A stochastic model for early placental development

In the human, placental structure is closely related to placental function and consequent pregnancy outcome. Studies have noted abnormal placental shape in small-for-gestational age infants which extends to increased lifetime risk of cardiovascular disease. The origins and determinants of placental shape are incompletely under-stood and are difficult to study in vivo. In this paper we model the early development of the placenta in the human, based on the hypothesis that this is driven by dynamics dominated by a chemo-attractant effect emanating from proximal spiral arteries in the decidua. We derive and explore a two-dimensional stochastic model for these events, and investigate the effects of loss of spiral arteries in regions near to the cord insertion on the shape of the placenta. This model demonstrates that placental shape is highly variable and disruption of spiral arteries can exert profound effects on placental shape, particularly if this disruption is close to the cord insertion. Thus, placental shape reflects the underlying maternal vascular bed. Abnormal placental shape may reflect an abnormal uterine environment, which predisposes to pregnancy complications

Improved Management of Stillbirth using a Care Pathway.

PurposeEach year approximately 3,200 women have a stillbirth in the UK. Although national evidence-based guidance has existed since 2010, case reviews continue to identify suboptimal clinical care and communication with parents. Inconsistencies in management include induction and management of labour and the frequency of investigation after stillbirth. The paper aims to discuss these issues.Design/methodology/approachAn audit of stillbirths was performed in 2014 in 13 maternity units in the North West of England, this confirmed variation in practice described nationally. An integrated care pathway (ICP) was developed from national guidelines to enable optimal care for the management of stillbirth, reduce variation, standardise investigations and coordinate patient-focussed care. This was launched in 2015 and updated in 2016 to resolve the issues that were apparent after implementation.FindingsEach participating unit had commenced using the ICP by May 2015. Following implementation there were changes in care, most notably from diverse methods for the induction of labour to guideline-directed induction of labour. There were trends towards better care in terms of information given, choices offered, more appropriate analgesia in labour and improved post-delivery investigation for cause. Staff feedback about the ICP was positive.Practical implicationsThe use of this ICP improved care for women who had a stillbirth and their families. Issues with implementing a changed care pathway meant that further iterations were required, ongoing improvement is expected following the refinement of the ICP.Originality/valueICPs have been used for various clinical conditions. However, this is the first example of their use in women who had a stillbirth

Comparing placentas from normal and abnormal pregnancies

This report describes work carried out at a Mathematics-in-Medicine Study Group. It is believed that placenta shape villous network characteristics are strongly linked to the placenta’s efficiency, and hence to pregnancy outcome. We were asked to consider mathematical ways to describe the shape and other characteristics of a placenta, as well as forming mathematical models for placenta development. In this report we propose a number of possible measure of placental shape, form, and efficiency, which can be computed from images already obtained. We also consider various models for the early development of placentas and the growth of the villous tree

Stillbirth and intrauterine fetal death:role of routine histopathological placental findings to determine cause of death

OBJECTIVES: Placental abnormalities are a common cause of death in stillbirth, ranking second only to unexplained deaths, though there is wide variation in the proportion attributed to placental disease. In clinical practice, interpretation of the significance of placental findings is difficult, since many placental features in stillbirths overlap with those in live births. Our aim was to examine objectively classified placental findings from a series of > 1000 autopsies following intrauterine death in order to evaluate the role of placental histological examination in determining the cause of death. METHODS: As part of a larger study evaluating several aspects of autopsy findings in intrauterine death, a dedicated database was used to collate antenatal and postmortem examination details for all cases examined between 2005 and 2013 at two tertiary specialist centers in London, UK. Histological findings for placentas were evaluated in relation to the final cause of death. RESULTS: Among 1064 intrauterine deaths, 946 (89%) cases had the placenta submitted for examination as part of the autopsy. Of these, 307 (32%) cases had the cause of death assigned to abnormalities of the placenta, cord or membranes. Around one third of stillbirths (≥ 24 weeks) had some isolated placental histological abnormality identified, many of uncertain significance, a significantly greater proportion than in cases of second-trimester intrauterine fetal demise (P < 0.0001). The cause of death was ascending infection in 176/946 (19%) cases, peaking at 22 weeks' gestation, with significantly more black mothers having ascending infection compared with other ethnicities (P < 0.0001). Maternal vascular malperfusion was the largest category of placental abnormalities in stillbirth, with peak prevalence in the early third trimester. There were 18 (2%) cases with specific histological abnormalities, including chronic histiocytic intervillositis and massive perivillous fibrin deposition. CONCLUSIONS: Placental pathologies represent the largest category of cause of intrauterine death. Placental histological examination is the single most useful component of the autopsy process in this clinical setting. A minority of cases are associated with specific placental pathologies, often with high recurrence rates, that can be diagnosed only on microscopic examination of the placenta. Many deaths remain unexplained, although placental histological lesions may be present which are of uncertain significance. A rigorous, systematic approach to placental pathology research and classification may yield better understanding of the significance of placental findings and reduce the rate of unexplained intrauterine deaths

Stillbirth and intrauterine fetal death:contemporary demographic features of &gt;1000 cases from an urban population

OBJECTIVES: Of 780 000 births annually in the UK, around 3300 are stillborn, a rate of approximately 4 per 1000 births. Traditional epidemiological associations are based on historic data. The aim of this study was to document contemporary demographic findings in a large series of > 1000 deaths in utero in London and compare these with national datasets. METHODS: From a dedicated database, including > 400 data fields per case, of fetal, infant and pediatric autopsies performed at Great Ormond Street Hospital and St George's Hospital, London, we extracted information on all intrauterine deaths, excluding terminations of pregnancy, from 2005 to 2013, inclusive. Demographic data were analyzed according to the gestational age at which fetal death occurred (second-trimester intrauterine fetal death (IUFD), subdivided into early (1000 autopsies in cases of intrauterine death, these data highlight the increased risk for fetal loss associated with maternal demographic factors in contemporary clinical practice, particularly associations with increased maternal age and body mass index. Among women in whom an intrauterine death occurs, maternal ethnicity, mode of conception and gynecological history are associated with differing timing of fetal loss. Further research is required to understand the mechanisms involved in such maternal factors in order to develop preventative strategies

Predictors of Poor Perinatal Outcome following Maternal Perception of Reduced Fetal Movements: A Prospective Cohort Study

Background Maternal perception of reduced fetal movement (RFM) is associated with increased risk of stillbirth and fetal growth restriction (FGR). RFM is thought to represent fetal compensation to conserve energy due to insufficient oxygen and nutrient transfer resulting from placental insufficiency. Objective To identify predictors of poor perinatal outcome after maternal perception of reduced fetal movements (RFM). Design Prospective cohort study. Methods 305 women presenting with RFM after 28 weeks of gestation were recruited. Demographic factors and clinical history were recorded and ultrasound performed to assess fetal biometry, liquor volume and umbilical artery Doppler. A maternal serum sample was obtained for measurement of placentally-derived or modified proteins including: alpha fetoprotein (AFP), human chorionic gonadotrophin (hCG), human placental lactogen (hPL), ischaemia-modified albumin (IMA), pregnancy associated plasma protein A (PAPP-A) and progesterone. Factors related to poor perinatal outcome were determined by logistic regression. Results 22.1% of pregnancies ended in a poor perinatal outcome after RFM. The most common complication was small-for-gestational age infants. Pregnancy outcome after maternal perception of RFM was related to amount of fetal activity while being monitored, abnormal fetal heart rate trace, diastolic blood pressure, estimated fetal weight, liquor volume, serum hCG and hPL. Following multiple logistic regression abnormal fetal heart rate trace (Odds ratio 7.08, 95% Confidence Interval 1.31–38.18), (OR) diastolic blood pressure (OR 1.04 (95% CI 1.01–1.09), estimated fetal weight centile (OR 0.95, 95% CI 0.94–0.97) and log maternal serum hPL (OR 0.13, 95% CI 0.02–0.99) were independently related to pregnancy outcome. hPL was related to placental mass. Conclusion Poor perinatal outcome after maternal perception of RFM is closely related to factors which are connected to placental dysfunction. Novel tests of placental function and associated fetal response may provide improved means to detect fetuses at greatest risk of poor perinatal outcome after RFM

A randomised controlled trial comparing standard or intensive management of reduced fetal movements after 36 weeks gestation-a feasibility study

BACKGROUND: Women presenting with reduced fetal movements (RFM) in the third trimester are at increased risk of stillbirth or fetal growth restriction. These outcomes after RFM are related to smaller fetal size on ultrasound scan, oligohydramnios and lower human placental lactogen (hPL) in maternal serum. We performed this study to address whether a randomised controlled trial (RCT) of the management of RFM was feasible with regard to: i) maternal recruitment and retention ii) patient acceptability, iii) adherence to protocol. Additionally, we aimed to confirm the prevalence of poor perinatal outcomes defined as: stillbirth, birthweight <10(th) centile, umbilical arterial pH <7.1 or unexpected admission to the neonatal intensive care unit. METHODS: Women with RFM ≥36 weeks gestation were invited to participate in a RCT comparing standard management (ultrasound scan if indicated, induction of labour (IOL) based on consultant decision) with intensive management (ultrasound scan, maternal serum hPL, IOL if either result was abnormal). Anxiety was assessed by state-trait anxiety index (STAI) before and after investigations for RFM. Rates of protocol compliance and IOL for RFM were calculated. Participant views were assessed by questionnaires. RESULTS: 137 women were approached, 120 (88%) participated, 60 in each group, 2 women in the standard group did not complete the study. 20% of participants had a poor perinatal outcome. All women in the intensive group had ultrasound assessment of fetal size and liquor volume vs. 97% in the standard group. 50% of the intensive group had IOL for abnormal scan or low hPL after RFM vs. 26% of controls (p < 0.01). STAI reduced for all women after investigations, but this reduction was greater in the standard group (p = 0.02). Participants had positive views about their involvement in the study. CONCLUSION: An RCT of management of RFM is feasible with a low rate of attrition. Investigations decrease maternal anxiety. Participants in the intensive group were more likely to have IOL for RFM. Further work is required to determine the likely level of intervention in the standard care arm in multiple centres, to develop additional placental biomarkers and to confirm that the composite outcome is valid. TRIAL REGISTRATION: ISRCTN0794430

Breech presentation is associated with lower adolescent tibial bone strength

Summary We compared bone outcomes in adolescents with breech and cephalic presentation. Tibia bone mineral content, density, periosteal circumference, and cross-sectional moment of inertia were lower in breech presentation, and females with breech presentation had lower hip CSA. These findings suggest that prenatal loading may exert long-lasting influences on skeletal development. Introduction Breech position during pregnancy is associated with reduced range of fetal movement, and with lower limb joint stresses. Breech presentation at birth is associated with lower neonatal bone mineral content (BMC) and area, but it is unknown whether these associations persist into later life. Methods We examined associations between presentation at onset of labor, and tibia and hip bone outcomes at age 17 years in 1971 participants (1062 females) from a UK prospective birth cohort that recruited > 15,000 pregnant women in 1991–1992. Cortical BMC, cross-sectional area (CSA) and bone mineral density (BMD), periosteal circumference, and cross-sectional moment of inertia (CSMI) were measured by peripheral quantitative computed tomography (pQCT) at 50% tibia length. Total hip BMC, bone area, BMD, and CSMI were measured by dual-energy X-ray absorptiometry (DXA). Results In models adjusted for sex, age, maternal education, smoking, parity, and age, singleton/multiple births, breech presentation (n = 102) was associated with lower tibial cortical BMC (− 0.14SD, 95% CI − 0.29 to 0.00), CSA (− 0.12SD, − 0.26 to 0.02), BMD (− 0.16SD, − 0.31 to − 0.01), periosteal circumference (− 0.14SD, − 0.27 to − 0.01), and CSMI (− 0.11SD, − 0.24 to 0.01). In females only, breech presentation was associated with lower hip CSA (− 0.24SD, − 0.43 to 0.00) but not with other hip outcomes. Additional adjustment for potential mediators (delivery method, birthweight, gestational age, childhood motor competence and adolescent height and body composition) did not substantially affect associations with either tibia or hip outcomes. Conclusions These findings suggest that prenatal skeletal loading may exert long-lasting influences on skeletal size and strength but require replication

The carbon footprint of different modes of birth in the UK and the Netherlands: an exploratory study using life cycle assessment

Objective: To compare the carbon footprint of caesarean and vaginal birth. Design: Life cycle assessment (LCA). Setting: Tertiary maternity units and home births in the UK and the Netherlands. Population: Birthing women. Methods: A cradle-to-grave LCA using openLCA software to model the carbon footprint of different modes of delivery in the UK and the Netherlands. Main Outcome Measures: ‘Carbon footprint’ (in kgCO2 equivalents [kgCO2e]). Results: Excluding analgesia, the carbon footprint of a caesarean birth in the UK was 31.21 kgCO2e, compared with 12.47 kgCO2e for vaginal birth in hospital and 7.63 kgCO2e at home. In the Netherlands the carbon footprint of a caesarean was higher (32.96 kgCO2e), but lower for vaginal birth in hospital and home (10.74 and 6.27 kgCO2e, respectively). Emissions associated with analgesia for vaginal birth ranged from 0.08 kgCO2e (with opioid analgesia) to 237.33 kgCO2e (nitrous oxide with oxygen). Differences in analgesia use resulted in a lower average carbon footprint for vaginal birth in the Netherlands than the UK (11.64 versus 193.26 kgCO2e). Conclusion: The carbon footprint of a caesarean is higher than for a vaginal birth if analgesia is excluded, but this is very sensitive to the analgesia used; use of nitrous oxide with oxygen multiplies the carbon footprint of vaginal birth 25-fold. Alternative methods of pain relief or nitrous oxide destruction systems would lead to a substantial improvement in carbon footprint. Although clinical need and maternal choice are paramount, protocols should consider the environmental impact of different choices