WHO recommendation on the diagnosis of gestational diabetes in pregnancy

WHO recommendation on the diagnosis of gestational diabetes in pregnancy

 

Recommendation

Hyperglycaemia first detected at any time during pregnancy should be classified as either gestational diabetes mellitus (GDM) or diabetes mellitus in pregnancy, according to WHO criteria.

(Recommended)

 

Publication history

First published: December 2016

Updated: No update planned

Assessed as up-to-date: December 2016

 

Remarks

This recommendation has been integrated from the 2013 WHO publication Diagnostic criteria and classification of hyperglycaemia first detected in pregnancy (the strength of the recommendation and the quality of the evidence were not stated) (1), which states that GDM should be diagnosed at any time in pregnancy if one or more of the following criteria are met:

  • fasting plasma glucose 5.1–6.9 mmol/L (92–125 mg/dL)
  • 1-hour plasma glucose 10.0 mmol/L (180 mg/dL) following a 75 g oral glucose load 2-hour plasma glucose 8.5–11.0 mmol/L (153–199 mg/dL) following a 75 g oral glucose load

Diabetes mellitus in pregnancy should be diagnosed if one or more of the following criteria are met:

  • fasting plasma glucose 7.0 mmol/L (126 mg/dL)
  • 2-hour plasma glucose 11.1 mmol/L (200 mg/dL) following a 75 g oral glucose load
  • random plasma glucose 11.1 mmol/L (200 mg/dL) in the presence of diabetes symptoms.

• WHO currently does not have a recommendation on whether or how to screen for GDM, and screening strategies for GDM are considered a priority area for research, particularly in LMICs.

• Diabetes mellitus in pregnancy differs from GDM in that the hyperglycaemia is more severe and does not resolve after pregnancy as it does with GDM.

• A systematic review of cohort studies shows that women with hyperglycaemia (diabetes mellitus and GDM) detected during pregnancy are at greater risk of adverse pregnancy outcomes, including macrosomia, pre-eclampsia/hypertensive disorders in pregnancy, and shoulder dystocia. Treatment of GDM, which usually involves a stepped approach of lifestyle changes (nutritional counselling and exercise) followed by oral blood-glucose-lowering agents or insulin if necessary, is effective in reducing these poor outcomes.

• There are many uncertainties about the cost–effectiveness of different screening strategies, the prevalence of GDM and diabetes mellitus according to the 2013 criteria in diverse populations, and the impact of earlier diagnosis on pregnancy outcomes.

• The usual window for diagnosing GDM is between 24 and 28 weeks of gestation. Risk factor screeningis used in some settings as a strategy to determine the need for a 2-hour 75 g oral glucose tolerance test (OGTT). These include a BMI of greater than 30 kg/m2, previous GDM, previous macrosomia, family history of diabetes mellitus, and ethnicity with a high prevalence of diabetes mellitus. In addition, glycosuria on dipstick testing (2+ or above on one occasion, or 1+ on two or more occasions) may indicate undiagnosed GDM and, if this is observed, performing an OGTT could be considered. (2)

• The management approach for women classified with diabetes mellitus in pregnancy (i.e. severe hyperglycaemia first detected in pregnancy) usually differs from the approach for women with GDM, particularly when diagnosed early in pregnancy; however, the principles of management are similar and both require referral and increased monitoring.

• Further information and considerations related to this recommendation can be found in the 2013 WHO guideline, available at: http://www.who.int/diabetes/publications/Hyperglycaemia_In_Pregnancy/en/

 

Background

Diabetes complicating pregnancy is associated with adverse maternal and perinatal outcomes (3). Lesser degrees of glucose intolerance have also been shown to be harmful (4). However, how one defines what constitutes glucose intolerance in pregnancy has been an issue of considerable controversy, complicating clinical practice and research over the last three decades. The main reason for this diagnostic dilemma is the large number of procedures and glucose cut-offs proposed for the diagnosis of glucose intolerance in pregnancy.

 

Methods

The ANC recommendations are intended to inform the development of relevant health-care policies and clinical protocols. These recommendations were developed in accordance with the methods described in the WHO handbook for guideline development (5). In summary, the process included: identification of priority questions and outcomes, retrieval of evidence, assessment and synthesis of the evidence, formulation of recommendations, and planning for the implementation, dissemination, impact evaluation and updating of the guideline.

The quality of the scientific evidence underpinning the recommendations was graded using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) (6) and Confidence in the Evidence from Reviews of Qualitative research (GRADE-CERQual)  (7) approaches, for quantitative and qualitative evidence, respectively. Up-to-date systematic reviews were used to prepare evidence profiles for priority questions. The DECIDE (Developing and Evaluating Communication Strategies to support Informed Decisions and Practice based on Evidence) (8) framework, an evidence-to-decision tool that includes intervention effects, values, resources, equity, acceptability and feasibility criteria, was used to guide the formulation and approval of recommendations by the Guideline Development Group (GDG) – an international group of experts assembled for the purpose of developing this guideline – at three Technical Consultations between October 2015 and March 2016.

To ensure that each recommendation is correctly understood and applied in practice, the context of all context-specific recommendations is clearly stated within each recommendation, and the contributing experts provided additional remarks where needed.

In accordance with WHO guideline development standards, these recommendations will be reviewed and updated following the identification of new evidence, with major reviews and updates at least every five years.

Further information on procedures for developing this recommendation are available here.

 

Recommendation question

For this recommendation, we aimed to answer the following question:

For pregnant women (P), what diagnostic criteria (I) should be used to distinguish between GDM and diabetes in pregnancy (C) to improve maternal and perinatal outcomes (O)?

 

Evidence summary

Further information and considerations related to this recommendation can be found in the 2013 WHO guideline, available at: http://www.who.int/diabetes/publications/Hyperglycaemia_In_Pregnancy/en/

 

Implementation considerations

  • The successful introduction of evidence-based policies related to antenatal care into national programmes and health care services depends on well-planned and participatory consensus-driven processes of adaptation and implementation. These processes may include the development or revision of national guidelines or protocols based on this recommendation.
  • The recommendation should be adapted into locally-appropriate documents and tools that are able to meet the specific needs of each country and health service. Modifications to the recommendation, where necessary, should be justified in an explicit and transparent manner.
  • An enabling environment should be created for the use of this recommendation, including changes in the behaviour of health care practitioners to enable the use of evidence-based practices.
  • Local professional societies may play important roles in this process and an all-inclusive and participatory process should be encouraged.
  • Antenatal care models with a minimum of eight contacts are recommended to reduce perinatal mortality and improve women’s experience of care. Taking this as a foundation, the GDG reviewed how ANC should be delivered in terms of both the timing and content of each of the ANC contacts, and arrived at a new model – the 2016 WHO ANC model – which replaces the previous four-visit focused ANC (FANC) model. For the purpose of developing this new ANC model, the ANC recommendations were mapped to the eight contacts based on the evidence supporting each recommendation and the optimal timing of delivery of the recommended interventions to achieve maximal impact.

 

Research implications

The GDG identified these priority questions related to this recommendation.

  • What is the prevalence of GDM and diabetes mellitus in pregnancy, according to the new criteria, in various populations and ethnic groups?
  • What are the best screening strategies for GDM and what are the prevalence thresholds at which these are cost-effective?

 

 

Related links

WHO recommendations on antenatal care for a positive pregnancy experience

(2016) - full document and evidence tables

Managing Complications in Pregnancy and Childbirth: A guide for midwives and doctors

Pregnancy, Childbirth, Postpartum and Newborn Care: A guide for essential practice

WHO Programmes: Sexual and Reproductive health

WHO Health Topics: Diabetes

 

 

References

  1. Diagnostic criteria and classification of hyperglycaemia first detected in pregnancy. Geneva: World Health Organization; 2013 (WHO/NMH/MND/13.2; http://www.who. int/diabetes/publications/Hyperglycaemia_In_ Pregnancy/en/, accessed 29 September 2016).
  2. Antenatal care for uncomplicated pregnancies: clinical guideline [CG62]. United Kingdom: National Institute for Health and Clinical Excellence; 2008 (updated 2016) (https:// www.nice.org.uk/guidance/cg62, accessed 30 September 2016).
  3. Ali S, Dornhorst A. Diabetes in pregnancy: health risks and management. Postgraduate Medical Journal 2011; 87(1028):417-427.
  4. Yogev, Chen, Hod, Coustan, Oats, McIntyre et al. Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study: preeclampsia. American Journal of Obstetrics and Gynecology 2010; 202(3):255-257.
  5. WHO handbook for guideline development, 2nd edition. Geneva: World Health Organization; 2014 (http://www.who.int/kms/handbook_2nd_ ed.pdf, accessed 6 October 2016).
  6. GRADE [website]. The GRADE Working Group; 2016 (http://gradeworkinggroup.org/, accessed 27 October 2016).
  7. GRADE-CERQual [website]. The GRADECERQual Project Group; 2016 (https://cerqual. org/, accessed 27 October 2016). 17. DECIDE [website].
  8. The DECIDE Project; 2016 (http://www.decide-collaboration.eu/, accessed 27 October 2016).

 

Citation: WHO Reproductive Health Library. WHO recommendation on the diagnosis of gestational diabetes in pregnancy. (December 2016). The WHO Reproductive Health Library; Geneva: World Health Organization.