Stillbirth: are we making more progress than we think? A retrospective cohort study.

OBJECTIVE: To quantify how the changing stillbirth risk profile of women is affecting the interpretation of the stillbirth rate. DESIGN: A retrospective, population-based cohort study from 1983 to 2018. SETTING: Victoria, Australia. POPULATION: A total of 2 419 923 births at ≥28 weeks of gestation. METHODS: Changes in maternal characteristics over time were assessed. A multivariable logistic regression model was developed for stillbirth, based on maternal characteristics in 1983-1987, and used to calculate individual predictive probabilities of stillbirth from the regression equation. The number of expected stillbirths per year as a result of the change in maternal demographics was then calculated, assuming no changes in care and in the associations between maternal characteristics and stillbirth over time. MAIN OUTCOME MEASURE: Stillbirth. RESULTS: Compared with 1983-1987, there were more women in older age groups giving birth, more nulliparous women, more indigenous women and women born in Oceania, Asia and Africa, more multiple pregnancies and more women with pre-existing diabetes in 2014-2018. Despite this, the rate of stillbirth fell from 5.42 per 1000 births in 1983 to 1.72 per 1000 births in 2018 (P < 0.001). Applying the multivariable logistic regression equation, derived from the 1983-87 data, to each year, had there been no changes in care or in the associations between maternal characteristics and stillbirth, the rate of stillbirth would have increased by 12%, from 4.94 per 1000 in 1983 to 5.54 per 1000 in 2018, as a result of the change in maternal characteristics. CONCLUSIONS: Population rates of stillbirth are falling faster than is generally appreciated. TWEETABLE ABSTRACT: Population reductions in stillbirth have been underestimated as a result of changing maternal characteristics.

Increasing obstetric intervention for fetal growth restriction is shifting birthweight centiles: a retrospective cohort study.

OBJECTIVE: To assess the impact of increasing obstetric intervention on birthweight centiles. DESIGN: Retrospective cohort study of births in five 2-year epochs: 1983-84, 1993-94, 2003-2004, 2013-2014 and 2016-2017. POPULATION: 665 205 singleton births at ≥32 weeks' gestation. SETTING: All maternity services in Victoria, Australia. METHODS: For each epoch, we calculated the birthweight cutoffs defining each birthweight centile at 34, 37 and 40 weeks' gestation. We calculated rates of iatrogenic delivery over time. We then calculated the number of babies whose birthweight would have classified them as ≥3rd centile based on 1983-84 centile definitions but as <3rd centile based on 2016-2017 centile definitions. MAIN OUTCOME MEASURES: Birthweight centile, and gestation at delivery. RESULTS: From 1983-84 to 2016-2017, the rate of iatrogenic delivery for singleton pregnancies increased at all term gestations: 1.6-6.4% at 37 weeks', 4.5-18.3% at 38 weeks', 7.6-23.9% at 39 weeks' and 18.4-25.1% at 40 weeks' (all P < 0.001). Over the same period, the birthweight cutoffs defining the 3rd, 5th and 10th centiles increased significantly at term, but not preterm, gestations. This led to increasing numbers of term births being classified as small for gestational age (SGA). Of the 2748 babies born in 2016-2017 at 37-39 weeks' gestation with a birthweight <3rd centile in that period, 1478 (53.8%) would have been classified as ≥3rd centile based on 1983-84 centile definitions. CONCLUSION: Increasing intervention is shifting the birthweight cutoffs that define birthweight centiles and thereby redefining what constitutes SGA. This undermines the use of population-derived birthweight centiles to audit clinical care. TWEETABLE ABSTRACT: Increasing obstetric intervention is shifting birthweight centiles and therefore definitions of normality.

Chronic hepatitis B infection and the risk of gestational diabetes: a cross-sectional study.

OBJECTIVE: An estimated two billion people worldwide live with hepatitis B virus (HBV) infection. Many of these are women of reproductive age. Studies that have examined pregnancy outcomes in women living with HBV have reported conflicting results in relation to the incidence of gestational diabetes (GDM). The aim of this study is to examine if gestational diabetes is more common in women with chronic HBV residing in a non-Asian country. DESIGN: Cross-sectional study. SETTING: Victoria, Australia. POPULATION: All singleton births between 2009 and 2017. METHODS: Poisson regression was performed to determine whether gestational diabetes is more common in women with HBV than in women without HBV taking into account other risk factors such as maternal age, body mass index (BMI), parity and country of birth. MAIN OUTCOME MEASURE: Gestational diabetes diagnosis in women with chronic HBV infection. RESULTS: For women with HBV, the unadjusted incidence risk ratio for GDM was 1.75 (95% CI 1.6-1.9). After adjusting for region of birth, BMI, parity, age and smoking, the adjusted incidence risk ratio was 1.2 (95% CI 1.1-1.3). The highest incidence (37.1%) of GDM was in women with HBV and a BMI of >40. CONCLUSIONS: The findings from this study confirm an association between HBV and GDM. TWEETABLE ABSTRACT: HBV is associated with GDM with an incidence risk ratio for GDM of 1.75 (95% CI 1.6-1.9).

Does public reporting of the detection of fetal growth restriction improve clinical outcomes: a retrospective cohort study.

OBJECTIVE: To assess the impact of publicly reporting a statewide fetal growth restriction (FGR) performance indicator. DESIGN: Retrospective cohort study from 2000 to 2017. SETTING: All maternity services in Victoria, Australia. POPULATION: A total of 1 231 415 singleton births at ≥32 weeks of gestation. METHODS: We performed an interrupted time-series analysis to assess the impact of publicly reporting an FGR performance indicator on the rate of detection for severe cases of small for gestational age (SGA). Rates of perinatal mortality and morbidity and obstetric intervention were assessed for severe SGA pregnancies and pregnancies delivered for suspected SGA. MAIN OUTCOME MEASURES: Gestation at delivery, obstetric management and perinatal outcome. RESULTS: The public reporting of a statewide FGR performance indicator was associated with a steeper reduction per quarter in the percentage of severe SGA undelivered by 40 weeks of gestation, from 0.13 to 0.51% (P = 0.001), and a decrease in the stillbirth rate by 3.3 per 1000 births among those babies (P = 0.01). Of babies delivered for suspected SGA, the percentage with birthweights ≥ 10th centile increased from 41.4% (n = 307) in 2000 to 53.3% (n = 1597) in 2017 (P < 0.001). Admissions to a neonatal intensive care unit for babies delivered for suspected SGA but with a birthweight ≥ 10th centile increased from 0.8 to 2.0% (P < 0.001). CONCLUSIONS: The public reporting of an FGR performance indicator has been associated with the improved detection of severe SGA and a decrease in the rate of stillbirth among those babies, but with an increase in the rate of iatrogenic birth for babies with normal growth. TWEETABLE ABSTRACT: The public reporting of hospital performance is associated with a reduction in stillbirth, but also with unintended interventions.

Routine weighing to reduce excessive antenatal weight gain: a randomised controlled trial.

OBJECTIVE: To assess whether routinely weighing women at each antenatal visit leads to a difference in gestational weight gain and weight gain within the Institute of Medicine (IOM) recommendation. DESIGN: A randomised controlled trial. SETTING: Antenatal clinics in a tertiary obstetric hospital in Melbourne, Australia. POPULATION: Healthy women were enrolled during their antenatal booking visit if they were between 18 and 45 years of age, were <21 weeks' gestation with a singleton pregnancy. METHODS: The intervention was weighing at each antenatal clinic appointment followed by counselling by their treating clinician according to IOM gestational weight gain guidelines. The control group had standard antenatal care comprising recording weight at booking and then at 36 weeks. Primary analysis was by intention-to-treat. OUTCOME: The primary outcome was difference in mean weight gain between groups. An important secondary outcome was gestational weight gain within IOM recommendations. Secondary outcomes also included maternal or neonatal morbidity. RESULTS: Seven hundred and eighty two women consented to take part and 386 were randomised to the intervention group and 396 to the control group. There was no significant difference in weight gain between the intervention group (0.54 kg/week) compared with the control group (0.53 kg/week) (P = 0.63). A similar proportion of women gained more weight than the IOM recommended range: 75% in the intervention group and 71% in the control group (P = 0.21). There were no significant differences in secondary outcomes between the two groups. CONCLUSION: We found no evidence that regular weighing in antenatal clinics changed weight gain or was effective at reducing excessive gestational weight gain.

Women's opinions on being weighed at routine antenatal visits.

OBJECTIVE: To assess the opinions of pregnant women regarding their weight gain and to assess the level of satisfaction and anxiety provoked by being weighed in clinic. DESIGN: Questionnaires were given to women participating in a randomised controlled trial comparing routine weighing in the antenatal clinic with standard care. SETTING: A tertiary hospital antenatal clinic in Melbourne, Australia. POPULATION: In all, 782 healthy pregnant women participated in the randomised controlled trial and 586 responded to the questionnaire. METHODS: A questionnaire was offered to all participants at 36 weeks of gestation gauging their satisfaction with their weight gain during pregnancy. The intervention group was asked about their level of satisfaction and anxiety provoked by being weighed in clinic. The control group was asked whether they would have liked to be weighed in clinic. Both groups were questioned about the influences on their weight gain. RESULTS: Women in both groups were satisfied with their weight gain during pregnancy. Seventy-three percent of women in the intervention group were very comfortable with being weighed in clinic. Approximately half of those in the control group would have favoured being weighed. Twenty-one percent of women said other people influenced their weight gain; mostly family members and two-thirds of them encouraged weight gain. Less than half of the women in the study used weighing scales at home. CONCLUSION: Women were satisfied with being weighed antenatally and it did not cause anxiety. Pregnant women accepted the re-introduction of weighing in the antenatal clinic.

The effect of primary midwife-led care on women's experience of childbirth: results from the COSMOS randomised controlled trial.

OBJECTIVE: To determine the effect of primary midwife-led care ('caseload midwifery') on women's experiences of childbirth. DESIGN: Randomised controlled trial. SETTING: Tertiary care women's hospital in Melbourne, Australia. POPULATION: A total of 2314 low-risk pregnant women. METHODS: Women randomised to caseload care received antenatal, intrapartum and postpartum care from a primary midwife, with some care provided by a 'back-up' midwife. Women in standard care received midwifery-led care with varying levels of continuity, junior obstetric care or community-based medical care. MAIN OUTCOME MEASURES: The primary outcome of the study was caesarean section. This paper presents a secondary outcome, women's experience of childbirth. Women's views and experiences were sought using seven-point rating scales via postal questionnaires 2 months after the birth. RESULTS: A total of 2314 women were randomised between September 2007 and June 2010; 1156 to caseload and 1158 to standard care. Response rates to the follow-up questionnaire were 88 and 74%, respectively. Women in the caseload group were more positive about their overall birth experience than women in the standard care group (adjusted odds ratio 1.50, 95% CI 1.22-1.84). They also felt more in control during labour, were more proud of themselves, less anxious, and more likely to have a positive experience of pain. CONCLUSIONS: Compared with standard maternity care, caseload midwifery may improve women's experiences of childbirth. TWEETABLE ABSTRACT: Primary midwife-led care ('caseload midwifery') improves women's experiences of childbirth.

Disparities in pre-eclampsia and eclampsia among immigrant women giving birth in six industrialised countries.

OBJECTIVE: To assess disparities in pre-eclampsia and eclampsia among immigrant women from various world regions giving birth in six industrialised countries. DESIGN: Cross-country comparative study of linked population-based databases. SETTING: Provincial or regional obstetric delivery data from Australia, Canada, Spain and the USA and national data from Denmark and Sweden. POPULATION: All immigrant and non-immigrant women delivering in the six industrialised countries within the most recent 10-year period available to each participating centre (1995-2010). METHODS: Data was collected using standardised definitions of the outcomes and maternal regions of birth. Pooled data were analysed with multilevel models. Within-country analyses used stratified logistic regression to obtain odds ratios (OR) with 95% confidence intervals (95% CI). MAIN OUTCOME MEASURES: Pre-eclampsia, eclampsia and pre-eclampsia with prolonged hospitalisation (cases per 1000 deliveries). RESULTS: There were 9,028,802 deliveries (3,031,399 to immigrant women). Compared with immigrants from Western Europe, immigrants from Sub-Saharan Africa and Latin America & the Caribbean were at higher risk of pre-eclampsia (OR: 1.72; 95% CI: 1.63, 1.80 and 1.63; 95% CI: 1.57, 1.69) and eclampsia (OR: 2.12; 95% CI: 1.61, 2.79 and 1.55; 95% CI: 1.26, 1. 91), respectively, after adjustment for parity, maternal age and destination country. Compared with native-born women, European and East Asian immigrants were at lower risk in most industrialised countries. Spain exhibited the largest disparities and Australia the smallest. CONCLUSION: Immigrant women from Sub-Saharan Africa and Latin America & the Caribbean require increased surveillance due to a consistently high risk of pre-eclampsia and eclampsia.

Effects of continuity of care by a primary midwife (caseload midwifery) on caesarean section rates in women of low obstetric risk: the COSMOS randomised controlled trial.

OBJECTIVE: To determine whether primary midwife care (caseload midwifery) decreases the caesarean section rate compared with standard maternity care. DESIGN: Randomised controlled trial. SETTING: Tertiary-care women's hospital in Melbourne, Australia. POPULATION: A total of 2314 low-risk pregnant women. METHODS: Women randomised to caseload received antenatal, intrapartum and postpartum care from a primary midwife with some care by 'back-up' midwives. Women randomised to standard care received either midwifery or obstetric-trainee care with varying levels of continuity, or community-based general practitioner care. PRIMARY OUTCOME: caesarean birth. Secondary outcomes included instrumental vaginal births, analgesia, perineal trauma, induction of labour, infant admission to special/neonatal intensive care, gestational age, Apgar scores and birthweight. RESULTS: In total 2314 women were randomised-1156 to caseload and 1158 to standard care. Women allocated to caseload were less likely to have a caesarean section (19.4% versus 24.9%; risk ratio [RR] 0.78; 95% CI 0.67-0.91; P = 0.001); more likely to have a spontaneous vaginal birth (63.0% versus 55.7%; RR 1.13; 95% CI 1.06-1.21; P < 0.001); less likely to have epidural analgesia (30.5% versus 34.6%; RR 0.88; 95% CI 0.79-0.996; P = 0.04) and less likely to have an episiotomy (23.1% versus 29.4%; RR 0.79; 95% CI 0.67-0.92; P = 0.003). Infants of women allocated to caseload were less likely to be admitted to special or neonatal intensive care (4.0% versus 6.4%; RR 0.63; 95% CI 0.44-0.90; P = 0.01). No infant outcomes favoured standard care. CONCLUSION: In settings with a relatively high baseline caesarean section rate, caseload midwifery for women at low obstetric risk in early pregnancy shows promise for reducing caesarean births.