Clinical Green Top Guidelines

Clinical Green Top Guidelines
The Management of Early Pregnancy Loss (25) - Oct 2000

1. Introduction

Miscarriage is known to occur in 10-20% of clinical pregnancies1 and accounts for 50,000 in-patient admissions to hospital in the United Kingdom (UK) annually.2 Apart from the widespread introduction of ultrasound, clinical management has changed little in the last 50 years and has commonly been based on tradition rather than a sound evidence-base.3An example of this was the use of bed-rest, which does not affect the outcome in threatened miscarriage. Until recently miscarriage has received less attention in the medical literature compared to other pregnancy-related problems. The majority of women with miscarriage are referred to hospital for assessment and up to 88% currently undergo surgical uterine evacuation.3 In this guideline, developments in the clinical management of miscarriage are reviewed, including the role of the early pregnancy assessment unit (EPAU) and non-surgical approaches to uterine evacuation. Miscarriage can be associated with significant psychological sequelae and recommendations will also be made in relation to medical terminology and the support and counselling offered to women after miscarriage. Ectopic pregnancy, recurrent miscarriage and gestational trophoblastic disease will not be dealt with specifically as they are discussed in separate RCOG guidelines. Although primarily aimed at the gynaecologist, it is hoped that all practitioners dealing with miscarriage, and their patients, will find this guideline useful.

2. Identification and assessment of evidence

A search of Medline Plus was carried out, as well as RCOG publications. The key-words used were miscarriage, spontaneous abortion, uterine evacuation, misoprostol and prostaglandin.

The definitions of the types of evidence used in this guideline originate from the US Agency for Health Care Policy and Research. Where possible, recommendations are based on, and explicitly linked to, the evidence that supports them. Areas lacking evidence are highlighted and annotated as 'Good Practice Points'.

3. Terminology

The medical term 'spontaneous abortion' should be replaced with the term 'miscarriage'. Appropriate terminology should also be used to describe the different types of miscarriage.
Many journals and textbooks continue to use the medical term 'spontaneous abortion' rather than 'miscarriage'.4 This and other inappropriate terminology (e.g. 'pregnancy failure', 'abnormal pregnancy', etc) may contribute to the development of negative self-perceptions in a group of women already feeling a sense of failure, and perhaps shame, guilt and insecurity.5 In 1997, a Study Group of the Royal College of Obstetricians and Gynaecologists recommended that traditional medical terminology should be changed (for example: 'miscarriage' replacing 'spontaneous abortion' and 'incomplete miscarriage' replacing 'incomplete abortion').6 Since the introduction of transvaginal ultrasound, 'missed abortion' (presence of a non-viable fetus) and 'anembryonic pregnancy' (absent fetal echo) are felt to reflect different aspects or stages of the same clinical process. Recommended alternatives which may be used for both include 'silent miscarriage', 'delayed miscarriage'4 or 'early fetal demise'.6 Evidence
Level IV

4. Service provision

All units should provide an early pregnancy assessment service with direct access for GPs and patients. Ideally, the service should be sited in a dedicated area with appropriate staffing. It should be available on a daily basis, at least during the normal working week.
Management of miscarriage based on in-patient emergency admission is frequently described by patients in negative terms.7,8 The benefits of an out-patient EPAU service were described by Bigrigg and Read in 1991.9 A dedicated clinic can streamline the management of women with early pregnancy bleeding or pain and thus improve the quality of care. Women are offered thorough assessment with a confirmed diagnosis (in most cases at first visit) in the presence of a supportive multidisciplinary team. The mean admission time for women requiring treatment was reduced from three (range 1.5-5.0) days to one day. Women are no longer separated from their families for long periods and there are potentially significant economic benefits for the NHS, with reduced use of in-patient beds.9

An effective EPAU requires an efficient appointments system, an appropriate setting (with an area for counselling), up to date ultrasound equipment (including transvaginal probes) and easy access to laboratory facilities (for rhesus antibody testing and selective serum hCG estimation).2,10,11 Direct access to the appointments system should be available to all practitioners in the primary care setting (including GPs, nurses, midwives and health visitors) as well as to other hospital departments (e.g. accident and emergency). Communication will be facilitated by use of standardised referral and discharge letters. Certain patients (e.g. with previous ectopic, recurrent miscarriage, etc) can be encouraged to access the service in future pregnancies by direct self-referral using the appointments system. Staffing is extremely important and requires appropriately trained personnel. The exact staffing of individual units should be agreed locally. The service should be available on a daily basis during the normal working week (an additional limited service at weekends would be ideal). Junior doctors at SHO level should attend the EPAU to gain experience in the management of women who miscarry. This should be in a supervised capacity.

 Evidence
Level IV

5. Diagnosis and investigation

EPAUs should use and develop diagnostic and therapeutic algorithms of care. In particular, these should include management of 'suspected ectopic pregnancy' (including serum hCG) and the 'indeterminate' ultrasound scan.
The majority of patients attending an EPAU can be managed using ultrasound scans and urine-based hCG tests. However, in view of the difficulty in diagnosing some cases of early ectopic pregnancy and its potentially serious implications, the RCOG Study Group felt that access to serum hCG estimation was essential (with results available within 24 hours).6 Patients with miscarriage or ectopic pregnancy who are managed expectantly, may require serial serum hCG monitoring in selected cases. The effective functioning of an EPAU requires close liaison with local laboratory services. Evidence
Level IV
EPAUs should have access to transvaginal ultrasound with staff appropriately trained in its use.
A transvaginal scan (TVS) will be required in approximately 40% of women referred to an EPAU.11 TVS is an acceptable intervention for early pregnancy dating in an antenatal clinic setting, with 88% of women accepting a TVS and 95% stating that they would have one again in the future.12 There are no publications describing its acceptability in an EPAU setting. Ultrasound assessment is particularly reliable in confirming the diagnosis of complete miscarriage.13 The sonographer should be formally trained in the use of both transabdominal and transvaginal ultrasound and ideally produce reports using standardised documentation as proposed by the Joint Working Party of the RCR/RCOG.14 Ultrasound practice must conform with the recommendations of the British Medical Ultrasound Society. Evidence
Level IV
Non-sensitised rhesus (Rh) negative women should receive anti-D immunoglobulin in the following situations: ectopic pregnancy, all miscarriages over 12 weeks (including threatened), all miscarriages where the uterus is evacuated, and for threatened miscarriages under 12 weeks when bleeding is heavy or associated with pain.
Routine antenatal blood tests can be checked in the EPAU, but it is vital that Rh antibody status is available promptly to allow appropriate administration of anti-D immunoglobulin. The following recommendations are based on the RCOG guideline for Rh prophylaxis.15
  • Confirmed miscarriage: anti-D should be given to all non-sensitised Rh negative women who miscarry after 12 weeks, whether complete or incomplete and to those who miscarry below 12 weeks when the uterus is evacuated (either surgically or medically).
  • Threatened miscarriage: anti-D should be given to all non-sensitised Rh negative women with threatened miscarriage after 12 weeks. Routine administration of anti-D is not required below 12 weeks when the fetus is viable, unless the bleeding is heavy or associated with abdominal pain. If there is clinical doubt then anti-D should be given.
Discharge documentation from the EPAU should clearly state whether or not anti-D was given.		 Evidence
Level II

6. Treatment

Surgical uterine evacuation for miscarriage should be performed using suction curettage.
Since the 1800s surgical uterine evacuation has been the standard treatment offered to women who miscarry. This is based on an assumption that retained tissue increases the risks of infection and haemorrhage. However, the introduction of surgical evacuation occurred at a time when illegal abortion was common and antibiotics were not available. It remains the treatment of choice if bleeding is excessive, if vital signs are unstable or when infected tissue is present in the uterine cavity. Studies suggest that <10% of women who miscarry fall into these categories.16

Sharp/blunt curettage is usually used in UK practice for cases of incomplete miscarriage and suction curettage for delayed miscarriage. A randomised trial comparing the two methods in the management of incomplete miscarriage concluded that suction curettage was safer and easier.17 Serious complications of surgery include perforation, cervical tears, intra-abdominal trauma, intrauterine adhesions and haemorrhage. The reported incidence of serious morbidity using a similar surgical technique for induced abortion is 2.1%18 with a mortality of 0.5 per 100,000.19

Curettage under local anaesthesia is rarely used in the UK but is well-described and commonly used in the United States20 as well as many European, Asian and African countries. The technique may be appropriate for selected women and its wider use needs further assessment.

In all cases where surgery is being considered the need for cervical priming should be assessed.

 Evidence
Level Ib
All at risk women undergoing surgical uterine evacuation for miscarriage should be screened for Chlamydia trachomatis.
The routine use of antibiotic prophylaxis in reducing the incidence of pelvic infection has been clearly demonstrated in induced abortion (see RCOG National Evidence-based Guideline No 7). A randomised trial of prophylactic doxycycline in curettage for incomplete miscarriage did not confer an obvious benefit, but the study was of insufficient power to detect a clinically meaningful change in infectious morbidity.21 Until further research is published, it is recommended that all at risk women undergoing surgical evacuation continue to be screened for Chlamydia trachomatis. This particularly applies to women under the age of 25. Evidence
Level IV
Medical and expectant methods are also effective in the management of confirmed miscarriage.
'Medical evacuation' and 'expectant management' are accepted alternative techniques, although they have not replaced surgical evacuation. In a partially randomised study comparing surgical and medical evacuation, 20% of women expressed a strong preference for medical management.22 The main reasons given for their choice were 'avoidance of general anaesthesia' and the feeling of being 'more in control'.

Various medical methods have been described using prostaglandin (PG) analogues (gemeprost or misoprostol) with or without antiprogesterone priming (mifepristone).22-31 Efficacy rates vary widely from 13% to 96% and factors that seem to influence the outcome include the type of miscarriage and the use and timing of ultrasound for follow-up. Total dose of PG, duration of use and route of administration are also important. Higher success rates (70-96%) were associated with an initial diagnosis of incomplete miscarriage,22,24 higher dose misoprostol,22,30 vaginal administration of PG28,31 and clinical follow-up without routine ultrasound.22-24

Incomplete miscarriage may be managed with PG alone. Misoprostol is a cheap, effective PG-analogue which is active orally and vaginally. Evidence suggests the latter route may be more effective.28 In the presence of a closed cervix and intact sac ('early fetal demise' or 'delayed miscarriage'), effective regimens involved higher dose PG with longer duration of use30 or alternatively, priming with antiprogesterone.22,23 One randomised trial showed no statistical difference in efficacy between surgical and medical evacuation for incomplete miscarriage and for early fetal demise at gestations <71 days or sac diameter <24mm.22 Patient acceptability for both methods was equal. There was a reduction in clinical pelvic infection after medical evacuation (7.1 vs 13.2% p<0.001). With increasing gestation and sac size, the acceptability of medical methods fell to 85%. Johnson et al showed an increase in pain and bleeding with medical methods which may be a factor influencing acceptability.32

Medical evacuation has potential economic benefits for the NHS with an average cost-saving of £50 per case.33 However, a recent study does indicate that expectant management could be as effective as medical treatment.34

Observational and controlled trials of expectant versus surgical management again show wide variations in reported efficacy (25-100%).35-38 Similar factors affect the success rate and include type of miscarriage, duration of follow-up and whether ultrasound or clinical assessment was used for review. Various ultrasound criteria were used to define 'retained products' at study entry. Nielsen et al included patients with an 'AP tissue diameter of 15-50mm' with ultrasound review at three days (efficacy 71%).35 Chipchase and James included all those with an 'AP tissue diameter <50mm' and reviewed patients clinically on three occasions up to six months (efficacy 100%).36 However, the mean AP diameter of tissue in those managed expectantly was only 11mm. These would have been defined as 'complete miscarriage' by Nielsen and excluded from his study. When ultrasound assessment of the uterine cavity shows heterogenous shadows with a maximum AP diameter of 15mm or less, genuine retained products are much less likely to be confirmed histologically.13 These cases of 'complete miscarriage' are best managed conservatively as there is a trend towards a lower complication rate compared to surgical management (3.0 vs 5.8% p=0.06).39

Lowest efficacy rates (25-43%)37,38 were related to cases with an intact sac and closed cervix (i.e. 'delayed miscarriage' or 'early fetal demise'). When managed expectantly, resolution may take several weeks and patients must be counselled appropriately or 20% will request surgical evacuation during the observation period.38 Objective assessment of women in a controlled trial of expectant versus surgical management revealed no difference in psychological morbidity related to the procedure.40

 EvidenceLevel Ib
Medical and expectant management should be offered only in units where patients have access to 24-hour telephone advice and immediate admission can be arranged.
Expectant management often results in resorption of retained tissue with little associated bleeding. However, further bleeding may occur if tissue is passed. With medical evacuation, one third of women will bleed or miscarry in the priming phase after antiprogesterone. It is important that women have direct telephone access to ward staff for advice and support. Emergency facilities must be available in the event of emergency admission. Evidence
Level IV
Concerns have been raised about the infective risks of non-surgical management,41 but published data suggest a reduction in clinical pelvic infection and no adverse affects on future fertility.22,36,42 Further research should aim to improve present regimens and clarify which of the three treatment options is best for individual women. Evidence
Level IV
Tissue obtained at the time of miscarriage should be examined histologically to confirm pregnancy and to exclude ectopic pregnancy or gestational trophoblastic disease.
Heath et al have suggested that there is no obvious benefit in routine histological investigation of tissue obtained from cases of pregnancy termination and miscarriage.43 However, within their sub-group of 468 undergoing surgical evacuation for miscarriage, there were two cases of ectopic pregnancy diagnosed 25 and 28 days post-evacuation (an incidence of 0.4%). Neither was suspected on scan but histology had reported 'decidua only'. In view of the maternal risks associated with ectopic pregnancy, the RCOG Study Group recommended that tissue obtained at the time of uterine evacuation (medical or surgical) should be sent for histological examination. This may confirm the diagnosis of miscarriage and will help to exclude ectopic pregnancy or gestational trophoblastic disease.6 Evidence
Level IV

7. Psychological aspects of early pregnancy loss

All professionals should be aware of the psychological sequelae associated with miscarriage and should provide support and follow-up, as well as access to formal counselling when necessary.
Many publications confirm the negative psychological impact of early pregnancy loss on a significant proportion of women, their partners and families.44-47 For some, the distress is both severe and protracted even with miscarriage early in the first trimester.45 This may not be appreciated by all professionals involved in miscarriage care. Many of the specific issues which women feel are important are discussed by Moulder.47 Women who miscarry should be offered the opportunity to attend for follow-up. This may involve EPAU staff or carers in the community (GP, nurse, midwife or health visitor). Plans for follow-up should be clearly recorded in the discharge letter from the EPAU. Continuing awareness of the potential effects of miscarriage is required, with a willingness to involve appropriate support and counselling services when needed. Evidence
Level III

SUPPORT GROUP

The Miscarriage Association (Registered Charity No 1076829). c/o Clayton Hospital, Northgate, Wakefield, West Yorkshire, WF1 3JS. Telephone 01924 200799.

References

 
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APPENDIX

Clinical guidelines are: 'systematically developed statements which assist clinicians and patients in making decisions about appropriate treatment for specific conditions'. Each guideline is systematically developed using a standardised methodology. Exact details of this process can be found in 'Clinical Governance Advice No 1: Guidance for the development of RCOG green-top guidelines' (available on the RCOG websitehttp://www.rcog.org.uk/mainpages.asp?PageID=189). These recommendations are not intended to dictate an exclusive course of management or treatment. They must be evaluated with reference to individual patient needs, resources and limitations unique to the institution and variations in local populations. It is hoped that this process of local ownership will help to incorporate these guidelines into routine practice. Attention is drawn to areas of clinical uncertainty where further research may be indicated.

The evidence used in this guideline was graded using the scheme below and the recommendations formulated in a similar fashion with a standardised grading scheme.

Classification of evidence levels

Ia Evidence obtained from meta-analysis of randomised controlled trials.
Ib Evidence obtained from at least one randomised controlled trial.
IIa Evidence obtained from at least one well-designed controlled study without randomisation.
IIb Evidence obtained from at least one other type of well-designed quasi-experimental study.
III Evidence obtained from well-designed non-experimental descriptive studies, such as comparative studies, correlation studies and case studies.
IV Evidence obtained from expert committee reports or opinions and/or clinical experience of respected authorities.

Grades of recommendations

Requires at least one randomised controlled trial as part of a body of literature of overall good quality and consistency addressing the specific recommendation. (Evidence levels Ia, Ib)
Requires the availability of well controlled clinical studies but no randomised clinical trials on the topic of recommendations. (Evidence levels IIa, IIb, III)
Requires evidence obtained from expert committee reports or opinions and/or clinical experiences of respected authorities. Indicates an absence of directly applicable clinical studies of good quality. (Evidence level IV)

Good Practice Point

Recommended best practice based on the clinical experience of the guideline development group.
This Guideline was produced on behalf of the Guidelines and Audit Committee of the Royal College of Obstetricians and Gynaecologists by:

Mr K Hinshaw MRCOG, Sunderland and Dr A Fayyad, Sunderland.

Peer reviewed by:
Ms R Bender-Atik, National Director of the Miscarriage Association; Miss M A Bigrigg MRCOG, Glasgow; 
Dr C B Everett DRCOG, Alton (GP); Dr E R M Jauniaux, London; Dr G S McCune FRCOG, Milton Keynes; 
Dr K J Thong MRCOG, Edinburgh; Mr S K Vyas MRCOG, Bristol; Ms J Wray, Manchester (midwife).

Valid until October 2003
unless otherwise indicated