Bradley de Vries

Does occiput posterior position in the second stage of labour increase the operative delivery rate

To assess the impact of occipito‐posterior position in the second stage of labour on operative delivery.

Persistent Occiput Posterior: OUTcomes following digital rotation: A pilot randomised controlled trial

To determine the feasibility of a multicentre randomised controlled trial (RCT) to investigate whether digital rotation of the fetal head from occiput posterior (OP) position in the second stage of labour reduces the risk of operative delivery (defined as caesarean section (CS) or instrumental delivery).

Management of occiput posterior position in the second stage of labour: A survey of obstetric practice in Australia and New Zealand

Issues in the management of the occipito posterior (OP) position have been the subject of clinical controversy over decades. Manual rotation has the potential to reduce operative delivery for fetal malposition.

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.

Transverse occiput position: Using manual Rotation to aid Normal birth and improve delivery OUTcomes (TURN-OUT): A study protocol for a randomised controlled trial.

BackgroundFetal occiput transverse position in the form of deep transverse arrest has long been associated with caesarean section and instrumental vaginal delivery. Occiput transverse position incidentally found in the second stage of labour is also associated with operative delivery in high risk cohorts. There is evidence from cohort studies that prophylactic manual rotation reduces the caesarean section rate. This is a protocol for a double blind, multicentre, randomised, controlled clinical trial to define whether this intervention decreases the operative delivery (caesarean section, forceps or vacuum delivery) rate.Methods/DesignEligible participants will be ≥37 weeks pregnant, with a singleton pregnancy, and a cephalic presentation in the occiput transverse position on transabdominal ultrasound early in the second stage of labour. Based on a background risk of operative delivery of 49%, for a reduction to 35%, an alpha value of 0.05 and a beta value of 0.2, 416 participants will need to be enrolled. Participants will be randomised to either prophylactic manual rotation or a sham procedure. The primary outcome will be operative delivery. Secondary outcomes will be caesarean section, significant maternal mortality and morbidity, and significant perinatal mortality and morbidity.Analysis will be on an intention-to-treat basis. Primary and secondary outcomes will be compared using a chi-squared test. A logistic regression for the primary outcome will be undertaken to account for potential confounders. This study has been approved by the Ethics Review Committee (RPAH Zone) of the Sydney Local Health District, Sydney, Australia, (protocol number: X110410).DiscussionThis trial addresses an important clinical question concerning a commonly used procedure which has the potential to reduce operative delivery and its associated complications. Some issues discussed in the protocol include methods of assessing risk of bias due to inadequate masking of a procedural interventions, variations in intervention efficacy due to operator experience and the recruitment difficulties associated with intrapartum studies.Trial registrationThis trial was registered with the Australian New Zealand Clinical Trials Registry (identifier: ACTRN12613000005752) on 4 January 2013.

Single‐dose methotrexate treatment for ectopic pregnancy and pregnancy of unknown location and progesterone as a predictor of success

The use of single‐dose intramuscular administration of methotrexate in the treatment of ectopic pregnancies (EP) is a well‐established practice. This study evaluates its use at a novel dose of 40 mg/m2 body surface area (BSA).

When should women be recruited to intrapartum research projects? A retrospective review

To review and describe the impact of varied recruitment processes in two intrapartum studies.

Is neonatal head circumference related to caesarean section for failure to progress

There is global concern about rising caesarean section rates. Identification of risk factors could lead to preventative measures.

A new approach to developing birth weight reference charts: a retrospective observational study

Introduction: Birth weight reference charts based on historical infant birth weights have significant bias at preterm gestations because many preterm births are associated with abnormal growth. This study aims to determine whether more accurate birth weight charts can be constructed using data only from births that follow spontaneous onset of labour. Materials and Methods: This study was a single-centre retrospective observational study of 115,712 singleton live births. Births were classified as spontaneous or iatrogenic. Quantile regression was used to model the relationship between gestational age, sex, labour onset, and birth weight. Comparison was made of birth weights in the spontaneous and iatrogenic cohorts by gestation, and to existing ultrasound-based charts. Results: Birth weights of spontaneous and iatrogenic births were significantly different for gestational age at the median and 10th centiles. Iatrogenic preterm infants weighed less than their spontaneous preterm counterparts. Median and 10th centile birth weights derived from the spontaneous birth cohort closely approximate previous ultrasound-based curves. Discussion: Iatrogenic births are more likely to be associated with pre-existing growth disturbance. Inclusion of these data has significant impact on centile charts. Birth weight charts derived from only spontaneous births may offer a more accurate reference for clinicians.

Transplacental haemorrhage may explain the intrapartum transmission of HIV. A pilot study uses flow cytometry to quantify maternal red blood cells in infants born vaginally or by caesarean section.

Intrapartum transmission is epidemiologically important for some viruses such as HIV and hepatitis B virus, but its precise mechanism is unknown. We hypothesised that the ability of elective caesarean section to prevent HIV may be due to prevention of transplacental microtransfusions of blood during labour. Their frequency is not known so we performed a pilot study which showed evidence of transplacental transfusion from mother to fetus in one of ten mother–infant pairs delivering vaginally and none of ten delivering by elective caesarean section. We conclude that transplacental transfusion occurs and is one possible mechanism for the intrapartum transmission of viruses from mother to baby.