndrome may be decreased by therapy, but intrauterine fetal growth may also be impaired, particularly by atenolol. Methyldopa and other beta-blockers have been used most extensively. Reporting bias and the uncertainty of outcomes as defined warrant cautious interpretation of these findings and preclude treatment recommendations.

Factors associated with elective termination of pregnancy among Canadian and American women with nausea and vomiting of pregnancy

Case reports have associated severe nausea and vomiting of pregnancy (NVP) with elective termination of pregnancy. Therefore, our objective was to explore the determinants of consideration of termination and actual termination of pregnancy among women with NVP. From 1996 to 1997, callers to an advertised NVP Healthline underwent a semi-structured interview. From callers who retrospectively reported on NVP in a previous pregnancy, a nested unmatched case-control study was performed. Callers were divided into three groups: those who reported having electively terminated their pregnancy due to NVP, those who considered termination due to NVP and those who never considered termination. The severity of nausea and vomiting, and frequency of psychosocial morbidity, were compared between cases and controls, and multivariate logistic regression analysis was used to determine factors independently associated with termination and/or consideration of termination of pregnancy due to NVP. Of 3201 callers with NVP, 413 women reported having considered termination of pregnancy for NVP, 108 reported termination due to NVP and 2609 reported never having considered termination for NVP. The following factors were independently associated with a woman's consideration of termination of pregnancy due to NVP: unplanned pregnancy (p = 0.002), multiparity (p = 0.0001), more severe vomiting (p = 0.003), feelings of depression (p < 0.0001) and reported adverse effects of NVP on both her partner's daily life (p = 0.04) and her relationship with her partner (p = 0.0003). The following factors were independently associated with actual termination of pregnancy due to NVP: unplanned pregnancy (p < 0.0001), multiparity (p = 0.03) and feelings of depression (p = 0.001). There were no significant interactions between factors. Consideration of termination, or actual termination of pregnancy, due to NVP are associated with psychosocial circumstances, which should be taken into consideration when managing these women.

Critical appraisal of drug therapy for nausea and vomiting of pregnancy: II. Efficacy and safety of diclectin (doxylamine-B6)

Nausea and vomiting of pregnancy is the most common condition in pregnancy and affects up to 80% of all pregnant women. There are a large number of pharmacological agents that are effective for the treatment of nausea and vomiting associated with conditions such as motion sickness and gastrointestinal conditions; however, their use in pregnancy is limited by the lack of sufficient data on their potential teratogenic effects. The efficacy of the delayed-release combination of doxylamine and pyridoxine (Bendectin, Diclectin) has been shown in several randomized, controlled trials. The present review aims to refute the unsubstantiated beliefs that Diclectin is unsafe when used in the treatment of nausea and vomiting of pregnancy.

The generalizability of trial data; a comparison of beta-blocker trial participants with a prospective cohort of women taking beta-blockers in pregnancy

OBJECTIVE

To evaluate the generalizability of randomized controlled trial (RCT) data to obstetric practice, using the example of beta-blocker therapy.

STUDY DESIGN

Descriptive comparison of characteristics of participants, interventions, and outcomes assessed between a meta-analysis of trials of beta-blocker therapy in pregnancy, and a prospective cohort of beta-blocker exposed callers to Motherisk, a Teratology Information Service.

RESULTS

72 women (cohort) and 34 trials with 2474 participants (meta-analysis) were compared. The generalizability of trials was limited by an inadequate description of maternal demographics and indications for beta-blockers, and a focus on the effectiveness of beta-blockers as antihypertensives rather than on reproductive risks.

CONCLUSIONS

Some of these limitations could be rectified. Others cannot, such as evaluation of teratogenicity (for ethical reasons) or all indications for a drug (for practical reasons). Reference to observational literature is, and will likely remain, necessary to address the 'harm' side of the therapeutic equation in pregnancy.