Recommendations from NICE will ensure that antenatal care is no longer rooted in the past but based on the best available evidence, says Dr Anne White
Antenatal care has remained largely unchanged since the 1920s. The pattern of visits recommended at that time (monthly until 30 weeks, fortnightly to 36 weeks and weekly until delivery) is still recognisable. It has been said that antenatal care has escaped critical assessment.1
Patients find that procedures vary in different areas of the country. The recently published NICE guideline Antenatal care: Routine care for the healthy pregnant woman considers the care women should receive rather than how antenatal services should be provided.
The aims of the guideline
The guiding principle of the guideline is that pregnancy is a normal physiological process, and any intervention offered should have known benefits and be acceptable to the pregnant woman. The guideline’s aims are:
- To offer information on best practice for baseline clinical care of all pregnancies, and comprehensive information on the antenatal care of the healthy woman with an uncomplicated singleton pregnancy.
- To provide evidence-based information for clinicians and pregnant women to make decisions about appropriate treatment in specific circumstances.
- To ensure that the schedule of antenatal appointments is determined by the function of the appointments.
The development process
The guideline was developed by a multidisciplinary and lay working group. Members included representatives of patient groups, GPs, midwives, obstetricians, a radiographer, a neonatologist and the director of the United Kingdom Confidential Enquiries into Maternal Deaths. Staff from the National Collaborating Centre for Women’s and Children’s Health undertook the systematic searches, retrieval and appraisal of evidence.
Recommendations were graded in accordance with the level of evidence upon which they were based Figure 1, (below).
|Figure 1: Key to grades of recommendations and levels of evidence|
|NICE Clinical Guideline 6. Antenatal Care: Routine care for the healthy pregnant woman. NICE, 2003. Reproduced with kind permission from the National Institute for Clinical Excellence.|
The guideline’s key recommendations are given in Figure 2 (below).
|Figure 2: Key recommendations|
|NICE Clinical Guideline 6. Antenatal Care: Routine care for the healthy pregnant woman. NICE, 2003. Reproduced with kind permission from the National Institute for Clinical Excellence. Available from www.nice.org.uk|
Overview of antenatal care
It is estimated that a woman with an uncomplicated first pregnancy will need 10 antenatal appointments and a parous woman with an uncomplicated pregnancy will require seven visits. At the first visit it is important to identify whether the woman may need additional care, for example if she is aged more than 40 years or less than 19 years, or if she has had three or more miscarriages.
The first appointment should take place before 12 weeks, and because women have considerable information needs, a second appointment may be necessary at around this time. Areas to be covered at these visits include:
- Giving information on diet and lifestyle, pregnancy care services and maternity benefits
- Offering screening tests, the purpose of which should be clearly explained before they are undertaken
- Measuring body mass index 2 and blood pressure, and testing urine for proteinuria.
Before 16 weeks the following tests should be arranged:
- Blood tests for blood group, rhesus status, red cell alloantibodies, haemoglobin, hepatitis B, HIV, rubella susceptibility and syphilis
- Urine test to screen for asymptomatic bacteriuria
- Ultrasound scan to determine gestational age
- Screening for Down’s syndrome should be offered.
- Antenatal care should be provided by a small group of carers with whom the woman feels comfortable. There should be continuity of care throughout the antenatal period (Grade A).
- The needs of each pregnant woman should be assessed at the first appointment and reassessed at each appointment throughout pregnancy because new problems can arise at any time.
Assessing gestational age
The guideline recommends that all pregnant women should be offered an early ultrasound scan to determine gestational age accurately, (rather than recording last menstrual period) and to detect multiple pregnancies.
The symphysis-fundal height should be measured and plotted at each antenatal appointment. This is included as a good practice point.
Screening for pre-eclampsia is a key role in antenatal care. Pre-eclampsia is a multisystem disorder associated with increased maternal and neonatal morbidity and mortality.
The incidence of pre-eclampsia ranges from 2% to 10%, depending on the population studied and the criteria used for diagnosis.3
Women with the following risk factors should be considered for more frequent blood pressure screening:4
- Age 40 years and above
- Family history of pre-eclampsia
- History of pre-eclampsia
- BMI at or above 35 at first contact
- Multiple pregnancy
Pre-existing vascular disease, e.g. hypertension or diabetes. At each appointment, the minimum requirement would be to give information concerning screening tests and symptoms of advanced pre-eclampsia. The woman’s blood pressure should be checked and urine tested for proteinuria.
The schedule of minimum appointments is given in Box 1 (below).
|Box 1: Schedule of minimum antenatal appointments|
|Nulliparous women||Parous women|
|Before 12 weeks*||Before 12 weeks*|
|16 weeks||16 weeks|
|28 weeks||28 weeks|
|34 weeks||34 weeks|
|36 weeks||36 weeks|
|38 weeks||38 weeks|
|41 weeks||41 weeks|
|*1 or 2 appointments|
- At first contact, a woman’s level of risk for pre-eclampsia should be evaluated so that a plan for her subsequent schedule of antenatal appointments can be formulated (Grade C).
- Whenever blood pressure is measured, a urine sample should be tested at the same time for proteinuria (Grade C).
Screening for fetal abnormalities
Screening should take place only when the woman has given her informed consent. She should be given written information about the procedure, including its nature, and purpose, and the meaning of detection rates, positive and negative screening results, and the consequences of abnormal and normal results also need to be explained.
The pregnant woman must have a full appreciation of the risks versus the benefits, and her right to accept or decline any test should be made clear.
The success of screening for anomalies is dependent upon the following factors: the type of anomaly, gestational age at the time of the scan, skill of the operator, the quality of equipment, and the time allowed for the scan. There is a wide variation in the provision of Down’s syndrome screening across the country. The guideline recommends that all pregnant women should be offered screening for Down’s syndrome and sets out the tests recommended, according to gestational age (see Figure 2, above).
- Pregnant women should be offered screening for Down’s syndrome with a test that provides the current standard of detection rate above 60% and a false positive rate of less than 5% (Grade B).5
- Pregnant women should be given information about the detection rates and false positive rates of any Down’s syndrome screening test being offered. A woman’s right to accept or decline the test should be made clear (Grade D).
Screening for infections
Screening for the following infections should be offered:
- Hepatitis B: effective postnatal intervention can be offered to the mother to reduce the risk of mother to child transmission6
- HIV: appropriate antenatal interventions can reduce mother to child transmission of HIV infection7
- Rubella: vaccination in the postnatal period can protect future pregnancies8
- Asymptomatic bacteriuria in early pregnancy by MSSU: the aim is to decrease the risk of pyelonephritis and preterm birth and its consequences.9
There is insufficient evidence to support screening for chlamydia (although this may change with the implementation of a national screening programme), cytomegalovirus, hepatitis C, toxoplasmosis, asymptomatic bacterial vaginosis, and group B streptococcus.
- Up-to-date randomised controlled trials are needed to confirm the benefits of screening for asymptomatic bacteriuria.
- Further research into the clinical effectiveness and cost-effectiveness of antenatal screening for group B streptococcus are needed.
At present, screening for gestational diabetes appears to be hampered by the lack of a clear definition, agreed diagnostic criteria and the evidence to show that intervention and treatment for this condition leads to improved outcome for mother or fetus.
The results of two ongoing studies, expected in 2004, are expected to resolve some of the issues surrounding the question of whether women should be routinely screened for diabetes.
- The evidence does not yet support routine screening for gestational diabetes mellitus and therefore it should not be offered (Grade B).10
Pregnancy increases the risk of domestic violence starting or escalating. The prevalence of domestic violence in pregnancy has been shown to be as high as 17% in England and Wales.11
- Health professionals need to be alert to the symptoms and signs of domestic violence and women should be given the opportunity to disclose domestic violence in an environment in which they feel secure (Grade D).
Implications for general practice
For GPs, implementing the new guideline will mean practical and organisational differences to the way they approach antenatal care.
A first appointment before 12 weeks would give women more time to make decisions about screening and to plan what care they wanted in pregnancy.
The guideline recommends that the frequency of appointments is reduced but that each appointment has a recognised purpose and should therefore take longer.
Box 2 (below) lists key points for GPs.
- At each antenatal appointment, midwives and doctors should offer consistent information and clear explanations, and should provide pregnant women with an opportunity to discuss issues and ask questions (Grade D).
- Midwife and GP-led models of care should be offered for women with an uncomplicated pregnancy. Routine involvement of obstetricians in the care of women with an uncomplicated pregnancy at scheduled times does not appear to improve perinatal outcomes compared with involving obstetricians when complications arise (Grade A).
Information and support
To help pregnant women to make informed decisions about their care, they must be given support and information, including who will undertake their care and where they will be seen. Taking women’s choices into account is vital to the decision-making process.
At the first appointment, women should be informed about pregnancy care services and options available and advised about lifestyle measures and screening tests. At each subsequent visit, in addition to offering clear and consistent information, midwives and doctors should give pregnant women the opportunity to ask questions and discuss issues.
This guideline will help to standardise antenatal care offered by PCOs and hospitals across the country. It will also act as a checklist for clinicians and women as well as informing women of what to expect at appointments.
National Institute for Clinical Excellence. Antenatal care: Routine care for the healthy pregnant woman NICE Clinical Guideline No. 6. London: NICE, 2003. Available from: www.nice.org.uk
- Cochrane AL. Effectiveness and efficiency: Random reflections on health services. London: Nuffield Provincial Hospitals Trust, 1972.
- Dawes MG, Grudzinskas JG. Repeated measurement of maternal weight during pregnancy. Is this a useful practice? Br J Obstet Gynaecol 1991; 98: 189-94.
- Walker JJ.Pre-eclampsia. Lancet 2000;356:1260-5.
- Duckitt K. Risk factors for pre-eclampsia that can be assessed at the antenatal booking visit: a systematic review. Presented at the International Society for the Study of Hypertension in Pregnancy Conference, 24-25 July 2003, Glasgow, 2003.
- Deeks JJ. Systematic reviews in health care: Systematic reviews of evaluation of diagnostic and screening tests. Br Med J 2001; 323: 157-62.
- Brook MG, Lever AM, Kelly D et al. Antenatal screening for hepatitis B is medically and economically effective in the prevention of vertical transmission: three years experience in a London Hospital. Q J Med 1989; 71: 313-7.
- Brocklehurst P, Volmink J. Antiretrovirals for reducing the risk of mother-to-child transmission of HIV infection. Cochrane Database of Systematic Reviews 2002; (3).
- Control and prevention of rubella: evaluation and management of suspected outbreaks, rubella in pregnant women, and surveillance for congenital rubella syndrome. MMWR Recomm Rep 2001; 50: 1-23.
- Smaill F. Antibiotic treatment for asymptomatic bacteriuria: antibiotic vs. no treatment for asymptomatic bacteriuria in pregnancy. Cochrane Database of Systematic Reviews 2002: (3).
- Scott DA, Loveman E, McIntyre L, Waugh N. Screening for gestational diabetes: a systematic review and economic evaluation. Health Technology Assessment 2002; 6: 1-172.
- Johnson JK, Haider F, Ellis K,Hay DM, Lindow SW. The prevalence of domestic violence in pregnant women. Br J Obstet Gynaecol 2003; 110: 272-5.
I would like to thank Dr Peter Brocklehurst, Ms Sue Lee, Mr Tim Overton, Professor Stephen Robson, Ms Julia Sanders, Dr Lindsay Smith and Ms Jane Thomas whose presentations at the guideline launch were of help in writing this article.