Rapid Midwifery E-Book

Sarah Snow

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Serie: Rapid
• Sprache: Englisch

Seitenzahl: 264

Veröffentlichungsjahr: 2016

Beschreibung

RAPID Midwifery

The Rapids are a series of reference and revision pocket books that cover key facts in a simple and memorable way. Each book contains the common conditions that students and newly qualified nurses encounter on the wards, in the community, and on placements. Only the basic core relevant facts are provided to ensure that these books are perfect and concise ‘rapid refreshers’. To see all the titles in the series, go to: www.wiley.com/go/rapids

Rapid Midwifery is an essential read for all midwifery students and newly qualified staff. Designed for quick reference, it explores a broad range of midwifery topics which are mapped against the 6Cs to illustrate the fundamental importance of compassionate midwifery care. Each section is structured around the key criteria used in midwifery examinations, with bite-sized information supported by the latest evidence base, making it the perfect revision tool for OSCEs and written examinations. Every chapter includes key points, essentials of midwifery care, key physiology, professional accountability, and links to further resources.

Covering all the key topics in midwifery, for both hospital and community settings, this concise and easy-to-read title is the perfect quick reference book.

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Leseprobe

Table of Contents

Cover

Title Page

Copyright

Preface

Acknowledgement

Part I: Antenatal Care

Antenatal Health Assessment

Anxiety and Depression

Bio-physical Tests

Bleeding in Pregnancy

Fetal Growth and Development

Gestational Diabetes Mellitus

Infections in Pregnancy

Intrahepatic Cholestasis of Pregnancy

Minor Disorders of Pregnancy

Pre-conceptual Health

Pre-eclampsia

Preparation for Parenthood

References

Part II: Labour and Birth

First Stage of Labour

Promoting Normality

Second Stage of Labour

Third Stage of Labour

Challenges

Cord Prolapse

Eclampsia

Primary Postpartum Haemorrhage

Shoulder Dystocia

References

Part III: Postnatal Care

Contraception and Sexual Health

Facilitating Breastfeeding

Postnatal Health Assessment

Mental Illness After Childbirth

References

Part IV: Hot Topics

Breech Birth

Domestic Abuse

Obesity

Recognising the Deteriorating Woman

Sepsis

References

Conclusion: Top Tips for Examination Success

Preparation - Revision

Trying a Different Strategy

Being in the Exam

Reference

Index

End User License Agreement

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Guide

Cover

Table of Contents

Preface

Begin Reading

List of Tables

Part III: Postnatal Care

Table 1 Example of student revision tool for postnatal health assessment

Rapid Midwifery

Sarah Snow

Principal Lecturer and Lead Midwife for Education Oxford Brookes University

Kate Taylor

Senior Lecturer University of Worcester

Jane Carpenter

Third year MSc pre-registration midwifery student Oxford Brookes University

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Library of Congress Cataloging-in-Publication Data

Names: Snow, Sarah, 1966- , author. | Taylor, Kate, 1951- , author. | Carpenter, Jane, 1971- , author.

Title: Rapid midwifery / Sarah Snow, Kate Taylor, Jane Carpenter.

Description: Chichester, West Sussex, UK ; Hoboken, NJ : John Wiley & Sons Inc., 2016. | Includes bibliographical references and index.

Identifiers: LCCN 2015047745| ISBN 9781119023364 (pbk.) | ISBN 9781119023371 (Adobe PDF) | ISBN 9781119023388 (epub)

Subjects: | MESH: Midwifery–methods | Handbooks

Classification: LCC RG950 | NLM WQ 165 | DDC 618.2–dc23 LC record available\break at http://lccn.loc.gov/2015047745

9781119023364 [paperback]

A catalogue record for this book is available from the British Library.

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.

Cover image: ©, Science Photo Library/Gettyimages

Preface

Rapid Midwiferyis part of a series of revision guides that has the fundamental aim of supporting student learning. This book is primarily aimed at pre-registration and post-experience midwifery students who are in the first or second year of their programme. Both years are challenging, especially when the realities of a midwifery course become apparent and students are adapting to the inherent professional, academic and social demands of their programme. During the first year, the relentless approach of the first assessment can instil great stress in students and may be a pivotal decision point in their continuing forwards on the programme. This book is aimed at alleviating some of that stress. By offering bite-sized information that is thoroughly supported by current best evidence, this book will be a helpful revision tool in preparing for looming OSCEs and written examinations.

Rapid Midwifery has two distinct features. First, it is written in sections that closely mimic assessment criteria used in midwifery examinations. Although each university sets its own criteria, examinations are set to test broadly a student's knowledge of key physiology; principles of safe and effective midwifery care; relevant underpinning evidence and professional accountability. Second, each topic has been mapped against the 6Cs, using care as the base point. Although each aspect of midwifery that is addressed within this book can be mapped against a number of the 6Cs, we have decided to identify what we consider to be the most predominant and therefore most relevant ‘C’. We hope that this map will stimulate the reader to consider further their practice within the framework of compassionate midwifery care.

Rapid Midwifery is not a textbook, nor is it a complete and definitive guide to midwifery. It should be used wisely and strategically, alongside a wide range of other sources that explore the topics in greater breadth and depth. Rapid Midwifery is not designed to do anything more than support new midwifery students' revision and serve as an appetiser for the main course that is lifelong learning.

Sarah SnowAugust 2015

Acknowledgement

We would like to extend our grateful thanks to Dr Martin Spurin, Programme Manager for the Youth, Community and Families degree programmes at University College Birmingham, who contributed the Conclusion to this book.

Rapid midwifery compassionate care map – linked throughout the book with green highlighted text and adapted from the 6Cs: DH (2012) Compassion in Practice, Department of Health, London.

Part I

Antenatal Care

Antenatal Health Assessment

The main objective of antenatal care is to support the woman through pregnancy and to monitor the health and well-being of the woman and fetus. Although pre-conceptual care is advised (see Section 1.10), antenatal care generally commences at booking. The National Institute for Health and Care Excellence (NICE) provides a framework and recommended schedules for routine antenatal care (NICE 2014c); however, timely referral is required if the woman or fetus is at increased risk. All care should be evidence based and woman centred, enabling her to make informed choices about her care.

Key Points

The first antenatal contact with the woman requires comprehensive history taking, including relevant obstetric, medical and personal details. Determining risk, offering an early ultrasound scan for gestational age, together with health screening checks and tests should be discussed (NICE 2014b).

Blood pressure monitoring, urinalysis and abdominal examination are all essential components of antenatal care; however, other physical and emotional issues need to be considered.

Breast examination:

This is not routinely recommended (NICE 2014b); however, the woman may find information about breast changes to be reassuring. Breast tenderness and tingling often occur early in pregnancy and an early increase in size often occurs. Colostrum leakage is common.

Blood pressure:

A number of factors can influence blood pressure measurements, including time of day, size of cuff, maternal position and variations in technique. Midwives must fully understand the principal mechanisms that control blood pressure and other factors that can influence systolic and diastolic pressures, blood pressure phases and Korotkoff sounds.

Urinalysis:

Observation of the volume, colour, smell, deposits and specific gravity of urine offers a unique insight into the physiological workings of many body systems (Blows 2012).

Colour:

This is dependent on concentration and varies from pale straw (normal) to amber. Diet, drugs, bilirubinuria and haematuria affect the colour of urine. Haematuria is not normal and may be indicative of infection or trauma.

Clarity:

Urine should be clear. Cloudy or foamy urine can be caused by protein; cloudy and thick urine may be indicative of the presence of bacteria (Blows 2012). Routine midstream urine (MSU) screening for asymptomatic bacteriuria early in pregnancy to exclude asymptomatic pyelonephritis is currently recommended by NICE (2014b).

Odour:

The odour of urine can be influenced by food. However, a smell of pear-drops or nail-polish remover indicates the presence of ketones which may be due to fasting, vomiting or uncontrolled diabetes mellitus. Infection may cause the urine to smell offensive and, when accompanied by the presence of nitrates and/or leucocytes on test strips, further laboratory culture is required.

Specific gravity

is affected by both the water concentration and solute concentration in a urine sample and reflects the kidney's ability to concentrate or dilute urine.

pH

reflects the acidity or alkalinity of urine and a low pH may predispose to the formation of calculi (stones) in the kidneys or bladder (Waugh and Grant 2014).

Altered renal tubular function can increase renal excretion of glucose and protein. This needs to be considered when analysing urine.

Abdominal examination

is carried out from 24 weeks and is achieved by inspection, palpation and auscultation.

Inspection:

The uterus should be ovoid in shape, being longer than it is broad. The size and shape of the abdomen can give clues to the size and position of the fetus as pregnancy progresses. However, a full bladder, distended colon and obesity can make the assessment of fetal size difficult. Skin changes, such as linea nigra and striae gravidarum and scars from previous surgery, self-harm or domestic violence may be evident on abdominal inspection. Fetal movements may be reported from around 20 weeks (Bharj and Henshaw 2011).

Fundal palpation

determines the presence of a head or breech in the fundus. The head is hard and round and much more distinctive in outline than the breech.

Symphysis–fundal height (SFH) should be measured (in centimetres) and recorded at each antenatal appointment from 24 weeks (NICE 2014b). Measurements should be plotted on a customised chart. Further investigation is required if a single measurement plots below the 10th centile or serial measurements show slow growth by crossing centiles (RCOG 2013).

Lateral palpation

determines the position of the fetal back. This feels like a smooth continuous line of resistance, while fetal limbs feel like small irregular shapes on the opposite side. The fetal back cannot be felt if the fetus is in the occipito-posterior position (see Section 2.1.2), although fetal limbs can be felt on both sides of the midline (Bharj and Henshaw 2011).

Pelvic palpation

determines the presentation of the fetus, the attitude and degree of engagement. This is best carried out using a two-hand approach. If the head is above the pelvic brim then the head is not engaged. Once engaged, if the fingers of one hand slide further into the pelvis than the other, then the head is flexed. NICE (2014b) recommends that presentation should not be assessed by abdominal palpation prior to 36 weeks.

Auscultation

of the fetal heart is best heard at a point over the fetal shoulder, hence lateral palpation to identify the fetal back is useful. When the fetus is in the occipito-posterior position, the fetal heart can be heard at the midline or lateral borders. NICE (2014b) does not recommend antenatal auscultation or electronic fetal heart rate monitoring in women with uncomplicated pregnancies.

Vaginal discharge

often increases in pregnancy. It is usually white, non-offensive and non-irritant. If the discharge is associated with pain on micturition, soreness, itching or an offensive smell, then further investigations are required (see Section 1.7).

Oedema

should not be present at the initial assessment. However, it may occur as pregnancy progresses due to physiological changes. Oedema that is visible in the woman's face and hands and becomes increasingly pitted in the lower limbs may be indicative of hypertension, especially if other markers are present.

Varicosities

are common in pregnancy owing to the effect of progesterone on the smooth muscles of blood vessel walls. Redness and tenderness/pain and areas that appear white may be indicative of deep vein thrombosis and require medical referral.

Maternal weight and height

should be measured at the first contact with the pregnant woman. Routine weighing during pregnancy is not recommended unless clinical management can be influenced or if nutrition is a concern (NICE 2014b). Women who have a body mass index (BMI) of <18 or ≥30 kg/m

2

need referral to a consultant and other health professionals working in nutrition and weight management (NICE 2010) (see Section 4.3).

Essentials of Midwifery Care

NICE (2014b) offers comprehensive guidance for the provision of antenatal care, a summary of which is provided below to aid revision.

Management of care will depend on the individual needs of the woman. A holistic woman-centred approach is paramount and observations of physical characteristics are important, as these may give clues to current problems or problems that may arise.

When women are assessed and remain low risk, a midwifery-led model of care should be offered.

If problems arise, a clear referral pathway should be established to ensure that the woman is managed and treated by appropriate specialist team members (NICE 2014c).

Urinalysis for protein should be carried out at each antenatal visit to screen for pre-eclampsia; however, routine urinalysis for glycosuria is not recommended as pregnancy affects glomerular filtration and exceeds the renal threshold for glucose (Blackburn 2013).

Urinalysis is an everyday task in midwifery practice; however, its relevance in identifying underlying disease processes and infection should not be undervalued.

Although formal fetal movement counting is not recommended, women should be encouraged to be aware of their baby's usual pattern of movements. The Royal College of Obstetricians and Gynaecologists (RCOG) gives guidance on the management of women with reduced fetal movements (RCOG 2011c).

Ultrasound estimation for suspected large for gestational age babies is not recommended for low-risk women. However, the RCOG (2013) recommends that women with a single SFH that plots below the 10th centile or serial measurements that demonstrate slow or static growth by crossing centiles should be referred for ultrasound measurement of fetal size.

Vaginal discharge should be differentiated from unexplained vaginal wetness to exclude amniotic fluid leak.

Professional Accountability

The midwife is required to facilitate and respect maternal choice. This can occur only if information is timely and appropriate.

Midwives should be aware of local protocols and national guidelines to ensure that referral to appropriate members of the multidisciplinary team is made when deviations from the norm are identified.

Accurate, contemporaneous documentation should reflect all care given and planned.

Further Resources

Geeky Medics.

How to Take an Accurate Blood Pressure

,

https://www.youtube.com/watch?v=f6HtqolhKqo

.

Anxiety and Depression

It is important to recognise that depression, anxiety and stress during pregnancy are at least as common as an altered emotional state during the puerperium. Glover (2014) identified that the emotional health of women during pregnancy remains a neglected aspect of maternity care. In addition, Brockington (1998) observed that the focus on the concept of ‘postnatal depression’ has detracted from the need to recognise and manage it like any other depressive illness that occurs during a woman's life span.

Key Points

Around 3–17% of women experience depressive illness during pregnancy (Leight

et al

. 2010).

Mindfulness-based cognitive therapy is associated with a significant reduction in both the incidence and reoccurrence of depression. It may also be an effective strategy for women who do not respond to other therapies such as cognitive behavioural therapy (CBT) (Segal

et al

. 2012).

Consideration and understanding of the context of a pregnant woman's anxiety or depression are crucial when determining care (Dunkel Schetter and Tanner 2012).

Anxiety and depressive symptoms in pregnancy are associated with preterm birth and low birth weight infants (Dunkel Schetter and Tanner 2012).

Evidence suggests that if a woman is stressed, anxious or depressed during pregnancy, her child is more likely to experience adverse outcomes, including emotional problems (O'Connor

et al

. 2002) and cognitive impairment (van den Bergh and Marcoen 2004).

The Family Nurse Partnership (2015) remains the only intervention that starts in pregnancy and is associated with improved outcomes for child behaviour (Glover 2014). It also has one of the most robust evidence bases for successful interventions with the care of vulnerable parents and babies.

The Mind ‘Building Resilience for Better Mental Health’ project reports that supporting pregnant women and new mothers to adopt strategies that manage altered mood helps them to stay well (Steen

et al

. 2015).

Essentials of Midwifery Care

NICE (2014a) offers a number of recommendations for the care and support of women, including:

Asking questions that are designed to identify depression as part of the general discussion about the woman's mental health at booking. This may then trigger referral to her GP or mental health professional. Examples of such questions include:

During the past month, have you often been bothered by feeling down, depressed or hopeless? During the past month, have you often been bothered by having little interest or pleasure in doing things?

Providing information to the woman and her partner about mental health during pregnancy, including treatment and prevention options, for example, psychological interventions and medication.

Monitoring symptoms regularly throughout pregnancy and referring women where appropriate for facilitated, self-help interventions. More severe symptoms may require high-intensity psychological interventions such as CBT.

Involving the woman (and her partner/family) in all aspects of her care and acknowledging the woman's central role in decision-making.

Recognising the impact of any mental health issue on the woman's relationship with her partner and family.

Developing an integrated care plan that clearly sets out the care and treatment of the mental health problem. This includes the involvement of other agencies, for example, mental health services.

Professional Accountability

Asking pregnant women sensitive questions about their mental health requires

courage

; however, a midwife's duty of care encompasses all aspects of a woman's mental and physical health.

Record keeping is an important aspect of caring for women with mental health needs and these records may not be conventional written ones. For example, women may value a record of their consultation in a variety of formats, e.g. audio, visual or verbal (NICE 2014a).

When working with girls and young women who disclose mental health issues, midwives must be clear about local and national guidelines regarding confidentiality and safeguarding.

Further Resources

Family Nurse Partnership,

http://fnp.nhs.uk

/.

Bio-physical Tests

Blood Tests

Blood tests in pregnancy fall into two main categories, diagnostic and screening. NICE (2014b) further categorises blood testing into screening for haematological conditions, screening for haemoglobinopathies, screening for Down syndrome (and other trisomies) and screening for infection. Some blood tests are routinely offered at the initial assessment. Others are offered at specific times during pregnancy or as indicated, in order to determine and manage the sequelae of specific complications. At the initial antenatal assessment, women are also routinely offered screening for certain infections (see Section 1.10).

Blood tests offered at the initial assessment include the following.

ABO Blood Group and Rhesus (Rh) Factor

Key Points

What determines a blood group is the presence or absence of a range of different proteins (antigens) on the red blood cell membrane.

Antigens on the red blood cell membrane can stimulate an immune response from antibodies in the plasma if transferred from one individual to another (Waugh and Grant 2014), in this instance between mother to baby.

Confirmation of a woman's blood group and Rh status is necessary to prevent a potentially fatal transfusion reaction (should a blood transfusion be required) and to prevent haemolytic disease of the newborn (HDN)

1

(Qureshi

et al

. 2014).

Determined by genetic control, the Rh grouping system involves many different antigens (which produce antibodies), with D being the most potent antigen and the one most commonly involved in incompatibility between mother and fetus causing HDN.

Essentials of Midwifery Care

Both the British Committee for Standards in Haematology (Qureshi et al. 2014) and the RCOG (2014) give guidance for the management of women with red cell antibodies during pregnancy. It is essential that midwives are aware of the following in order to provide effective care:

To reduce the incidence of HDN, women should be screened for atypical red cell alloantibodies early in pregnancy and again at 28 weeks, regardless of RhD status.

All RhD-negative women should be offered antenatal anti-D immunoglobulin (Ig) prophylaxis in accordance with local guidelines for dosage and timing of administration (NICE 2014b). If a sensitising episode should occur, for example, miscarriage, amniocentesis or external cephalic version, further administration of anti-D is required and within 72 hours of the event (Qureshi

et al

. 2014; RCOG 2014).

The amount of anti-D required is assessed by a Kleihauer blood test, which confirms the presence and estimates the number of fetal cells in the maternal circulation.

Consideration should be given to offering testing to the woman's partner in order to determine whether anti-D prophylaxis is necessary (NICE 2014b), although this can be a sensitive paternity issue.

Full Blood Count

Key Points

A full blood count is one of the most common blood tests taken in pregnancy as it can provide important ‘clues’ to a woman's general health.

There are three types of blood cells: erythrocytes (red cells and the most abundant), platelets (thrombocytes) and leucocytes (white cells).

Haemoglobin (Hb) is the most frequently referred to index (Blann 2006), with almost the entire weight of an erythrocyte (red blood cell) consisting of haemoglobin.

Each haemoglobin molecule consists of a pigmented iron-containing complex called haem and a polypeptide protein (globulin). The iron atoms play a key role in the oxygen-carrying capacity of erythrocytes (Waugh and Grant 2014).

Physiological anaemia describes a fall in Hb concentration due to the physiological changes that occur in normal pregnancy.

If the concentration of erythrocytes is low, as indicated by the red cell count (RCC), this may also be indicative of anaemia. If concentrations are high, then polycythaemia should be considered.

When the mean cell volume (MCV) is low, then serum ferritin levels should be investigated. Serum ferritin is a stable glycoprotein that accurately reflects iron stores.

Iron deficiency represents a spectrum of anaemias ranging from iron depletion to iron deficiency anaemia (Pavord

et al

. 2012).

Abnormal clinical findings may indicate a spectrum of anaemic disorders, polycythaemia or congenital haemoglobinopathies such as sickle cell disease and thalassaemia (Blann 2006).

Leucocytes are normally found in low concentrations; however, rising white cell numbers usually indicate infection or trauma. They therefore play an important role in the body's defence mechanism.

Other white blood cells include neutrophils, which protect the body from bacterial invasion; eosinophils, which have a specialist role in the elimination of parasites; basophils, which are associated with allergic reactions; and monocytes, which defend the body from bacterial, fungal and other pathogens by phagocytosis.

Lymphocytes make immunoglobulins (antibodies capable of recognising and attacking invading pathogens) and aid antibody production (Blann 2006).

Platelets (thrombocytes) play an important role in haemostasis. Platelets quickly adhere to each other when blood vessels are damaged, releasing substances that attract more platelets to the site to form a platelet plug (Waugh and Grant 2014).

Essentials of Midwifery Care

A full blood count is taken at the initial assessment and routinely during pregnancy, typically at 28 weeks (NICE 2014b).

NICE (2014b) recommends that when Hb levels fall outside the normal range for pregnancy (11 g/100 ml at first contact and 10.5 g/100 ml at 28 weeks), this should be investigated and iron supplementation considered.

Routine iron supplementation for all women is not recommended in the United Kingdom. However, all women should be given dietary information to maximise iron intake and absorption (Pavord

et al

. 2012).

In pregnancy, platelet levels may fall but usually remain within the normal range for non-pregnant women. A rise may be indicative of infection and an abnormal decrease should be viewed with suspicion and therefore investigated (Boyle 2011).

Haemoglobinopathies are a complex group of genetically acquired conditions. They occur in individuals who inherit two haemoglobin gene variants which lead to the synthesis of abnormal haemoglobin and increased red cell membrane fragility. The resulting reductions in the oxygen-carrying capacity and life span of the red cells are characteristics of sickle cell anaemia and thalassaemia (Blackburn 2013).

Sickle Cell Disease

Key Points

Sickle cell disease (SCD) exhibits geographical variations, with the highest prevalence amongst those of Black African and Black Caribbean family origin. Sickle cell disease affects 1 in every 2000 births in England (NHS 2011).

The pattern of inheritance is such that one gene from each parent (homozygous genotype for HbSS) results in a sickle cell-positive offspring.

Offspring who inherit one gene (heterozygote) have sickle cell trait (HbAS) and usually do not display the disease (Yerby 2010a).

In SCD, the characteristic sickle-shaped erythrocytes result when abnormal, deoxygenated haemoglobin molecules become misshaped.

Sickle cells do not move smoothly through the circulation and therefore cause an obstruction to blood flow, resulting in intravascular clotting, tissue ischaemia and infarction (Waugh and Grant 2014).

Normal haematological, cardiovascular, renal and respiratory changes during pregnancy place the woman and infant at greater risk of ‘sickle crises’ and complications such as an increased risk of thromboembolic events, antepartum haemorrhage and pre-eclampsia.

Fetal and neonatal complications such as prematurity and growth restriction may arise due to placental infarction and fetal hypoxia (RCOG 2011a; Blackburn 2013).

Thalassaemias

Key Points

Thalassaemias are a group of hereditary haemolytic anaemias, most prevalent in those of Mediterranean, African-Caribbean, Chinese and Asian origin.

They are characterised by an impaired and unbalanced synthesis of either the two α-globin or two β-globin chains (Waugh and Grant 2014).

The phenotype and severity of those with α-thalassaemia are dependent on the number of missing or altered genes involved in α-chain production.

Those with one or two affected genes have either a silent presentation or mild anaemia. If all four genes are missing, the fetus cannot synthesise either normal fetal haemoglobin or adult haemoglobin. These infants develop cardiac failure and hydrops fetalis and are often stillborn.

Until stem cell transplants are readily available, affected individuals require lifelong blood transfusions (Blackburn 2013).

β-Thalassaemia major results from the inheritance of a defective β-globin gene from each parent and therefore the fetus is homozygous.

This results in a severe transfusion-dependent anaemia. Many girls with thalassaemia major die in childhood or adolescence and those who survive are often amenorrheic and infertile.

The heterozygous state, β-thalassaemia trait (thalassaemia minor) causes mild to moderate microcytic anaemia. Those affected are generally asymptomatic, although haemoglobin levels are reduced.

Essentials of Midwifery Care

Both sickle cell and β-thalassaemia major can restrict a child's or adult's ability to conduct normal daily activities. The NHS sickle cell and thalassaemia screening programme (NHS 2011) sets out standards for antenatal and newborn screening and the RCOG (2011a) guideline makes recommendations for the management of sickle cell disease in pregnancy. These, together with the RCOG (2014) Management of Beta Thalassaemia in Pregnancy provide evidence-based guidance for care:

Information about screening for sickle cell diseases and thalassaemias, including the implications of carrier status, should be given to pregnant women at the first contact with the midwife, ideally before 10 weeks.

In low-prevalence trusts, a family origin questionnaire (FOQ) should be used to assess risk. In high-prevalence trusts, all pregnant women should also be offered screening.

When the woman is identified as being affected or a carrier, the father of the baby should also be offered screening.

Care for all women whose pregnancy is complicated by any form of haemoglobinopathy should be provided by a multidisciplinary team including an obstetrician, a midwife with experience of high-risk antenatal care and a haematologist with an interest in haemoglobinopathies (RCOG 2011a, 2014).

Screening tests for Down (T21), Edwards (T18) and Patau (T13) Syndromes

Key Points

Where a fault during meiosis occurs, three copies of a chromosome may result and give rise to a named trisomy (Waugh and Grant 2014), for example, Down syndrome. In the United Kingdom, all pregnant women are therefore offered antenatal screening.

The eligibility criterion for Down syndrome screening is all women with a singleton or twin pregnancy at ≤20+0 weeks. The eligibility criterion for Edwards and Patau syndromes is all women with singleton or twin pregnancy at <14+1 weeks. In each case, the gestational age in weeks must be confirmed by ultrasound scan (Public Health England 2015).

Women presenting in the first trimester between 10+0 and 14+1 weeks are offered the combined test to calculate the risk of the pregnancy being affected by Down, Edwards and Patau syndromes.

The combined test uses maternal age, the nuchal translucency (NT) measurement and two biochemical markers, together with gestational age, which is calculated from the fetal crown–rump length (CRL).

Women presenting between 14+2 and 20+0 weeks are offered the quadruple test for Down (T21) syndrome only. The optimal time for this test is 16 weeks.

The quadruple test uses maternal age and four biochemical markers, including AFP and hCG.

Essentials of Midwifery Care