Association between intravenous fluids during labor and primary postpartum hemorrhage: A retrospective cohort study.

INTRODUCTION: There is a major research gap relating to the impact of intravenous (IV) fluids administration during labor on maternal and neonatal outcomes. It is biologically plausible that a relationship between volume of IV fluids and primary postpartum hemorrhage (PPH) exists. The primary objective of this study was to evaluate whether the administration of high-volume IV fluids during labor (≥ 2500 mL) increases the risk of primary PPH and other adverse outcomes for women with a term, singleton pregnancy, in comparison to low-volume IV fluids during labor (<2500 mL). MATERIAL AND METHODS: A retrospective cohort study was conducted at a tertiary referral hospital in Sydney, Australia between 1st September 2021 and 31st October 2022. Inclusion criteria were: women with a live singleton fetus in a cephalic presentation; planning a vaginal birth; and admitted for labor and birth care between 37 and 42 week gestation. The study factor was IV fluids during labor and the primary outcome was primary PPH ≥500 mL. Secondary outcomes included cesarean section and major perineal injury. Pregnancy, birth, and postnatal data were obtained from the hospital's electronic clinical database, electronic medical records, and paper fluid order documentation. Multivariable logistic regression and multiple imputation were used to explore the relationship between volume of IV fluids in labor and PPH. RESULTS: A total of 1023 participants were included of which 339 had a primary PPH (33.1%). There was no association between high-volume IV fluids and PPH after adjusting for demographic and clinical factors (adjusted odds ratio [ORadj]1.02 95% confidence interval [95%CI] 0.72, 1.44). However, there was a positive association between high-volume IV fluids and cesarean section (ORadj 1.99; 95%CI 1.4, 2.8). CONCLUSIONS: The findings of this research are important to further knowledge relating to the administration of IV fluids during labor. The findings emphasize the importance of accurately documenting IV fluids administration and identifies research priorities to enable us to better understand the broader implications of IV fluids administration on pregnancy and perinatal outcomes.

Factors influencing uptake of the COVID-19 vaccination among pregnant women in Australia: A cross-sectional survey.

BACKGROUND: Mounting evidence shows the risk of COVID-19 on perinatal outcomes, as well as the safety and efficacy of vaccination during pregnancy. However, little is known about vaccine uptake among pregnant women in Australia, including women who are culturally and linguistically diverse (CALD), and about sources of information pregnant women use when making decisions about vaccines. We aimed to determine the proportion of pregnant women who had been vaccinated and to identify factors associated with vaccine uptake or decline during pregnancy. METHOD: A cross-sectional, anonymous, online survey was conducted from October 2021 to January 2022 in two metropolitan hospitals in New South Wales, Australia. RESULTS: Of 914 pregnant women, 406 (44%) did not speak English at home. Overall, 101 (11%) received a vaccine prepregnancy and 699 (76%) during pregnancy. In the nonvaccinated cohort, 87 (76%) declined vaccination during pregnancy. The uptake was more than 87% among women during pregnancy who received information from government or health professional websites but 37% when received from personal blogs. The main reasons for vaccine uptake were (1) hearing that COVID-19 affects pregnant women, (2) being concerned about the COVID-19 outbreak, and (3) receiving vaccine recommendation from a general practitioner. In a multivariable logistic regression, three main factors associated with declining or feeling unsure about vaccination were (1) concerns about the safety of the COVID-19 vaccine, (2) lack of trust and being unsatisfied with the information received about COVID-19 vaccination during pregnancy, and (3) doubting the importance of COVID-19 vaccine. CONCLUSION: Clinicians play a critical role in counseling women to alleviate vaccine fear, support vaccine acceptance, and direct women to use reliable information sources, such as government and professional healthcare organizations, for information about vaccines.

Midwives' perspectives of intravenous fluid management and fluid balance documentation in labour: A qualitative reflexive thematic analysis study.

AIM: To describe current practice, examine the influences and explore barriers and facilitators to accurate documentation, for the administration of intravenous fluids during labour. DESIGN: A descriptive qualitative study was performed. METHODS: Qualitative semi-structured interviews were conducted with Registered Midwives working across Australia. Midwives were recruited via email and social media advertisements. A maximum variation sampling strategy was used to identify potential participants. Interview questions explored four main areas: (i) understanding of indications for IV fluids in labour; (ii) identification of current practice; (iii) barriers to documentation and (iv) benefits and complications of IV fluid administration. Reflexive thematic analysis of recorded-transcribed interviews was conducted. RESULTS: Eleven midwives were interviewed. Clinical practice variation across Australia was recognized. Midwives reported a potential risk of harm for women and babies and a current lack of evidence, education and clinical guidance contributing to uncertainty around the use of IV fluids in labour. Overall, eight major themes were identified: (i) A variable clinical practice; (ii) Triggers and habits; (iii) Workplace and professional culture; (iv) Foundational knowledge; (v) Perception of risk; (vi) Professional standards and regulations; (vii) The importance of monitoring maternal fluid balance and (viii) barriers and facilitators to fluid balance documentation. CONCLUSION: There was widespread clinical variation identified and midwives reported a potential risk of harm. The major themes identified will inform future quantitative research examining the impact of IV fluids in labour. IMPACT: The implications of this research are important and potentially far-reaching. The administration of IV fluids to women in labour is a common clinical intervention. However, there is limited evidence available to guide practice. This study highlights the need for greater education and evidence examining maternal and neonatal outcomes to provide improved clinical guidance.

Fertility preservation in gynaecology oncology patients: Experience from an Australian tertiary oncology centre.

BACKGROUND: Management for gynaecological cancers often includes removal of the reproductive organs and/or the use of gonadotoxic therapies resulting in sub-fertility. Oncofertility and discussion of fertility preservation in these patients is critical. AIM: To determine the rate of fertility preservation discussion among a cohort of patients with a gynaecological cancer and what determinants impact likelihood of a discussion. MATERIALS AND METHODS: A seven-year quantitative retrospective study was conducted at a single oncology centre, including 15-45 year old patients with a gynaecological cancer. The primary outcome was if a fertility preservation discussion occurred during a consultation. Secondary outcomes included if a referral was made and what fertility preservation services were undertaken. Determinants that impacted the likelihood of a fertility preservation discussion were analysed. RESULTS: One hundred and twenty-one patients were analysed. There were 84 (69%) patients who had a documented fertility preservation discussion, and 46% were referred to a fertility specialist for consultation. Age was a significant determinant, with patients aged 30-39 years of age more commonly having a fertility preservation discussion. Patients with a high-grade cancer compared to patients with a lower-grade cancer (grade one or two) were only a third as likely to have a discussion surrounding their fertility (odds ratio: 0.33, 95% CI: 0.13-0.86; P = 0.02). CONCLUSION: We conclude that rates of discussion around fertility options for patients with cancer are lower than the recommended guidelines. Oncofertility is an important discipline which we believe needs to be emphasised within the gynaecology oncology community and management of patients should include a multi-disciplinary team.

How do the M4 and M6 models perform in an Australian pregnancy of unknown location population?

BACKGROUND: The diagnosis of a pregnancy of unknown location (PUL) is made when there is an elevated serum ß human chorionic gonadotropin (ßhCG) and no pregnancy on transabdominal and transvaginal ultrasound. Most of these pregnancies end as intra-uterine pregnancies or unsuccessful pregnancies and can be safely managed expectantly. However, up to 20% of these women will have an ectopic pregnancy. Several mathematical models, including the M4 and M6 protocols, have been developed using biochemical markers to triage PUL presentations. This rationalises numbers of tests and visits made without compromising safety and allowing timely intervention. AIMS: We aimed to externally validate the M4 and M6 models in an Australian tertiary early pregnancy assessment service (EPAS). MATERIALS AND METHODS: We performed a retrospective single-centre cohort study across five years. Our study population included all women attending our EPAS with a PUL who had at least two serum ßhCG levels and one progesterone level measured. The M4 and M6 models were retrospectively applied. RESULTS: Of the 360 women in the study population, there were 26 confirmed ectopic pregnancies (7.2%) and six persisting PULs (2%). The M4 model had a sensitivity and specificity of 72%. The M6P model had a sensitivity of 91% and specificity of 63%. The M6P misclassified two ectopic pregnancies into the low-risk group, compared with seven in the M4 model. CONCLUSIONS: The M6P model has the highest sensitivity of the three models and a negative predictive value of 99%. These numbers are comparable to the original United Kingdom population. Further prospective validation is planned.

A survey of obstetricians' attitudes to induction of labour at 39 weeks gestation with the intention of reducing caesarean section rates.

BACKGROUND: Induction of labour (IOL) and caesarean section (CS) rates continue to increase in Australia, New Zealand and globally. There is evidence that CS rates are decreased in the context of medically indicated and elective IOL; therefore, the emerging concept of using IOL as means of preventing CS warrants investigation. AIMS: To assess obstetricians' opinions of elective IOL at 39 weeks gestation, its feasibility, generalisability and utility as a means of preventing CS in Australia and New Zealand. MATERIALS AND METHODS: A de-identified cross-sectional survey was distributed electronically to all Fellows and trainees of The Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG). The survey was voluntary and distributed with the approval of the RANZCOG Continuing Education Committee. The survey addressed opinions relating to rates of and indications for IOL, the perceived validity of those indications and explored the acceptability of using a screening tool to predict women at increased risk of intra-partum CS and tailoring obstetric management to include the option of IOL at 39 weeks gestation. RESULTS: The overall response rate was 34% (492/1423) (including trainees) and the response rate was 53% (394/750) for currently practising obstetricians. The majority (90%) of responders agreed on medical and clinical indications for IOL. There was no consensus on the validity of IOL if a woman were at apparent high risk of intra-partum CS; however, 81% (360/443) of clinicians would be interested in a tool that could predict those women at risk. CONCLUSIONS: There is heterogeneity of obstetrician's beliefs on using IOL at 39 weeks as a mechanism to reduce the CS rate.

New Australian birthweight centiles.

OBJECTIVES: To prepare more accurate population-based Australian birthweight centile charts by using the most recent population data available and by excluding pre-term deliveries by obstetric intervention of small for gestational age babies. DESIGN: Population-based retrospective observational study. SETTING: Australian Institute of Health and Welfare National Perinatal Data Collection. PARTICIPANTS: All singleton births in Australia of 23-42 completed weeks' gestation and with spontaneous onset of labour, 2004-2013. Births initiated by obstetric intervention were excluded to minimise the influence of decisions to deliver small for gestational age babies before term. MAIN OUTCOME MEASURES: Birthweight centile curves, by gestational age and sex. RESULTS: Gestational age, birthweight, sex, and labour onset data were available for 2 807 051 singleton live births; onset of labour was spontaneous for 1 582 137 births (56.4%). At pre-term gestational ages, the 10th centile was higher than the corresponding centile in previous Australian birthweight charts based upon all births. CONCLUSION: Current birthweight centile charts probably underestimate the incidence of intra-uterine growth restriction because obstetric interventions for delivering pre-term small for gestational age babies depress the curves at earlier gestational ages. Our curves circumvent this problem by excluding intervention-initiated births; they also incorporate more recent population data. These updated centile curves could facilitate more accurate diagnosis of small for gestational age babies in Australia.

Cesarean delivery: Trend in indications over three decades within a major city hospital network.

INTRODUCTION: The cesarean delivery rate has been increasing globally in recent decades. The reasons for this are complex and subject to ongoing debate. Investigation of the indications for cesarean delivery and how these have changed over an extended period of time could provide insight into the reasons for changing obstetric practice. Our objective was to explore contributing factors to the increasing rate of cesarean delivery by examining the incidence of and indications for cesarean delivery over the past three decades at our institutions. MATERIAL AND METHODS: We conducted a retrospective observational study of all cesarean deliveries, from 24 weeks' gestational age onwards, within an inner-city hospital network in Sydney, Australia, between August 1989 and December 2016. The primary outcome measures were the rates of and indications for emergency and planned cesarean delivery. We also examined our data within the Robson 10-Group Classification system. RESULTS: There were 147 722 births over the study period, with 37 309 cesarean deliveries for an overall rate of 25.3%. The rate of cesarean delivery increased from 18.7% in 1989-1994 (8.7% emergency, 10% planned) to 30.4% in 2010-2016 (11.4% emergency, 19% planned). Emergency cesarean delivery for slow progress increased from 3.4% to 5.5% of all births (a relative increase of 62%) and other emergency cesareans mainly performed for suspected intrapartum fetal compromise increased from 5.2% to 5.6% (a relative increase of 8%). Previous uterine surgery (predominantly cesarean section) was the largest contributor to the increase in planned procedures from 3.8% to 9.0% of all births, and 29% of all cesarean deliveries. Primary cesarean delivery for planned antenatal fetal indications, previous pregnancy problems, multiple gestation and maternal choice all increased substantially in combined rate from 0.7% to 4.9%. Cesarean rates in Robson groups 6, 7 and 8 (term breech and multiple gestations) increased most over time. CONCLUSIONS: The increased rate of cesarean delivery is mainly attributable to a greater number of procedures performed for slow progress in labor, breech presentation or repeat cesarean section.

Outcomes following acute tocolysis prior to emergency caesarean section.

AIM: To determine if a policy recommending administration of terbutaline prior to emergency caesarean section improved arterial umbilical cord pH. MATERIALS AND METHODS: This was a prospective audit between February 2018 and June 2019 among women who underwent a category one or two caesarean section. Neonatal cord gas results and perinatal outcomes were compared before and after the introduction of a policy recommending subcutaneous terbutaline prior to emergency caesarean section. RESULTS: Among 423 women in the pre-policy change cohort and 253 post-policy change, there was no difference in arterial cord pH (median pH = 7.24 before the policy and median pH = 7.24 after the policy was introduced, P = 0.88). There was no statistically significant difference in any perinatal outcome, apart from the median arterial cord lactate which was higher in the post-treatment group (4.2 mmol/L vs 3.9 mmol/L, P = 0.006). Maternal heart rate was higher (median 110 vs 95, P < 0.0001) in the post-treatment group. Breastfeeding was more common in the post-treatment group (99% vs 95%, P = 0.005). There was no difference in estimated blood loss or rate of post-partum haemorrhage. A post hoc analysis according to treatment received, limited to caesarean section when the indication was suspected fetal compromise, demonstrated that among women who received terbutaline the rate of low pH (<7.1) was 3.8% (5/130) when terbutaline was given, compared with 6.6% (18/272) when terbutaline was not given (χ21  = 1.3, P = 0.26). CONCLUSION: Changing our labour ward policy to recommending terbutaline prior to all category one and category two caesarean sections did not change arterial cord pH.

First-Trimester Prediction of Preterm Prelabour Rupture of Membranes.

BACKGROUND: Preterm prelabour rupture of membranes (PPRoM) is commonly associated with preterm delivery and affects up to 3% of all pregnancies. It is associated with high rates of morbidity and mortality for the mother and the newborn. OBJECTIVES: To identify risk factors for PPRoM and develop a model for first-trimester prediction of risk of PPRoM. METHODS: A retrospective analysis of a series of women who had first-trimester (11-13+6 weeks) screening for aneuploidy and pre-eclampsia and delivered in the same institution was performed. Univariate and multivariate logistic regression analyses were used to identify maternal and pregnancy factors and then develop a clinical prediction model for PPRoM. RESULTS: 10,280 women were screened between April 2010 and October 2016. 144 (1.4%) had PPRoM. Maternal factors predictive of PPRoM included nulliparity (parous women, OR 0.53; 95% CI 0.4-0.8), pre-existing diabetes mellitus (DM) (Type 1 DM, OR 6.7; 95% CI 2.3-19.4, Type 2 DM, OR 5.3; 95% CI 1.6-18.3), maternal age group (p = 0.004), and BMI category (p = 0.012). Uterine artery pulsatility index (UAPI) and biochemical parameters (PAPP-A, free ßHCG) did not reach statistical significance. The predictive model had moderate efficacy with an area under the ROC curve of 0.67. CONCLUSIONS: Several maternal characteristics collected during first-trimester screening predict PPRoM. Biomarkers currently measured during first-trimester screening (PAPP-A, ßHCG, and UAPI) do not predict PPRoM. Whilst a predictive model can be generated with information currently collected at 11-13+6 weeks, this has only modest screening performance. First-trimester screening provides a structured framework where other predictors could improve model performance, and future studies should focus on the addition of other risk factors and biomarkers that may improve screening efficacy.

Uterine Artery Pulsatility Index Assessment at <11 Weeks' Gestation: A Prospective Study.

OBJECTIVE: Mean uterine artery pulsatility index (meanUAPI) is commonly measured at 11-13+6 weeks to predict adverse pregnancy outcomes including hypertensive disorders and small-for-gestational age. The aims of this study were to establish a population-specific reference range for meanUAPI at <11 weeks, to determine if an abnormal meanUAPI at <11 weeks was associated with adverse pregnancy outcome, and to assess changes in meanUAPI between <11 weeks and 11-13+6 weeks. METHODS: A prospective cohort was examined at <11 weeks and at 11-13+6 weeks to develop reference ranges for meanUAPI. Based on these regression models, meanUAPI Z-scores were compared between outcome groups using a two-sample t test. Longitudinal changes in the meanUAPI between <11 and 11-13+6 weeks were assessed by two-way mixed ANOVA. RESULTS: Prior to 11 weeks, there was no significant difference in meanUAPI between normal (n = 622) and adverse (n = 80) outcomes (mean [95% CI]: 2.62 [2.57-2.67] and 2.67 [2.50-2.84], respectively; p = 0.807). At 11-13+6 weeks, meanUAPI was significantly higher in the adverse (n = 66) compared with the normal (n = 535) outcome group (mean [95% CI]: 1.87 [1.70-2.03] and 1.67 [1.63-1.72], respectively; p = 0.040). There was a statistically significant decrease (p < 0.0001) in meanUAPI between the two time points. CONCLUSION: MeanUAPI measured at <11 weeks' gestation does not appear to be a useful marker for the prediction of placental-related adverse pregnancy outcomes, supporting an argument for the prediction of risk at 11-13+6 weeks' gestation.

Fetal biometry for guiding the medical management of women with gestational diabetes mellitus for improving maternal and perinatal health.

BACKGROUND: Gestational diabetes mellitus (GDM) is a common medical condition that complicates pregnancy and causes adverse maternal and fetal outcomes. At present, most treatment strategies focus on normalisation of maternal blood glucose values with use of diet, lifestyle modification, exercise, oral anti-hyperglycaemics and insulin. This has been shown to reduce the incidence of adverse outcomes, such as birth trauma and macrosomia. However, this involves intensive monitoring and treatment of all women with GDM. We propose that using medical imaging to identify pregnancies displaying signs of being affected by GDM could help to target management, allowing low-risk women to be spared excessive intervention, and facilitating better resource allocation. OBJECTIVES: We wanted to address the following question: in women with gestational diabetes, does the use of fetal imaging plus maternal blood glucose concentration to indicate the need for medical management compared with glucose concentration alone reduce the risk of adverse perinatal outcomes? SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth's Trials Register (29 January 2019), ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP) (both on 29 January 2019), and reference lists of retrieved studies. SELECTION CRITERIA: Randomised controlled trials, including those published in abstract form only. Studies using a cluster-randomised design and quasi-randomised controlled trials were both eligible for inclusion, but we didn't identify any. Cross-over trials were not eligible for inclusion in our review.We included women carrying singleton pregnancies who were diagnosed with GDM, as defined by the trials' authors. The intervention of interest was the use of fetal biometry on imaging methods in addition to maternal glycaemic values for indicating the use of medical therapy for GDM. The control group was the use of maternal glycaemic values alone for indicating the use of such therapy. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and assessed risk of bias. Two review authors extracted data and checked them for accuracy. MAIN RESULTS: Three randomised controlled trials met the inclusion criteria for our systematic review - the studies randomised a total of 524 women.We assessed the three included studies as being at a low to moderate risk of bias; the nature of the intervention made it difficult to achieve blinding of participants and personnel and none of the trial reports contained information about methods of allocation concealment (and were therefore assessed as being at an unclear risk of selection bias).In all studies, the intervention was the use of fetal biometry on ultrasound to identify fetuses displaying signs of fetal macrosomia, and the use of this information to indicate the use of medical anti-hyperglycaemic treatments. Those pregnancies were subject to more stringent blood glucose targets than those without signs of fetal macrosomia.Maternal outcomesThe use of fetal biometry in addition to maternal blood glucose concentration (compared with maternal blood glucose concentration alone) may make little or no difference to the incidence of caesarean delivery (risk ratio (RR) 0.81, 95% confidence interval (CI) 0.59 to 1.10; 2 trials, 428 women; low-certainty evidence). We are unclear about the results for hypertensive disorders of pregnancy (RR 0.80, 95% CI 0.34 to 1.89; 2 trials, 325 women) due to very low-certainty evidence. The included trials did not report on development of type 2 diabetes in the mother or maternal hypoglycaemia.Fetal and neonatal outcomesThe use of fetal biometry may make little or no difference to the incidence of neonatal hypoglycaemia (RR 0.90, 95% CI 0.57 to 1.42; 3 trials, 524 women; low-certainty evidence). Very low-certainty evidence means that we are unclear about the results for large-for-gestational age (RR 0.81, 95% CI 0.38 to 1.74; 3 trials, 524 women); shoulder dystocia (RR 0.33, 95% CI 0.01 to 7.98; 1 trial, 96 women); a composite measure of perinatal morbidity or mortality (RR 1.00, 95% CI 0.21 to 4.71; 1 study, 96 women); or perinatal mortality (RR 0.33, 95% CI 0.01 to 7.98; 1 trial, 96 women). AUTHORS' CONCLUSIONS: This review is based on evidence from three trials involving 524 women. The trials did not report some important outcomes of interest to this review, and the majority of our secondary outcomes were also unreported. The available evidence ranged from low- to very low-certainty, with downgrading decisions based on limitations in study design, imprecision and inconsistency.There is insufficient evidence to evaluate the use of fetal biometry (in addition to maternal blood glucose concentration values) to assist in guiding the medical management of GDM, on either maternal or perinatal health outcomes, or the associated costs.More research is required, ideally larger randomised studies which report the maternal and infant short- and long-term outcomes listed in this review, as well as those outcomes relating to financial and resource implications.

First-trimester ultrasound features associated with subsequent miscarriage: A prospective study.

BACKGROUND: First-trimester miscarriage is common, with women increasingly offered an ultrasound scan early in the first trimester to assess the status of their pregnancy. Ultrasound is uniquely situated to significantly impact the clinical management of these women. AIMS: This study aims to determine whether there were any differences in the early ultrasound appearances of pregnancies that continued to be viable or resulted in miscarriage before 12 weeks gestation. MATERIALS AND METHODS: This was a prospective cohort study including ultrasound measurements: mean sac diameter (MSD), yolk sac diameter (YSD), crown-rump length (CRL), fetal heart rate (FHR), trophoblast thickness, trophoblast volume (TTV) and mean uterine artery pulsatility index (meanUAPI). Regression models were fitted for each parameter and Z-scores compared between cohorts that progressed or miscarried after the scan but before 12 weeks gestation. Logistic regression analysis was used to create a prediction model for miscarriage prior to 12 weeks gestation based on the standardised ultrasound measurements recorded during the early first-trimester scan. RESULTS: Comparison of Z-Scores for meanUAPI, TTV, FHR and MSD demonstrated significant variation between the two groups. The proposed logistic regression model resulted in an area under the receiver operator curve of 0.81. At a false-positive rate of 30%, the model resulted in a sensitivity of 76% (95% CI 64-89%). CONCLUSION: The combination of FHR, meanUAPI, TTV in a prediction model for miscarriage may prove to be of value for ongoing pregnancy management in the first trimester.

The association between induction of labour at 38 to 39 weeks pregnancy and indication for caesarean delivery: An observational study.

BACKGROUND: Induction of labour is associated with a reduction in caesarean delivery, but the mechanism of action and which groups of women might benefit remain unknown. AIMS: To assess the association between induction of labour at 38-39 weeks pregnancy, and caesarean delivery: (i) overall; (ii) for slow progress in labour; and (iii) for suspected fetal compromise. MATERIAL AND METHODS: Retrospective observational study in two Sydney hospitals from 2009 to 2016, among nulliparous women with induction of labour at 38 or 39 completed weeks pregnancy and a singleton, cephalic presenting fetus. The comparator was all planned vaginal births beyond 39(+1/7) weeks, whether or not labour was induced. Binary and multinomial multiple logistic regressions adjusting for multiple confounders were performed. RESULTS: There were 2388 and 15 259 women in the study and comparison groups respectively. Induction of labour was associated with caesarean delivery overall only for women <25 years of age (adjusted odds ratio 1.63; 95% CI 1.17-2.27) and was not associated with caesarean delivery for slow progress. Induction of labour was positively associated with increased caesarean delivery for suspected fetal compromise among young women (<30 years), with the association weakening as maternal age increased. The association between induction of labour and caesarean delivery was different for slow progress compared with suspected compromise (P = 0.005). CONCLUSIONS: Induction of labour has different effects on the likelihood of caesarean delivery for slow progress and for suspected fetal compromise. Women <30 years of age are at higher risk of caesarean delivery for suspected fetal compromise, potentially due to uterine hyperstimulation.

Outcomes of induction of labour in nulliparous women at 38 to 39 weeks pregnancy by clinical indication: An observational study.

BACKGROUND: Knowledge of the outcomes of induction of labour for different indications is sparse. AIMS: To describe the mode of birth and other outcomes for nulliparous women induced at 38-39 weeks gestational age by indication for induction of labour. MATERIAL AND METHODS: This was a retrospective observational study in a tertiary referral hospital, and a metropolitan teaching hospital in Sydney. The study population was nulliparous women with induction of labour at 38 or 39 completed weeks of pregnancy and a singleton, cephalic presenting baby planning a vaginal birth, from 2009 to 2016. The indication for induction of labour was classified into 12 groups. Mode of birth and other maternal and perinatal outcomes were described in each group, for women who spontaneously laboured at 38 or 39 weeks, and for women who gave birth from 40 completed weeks onward. The main outcome measure was mode of birth. RESULTS: There were 3330 women with induction of labour at 38 or 39 weeks gestation. Rates of vaginal birth varied widely, ranging from 54% when the indication for induction was suspected large fetus, to 82% when the indication was suspected fetal compromise, and was 74% overall. Indications for caesarean delivery also varied by indication for induction. Among women giving birth ≥40 weeks gestational age, 75% had a vaginal birth. CONCLUSIONS: In nulliparous women, rates of vaginal birth following induction of labour at 38 or 39 weeks gestation vary widely according to the indication for induction. These data are useful for antenatal counselling.

Population attributable fractions of perinatal outcomes for nulliparous women associated with overweight and obesity, 1990-2014.

OBJECTIVE: To examine the prevalence across 25 years of overweight and obesity among nulliparous Australian women during early pregnancy; to estimate the proportions of adverse perinatal outcomes attributable to overweight and obesity in this population. DESIGN: Cohort study; retrospective analysis of electronic maternity data. Setting, participants: 42 582 nulliparous women with singleton pregnancies giving birth at the Royal Prince Alfred Hospital, an urban teaching hospital in Sydney, January 1990 - December 2014. MAIN OUTCOME MEASURES: Maternal body mass index (BMI), socio-demographic characteristics, and selected maternal, birth and neonatal outcomes; the proportion of adverse perinatal outcomes that could be averted by reducing the prevalence of overweight and obesity in women prior to first pregnancies (population attributable fraction, PAF). RESULTS: The prevalence of overweight among nulliparous pregnant women increased from 12.7% (1990-1994) to 16.4% (2010-2014); the prevalence of obesity rose from 4.8% to 7.3% in the same period, while the proportion with normal range BMIs fell from 73.5% to 68.2%. The PAFs for key adverse maternal and neonatal outcomes increased across the study period; during 2010-2014, 23.8% of pre-eclampsia, 23.4% of fetal macrosomia, and 17.0% of gestational diabetes were attributable to overweight and obesity. Were overweight and obese women to have moved down one BMI category during 2010-2014, 19% of pre-eclampsia, 15.9% of macrosomia, 14.2% of gestational diabetes, 8.5% of caesarean deliveries, 7.1% of low for gestational age birthweight, 6.8% of post partum haemorrhage, 6.5% of admissions to special care nursery, 5.8% of prematurity, and 3.8% of fetal abnormality could have been averted. CONCLUSIONS: Over the past 25 years, the proportions of adverse perinatal outcomes attributable to overweight and obesity have risen with the increasing prevalence of maternal overweight and obesity. A substantial proportion of these outcomes might be averted with obesity prevention strategies that reduce pre-pregnancy maternal weight.

Is sonographically measured cervical length at 37 weeks of gestation associated with intrapartum cesarean section? A prospective cohort study.

INTRODUCTION: Cesarean section rates continue to increase globally. Prediction of intrapartum cesarean section could lead to preventive measures. Our aim was to assess the association between sonographically measured cervical length at 37 weeks of gestation and cesarean section among women planning a vaginal birth. The population was women with a low-risk pregnancy or with gestational diabetes. MATERIAL AND METHODS: This was a prospective cohort study conducted in a tertiary referral hospital in Sydney, Australia. In all, 212 women with a low-risk pregnancy or with gestational diabetes were recruited including 158 nulliparous and 54 parous women. Maternal demographic, clinical and ultrasound characteristics were collected at 37 weeks of gestation. Semi-Bayesian logistic regression and Markov chain Monte Carlo simulation were used to assess the relation between cervical length and cesarean section in labor. RESULTS: Rates of cesarean section were 5% (2/55) for cervical length ≤20 mm, 17% (17/101) for cervical length 20-32 mm, and 27% (13/56) for cervical length >32 mm. These rates were 4, 22 and 33%, respectively, in nulliparous women. In the semi-Bayesian analysis, the odds ratio for cesarean section was 6.2 (95% confidence interval 2.2-43) for cervical length 20-32 mm and 10 (95% confidence interval 4.8-74) for cervical length >32 mm compared with the lowest quartile of cervical length, after adjusting for maternal age, parity, height, prepregnancy body mass index, gestational diabetes, induction of labor, neonatal sex and birthweight centile. CONCLUSIONS: Cervical length at 37 weeks of gestation is associated with intrapartum cesarean section.

Does previous caesarean section at full dilatation increase the likelihood of subsequent spontaneous preterm birth?

BACKGROUND: There is emerging evidence that caesarean section at full dilatation is associated with an increased risk of subsequent spontaneous preterm birth. AIM: To investigate the association between caesarean section at full dilatation and spontaneous preterm birth in subsequent pregnancies. MATERIALS AND METHODS: This was a retrospective cohort study of women who had two consecutive births at Royal Prince Alfred Hospital, 1989-2015. Our main comparison group was women who had emergency caesarean sections during the first stage of labour. Secondary comparison groups were women who had elective caesarean sections, instrumental deliveries and unassisted vaginal deliveries. The primary outcome was spontaneous preterm birth (<37 weeks gestation) in a subsequent pregnancy. RESULTS: There were 2672 women who had an emergency caesarean section, with 2142 (80%) performed during the first stage of labour and 533 (20%) at full dilatation. The rates of spontaneous preterm birth in a subsequent pregnancy were 1.7% and 3.8%, respectively (odds ratio 2.2 (95%CI 1.3-3.8), P = 0.003). The hazard ratio for spontaneous onset of labour at any given gestation from 20 weeks until full term was 1.4 (95%CI 1.2-1.6) and did not change after adjusting for maternal age and body mass index. CONCLUSION: There is a significantly higher rate of subsequent spontaneous preterm birth in women who had a caesarean section at full dilatation compared with women who had a caesarean section during the first stage of labour. Awareness of this as a risk factor may warrant referral to a high-risk obstetric or preterm birth clinic.

Medical management of miscarriage: Predictive factors of success.

Medical management of miscarriage is an acceptable option available to women, and has advantages of providing timely treatment, while avoiding exposure to surgery and anaesthesia. This retrospective cohort study aimed to determine factors predictive of successful medical management, utilising a single dose protocol of 800 µg vaginal misoprostol. In this cohort, the success rate was 67% (199/296), and smaller mean gestational sac diameter independent of gestational age predicted success (P = 0.046). Success is not significantly related to parity, miscarriage type, pelvic pain or vaginal bleeding at the outset of treatment.

Is ultrasound measured fetal biometry predictive of intrapartum caesarean section for failure to progress?

BACKGROUND: There are global concerns regarding excessive caesarean rates, which could be reduced by identification of risk factors leading to preventative measures such as induction of labour. AIMS: This study aims to describe the association between antenatal ultrasound and emergency caesarean section for: (i) failure to progress; (ii) other indications; and (iii) any indication. MATERIALS AND METHODS: Women who had an ultrasound in pregnancy between 36(+0/7) to 38(+6/7) weeks at Royal Prince Alfred Hospital from January 2005 to June 2009 were included. Ultrasound parameters were linked to clinical parameters from the maternity database. Missing clinical data were imputed and multiple logistic regression performed. RESULTS: Fetal biometry data were available for 2006 pregnancies. After adjusting for maternal age, height, body mass index, parity, previous caesarean section and diabetes, caesarean section for failure to progress was associated with estimated fetal weight (odds ratio (OR) 2.24 (95% CI: 1.76-2.84) per 500 g increase); or biparietal diameter (OR 1.51 (1.16-1.97) per 5 mm increase) and abdominal circumference (OR for the 4th quartile (>75th centile) compared with the 10-25th centile group was 2.09 (1.13-3.85)).* There were also non-linear associations between components of fetal biometry and caesarean section for fetal distress and for any indication. CONCLUSIONS: Components of fetal biometry in the third trimester are associated with intrapartum caesarean section for failure to progress. These parameters could be incorporated into models to predict emergency caesarean section which could lead to implementation of preventative strategies. *[Corrections added on 29 January 2018, after first online publication, '(OR for the 4th quartile (>7th centile)' has been changed to '(OR for the 4th quartile (>75th centile)'.].