Navigating Gestational Diabetes
Gestational diabetes mellitus (GDM) is an often misunderstood aspect of antenatal care and with routine testing it can be hard to know what is suggested by the hospital system and whether or not it is something you actually need to be worried about. With varying diagnostic approaches for GDM and treatment recommendations across different countries, it’s essential to delve into the evidence and understand what truly benefits maternal and infant health.
Testing Strategies for Gestational Diabetes
01.
OGTT Comparison
One trial comparing 75 g and 100 g OGTT found a higher GDM diagnosis rate with the 75 g test (RR 2.55, very-low quality evidence).
02.
Sweets vs. Glucose Drink
A trial of 60 women found a preference for the taste of the chocolate bar and lower 1-hour glucose levels, with no significant difference in side effects.
03.
Glucose Polymer vs. Monomer Drink
Three trials (239 women) reported fewer side effects and less nausea with the polymer drink, but taste preference was unclear.
4.Glucose in Food vs. Drink
One trial (30 women) indicated fewer side effects with glucose in food form
5.Two-step vs. One-step Approach
One trial (726 women) found a lower GDM diagnosis rate with the two-step approach (RR 0.51).
The conclusion? There is insufficient evidence to declare a better strategy. Large randomised trials are necessary to determine the most accurate and cost-effective method for diagnosing GDM. However, the question needs to be asked of why are we trying to label pregnant women?
Global Perspectives on GDM Treatment
Around the world, treatment for GDM varies significantly:
- Australia: The adoption of the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria has increased diagnosis rates, but outcomes haven’t necessarily improved.
- UK: Treatment focuses on reducing serious health issues like stillbirth and neonatal hypoglycemia.
- US: Emphasis is placed on rapid treatment to prevent severe complications such as seizures, nerve injuries, and stillbirth.
Despite these rigorous approaches, evidence supporting the efficacy of pharmacological treatment is limited. Most interventions, particularly those involving medication, lack a strong foundation of benefit and safety.
The Impact of Treatment on Babies and Mothers
Evidence suggests that treatment for GDM doesn’t significantly improve outcomes. Here’s what we know:
- Birthweight Reduction: Treatment can reduce birthweight by an average of 110 g, mostly affecting lean mass rather than fat.
- Hypertension: Some reduction in maternal hypertension is noted, likely due to weight control rather than glucose management.
- Perinatal Mortality and Future Diabetes: Glucose levels short of diabetes don’t increase perinatal mortality, and treatment doesn’t reduce it.
For mothers, the diagnosis of GDM often leads to increased medical interventions, heightened anxiety, and significant lifestyle disruptions. Frequent blood tests, medication, and dietary restrictions can add to the stress, impacting both physical and mental well-being.
Moving beyond the label
The term “gestational diabetes” often leads to over-medicalisation of pregnancy. Women labeled with GDM are typically directed into specialised care, facing stigma and restricted birth choices. However, care should be tailored based on what a woman needs during her pregnancy rather than the labels assigned to her.
In the end..
Gestational diabetes is a condition with significant variations in diagnosis and treatment worldwide. Women deserve accurate information to make informed decisions about testing and treatment. Evidence suggests that many current practices do not significantly benefit mothers or babies, emphasising the need for caution when applying labels to women who are pregnant and, evidence-based approaches.
When engaging with any testing in pregnancy ask yourself what the outcomes might be and what you are willing to do about it? Are you going to engage with the suggested interventions? And where is that line in the sand for you and your family?
Additional reading:
1. Wickham, S. (n.d.). "Gestational Diabetes." Retrieved from (https://www.sarawickham.com/articles-2/gestational-diabetes/).
2. Olza, I. (2019, September 2). "Big Babies: The Risk of Care Provider Fear." Retrieved from https://midwifethinking.com/2019/09/02/big-babies-the-risk-of-care-provider-fear/
3. McLean, K. (2020, February 12). "New Call to Review Gestational Diabetes Screening." Retrieved from https://www1.racgp.org.au/newsgp/clinical/new-call-to-review-gestational-diabetes-screening fbclid=IwZXh0bgNhZW0CMTAAAR0DZF3gKad5et3clvlIq5_KPcrBllGO1ZJVxkS5QfAzhJcEHTDPJEvea0A_aem_AfYM9MVMhk5C514Ei_IGp1azYOq86AZwrsUuv57sh2F-PZplzvxKtpQQckcz7bnjWmGL6ak4xzgyn86oh6cLhnUg
4. Xu, H., et al. (2020). "Maternal and neonatal outcomes of women with gestational diabetes and without specific medical conditions: An Australian population-based study comparing induction of labor with expectant management." Retrieved from https://obgyn.onlinelibrary.wiley.com/doi/10.1111/ajo.13505
5. Dekker, R. (2019, March 15). "Does Gestational Diabetes Always Mean a Big Baby and Induction?" Retrieved from https://evidencebasedbirth.com/does-gestational-diabetes-always-mean-a-big-baby-and-induction/?fbclid=IwZXh0bgNhZW0CMTAAAR1D-ewIh3ueDmBwffVdTHCrLLHoo5WZW4PIdWqBX1pYrfYeZlp75XJtvIQ_aem_AfY4V5yjbpBKDfGt5rZP3niP83T1_yLJ4mc8f3zcEuOHJjNbx5eRfW8moZI35ysfeS2ybtUyKoFTPqLD8RyHHlrt
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