Management plan for breech presentation

This search identified an existing UK-based guideline from the Royal College of Obstetricians and Gynaecologists (RCOG), Management of Breech Presentation (Green-top Guideline No. 20a).¹³ In brief, women who do not have a contraindication to ECV are offered this procedure (turning of the fetus by manual manipulation without anaesthetic). Where the procedure is contraindicated, declined or unsuccessful women would then have a discussion regarding attempting vaginal breech birth. Where vaginal breech birth was contraindicated or declined, a planned caesarean section would be scheduled at 39 weeks’ gestation (in the absence of a clinical indication for earlier delivery) with the proviso that the infant would be delivered by emergency caesarean section if the woman presented in labour before the scheduled date. Women who had a successful ECV would have routine care thereafter, but with midwife checks to ensure that the infant had not reverted to breech. In practice, given that the target population is nulliparous, it would be a small minority who would opt for vaginal breech birth and no women took up this option in the POP study.¹¹ For the purposes of the Markov chain modelling and health economic analysis we used the effect estimates of a Cochrane review that quantified ‘the effects of planned Caesarean section for singleton breech presentation at term on measures of pregnancy outcome’.¹⁴ Other parameters were obtained from the literature and are detailed in Chapter 11.

Management plan for diagnosis of a small for gestational age fetus

We next used the NICE evidence search engine to identify existing guidelines for the management of a SGA fetus. This search identified an existing UK-based guideline from the RCOG, The Investigation and Management of the Small-for-Gestational-Age Fetus, Investigation and Management (Green-top Guideline No. 31).¹⁵² Much of this guideline focuses on the identification of risk factors in early pregnancy and the management of the preterm SGA fetus. The RCOG recommendations are: (1) to take into consideration and abnormal umbillical artery or MCA Doppler to time delivery, (2) to offer delivery of the SGA fetus at 37 weeks’ gestation even if the umbilical artery Doppler is normal, (3) to recommend caesarean section in the SGA fetus with umbilical artery AREDV and (4) to offer IOL and continuous fetal heart monitoring in the SGA fetus with normal umbilical artery Doppler or with abnormal umbilical artery PI but end–diastolic velocities present.

The same search also identified an NHS England care bundle that aimed to reduce rates of perinatal death, Saving Babies’ Lives Version Two: A Care Bundle for Reducing Perinatal Mortality.¹⁵³ This guideline has a section on the management of SGA fetuses at term, and the following are key recommendations: (1) in the cases of severe SGA < 3rd centile and with no other concerning features, delivery should be offered at 37⁺⁰ weeks’ gestation and no later than 37⁺⁶ weeks’ gestation. (2) Fetuses between the 3rd and 10th centile should be assessed individually and the risk assessment should include Doppler investigations, the presence of any other high-risk features, for example, recurrent reduced fetal movements. In the absence of any high-risk features IOL should be offered at 39⁺⁰ weeks.

However, the context for both the RCOG and the NHS England guidelines was the management of women who were identified through the current approach of targeting ultrasound to high-risk women. As outlined in Chapter 9, we have not found evidence that these additional ultrasound tests are diagnostically effective when used as screening tests. Hence, the management protocol for SGA infants employed in the health economic analysis is to offer IOL. For the purposes of the health economic analysis we used the effect estimates of a Cochrane review that quantified ‘the effects of immediate delivery versus expectant management of the term suspected compromised infant on neonatal, maternal and long-term outcomes’.¹⁵⁰ In practice, 90% of the women included in the review came from a trial of IOL for suspected FGR.⁹⁹ IOL took place in the intervention group of this trial at an average of 38 weeks’ gestation and we have incorporated this into our management protocol (see section below). This does not represent an extreme intervention as a large-scale NIH-funded RCT demonstrated no adverse effect of routine IOL at 39 weeks’ gestation in nulliparous women who did not have risk factors.¹⁵⁴ Other parameters were obtained from the observational literature and are detailed in Chapter 11.

Management plan following diagnosis of a large for gestational age fetus

We next used the NICE evidence search engine to identify existing guidelines for the management of a LGA fetus. The only guidelines that we identified using this search related to women with diabetes. These women are routinely scanned during pregnancy and have specific issues, and the recommendations for this group are not generalisable to the population of interest in the current report. However, the search did identify a number of systematic reviews that addressed IOL, and one of these was a Cochrane review.¹⁵¹ The Cochrane review concluded that IOL for suspected fetal macrosomia results in a lower mean birthweight, fewer birth fractures and shoulder dystocia. They concluded that to prevent one fracture it would be necessary to induce labour in 60 women and that induction of labour does not appear to alter the rate of caesarean delivery or instrumental delivery. However they suggested that further trials of induction shortly before term for suspected fetal macrosomia are needed.¹⁵¹

Consistent with this recommendation, the HTA programme has funded a RCT [‘Induction of labour for predicted macrosomia: the Big Baby trial’ (ISRCTN18229892)]. Given the uncertainty in the evidence base, it is not possible to develop a robust plan for management following a diagnosis of macrosomia. For the purposes of the Markov chain modelling and health economic analysis, we addressed this uncertainty by comparing multiple strategies, including expectant management, early-term IOL and planned caesarean section. The effects in relation to IOL were taken from the Cochrane review,¹⁵¹ as this was assessed as the highest-quality evidence available at the time of writing. About 70% of the women came from a single trial¹⁰¹ in which the most common week for IOL was 38 weeks’ gestation. Other parameters for the modelling and health economic analysis were obtained from the observational literature and are detailed in Chapter 11. A summary of the management plan is outlined in Figure 11.

FIGURE 11

Summary of the management plan following the 36 weeks’ gestation scan.