In addition to these evidence-based recommendations, the guideline development group also identifies points of best clinical practice in the original guideline document.
Levels of evidence (Ia-IV) and grading of recommendations (A-C) are defined at the end of the "Major Recommendations" field.
Effectiveness of Antenatal Corticosteroid Therapy
A - Clinicians should offer antenatal corticosteroid treatment to women at risk of preterm delivery because antenatal corticosteroids are associated with a significant reduction in rates of respiratory distress syndrome (RDS), neonatal death, and intraventricular haemorrhage.
B - Healthcare organisations and services should have policies and protocols in place for antenatal steroid treatment because the cost and duration of neonatal intensive care is reduced following corticosteroid therapy.
A - The optimal treatment-delivery interval for administration of antenatal corticosteroids is more than 24 hours but fewer than seven days after the start of treatment.
A - In preterm labour it is reasonable not to use tocolytic drugs, as there is no clear evidence that they improve outcome. However, clinicians should consider the use of short-term tocolysis if the few days gained can be put to good use, such as completing a course of corticosteroids, or in utero transfer.
A - If a tocolytic drug is used, ritodrine no longer seems to be the best choice. Atosiban or nifedipine appear to be preferable, as they have fewer adverse effects and seem to have comparable effectiveness. Atosiban is licensed for this usage in the United Kingdom (UK) but nifedipine is not.
Safety
A - Women may be advised that the use of a single course of antenatal corticosteroids does not appear to be associated with any significant maternal or fetal adverse effects.
Indications for Antenatal Corticosteroid Therapy
A - Every effort should be made to initiate antenatal corticosteroid therapy in women between 24 and 34 weeks of gestation with any of the following:
- Threatened preterm labour
- Antepartum haemorrhage
- Preterm rupture of membranes
- Any condition requiring elective preterm delivery
Between 35 to 36 weeks obstetricians might want to consider antenatal steroid use in any of the above conditions although the numbers needed to treat will increase significantly. [Evidence level Ia]
Antenatal education programmes or patient information leaflets should be considered to encourage early recognition of these conditions, in an effort to ensure early presentation and commencement of treatment. Maternity services should consider multidisciplinary staff training in providing information, including risk ratios, to women.
Dose and Route of Administration
B - Betamethasone is the steroid of choice to enhance lung maturation. Recommended therapy involves two doses of betamethasone 12 mg, given intramuscularly 24 hours apart.
Repeated Doses
A - If repeat courses of antenatal corticosteroids are contemplated then senior opinion should be sought as, at present, there is a lack of evidence to show significant benefit.
A - Obstetricians should consider enrolling their patients in randomised controlled trials if repeat corticosteroid therapy is contemplated.
Effectiveness of Thyrotrophin-Releasing Hormone
A - The use of thyrotrophin-releasing hormone is not recommended in combination with antenatal corticosteroids.
Definitions:
Grading of Recommendations:
Grade A - 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)
Grade B - Requires the availability of well-conducted clinical studies but no randomised clinical trials on the topic of recommendations (evidence levels IIa, IIb, III)
Grade C - Requires evidence obtained from expert committee reports or opinions and/or clinical experience of respected authorities. Indicates an absence of directly applicable clinical studies of good quality (evidence level IV)
Levels of Evidence:
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
