Sarah Vause

Management of preterm labour

“The aetiology of preterm labour remains unknown, prediction lacks specificity, prophylaxis is unhelpful, diagnosis is difficult and the benefits and risks of tocolytic therapy are still being debated”1 The above quote testifies to the complexity of preterm labour, a process that ultimately results in considerable neonatal morbidity and mortality. It is difficult to quantify the incidence of spontaneous preterm labour, as many studies relating to preterm birth do not discriminate between spontaneous preterm labour and iatrogenic/therapeutic preterm delivery. The picture is further complicated as many studies report their results by birth weight rather than gestation. However, it has been estimated that the incidence of preterm delivery varies from 5% to 10% of all births in developed countries, and that spontaneous preterm labour in otherwise uncomplicated singleton pregnancies accounts for between one third and one half of all preterm deliveries.2 3 In 1997, in England and Wales, 50.3% of all neonatal deaths were due to immaturity.4 The costs of neonatal intensive care in the short term and the resources needed to support children with long term morbidity as a result of preterm birth are considerable. The underlying physiology and molecular biology of preterm labour is complex and not yet fully understood. A full discussion of the processes involved is outside the scope of this paper but is covered in a recent review article.5 The causes are also diverse and multifactorial. Figure 1 1 summarises some of the factors that may contribute to preterm labour. This paper will concentrate on the prediction, prevention, and treatment of preterm labour, and discuss the ways in which antenatal interventions can optimise the outcome for the fetus. Figure 1 Risk factors for preterm labour. ### CLINICAL RISK SCORING Preterm labour is more common in smokers, teenagers, drug abusers, women with bacterial vaginosis, multiple pregnancy, and women who have …

Factors relating to a rising incidence of major postpartum haemorrhage

Sir, We read with interest the paper by Audureau et al. We note that following their interventions (prophylactic syntocinon, blood-collecting bags and sulprostone) that the incidence of major postpartum haemorrhage (PPH) did not significantly alter (0.81% in 2003 and 0.86% in 2005). Unfortunately, in our unit, a tertiary referral unit delivering about 5200 women a year, we identified a rise in the rate of PPH from 0.39% in 2003 to 0.66% in 2005, and then to 1.22% in 2008. Our rates may be higher than those stated by Audureau et al., as our definition of major PPH was an estimated blood loss of ‡1500 ml. Audureau et al. defined major PPH as the presence of one or more of the following criteria: blood transfusion of at least one unit, surgery for uterine conservation, and hysterectomy. As suggested by Audureau et al., it may be that their interventions did not alter the incidence of PPH because of an underlying rise in PPH that was prevented, or contained, by the interventions. We have reviewed all of our cases of major PPH over a 6-year period (2003–2008) to identify possible reasons for the increased incidence. We were expecting that a rise in the caesarean section rate would be partly responsible. However, we demonstrated that in women with a major PPH the mode of delivery was by caesarean section in 59% of cases in 2003, 16% in 2005 and 18% in 2008. Audureau et al. noted an overall decreased rate of caesarean section in a random sample of all women, and that the rate did not change significantly in women with a major PPH. Therefore, contrary to popular belief, factors other than caesarean section appear to be responsible for the rise in PPH. We identified a rise in instrumental deliveries in women with a major PPH, and an increased proportion of PPH attributable to genital tract trauma. Another potential cause for the rise in PPH incidence may be the better estimation or overestimation of blood loss. One of the interventions introduced by Audureau et al. was the utilisation of blood-collecting bags. This may have led to a greater estimation of blood loss leading to more diagnoses of PPH. In our cases, the percentage of women transfused reduced from 94% in 2003 to 81% in 2005, and to 73% in 2008. In women that were not transfused, the percentage of women in whom the haemoglobin level dropped by greater than 3 g/dl reduced from 100% in 2004 to 50% in 2008. This would imply that there may be a greater estimation of blood loss now. The utilisation of interventions such as blood-collecting bags as suggested by Audureau et al. would be a useful adjunct to estimating blood loss more accurately. j Reference

Pregnancy outcomes in women with mechanical prosthetic heart valves: a prospective descriptive population based study using the United Kingdom Obstetric Surveillance System (UKOSS) data collection system

To describe the incidence of mechanical prosthetic heart valves (MPHV) in pregnancy in the UK; rates of maternal and fetal complications in this group of women, and whether these vary with the anticoagulation used during pregnancy.

Prospective comparative case study of uterine collagen in a woman with osteogenesis imperfecta type 1 who had previously ruptured her uterus.

A 23-year-old woman with osteogenesis imperfecta (OI) Type 1 presented at 14 weeks’ gestation, in her second pregnancy. She was 145 cm tall and had sustained fractures of the phalanges, radius and ulna during childhood. She had never fractured her pelvis or femora. She was known to have the COL1A1 mutation in keeping with her diagnosis of OI Type 1. The obstetric team remembered her well as she sustained an unprovoked uterine rupture of an unscarred uterus in her first pregnancy. She had presented in spontaneous labour at 6 cm dilatation with the fetal head 3 cm above the ischial spines. A plan had been made to aim for a vaginal delivery. She did not progress over 6 h and the fetal head remained high. She was not augmented with oxytocin, but was delivered by Caesarean section, at which time meconium, blood and liquor were found in the left broad ligament and a 3 cm rupture in the left lower segment of the uterus was noted. A live baby weighing 2.3 kg was delivered in good condition and the uterus was repaired. The obstetricians had postulated that the unprovoked uterine rupture was due to defective collagen in the uterus (Krishnamoorthy et al. 2002). Unfortunately, tissue was not taken at the time for histology, so there was no evidence to confirm or refute their idea. In view of the unprovoked uterine rupture in her first pregnancy, a plan was made that in this pregnancy, delivery should be by elective caesarean section. The patient and the obstetricians were keen to gain more information about the pathogenesis of the uterine rupture. The opportunity was taken to undertake a prospective comparative case study to determine whether the uterine collagen in this woman with OI Type 1 was different from a control. Consent wasobtained to take samples from her uterus at the time of her elective lower segment caesarean section (LSCS) for histological study. Samples from the uterus of a woman with a previous LSCS, who requested a repeat elective LSCS were also obtained, after appropriate consent was given, to be compared as control. Both patient and control were 39 weeks’ gestation. The operations were performed on consecutive days by the same surgeon. A 1 cm long, 0.5 cm wide biopsy was taken using the same technique from the lower edge of the uterine incision in each patient. The same pathologist performed standard histology and collagen stains on both samples in the same way. Picrosirius red was used to stain for Type 1 collagen and silver stains to stain for reticulin (Type III collagen) in the biopsies (Figures 1 and 2). In the uterine sample from the patient as compared with the control, there was:

Prophylaxis against infective endocarditis in obstetrics: new NICE guidance: a commentary

Summary Antibiotic prophylaxis is prescribed on labour wards in theUK for numerous risk factors and procedures, including pro-longed rupture of membranes, repair of third-degree tearsand during caesarean section. Current practice in the sub-stantial majority of UK units is to give antibiotic prophylaxisto women with cardiac lesions to prevent infective endocar-ditis. 6 NICEhasrecommendedasubstantialchangeinclinicalpracticebasedononepaperdescribingrates ofbacteraemia atcaesarean section. 8 NICE has suggested that antibiotic prophylaxis is unneces-sary because there is a lack of evidence to support its use.Absenceofevidencedoesnotequatetoabsenceofeffectivenesswhen the studies required have not been conducted. Indeed,this is the case for a substantial portion of obstetric manage-ment. The American Heart Association guidelines have takena more measured approach and recommended that womenwith high-risk cardiac conditions receive prophylaxis, asopposed to a blanket policy of no prophylaxis.

Management of women who are Rhesus D negative in Northern Ireland

In 1998, all 15 maternity hospitals in Northern Ireland participated in a retrospective survey of the management of pregnant women who were Rhesus D (RhD) negative. This area of clinical practice was chosen for study in the knowledge that a policy of routine antenatal prophylaxis had been proposed at the RCP/RCOG Consensus Conference, and that a change in current clinical practice was likely to follow. It was therefore felt prudent to survey critically current practice in order to collect baseline data before the introduction of new guidelines. Data were analysed on 3274 RhD negative women. The findings from this study show that current management of women who are RhD negative is suboptimal. In particular, there is poor adherence to the guidelines relating to the management of potentially sensitising events in pregnancy. Testing to assess the size of a feto-maternal bleed was often omitted, and it was therefore impossible to ascertain whether an appropriate dose of anti-D immunoglobulin had been administered. Recent publications have also identified this as an area of concern. Trauma during pregnancy was often not managed appropriately, as a potentially sensitising event. Better compliance with the current guidelines was noted when management after delivery was considered. The reasons for this apparent inconsistency should be addressed. New guidelines, recommending the use of routine antenatal prophylaxis to all women who are RhD negative, have recently been published. Providers of antenatal care will need to address this issue within the context of their own practice environment. In doing so they should be mindful of current deficits in guideline compliance which may need to be remedied, to avoid building new practices upon fragile foundations.In 1998, all 15 maternity hospitals in Northern Ireland participated in a retrospective survey of the management of pregnant women who were Rhesus D (RhD) negative. This area of clinical practice was chosen for study in the knowledge that a policy of routine antenatal prophylaxis had been proposed at the RCP/RCOG Consensus Conference, and that a change in current clinical practice was likely to follow. It was therefore felt prudent to survey critically current practice in order to collect baseline data before the introduction of new guidelines. Data were analysed on 3274 RhD negative women. The findings from this study show that current management of women who are RhD negative is suboptimal. In particular, there is poor adherence to the guidelines relating to the management of potentially sensitising events in pregnancy. Testing to assess the size of a feto-maternal bleed was often omitted, and it was therefore impossible to ascertain whether an appropriate dose of anti-D immunoglobulin had been administered. Recent publications have also identified this as an area of concern. Trauma during pregnancy was often not managed appropriately, as a potentially sensitising event. Better compliance with the current guidelines was noted when management after delivery was considered. The reasons for this apparent inconsistency should be addressed. New guidelines, recommending the use of routine antenatal prophylaxis to all women who are RhD negative, have recently been published. Providers of antenatal care will need to address this issue within the context of their own practice environment. In doing so they should be mindful of current deficits in guideline compliance which may need to be remedied, to avoid building new practices upon fragile foundations.

Maternal heart rate during the first 48 h postpartum: a retrospective cross sectional study

OBJECTIVES 1) Describe the distribution of heart rate in the first 48h postpartum in women with no evidence of sepsis, anaemia or haemorrhage. 2) Investigate the relationship between postpartum heart rate and other maternal factors. STUDY DESIGN A retrospective cross-sectional study of postpartum women who delivered between July 2012 and June 2015 in a tertiary hospital. Data was analysed from the local maternity system and electronic vital signs database. The main outcome measures: Heart rate at 6, 12, 24 and 48h postpartum. RESULTS Data were obtained on 11401 women. After exclusion of women with possible sepsis, anaemia or haemorrhage, 7627 heart rate readings from 5164 women were analysed. Mean heart rate (+2SD/+3SD) at 6h was 83.6 (108.2/120.6), 12h 84.5 (109.4/121.9), 24h 85.4 (110.4/122.9), and 48h 84.3 (109.7/122.4). There was statistical correlation of post partum heart rate with body mass index (BMI), age and discharge haemoglobin. CONCLUSION This study describes the distribution of maternal heart rate in the early postpartum period, in women with no evidence of sepsis, anaemia or major haemorrhage. This will facilitate identification and appropriate investigation of women with abnormal heart rates. Although correlation with BMI, age and discharge haemoglobin was demonstrated, the differences were small and not clinically meaningful. Further work investigating the relationship between postpartum heart rate and poor maternal outcomes is required.

Anhydramnios secondary to angiotensin II converting enzyme inhibitors: A reversible condition?

Increasing numbers of women are conceiving while taking angiotensin II converting enzyme inhibitors (ACEi). These are contraindicated in pregnancy due to fetotoxicity (Cooper 2008) resulting in craniosynostosis, oligohydramnios, fetal loss and neonatal renal failure (Smith 1989; Pryde et al. 1993; Rosenthal and Oparil 2002; Tabacova 2005; Boubred et al. 2006). We report a case of reversible ACEi-induced anhydramnios.

Anti-Xa based dose changes during low molecular weight heparin anticoagulation for mechanical prosthetic heart valves during pregnancy

Anticoagulation during pregnancy in women with mechanical prosthetic heart valves (MPHVs) is challenging. Maternal and foetal morbidity and mortality are high (MMBRACE-UK 2016). In the United Kingdom, 71% of women with MPHVs use low molecular weight heparin (LMWH) throughout pregnancy (Vause et al. 2016). Although concerns have been expressed as to whether LMWH is as effective an anticoagulant as warfarin, women may choose LMWH because of the reduced foetal risks. Guidelines are available regarding LMWH monitoring in pregnant women with MPHVs (Regitz-Zagrosek et al. 2011; American College of Chest Physicians 2012), although the evidence upon which the guidelines are based is not strong. The purpose of this study was to determine whether twice-daily LMWH monitored via anti-factor Xa (anti-Xa) levels is effective in providing sufficient anticoagulation.

Cardiovascular, obstetric and neonatal outcomes in women with previous fontan repair

OBJECTIVES To determine cardiovascular, obstetric and neonatal outcomes of pregnancies in women who have a Fontan circulation. METHODS A retrospective case note review of all women with a Fontan circulation who attended the joint obstetric cardiac antenatal clinic at St Marys Hospital, Manchester (UK) between 2004 and 2016 was performed. RESULTS In total, there were 19 pregnancies in 9 women with a history of Fontan repair. 23 women with univentricular physiology attended in this time period. 10 pregnancies (53%) resulted in live births; 1 in a stillbirth at 31 weeks gestation and 8 in miscarriage. Cardiovascular complications occurred in 2 pregnancies (11%). There were no thrombotic events, arrhythmias, myocardial infarction, or endocarditis in the antenatal or postnatal period. Obstetric complications included miscarriage (26% first trimester, 16% second trimester), along with premature delivery (24-36+6) (80%) and fetal growth restriction (70%). The majority of women were delivered by caesarean section (60%). CONCLUSIONS Women who become pregnant following a Fontan repair carry an increased risk of cardiovascular complications. Fetal and neonatal complication rates are high and emphasize the importance of thorough, multidisciplinary, pre-conceptual assessment and counseling to allow patients to make informed decisions regarding future pregnancy.