Association between perinatal mortality and morbidity and customised and non-customised birthweight centiles in Denmark, Finland, Norway, Wales, and England: comparative, population based, record linkage study

Objectives

To compare the risk of adverse perinatal outcomes according to infants who are born small for gestational age (SGA; <10th centile) or large for gestational age (LGA; >90th centile), as defined by birthweight centiles that are non-customised (ie, standardised by sex and gestational age only) and customised (by sex, gestational age, maternal weight, height, parity, and ethnic group).

Design

Comparative, population based, record linkage study with meta-analysis of results.

Setting

Denmark, Finland, Norway, Wales, and England (city of Bradford), 1986-2019.

Participants

2 129 782 infants born at term in birth registries.

Main outcome measures

Stillbirth, neonatal death, infant death, admission to neonatal intensive care unit, and low Apgar score (<7) at 5 minutes.

Results

Relative to those infants born average for gestational age (AGA), both SGA and LGA births were at increased risk of all five outcomes, but observed relative risks were similar irrespective of whether non-customised or customised charts were used. For example, for SGA versus AGA births, when non-customised and customised charts were used, relative risks pooled over countries were 3.60 (95% confidence interval 3.29 to 3.93) versus 3.58 (3.02 to 4.24) for stillbirth, 2.83 (2.18 to 3.67) versus 3.32 (2.05 to 5.36) for neonatal death, 2.82 (2.07 to 3.83) versus 3.17 (2.20 to 4.56) for infant death, 1.66 (1.49 to 1.86) versus 1.54 (1.30 to 1.81) for low Apgar score at 5 minutes, and (based on Bradford data only) 1.97 (1.74 to 2.22) versus 1.94 (1.70 to 2.21) for admission to the neonatal intensive care unit. The estimated sensitivity of combined SGA or LGA births to identify the three mortality outcomes ranged from 31% to 34% for non-customised charts and from 34% to 38% for customised charts, with a specificity of 82% and 80% with non-customised and customised charts, respectively.

Conclusions

These results suggest an increased risk of adverse perinatal outcomes of a similar magnitude among SGA or LGA term infants when customised and non-customised centiles are used. Use of customised charts for SGA/LGA births-over and above use of non-customised charts for SGA/LGA births-is unlikely to provide benefits in terms of identifying term births at risk of these outcomes.

A national cohort study and confidential enquiry to investigate ethnic disparities in maternal mortality

BACKGROUND

Ethnic disparities in maternal mortality were first documented in the UK in the early 2000s but are known to be widening. This project aimed to describe the women who died in the UK during or up to a year after the end of pregnancy, to compare the quality of care received by women from different aggregated ethnic groups, and to identify any structural or cultural biases or discrimination affecting their care.

METHODS

National surveillance data was used to identify all 1894 women who died during or up to a year after the end of pregnancy between 2009 and 18 in the UK. Their characteristics and causes of death were described. A Confidential Enquiry was undertaken to describe the quality of care women received. The care of a stratified random sample of 54 women who died during or up to a year after the end of pregnancy between 2009 and 18, (18 from the aggregated group of Black women, 19 from the Asian aggregated group and 17 from the White aggregated group) was re-examined specifically to describe any structural or cultural biases or discrimination identified.

FINDINGS

There were no major differences causes of death between women from different aggregated ethnic groups, with cardiovascular disease the leading cause of death in all groups. Multiple areas of bias were identified in the care women received, including lack of nuanced care (notable amongst women from Black aggregated ethnic groups who died), microaggressions (most prominent in the care of women from Asian aggregated ethnic groups who died) and clinical, social and cultural complexity (evident across all ethnic groups).

INTERPRETATION

This confidential enquiry suggests that multiple structural and other biases exist in UK maternity care. Further research on the role of microaggressions is warranted.

FUNDING

This research is funded by the National Institute for Health Research (NIHR) Policy Research Programme, conducted through the Policy Research Unit in Maternal and Neonatal Health and Care, PR-PRU-1217-21,202. MK is an NIHR Senior Investigator. SK is part funded and FCS fully funded by the National Institute for Health Research (NIHR) Applied Research Centre (ARC) West Midlands. The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.

Ondansetron and metoclopramide as second-line antiemetics in women with nausea and vomiting in pregnancy: the EMPOWER pilot factorial RCT

BACKGROUND

Around one-third of pregnant women suffer from moderate to severe nausea and vomiting, causing physical and emotional distress and reducing their quality of life. There is no cure for nausea and vomiting in pregnancy. Management focuses on relieving symptoms and preventing morbidity, and often requires antiemetic therapy. National guidelines make recommendations about first-, second- and third-line antiemetic therapies, although care varies in different hospitals and women report feeling unsupported, dissatisfied and depressed.

OBJECTIVES

To determine whether or not, in addition to intravenous rehydration, ondansetron compared with no ondansetron and metoclopramide compared with no metoclopramide reduced the rate of treatment failure up to 10 days after drug initiation; improved symptom severity at 2, 5 and 10 days after drug initiation; improved quality of life at 10 days after drug initiation; and had an acceptable side effect and safety profile. To estimate the incremental cost per treatment failure avoided and the net monetary benefits from the perspectives of the NHS and women.

DESIGN

This was a multicentre, double-dummy, randomised, double-blinded, dummy-controlled 2 × 2 factorial trial (with an internal pilot phase), with qualitative and health economic evaluations.

PARTICIPANTS

Thirty-three patients (who were < 17 weeks pregnant and who attended hospital with nausea and vomiting after little or no improvement with first-line antiemetic medication) who attended 12 secondary care NHS trusts in England, 22 health-care professionals and 21 women participated in the qualitative evaluation.

INTERVENTIONS

Participants were randomly allocated to one of four treatment groups (1 : 1 : 1: 1 ratio): (1) metoclopramide and dummy ondansetron; (2) ondansetron and dummy metoclopramide; (3) metoclopramide and ondansetron; or (4) double dummy. Trial medication was initially given intravenously and then continued orally once women were able to tolerate oral fluids for a maximum of 10 days of treatment.

MAIN OUTCOME MEASURES

The primary end point was the number of participants who experienced treatment failure, which was defined as the need for further treatment because symptoms had worsened between 12 hours and 10 days post treatment. The main economic outcomes were incremental cost per additional successful treatment and incremental net benefit.

RESULTS

Of the 592 patients screened, 122 were considered eligible and 33 were recruited into the internal pilot (metoclopramide and dummy ondansetron, n = 8; ondansetron and dummy metoclopramide, n = 8; metoclopramide and ondansetron, n = 8; double dummy, n = 9). Owing to slow recruitment, the trial did not progress beyond the pilot. Fifteen out of 30 evaluable participants experienced treatment failure. No statistical analyses were performed. The main reason for ineligibility was prior treatment with trial drugs, reflecting an unpredicted change in prescribing practice at several points along the care pathway. The qualitative evaluation identified the requirements of the study protocol, in relation to guidelines on anti-sickness drugs, and the diversity of pathways to care as key hurdles to recruitment while the role of research staff was a key enabler. No important adverse events or side effects were reported.

LIMITATIONS

The pilot trial failed to achieve the recruitment target owing to unforeseen changes in the provision of care.

CONCLUSIONS

The trial was unable to provide evidence to support clinician decisions about the best choice of second-line antiemetic for nausea and vomiting in pregnancy.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN16924692 and EudraCT 2017-001651-31.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 63. See the NIHR Journals Library website for further project information.

Placental growth factor measurements in the assessment of women with suspected Preeclampsia: A stratified analysis of the PARROT trial

OBJECTIVE

Placental growth factor testing decreases time to recognition of preeclampsia and may reduce severe maternal adverse outcomes. This analysis aims to describe the clinical phenotype of women by PlGF concentration, and to determine the mechanism(s) underpinning the reduction in severe maternal adverse outcomes in the PARROT trial, in order to inform how PlGF testing may be optimally used within clinical management algorithms.

STUDY DESIGN

This was a planned secondary analysis from the PARROT trial that compared revealed PlGF testing and management guidance with usual care in the assessment of women with suspected preterm preeclampsia.

MAIN OUTCOME MEASURES

Maternal and perinatal outcomes following stratification of women by trial group, and measured PlGF concentration.

RESULTS

1006 women were included. PlGF < 100 pg/ml identified women with more marked hypertension, increased adverse maternal outcomes and preterm delivery rates, and higher rates of small for gestational age infants. There was a reduction in adverse maternal outcomes in women whose results were revealed when PlGF levels were 12-100 pg/ml compared to usual care (3.8% vs 6.9%; aOR 0.15(95% CI 0.03-0.92). There was no significant difference in gestation at delivery between concealed or revealed groups in any PlGF categories.

CONCLUSION

Low PlGF concentrations are associated with severe preeclampsia. The reduction in severe adverse maternal outcomes may be mediated through quicker diagnosis and intensive surveillance, as recommended by the management algorithm for those at increased risk. PlGF is particularly beneficial in those who test 12-100 pg/ml, as these may be women with silent multi-organ disease who otherwise may go undetected.

A national population-based cohort study to investigate inequalities in maternal mortality in the United Kingdom, 2009-17

BACKGROUND

Disparities have been documented in maternal mortality rates between women from different ethnic, age and socio-economic groups in the UK. It is unclear whether there are differential changes in these rates amongst women from different groups over time. The objectives of this analysis were to describe UK maternal mortality rates in different age, ethnic and socio-economic groups between 2009 and 2017, and to identify whether there were changes in the observed inequalities, or different trends amongst population subgroups.

METHODS

Maternal mortality rates with 95% confidence intervals (CI) in specific age, deprivation and ethnic groups were calculated using numbers of maternal deaths as numerator and total maternities as denominator. Relative risks (RR) with 95% CI were calculated and compared using ratios of relative risk. Change over time was investigated using non-parametric tests for trend across ordered groups.

RESULTS

Women from black and Asian groups had a higher mortality rate than white women in most time periods, as did women aged 35 and over and women from the most deprived quintile areas of residence. There was evidence of an increasing trend in maternal mortality amongst black women and a decrease in mortality amongst women from the least deprived areas, but no trends over time in any of the other ethnic, age or IMD groups were seen. There was a widening of the disparity between black and white women (RR 2.59 in 2009-11 compared with 5.27 in 2015-17, ratio of the relative risks 2.03, 95% CI 1.11, 3.72).

CONCLUSIONS

The clear differences in the patterns of maternal mortality amongst different ethnic, age and socio-economic groups emphasise the importance of research and policies focussed specifically on women from black and minority ethnic groups, together with other disadvantaged groups, to begin to reduce maternal mortality in the UK.

An evaluation of the influence of the publication of the UK National Institute for health and Care Excellence's guidance on hypertension in pregnancy: a retrospective analysis of clinical practice

Background

The UK National Institute for health and Care Excellence (NICE) publish guidance aimed at standardising practice. Evidence regarding how well recommendations are implemented and what clinicians think about guidance is limited. We aimed to establish the extent to which the NICE Hypertension in pregnancy (HIP) guidance has influenced care and assess clinician’s attitudes to this guidance.

Methods

Five maternity units in the Midlands and North of England took part in the retrospective evaluation of 2490 birth records from randomly selected dates in 2008–2010 and 2013–2015. The proportion of women where care was adhered to before (2008–2010) and after (2013–2015) guidance publication was examined and differences estimated. Eleven midwives and obstetricians employed by Bradford Hospitals were interviewed.

Results

The proportion of high risk women prescribed Aspirin rose (before 14%, after 54%, p = < 0.01 (confidence interval of change (CI) 37, 43%) as well as for moderate risk women (before 3%, after 54%, p = < 0.01, CI 48, 54%) following guidance publication. Three quarters had blood pressure and a third proteinuria measured at every antenatal visit before and after guidance. Early birth < 37 weeks and ≥ 37 weeks gestation was more frequently offered after guidance publication than before (< 37 weeks: before 9%, after 18%, p = 0.01, CI 2, 16% and ≥ 37 weeks before 30%, after 52%, p = < 0.01, CI 9, 35%). Few were informed of future risk of developing a hypertensive disorder or had a documented postnatal review; however there was an increase in women advised to see their GP for this review (58% before and 90% after guidance p = < 0.01, CI 24, 39%).

All clinicians said the NICE HIP guidance was informative and provided robust evidence, however they said length of the document made use in practice challenging. They did not always access NICE guidance, preferring to use local guidance at least initially; both obstetricians and midwives said they accessed NICE guidance for in-depth information.

Conclusions

NICE HIP guidance is valued, used by clinicians and has influenced important aspects of care that may help improve outcomes for women who develop hypertension or pre-eclampsia, however some recommendations have had limited impact and therefore interventions are required to improve adherence.

Risk factors, management, and outcomes of amniotic fluid embolism: A multicountry, population-based cohort and nested case-control study

BACKGROUND

Amniotic fluid embolism (AFE) remains one of the principal reported causes of direct maternal mortality in high-income countries. However, obtaining robust information about the condition is challenging because of its rarity and its difficulty to diagnose. This study aimed to pool data from multiple countries in order to describe risk factors, management, and outcomes of AFE and to explore the impact on the findings of considering United Kingdom, international, and United States AFE case definitions.

METHODS AND FINDINGS

A population-based cohort and nested case-control study was conducted using the International Network of Obstetric Survey Systems (INOSS). Secondary data on women with AFE (n = 99-218, depending on case definition) collected prospectively in population-based studies conducted in Australia, France, the Netherlands, Slovakia, and the UK were pooled along with secondary data on a sample of control women (n = 4,938) collected in Australia and the UK. Risk factors for AFE were investigated by comparing the women with AFE in Australia and the UK with the control women identified in these countries using logistic regression. Factors associated with poor maternal outcomes (fatality and composite of fatality or permanent neurological injury) amongst women with AFE from each of the countries were investigated using logistic regression or Wilcoxon rank-sum test. The estimated incidence of AFE ranged from 0.8-1.8 per 100,000 maternities, and the proportion of women with AFE who died or had permanent neurological injury ranged from 30%-41%, depending on the case definition. However, applying different case definitions did not materially alter findings regarding risk factors for AFE and factors associated with poor maternal outcomes amongst women with AFE. Using the most liberal case definition (UK) and adjusting for the severity of presentation when appropriate, women who died were more likely than those who survived to present with cardiac arrest (89% versus 40%, adjusted odds ratio [aOR] 10.58, 95% confidence interval [CI] 3.93-28.48, p < 0.001) and less likely to have a source of concentrated fibrinogen (40% versus 56%, aOR 0.44, 95% CI 0.21-0.92, p = 0.029) or platelets given (24% versus 49%, aOR 0.23, 95% CI 0.10-0.52, p < 0.001). They also had a lower dose of tranexamic acid (median dose 0.7 g versus 2 g, p = 0.035) and were less likely to have had an obstetrician and/or anaesthetist present at the time of the AFE (61% versus 75%, aOR 0.38, 95% CI 0.16-0.90, p = 0.027). Limitations of the study include limited statistical power to examine factors associated with poor maternal outcome and the potential for residual confounding or confounding by indication.

CONCLUSIONS

The findings of our study suggest that when an AFE is suspected, initial supportive obstetric care is important, but having an obstetrician and/or anaesthetist present at the time of the AFE event and use of interventions to correct coagulopathy, including the administration of an adequate dose of tranexamic acid, may be important to improve maternal outcome. Future research should focus on early detection of the coagulation deficiencies seen in AFE alongside the role of tranexamic acid and other coagulopathy management strategies.

Intravenous co-amoxiclav to prevent infection after operative vaginal delivery: the ANODE RCT

BACKGROUND

Sepsis is a leading cause of direct and indirect maternal death in both the UK and globally. All forms of operative delivery are associated with an increased risk of sepsis, and the National Institute for Health and Care Excellence's guidance recommends the use of prophylactic antibiotics at all caesarean deliveries, based on substantial randomised controlled trial evidence of clinical effectiveness. A Cochrane review, updated in 2017 (Liabsuetrakul T, Choobun T, Peeyananjarassri K, Islam QM. Antibiotic prophylaxis for operative vaginal delivery. Cochrane Database Syst Rev 2017;8:CD004455), identified only one small previous trial of prophylactic antibiotics following operative vaginal birth (forceps or ventouse/vacuum extraction) and, given the small study size and extreme result, suggested that further robust evidence is needed.

OBJECTIVES

To investigate whether or not a single dose of prophylactic antibiotic following operative vaginal birth is clinically effective for preventing confirmed or presumed maternal infection, and to investigate the associated impact on health-care costs.

DESIGN

A multicentre, randomised, blinded, placebo-controlled trial.

SETTING

Twenty-seven maternity units in the UK.

PARTICIPANTS

Women who had an operative vaginal birth at ≥ 36 weeks' gestation, who were not known to be allergic to penicillin or constituents of co-amoxiclav and who had no indication for ongoing antibiotics.

INTERVENTIONS

A single dose of intravenous co-amoxiclav (1 g of amoxicillin/200 mg of clavulanic acid) or placebo (sterile saline) allocated through sealed, sequentially numbered, indistinguishable packs.

MAIN OUTCOME MEASURES

Primary outcome - confirmed or suspected infection within 6 weeks of giving birth. Secondary outcomes - severe sepsis, perineal wound infection, perineal pain, use of pain relief, hospital bed stay, hospital/general practitioner visits, need for additional perineal care, dyspareunia, ability to sit comfortably to feed the baby, maternal general health, breastfeeding, wound breakdown, occurrence of anaphylaxis and health-care costs.

RESULTS

Between March 2016 and June 2018, 3427 women were randomised: 1719 to the antibiotic arm and 1708 to the placebo arm. Seven women withdrew, leaving 1715 women in the antibiotic arm and 1705 in the placebo arm for analysis. Primary outcome data were available for 3225 out of 3420 women (94.3%). Women randomised to the antibiotic arm were significantly less likely to have confirmed or suspected infection within 6 weeks of giving birth (180/1619, 11%) than women randomised to the placebo arm (306/1606, 19%) (relative risk 0.58, 95% confidence interval 0.49 to 0.69). Three serious adverse events were reported: one in the placebo arm and two in the antibiotic arm (one was thought to be causally related to the intervention).

LIMITATIONS

The follow-up rate achieved for most secondary outcomes was 76%.

CONCLUSIONS

This trial has shown clear evidence of benefit of a single intravenous dose of prophylactic co-amoxiclav after operative vaginal birth. These results may lead to reconsideration of official policy/guidance. Further analysis of the mechanism of action of this single dose of antibiotic is needed to investigate whether earlier, pre-delivery or repeated administration could be more effective. Until these analyses are completed, there is no indication for administration of more than a single dose of prophylactic antibiotic, or for pre-delivery administration.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN11166984.

FUNDING

This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 54. See the National Institute for Health Research Journals Library website for further project information.

Blood pressure change across pregnancy in white British and Pakistani women: analysis of data from the Born in Bradford cohort

The incidence of gestational hypertension (GH) and pre-eclampsia (PE) is increasing. Use of blood pressure (BP) change patterns may improve early detection of BP abnormalities. We used Linear spline random-effects models to estimate BP patterns across pregnancy for white British and Pakistani women. Pakistani women compared to white British women had lower BP during the first two trimesters of pregnancy, irrespective of the development of GH or PE or presence of a risk factor. Pakistani compared to white British women with GH and PE showed steeper BP increases towards the end of pregnancy. Pakistani women were half as likely to develop GH, but as likely to develop PE than white British women. To conclude; BP trajectories differ by ethnicity. Because GH developed evenly from 20 weeks gestation, and PE occurred more commonly after 36 weeks in both ethnic groups, the lower BP up to the third trimester in Pakistani women resulted in a lower GH rate, whereas PE rates, influenced by the steep third trimester BP increase were similar. Criteria for diagnosing GH and PE may benefit from considering ethnic differences in BP change across pregnancy.

Prophylactic antibiotics in the prevention of infection after operative vaginal delivery (ANODE): a multicentre randomised controlled trial

BACKGROUND

Risk factors for maternal infection are clearly recognised, including caesarean section and operative vaginal birth. Antibiotic prophylaxis at caesarean section is widely recommended because there is clear systematic review evidence that it reduces incidence of maternal infection. Current WHO guidelines do not recommend routine antibiotic prophylaxis for women undergoing operative vaginal birth because of insufficient evidence of effectiveness. We aimed to investigate whether antibiotic prophylaxis prevented maternal infection after operative vaginal birth.

METHODS

In a blinded, randomised controlled trial done at 27 UK obstetric units, women (aged ≥16 years) were allocated to receive a single dose of intravenous amoxicillin and clavulanic acid or placebo (saline) following operative vaginal birth at 36 weeks gestation or later. The primary outcome was confirmed or suspected maternal infection within 6 weeks of delivery defined by a new prescription of antibiotics for specific indications, confirmed systemic infection on culture, or endometritis. We did an intention-to-treat analysis. This trial is registered with ISRCTN, number 11166984, and is closed to accrual.

FINDINGS

Between March 13, 2016, and June 13, 2018, 3427 women were randomly assigned to treatment: 1719 to amoxicillin and clavulanic acid, and 1708 to placebo. Seven women withdrew, leaving 1715 in the amoxicillin and clavulanic acid group and 1705 in the placebo groups. Primary outcome data were missing for 195 (6%) women. Significantly fewer women allocated to amoxicillin and clavulanic acid had a confirmed or suspected infection (180 [11%] of 1619) than women allocated to placebo (306 [19%] of 1606; risk ratio 0·58, 95% CI 0·49-0·69; p<0·0001). One woman in the placebo group reported a skin rash and two women in the amoxicillin and clavulanic acid reported other allergic reactions, one of which was reported as a serious adverse event. Two other serious adverse events were reported, neither was considered causally related to the treatment.

INTERPRETATION

This trial shows benefit of a single dose of prophylactic antibiotic after operative vaginal birth and guidance from WHO and other national organisations should be changed to reflect this.

FUNDING

NIHR Health Technology Assessment programme.

Gestational diabetes and ultrasound-assessed fetal growth in South Asian and White European women: findings from a prospective pregnancy cohort

BACKGROUND

Maternal gestational diabetes (GDM) is an established risk factor for large size at birth, but its influence on intrauterine fetal growth in different ethnic populations is less well understood. Here, we examine the joint associations of GDM and ethnicity with longitudinal fetal growth in South Asian and White European origin women.

METHODS

This study included 10,705 singletons (4747 White European and 5958 South Asian) from a prospective cohort of women attending an antenatal clinic in Bradford, in the North of England. All women completed a 75-g oral glucose tolerance test at 26-28 weeks' gestation. Ultrasound measurements of fetal head circumference (HC), femur length (FL) abdominal circumference (AC), and estimated fetal weight (EFW), and corresponding anthropometric measurements at birth were used to derive fetal growth trajectories. Associations of GDM and ethnicity with these trajectories were assessed using multilevel fractional polynomial models.

RESULTS

Eight hundred thirty-two pregnancies (7.8%) were affected by GDM: 10.4% of South Asians and 4.4% of White Europeans. GDM was associated with a smaller fetal size in early pregnancy [differences (95% CI) in mean HC at 12 weeks and mean AC and EFW at 16 weeks comparing fetuses exposed to GDM to fetuses unexposed (reference) = - 1.8 mm (- 2.6; - 1.0), - 1.7 mm (- 2.5; - 0.9), and - 6 g (- 10; - 2)] and a greater fetal size from 24 weeks' gestation through to term [differences (95% CI) in mean HC, AC, and EFW comparing fetuses exposed to GDM to those unexposed = 0.9 mm (0.3; 1.4), 0.9 mm (0.2; 1.7), and 7 g (0; 13) at 24 weeks]. Associations of GDM with fetal growth were of similar magnitude in both ethnic groups. Growth trajectories, however, differed by ethnicity with South Asians being smaller than White Europeans irrespective of GDM status. Consequently, South Asian fetuses exposed to GDM were smaller across gestation than fetuses of White Europeans without GDM.

CONCLUSIONS

In both ethnic groups, GDM is associated with early fetal size deviations prior to GDM diagnosis, highlighting the need for novel strategies to diagnose pregnancy hyperglycemia earlier than current methods. Our findings also suggest that ethnic-specific fetal growth criteria are important in identifying hyperglycemia-associated pathological effects.

The identification and treatment of women with hyperglycaemia in pregnancy: an analysis of individual participant data, systematic reviews, meta-analyses and an economic evaluation

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with a higher risk of important adverse outcomes. Practice varies and the best strategy for identifying and treating GDM is unclear.

AIM

To estimate the clinical effectiveness and cost-effectiveness of strategies for identifying and treating women with GDM.

METHODS

We analysed individual participant data (IPD) from birth cohorts and conducted systematic reviews to estimate the association of maternal glucose levels with adverse perinatal outcomes; GDM prevalence; maternal characteristics/risk factors for GDM; and the effectiveness and costs of treatments. The cost-effectiveness of various strategies was estimated using a decision tree model, along with a value of information analysis to assess where future research might be worthwhile. Detailed systematic searches of MEDLINE^® and MEDLINE In-Process & Other Non-Indexed Citations^®, EMBASE, Cumulative Index to Nursing and Allied Health Literature Plus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Health Technology Assessment database, NHS Economic Evaluation Database, Maternity and Infant Care database and the Cochrane Methodology Register were undertaken from inception up to October 2014.

RESULTS

We identified 58 studies examining maternal glucose levels and outcome associations. Analyses using IPD alone and the systematic review demonstrated continuous linear associations of fasting and post-load glucose levels with adverse perinatal outcomes, with no clear threshold below which there is no increased risk. Using IPD, we estimated glucose thresholds to identify infants at high risk of being born large for gestational age or with high adiposity; for South Asian (SA) women these thresholds were fasting and post-load glucose levels of 5.2 mmol/l and 7.2 mmol/l, respectively and for white British (WB) women they were 5.4 and 7.5 mmol/l, respectively. Prevalence using IPD and published data varied from 1.2% to 24.2% (depending on criteria and population) and was consistently two to three times higher in SA women than in WB women. Lowering thresholds to identify GDM, particularly in women of SA origin, identifies more women at risk, but increases costs. Maternal characteristics did not accurately identify women with GDM; there was limited evidence that in some populations risk factors may be useful for identifying low-risk women. Dietary modification additional to routine care reduced the risk of most adverse perinatal outcomes. Metformin (Glucophage,^® Teva UK Ltd, Eastbourne, UK) and insulin were more effective than glibenclamide (Aurobindo Pharma - Milpharm Ltd, South Ruislip, Middlesex, UK). For all strategies to identify and treat GDM, the costs exceeded the health benefits. A policy of no screening/testing or treatment offered the maximum expected net monetary benefit (NMB) of £1184 at a cost-effectiveness threshold of £20,000 per quality-adjusted life-year (QALY). The NMB for the three best-performing strategies in each category (screen only, then treat; screen, test, then treat; and test all, then treat) ranged between -£1197 and -£1210. Further research to reduce uncertainty around potential longer-term benefits for the mothers and offspring, find ways of improving the accuracy of identifying women with GDM, and reduce costs of identification and treatment would be worthwhile.

LIMITATIONS

We did not have access to IPD from populations in the UK outside of England. Few observational studies reported longer-term associations, and treatment trials have generally reported only perinatal outcomes.

CONCLUSIONS

Using the national standard cost-effectiveness threshold of £20,000 per QALY it is not cost-effective to routinely identify pregnant women for treatment of hyperglycaemia. Further research to provide evidence on longer-term outcomes, and more cost-effective ways to detect and treat GDM, would be valuable.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013004608.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Ethnic differences in the clustering and outcomes of health behaviours during pregnancy: results from the Born in Bradford cohort

Background

Pregnancy is a time of optimal motivation for many women to make positive behavioural changes. We aim to describe pregnant women with similar patterns of self-reported health behaviours and examine associations with birth outcomes.

Methods

We examined the clustering of multiple health behaviours during pregnancy in the Born in Bradford cohort, including smoking physical inactivity, vitamin d supplementation and exposure to second-hand smoke. Latent class analysis was used to identify groups of individuals with similar patterns of health behaviours separately for White British (WB) and Pakistani mothers. Multinomial regression was then used to examine the association between group membership and birth outcomes, which included preterm birth and mean birthweight.

Results

For WB mothers, offspring of those in the 'Unhealthiest' group had lower mean birthweight than those in the 'Mostly healthy but inactive' class, although no association was observed for preterm birth. For Pakistani mothers, group membership was not associated with birthweight differences, although the odds of preterm birth was higher in 'Inactive smokers' compared to the 'Mostly healthy but inactive' group.

Conclusions

The use of latent class methods provides important information about the clustering of health behaviours which can be used to target population segments requiring behaviour change interventions considering multiple risk factors. Given the dominant negative association of smoking with the birth outcomes investigated, latent class groupings of other health behaviours may not confer additional risk information for these outcomes.

Treatments for gestational diabetes: a systematic review and meta-analysis

OBJECTIVE

To investigate the effectiveness of different treatments for gestational diabetes mellitus (GDM).

DESIGN

Systematic review, meta-analysis and network meta-analysis.

METHODS

Data sources were searched up to July 2016 and included MEDLINE and Embase. Randomised trials comparing treatments for GDM (packages of care (dietary and lifestyle interventions with pharmacological treatments as required), insulin, metformin, glibenclamide (glyburide)) were selected by two authors and double checked for accuracy. Outcomes included large for gestational age, shoulder dystocia, neonatal hypoglycaemia, caesarean section and pre-eclampsia. We pooled data using random-effects meta-analyses and used Bayesian network meta-analysis to compare pharmacological treatments (ie, including treatments not directly compared within a trial).

RESULTS

Forty-two trials were included, the reporting of which was generally poor with unclear or high risk of bias. Packages of care varied in their composition and reduced the risk of most adverse perinatal outcomes compared with routine care (eg, large for gestational age: relative risk0.58 (95% CI 0.49 to 0.68; I2=0%; trials 8; participants 3462). Network meta-analyses suggest that metformin had the highest probability of being the most effective treatment in reducing the risk of most outcomes compared with insulin or glibenclamide.

CONCLUSIONS

Evidence shows that packages of care are effective in reducing the risk of most adverse perinatal outcomes. However, trials often include few women, are poorly reported with unclear or high risk of bias and report few outcomes. The contribution of each treatment within the packages of care remains unclear. Large well-designed and well-conducted trials are urgently needed.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42013004608.

Risk factor screening to identify women requiring oral glucose tolerance testing to diagnose gestational diabetes: A systematic review and meta-analysis and analysis of two pregnancy cohorts

BACKGROUND

Easily identifiable risk factors including: obesity and ethnicity at high risk of diabetes are commonly used to indicate which women should be offered the oral glucose tolerance test (OGTT) to diagnose gestational diabetes (GDM). Evidence regarding these risk factors is limited however. We conducted a systematic review (SR) and meta-analysis and individual participant data (IPD) analysis to evaluate the performance of risk factors in identifying women with GDM.

METHODS

We searched MEDLINE, Medline in Process, Embase, Maternity and Infant Care and the Cochrane Central Register of Controlled Trials (CENTRAL) up to August 2016 and conducted additional reference checking. We included observational, cohort, case-control and cross-sectional studies reporting the performance characteristics of risk factors used to identify women at high risk of GDM. We had access to IPD from the Born in Bradford and Atlantic Diabetes in Pregnancy cohorts, all pregnant women in the two cohorts with data on risk factors and OGTT results were included.

RESULTS

Twenty nine published studies with 211,698 women for the SR and a further 14,103 women from two birth cohorts (Born in Bradford and the Atlantic Diabetes in Pregnancy study) for the IPD analysis were included. Six studies assessed the screening performance of guidelines; six examined combinations of risk factors; eight evaluated the number of risk factors and nine examined prediction models or scores. Meta-analysis using data from published studies suggests that irrespective of the method used, risk factors do not identify women with GDM well. Using IPD and combining risk factors to produce the highest sensitivities, results in low specificities (and so higher false positives). Strategies that use the risk factors of age (>25 or >30) and BMI (>25 or 30) perform as well as other strategies with additional risk factors included.

CONCLUSIONS

Risk factor screening methods are poor predictors of which pregnant women will be diagnosed with GDM. A simple approach of offering an OGTT to women 25 years or older and/or with a BMI of 25kg/m2 or more is as good as more complex risk prediction models. Research to identify more accurate (bio)markers is needed. Systematic Review Registration: PROSPERO CRD42013004608.

The Influence of Meteorological Factors and Atmospheric Pollutants on the Risk of Preterm Birth

Atmospheric pollutants and meteorological conditions are suspected to be causes of preterm birth. We aimed to characterize their possible association with the risk of preterm birth (defined as birth occurring before 37 completed gestational weeks). We pooled individual data from 13 birth cohorts in 11 European countries (71,493 births from the period 1994-2011, European Study of Cohorts for Air Pollution Effects (ESCAPE)). City-specific meteorological data from routine monitors were averaged over time windows spanning from 1 week to the whole pregnancy. Atmospheric pollution measurements (nitrogen oxides and particulate matter) were combined with data from permanent monitors and land-use data into seasonally adjusted land-use regression models. Preterm birth risks associated with air pollution and meteorological factors were estimated using adjusted discrete-time Cox models. The frequency of preterm birth was 5.0%. Preterm birth risk tended to increase with first-trimester average atmospheric pressure (odds ratio per 5-mbar increase = 1.06, 95% confidence interval: 1.01, 1.11), which could not be distinguished from altitude. There was also some evidence of an increase in preterm birth risk with first-trimester average temperature in the -5°C to 15°C range, with a plateau afterwards (spline coding, P = 0.08). No evidence of adverse association with atmospheric pollutants was observed. Our study lends support for an increase in preterm birth risk with atmospheric pressure.

Hyperglycaemia and risk of adverse perinatal outcomes: systematic review and meta-analysis

OBJECTIVES

 To assess the association between maternal glucose concentrations and adverse perinatal outcomes in women without gestational or existing diabetes and to determine whether clear thresholds for identifying women at risk of perinatal outcomes can be identified.

DESIGN

 Systematic review and meta-analysis of prospective cohort studies and control arms of randomised trials.

DATA SOURCES

 Databases including Medline and Embase were searched up to October 2014 and combined with individual participant data from two additional birth cohorts.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

 Studies including pregnant women with oral glucose tolerance (OGTT) or challenge (OGCT) test results, with data on at least one adverse perinatal outcome.

APPRAISAL AND DATA EXTRACTION

 Glucose test results were extracted for OGCT (50 g) and OGTT (75 g and 100 g) at fasting and one and two hour post-load timings. Data were extracted on induction of labour; caesarean and instrumental delivery; pregnancy induced hypertension; pre-eclampsia; macrosomia; large for gestational age; preterm birth; birth injury; and neonatal hypoglycaemia. Risk of bias was assessed with a modified version of the critical appraisal skills programme and quality in prognostic studies tools.

RESULTS

 25 reports from 23 published studies and two individual participant data cohorts were included, with up to 207 172 women (numbers varied by the test and outcome analysed in the meta-analyses). Overall most studies were judged as having a low risk of bias. There were positive linear associations with caesarean section, induction of labour, large for gestational age, macrosomia, and shoulder dystocia for all glucose exposures across the distribution of glucose concentrations. There was no clear evidence of a threshold effect. In general, associations were stronger for fasting concentration than for post-load concentration. For example, the odds ratios for large for gestational age per 1 mmol/L increase of fasting and two hour post-load glucose concentrations (after a 75 g OGTT) were 2.15 (95% confidence interval 1.60 to 2.91) and 1.20 (1.13 to 1.28), respectively. Heterogeneity was low between studies in all analyses.

CONCLUSIONS

 This review and meta-analysis identified a large number of studies in various countries. There was a graded linear association between fasting and post-load glucose concentration across the whole glucose distribution and most adverse perinatal outcomes in women without pre-existing or gestational diabetes. The lack of a clear threshold at which risk increases means that decisions regarding thresholds for diagnosing gestational diabetes are somewhat arbitrary. Research should now investigate the clinical and cost-effectiveness of applying different glucose thresholds for diagnosis of gestational diabetes on perinatal and longer term outcomes.

SYSTEMATIC REVIEW REGISTRATION

 PROSPERO CRD42013004608.

Pregnancy at very advanced maternal age: a UK population-based cohort study

Objectives

To describe the characteristics, management and outcomes of women giving birth at advanced maternal age (≥48 years).

Design

Population‐based cohort study using the UK Obstetric Surveillance System (UKOSS).

Setting

All UK hospitals with obstetrician‐led maternity units.

Population

Women delivering at advanced maternal age (≥48 years) in the UK between July 2013 and June 2014 (n = 233) and 454 comparison women.

Methods

Cohort and comparison group identification through the UKOSS monthly mailing.

Main outcome measures

Pregnancy complications.

Results

Older women were more likely than comparison women to be overweight (33% versus 23%, P = 0.0011) or obese (23% versus 19%, P = 0.0318), nulliparous (53% versus 44%, P = 0.0299), have pre‐existing medical conditions (44% versus 28%, P < 0.0001), a multiple pregnancy (18% versus 2%, P < 0.0001), and conceived following assisted conception (78% versus 4%, P < 0.0001). Older women appeared more likely than comparison women to have pregnancy complications including gestational hypertensive disorders, gestational diabetes, postpartum haemorrhage, caesarean delivery, iatrogenic and spontaneous preterm delivery on univariable analysis and after adjustment for demographic and medical factors. However, adjustment for multiple pregnancy or use of assisted conception attenuated most effects, with significant associations remaining only with gestational diabetes (adjusted odds ratio [aOR] 4.81, 95% CI 1.93–12.00), caesarean delivery (aOR 2.78, 95% CI 1.44–5.37) and admission to an intensive care unit (aOR 33.53, 95% CI 2.73–412.24).

Conclusions

Women giving birth at advanced maternal age have higher risks of a range of pregnancy complications. Many of the increased risks appear to be explained by multiple pregnancy or use of assisted conception.

Tweetable abstract

The pregnancy complications in women giving birth aged 48 or over are mostly explained by multiple pregnancy.

The pregnancy complications in women giving birth aged 48 or over are mostly explained by multiple pregnancy.

Examining the impact of introducing ICD-MM on observed trends in maternal mortality rates in the UK 2003-13

BACKGROUND

The causes of maternal death are now classified internationally according to ICD-MM. One significant change with the introduction of ICD-MM in 2012 was the reclassification of maternal suicide from the indirect group to the direct group. This has led to concerns about the impact of this reclassification on calculated mortality rates. The aim of this analysis was to examine the trends in maternal deaths in the UK over the past 10 years, and to investigate the impact of reclassification using ICD-MM on the observed rates.

METHODS

Data about all maternal deaths between 2003-13 in the UK were included in this analysis. Data about maternal deaths occurring prior to 2009 were obtained from previously published reports. The deaths of women from 2009-13 during or after pregnancy were identified through the MBRRACE-UK Confidential Enquiry into Maternal Deaths. The underlying causes of maternal death were reclassified from a disease-based system to ICD-MM. Maternal mortality rates with 95 % confidence intervals were calculated using national data on the number of maternities as the denominator. Rate ratios with 95 % CI were calculated to compare the change in rates of maternal death as per ICD-MM relative to the old classification system.

RESULTS

There was a decrease in the maternal death rate between 2003-05 and 2011-13 (rate ratio (RR) 0.65; 95 % CI 0.54-0.77 comparing 2003-5 with 2011-13; p = 0.005 for trend over time). The direct maternal death rate calculated using the old classification decreased with a RR of 0.47 (95 % CI 0.34-0.63) when comparing 2011-13 with 2003-05; p = 0.005 for trend over time. Reclassification using ICD-MM made little material difference to the observed trend in direct maternal death rates, RR = 0.51 (95 % CI 0.39-0.68) when comparing 2003-5 with 2011-13; p = 0.005 for trend over time.

CONCLUSIONS

The impact of reclassifying maternal deaths according to ICD-MM in the UK was minimal. However, such reclassification raises awareness of maternal suicides and hence is the first step to actions to prevent women dying by suicide in the future. Recognising and acknowledging these women's deaths is more important than concerns over the impact reclassification using ICD-MM might have on reported maternal death rates.

Association between hyperglycaemia and adverse perinatal outcomes in south Asian and white British women: analysis of data from the Born in Bradford cohort

BACKGROUND

Diagnosis of gestational diabetes predicts risk of infants who are large for gestational age (LGA) and with high adiposity, which in turn aims to predict a future risk of obesity in the offspring. South Asian women have higher risk of gestational diabetes, lower risk of LGA, and on average give birth to infants with greater adiposity than do white European women. Whether the same diagnostic criteria for gestational diabetes should apply to both groups of women is unclear. We aimed to assess the association between maternal glucose and adverse perinatal outcomes to ascertain whether thresholds used to diagnose gestational diabetes should differ between south Asian and white British women. We also aimed to assess whether ethnic origin affected prevalence of gestational diabetes irrespective of criteria used.

METHODS

We used data (including results of a 26-28 week gestation oral glucose tolerance test) of women from the Born in Bradford study, a prospective study that recruited women attending the antenatal clinic at the Bradford Royal Infirmary, UK, between 2007 and 2011 and who intended to give birth to their infant in that hospital. We studied the association between fasting and 2 h post-load glucose and three primary outcomes (LGA [defined as birthweight >90th percentile for gestational age], high infant adiposity [sum of skinfolds >90th percentile for gestational age], and caesarean section). We calculated adjusted odds ratios (ORs) and their 95% confidence intervals (CIs) for a 1 SD increase in fasting and post-load glucose. We established fasting and post-load glucose thresholds that equated to an OR of 1·75 for LGA and high infant adiposity in each group of women to identify ethnic-specific criteria for diagnosis of gestational diabetes.

FINDINGS

Of 13,773 pregnancies, 3420 were excluded from analyses. Of 10,353 eligible pregnancies, 4088 women were white British, 5408 were south Asian, and 857 were of other ethnic origin. The adjusted ORs of LGA per 1 SD fasting glucose were 1·22 (95% CI 1·08-1·38) in white British women and 1·43 (1·23-1·67) in south Asian women (pinteraction with ethnicity = 0·39). Results for high infant adiposity were 1·35 (1·23-1·49) and 1·35 (1·18-1·54; pinteraction with ethnicity=0·98), and for caesarean section they were 1·06 (0·97-1·16) and 1·11 (1·02-1·20; pinteraction with ethnicity=0·47). Associations between post-load glucose and the three primary outcomes were weaker than for fasting glucose. A fasting glucose concentration of 5·4 mmol/L or a 2 h post-load level of 7·5 mmol/L identified white British women with 75% or higher relative risk of LGA or high infant adiposity; in south Asian women, the cutoffs were 5·2 mmol/L or 7·2 mml/L; in the whole cohort, the cutoffs were 5·3 mmol/L or 7·5 mml/L. The prevalence of gestational diabetes in our cohort ranged from 1·2% to 8·7% in white British women and 4% to 24% in south Asian women using six different criteria. Compared with the application of our whole-cohort criteria, use of our ethnic-specific criteria increased the prevalence of gestational diabetes in south Asian women from 17·4% (95% CI 16·4-18·4) to 24·2% (23·1-25·3).

INTERPRETATION

Our data support the use of lower fasting and post-load glucose thresholds to diagnose gestational diabetes in south Asian than white British women. They also suggest that diagnostic criteria for gestational diabetes recommended by UK NICE might underestimate the prevalence of gestational diabetes compared with our criteria or those recommended by the International Association of Diabetes and Pregnancy Study Groups and WHO, especially in south Asian women.

FUNDING

The National Institute for Health Research.

Small-for-gestational age and large-for-gestational age thresholds to predict infants at risk of adverse delivery and neonatal outcomes: are current charts adequate? An observational study from the Born in Bradford cohort

OBJECTIVES

Construct an ethnic-specific chart and compare the prediction of adverse outcomes using this chart with the clinically recommended UK-WHO and customised birth weight charts using cut-offs for small-for-gestational age (SGA: birth weight <10th centile) and large-for-gestational age (LGA: birth weight >90th centile).

DESIGN

Prospective cohort study.

SETTING

Born in Bradford (BiB) study, UK.

PARTICIPANTS

3980 White British and 4448 Pakistani infants with complete data for gestational age, birth weight, ethnicity, maternal height, weight and parity.

MAIN OUTCOME MEASURES

Prevalence of SGA and LGA, using the three charts and indicators of diagnostic utility (sensitivity, specificity and area under the receiver operating characteristic (AUROC)) of these chart-specific cut-offs to predict delivery and neonatal outcomes and a composite outcome.

RESULTS

In White British and Pakistani infants, the prevalence of SGA and LGA differed depending on the chart used. Increased risk of SGA was observed when using the UK-WHO and customised charts as opposed to the ethnic-specific chart, while the opposite was apparent when classifying LGA infants. However, the predictive utility of all three charts to identify adverse clinical outcomes was poor, with only the prediction of shoulder dystocia achieving an AUROC>0.62 on all three charts.

CONCLUSIONS

Despite being recommended in national clinical guidelines, the UK-WHO and customised birth weight charts perform poorly at identifying infants at risk of adverse neonatal outcomes. Being small or large may increase the risk of an adverse outcome; however, size alone is not sensitive or specific enough with current detection to be useful. However, a significant amount of missing data for some of the outcomes may have limited the power needed to determine true associations.

Is objective and accurate cognitive assessment across the menstrual cycle possible? A feasibility study

Objectives:

Variation in plasma hormone levels influences the neurobiology of brain regions involved in cognition and emotion processing. Fluctuations in hormone levels across the menstrual cycle could therefore alter cognitive performance and wellbeing; reports have provided conflicting results, however. The aim of this study was to assess whether objective assessment of cognitive performance and self-reported wellbeing during the follicular and luteal phases of the menstrual cycle is feasible and investigate the possible reasons for variation in effects previously reported.

Methods:

The Cambridge Neuropsychological Test Automated Battery and Edinburgh Postnatal Depression Scale were used to assess the cognitive performance and wellbeing of 12 women. Data were analysed by self-reported and hormone-estimated phases of the menstrual cycle.

Results:

Recruitment to the study and assessment of cognition and wellbeing was without issue. Plasma hormone and peptide estimation showed substantial individual variation and suggests inaccuracy in self-reported menstrual phase estimation.

Conclusion:

Objective assessment of cognitive performance and self-assessed wellbeing across the menstrual cycle is feasible. Grouping data by hormonal profile rather by self-reported phase estimation may influence phase-mediated results. Future studies should use plasma hormone and peptide profiles to estimate cycle phase and group data for analyses.

Pregnancy glycaemia and cord-blood levels of insulin and leptin in Pakistani and white British mother-offspring pairs: findings from a prospective pregnancy cohort

AIMS/HYPOTHESIS

To determine the extent to which gestational fasting and postload levels of glucose explain differences in infant fat mass between UK-born Pakistani and white British infants.

METHODS

Analyses were undertaken in a prospective pregnancy cohort study of 1,415 women and their singleton live-born infants (629 white British and 786 Pakistani). Infant fat mass was assessed by cord-blood leptin levels and fetal insulin secretion by cord-blood insulin levels. Maternal OGTTs were completed at 26-28 weeks of gestation.

RESULTS

Pakistani women had higher fasting and postload glucose levels and greater incidence of gestational diabetes than white British women. Higher fasting and postload glucose levels were associated with higher cord-blood levels of insulin and leptin in all participants, irrespective of ethnicity. Cord-blood leptin levels were 16% (95% CI 6, 26) higher in Pakistani than in white British infants. After adjustment for fasting glucose levels, this difference attenuated to 7% (-3, 16), and with additional adjustment for cord-blood insulin levels it attenuated further to 5% (-4, 14). Path analyses supported the hypothesis that fasting glucose levels mediate the relationship of Pakistani ethnicity to greater fat mass at birth, as measured by cord-blood leptin levels; on average, 19% of this mediation involved fetal insulin secretion. Postload glucose levels did not act as an important mediator of ethnic differences in cord-blood leptin levels. Results were very similar when 130 women with gestational diabetes were removed.

CONCLUSIONS/INTERPRETATION

These novel findings suggest a role of maternal pregnancy glycaemia in mediating differences in fat mass between Pakistani and white British infants.

Experiences and outcomes of maternal Ramadan fasting during pregnancy: results from a sub-cohort of the Born in Bradford birth cohort study

BACKGROUND

Observing the fast during the holy month of Ramadan is one of the five pillars of Islam. Although pregnant women and those with pre-existing illness are exempted from fasting many still choose to fast during this time. The fasting behaviours of pregnant Muslim women resident in Western countries remain largely unexplored and relationships between fasting behaviour and offspring health outcomes remain contentious. This study was undertaken to assess the prevalence, characteristics of fasting behaviours and offspring health outcomes in Asian and Asian British Muslim women within a UK birth cohort.

METHODS

Prospective cohort study conducted at the Bradford Royal Infirmary UK from October to December 2010 comprising 310 pregnant Muslim women of Asian or Asian British ethnicity that had a live singleton birth at the Bradford Royal Infirmary. The main outcome of the study was the decision to fast or not during Ramadan. Secondary outcomes were preterm births and mean birthweight. Logistic regression analyses were used to investigate the relationship between covariables of interest and women's decision to fast or not fast. Logistic regression was also used to investigate the relationship between covariables and preterm birth as well as low birth weight.

RESULTS

Mutually adjusted analysis showed that the odds of any fasting were higher for women with an obese BMI at booking compared to women with a normal BMI, (OR 2.78 (95% C.I. 1.29-5.97)), for multiparous compared to nulliparous women(OR 3.69 (95% C.I. 1.38-9.86)), and for Bangladeshi origin women compared to Pakistani origin women (OR 3.77 (95% C.I. 1.04-13.65)). Odds of fasting were lower in women with higher levels of education (OR 0.40 (95% C.I. 0.18-0.91)) and with increasing maternal age (OR 0.87 (95% C.I. 0.80-0.94). No associations were observed between fasting and health outcomes in the offspring.

CONCLUSIONS

Pregnant Muslim women residing in the UK who fasted during Ramadan differed by social, demographic and lifestyle characteristics compared to their non-fasting peers. Fasting was not found to be associated with adverse birth outcomes in this sample although these results require confirmation using reported fasting data in a larger sample before the safety of fasting during pregnancy can be established.

Evaluation of the impact of universal testing for gestational diabetes mellitus on maternal and neonatal health outcomes: a retrospective analysis

BACKGROUND

Gestational diabetes (GDM) affects a substantial proportion of women in pregnancy and is associated with increased risk of adverse perinatal and long term outcomes. Treatment seems to improve perinatal outcomes, the relative effectiveness of different strategies for identifying women with GDM however is less clear.This paper describes an evaluation of the impact of a change in policy from selective risk factor based offering, to universal offering of an oral glucose tolerance test (OGTT) to identify women with GDM on maternal and neonatal outcomes.

METHODS

Retrospective six year analysis of 35,674 births at the Women's and Newborn unit, Bradford Royal Infirmary, United Kingdom.

RESULTS

The proportion of the whole obstetric population diagnosed with GDM increased almost fourfold following universal offering of an OGTT compared to selective offering of an OGTT; Rate Ratio (RR) 3.75 (95% CI 3.28 to 4.29), the proportion identified with severe hyperglycaemia doubled following the policy change; 1.96 (1.50 to 2.58). The case detection rate however, for GDM in the whole population and severe hyperglycaemia in those with GDM reduced by 50-60%; 0.40 (0.35 to 0.46) and 0.51 (0.39 to 0.67) respectively. Universally offering an OGTT was associated with an increased induction of labour rate in the whole obstetric population and in women with GDM; 1.43 (1.35 to 1.50) and 1.21 (1.00 to1.49) respectively. Caesarean section, macrosomia and perinatal mortality rates in the whole population were similar. For women with GDM, rate of caesarean section; 0.70 (0.57 to 0.87), macrosomia; 0.22 (0.15 to 0.34) and perinatal mortality 0.12 (0.03 to 0.46) decreased following the policy change.

CONCLUSIONS

Universally offering an OGTT was associated with increased identification of women with GDM and severe hyperglycaemia and with neonatal benefits for those with GDM. There was no evidence of benefit or adverse effects in neonatal outcomes in the whole obstetric population.

A comparison of South Asian specific and established BMI thresholds for determining obesity prevalence in pregnancy and predicting pregnancy complications: findings from the Born in Bradford cohort

OBJECTIVE

To describe how maternal obesity prevalence varies by established international and South Asian specific body mass index (BMI) cut-offs in women of Pakistani origin and investigate whether different BMI thresholds can help to identify women at risk of adverse pregnancy and birth outcomes.

DESIGN

Prospective bi-ethnic birth cohort study (the Born in Bradford (BiB) cohort).

SETTING

Bradford, a deprived city in the North of the UK.

PARTICIPANTS

A total of 8478 South Asian and White British pregnant women participated in the BiB cohort study.

MAIN OUTCOME MEASURES

Maternal obesity prevalence; prevalence of known obesity-related adverse pregnancy outcomes: mode of birth, hypertensive disorders of pregnancy (HDP), gestational diabetes, macrosomia and pre-term births.

RESULTS

Application of South Asian BMI cut-offs increased prevalence of obesity in Pakistani women from 18.8 (95% confidence interval (CI) 17.6-19.9) to 30.9% (95% CI 29.5-32.2). With the exception of pre-term births, there was a positive linear relationship between BMI and prevalence of adverse pregnancy and birth outcomes, across almost the whole BMI distribution. Risk of gestational diabetes and HDP increased more sharply in Pakistani women after a BMI threshold of at least 30 kg m(-2), but there was no evidence of a sharp increase in any risk factors at the new, lower thresholds suggested for use in South Asian women. BMI was a good single predictor of outcomes (area under the receiver operating curve: 0.596-0.685 for different outcomes); prediction was more discriminatory and accurate with BMI as a continuous variable than as a binary variable for any possible cut-off point.

CONCLUSION

Applying the new South Asian threshold to pregnant women would markedly increase those who were referred for monitoring and lifestyle advice. However, our results suggest that lowering the BMI threshold in South Asian women would not improve the predictive ability for identifying those who were at risk of adverse pregnancy outcomes.

Modelling foetal growth in a bi-ethnic sample: results from the Born in Bradford (BiB) birth cohort

BACKGROUND

Attempts to explain the increased risk for metabolic disorders observed in South Asians have focused on the "South Asian" phenotype at birth and subsequent post-natal growth, with little research on pre-natal growth.

AIM

To identify whether divergent growth patterns exist for foetal weight, head (HC) and abdominal circumferences (AC) in a sample of Pakistani and White British foetuses.

SUBJECTS AND METHODS

Models were based on 5553 (weight), 5154 (HC) and 5099 (AC) foetuses from the Born in Bradford birth cohort. Fractional polynomials and mixed effects models were employed to determine growth patterns from ~15 weeks of gestation-birth.

RESULTS

Pakistani foetuses were significantly smaller and lighter as early as 20 weeks. However, there was no ethnic difference in the growth patterns of weight and HC. For AC, Pakistani foetuses displayed a trend for reduced growth in the final trimester.

CONCLUSION

As the pattern of weight and HC growth was not significantly different during the period under investigation, the mechanism culminating in the reduced Pakistani size at birth may act earlier in gestation. Reduced AC growth in Pakistanis may represent reduced growth of the visceral organs, with consequences for post-natal liver metabolism and renal function.

Maternal sepsis: a Scottish population-based case-control study

OBJECTIVE

To describe the risk of maternal sepsis associated with obesity and other understudied risk factors such as operative vaginal delivery.

DESIGN

Population-based, case-control study.

SETTING

North NHS region of Scotland.

POPULATION

All cases of pregnant, intrapartum and postpartum women with International Classification of Disease-9 codes for sepsis or severe sepsis recorded in the Aberdeen Maternal and Neonatal Databank (AMND) from 1986 to 2009. Four controls per case selected from the AMND were frequency matched on year-of-delivery.

METHODS

Cases and controls were compared; significant variables from univariable regression were adjusted in a multivariable logistic regression model.

MAIN OUTCOME MEASURES

Dependent variables were uncomplicated sepsis or severe ('near-miss') sepsis. Independent variables were demographic, medical and clinical delivery characteristics. Unadjusted and adjusted odds ratios (OR) with 95% confidence intervals (95% CI) are reported.

RESULTS

Controlling for mode of delivery and demographic and clinical factors, obese women had twice the odds of uncomplicated sepsis (OR 2.12; 95% CI 1.14-3.89) compared with women of normal weight. Age <25 years (OR 5.15; 95% CI 2.43-10.90) and operative vaginal delivery (OR 2.20; 95% CI 1.02-4.87) were also significant predictors of sepsis. Known risk factors for maternal sepsis were also significant in this study (OR for uncomplicated and severe sepsis respectively): multiparity (OR 6.29, 12.04), anaemia (OR 3.43, 18.49), labour induction (OR 3.92 severe only), caesarean section (OR 3.23, 13.35), and preterm birth (OR 2.46 uncomplicated only).

CONCLUSIONS

Obesity, operative vaginal delivery and age <25 years are significant risk factors for sepsis and should be considered in clinical obstetric care.

Measuring placental transfusion for term births: weighing babies with cord intact

OBJECTIVE

To estimate the volume and duration of placental transfusion at term.

DESIGN

Prospective observational study.

SETTING

Maternity unit in Bradford, UK.

POPULATION

Twenty-six term births.

METHODS

Babies were weighed with umbilical cord intact using digital scales that record an average weight every 2 seconds. Placental transfusion was calculated from the change in weight between birth and either cord clamping or when weighing stopped. Start and end weights were estimated using both a B-spline and inspection of graphs. Weight was converted to volume, 1 ml of blood weighing 1.05 g.

MAIN OUTCOME MEASURES

Volume and duration of placental transfusion.

RESULTS

Twenty-six babies were weighed. Start weights were difficult to determine because of artefacts in the data as the baby was placed on the scales and wrapped. The mean difference in weight was 116 g [95% confidence interval (CI), 72-160 g] using the B-spline and 87 g (95% CI, 64-110 g) using inspection. Converting this to the mean volume of placental transfusion gave 110 ml (95% CI, 69-152 ml) and 83 ml (95% CI, 61-106 ml), respectively. Placental transfusion was usually complete by 2 minutes, but sometimes continued for up to 5 minutes. Based on the B-spline, placental transfusion contributed 32 ml (95% CI, 30-33 ml) per kilogram of birth weight to blood volume, but 24 ml (95% CI, 19-32 ml) based on inspection. This equates to 40% (95% CI, 37-42%) and 30% (24-40%), respectively, of total potential blood volume.

CONCLUSION

Inspection of the graphs probably underestimates placental transfusion. For term infants, placental transfusion contributes between one-third and one-quarter of total potential blood volume at birth.

Care during the third stage of labour: a postal survey of UK midwives and obstetricians

BACKGROUND

There are two approaches to care during the third stage of labour: Active management includes three components: administration of a prophylactic uterotonic drug, cord clamping and controlled cord traction. For physiological care, intervention occurs only if there is clinical need. Evidence to guide care during the third stage is limited and there is variation in recommendations which may contribute to differences in practice. This paper describes current UK practice during the third stage of labour.

METHODS

A postal survey of 2230 fellows and members of the Royal College of Obstetricians and Gynaecologists (RCOG) and 2400 members of the Royal College of Midwives was undertaken. Respondents were asked about care during the third stage of labour, for vaginal and caesarean births and their views on the need for more evidence to guide care in the third stage. The data were analysed in Excel and presented as descriptive statistics.

RESULTS

1189 (53%) fellows and members of the RCOG and 1702 (71%) midwives responded, of whom 926 (78%) and 1297 (76%) respectively had conducted or supervised births in the last year. 93% (863/926) of obstetricians and 73% (942/1297) of midwives report 'always or usually' using active management. 66% (611/926) of obstetricians and 33% (430/1297) of midwives give the uterotonic drug with delivery of the anterior shoulder; this was intramuscular Syntometrine(R) for 79% (728/926) and 86% (1118/1293) respectively. For term births, 74% (682/926) of obstetricians and 41% (526/1297) of midwives clamp the cord within 20 seconds, as do 57% (523/926) and 55% (707/1297) for preterm births. Controlled cord traction was used by 94% of both obstetricians and midwives. For caesarean births, intravenous oxytocin was the uterotonic used by 90% (837/926) of obstetricians; 79% (726/926) clamp the cord within 20 seconds for term births as do 63% (576/926) for preterm births.Physiological management was used 'always or usually' by 2% (21/926) of obstetricians and 9% (121/1297) of midwives. 81% (747/926) of obstetricians and 89% (1151/1297) of midwives thought more evidence from randomised trials was needed; the most popular question was when is best to clamp the cord.

CONCLUSIONS

Active management of the third stage of labour is widely used by both obstetricians and midwives in the UK. Syntometrine(R) is usually used for vaginal births and oxytocin for caesarean births; when this is given and when the cord is clamped varies.

Obstetric services in the UK: what we need now

Pregnancy and childbirth should be a safe and memorable experience for both women and their partners. This article discusses the current position of maternity services, their strengths and limitations, and suggests future directions required to improve these services further.

Do clinical trials improve quality of care? A comparison of clinical processes and outcomes in patients in a clinical trial and similar patients outside a trial where both groups are managed according to a strict protocol

BACKGROUND

The conventional view that participants in randomised controlled trials sacrifice themselves for the good of future patients is challenged by increasing evidence to suggest that individual patients benefit from participation in trials.

OBJECTIVE

To test the hypothesis that trial participants receive higher quality care and, as a consequence, have better outcomes than patients receiving guideline driven routine care.

METHODS

Retrospective comparative study of 408 women with pre-eclampsia all managed according to a strict protocol. Trial participants were 86 women who participated in a multicentre randomised controlled trial of magnesium sulphate for the treatment of pre-eclampsia (Magpie Trial); 322 non-participants formed the control group. Indicators of the process of care and clinical outcomes were compared between the two groups.

RESULTS

Trial participants were significantly more likely to have received daily blood tests (odds ratio (OR) 6.82, 95% CI 1.62 to 28.72) and had their respiration rate measured hourly (OR 3.42, 95% CI 1.69 to 6.92) than control patients. There were no significant differences in other markers of clinical process and no significant difference in clinical outcomes.

CONCLUSION

This study shows minor differences in process markers and no difference in clinical outcomes between patients in a clinical trial and patients receiving protocol driven care. The benefits of improved clinical care that have previously been associated with being in a trial may be explained by the use of clear clinical protocols. In routine practice, patients may be well advised to insist on treatment as part of a protocol.

In vitro susceptibilities in lymphocytes from mothers and cord blood to the monofunctional alkylating agent EMS

It has been reported that children may experience different levels of chemical exposures than adults and that their sensitivities to chemical toxins may be increased or decreased when compared to adults. The perinatal period is one period in which these susceptibilities may be examined. Midwives at the Bradford Royal Infirmary collected venous blood samples from mothers at the time of birth and venous cord blood post-delivery. Lymphocytes were isolated from both blood types and examined in the alkaline comet assay using the monofunctional alkylating agent ethyl methanesulphonate (EMS). There were no biologically significant differences when subjects were categorized into subgroups based on lifestyle habits and physical characteristics, and overall there were no statistically significant differences in levels of DNA damage in mothers (n=22) and babies (n=22), except at the basal level (P<0.05), but mean values in babies were always lower over the EMS dose range. Whole blood was used in the micronucleus (MN) assay, and there was a significantly (P<0.05) higher rate of MN in mothers (n=17), per 1000 binucleates, as compared with lymphocytes from their offspring (n=17) at the basal level. This may be accounted for by age and endogenous factors. Overall, this current study cannot provide statistically significant evidence that children have either increased or decreased levels of susceptibility to a chemical toxin in comparison to adults when EMS is examined in vitro.