Dr Claire Meek will be speaking at our upcoming symposium for health professionals, Screening for GDM – are we getting it right?  She talks to ZOE DELEUIL about her recent research around screening for gestational diabetes. 

Q: We know that Australian women are increasingly declining the oral glucose tolerance test. Is this also the case in the UK, and why do you think that might be? 

A: The OGTT is a difficult, unpleasant test, and there can be many reasons that women don’t attend their appointment. For some it can be an equity issue – they might be a single parent with work and caring responsibilities, or they might not have family support. And while of course we don’t have the rurality that you have in Australia, it can still be some distance to travel to a hospital. We do find that some women will come for the OGTT after a second invitation.  

Q: What are some alternatives to the OGTT? Are some women instead choosing to monitor their blood glucose level with CGMS, for example?

A: There’s been a lot of interest in an at-home test, and it has some major advantages in that it doesn’t need a sample to travel to the lab, so it improves accuracy, and it’s much more convenient – you could do it at home on a Saturday morning, for example. The only problem is the expense – it increases the number of diagnoses, which potentially increases the cost of it in your health system.  

I see the CGM (continuous glucose monitor) as a self-management rather than a diagnostic tool. And of course, it’s a lot more expensive, so it’s not going to be suitable for everyone. In general, the OGTT is a better choice.  

Q: Your research shows that the OGTT test can result in false negatives because the red blood cells in the sample consume the glucose before it reaches the lab for testing. How did you know this might be happening, given that, by their nature, missed gestational diabetes diagnoses are invisible? 

A: It’s been known for some time in clinical biochemistry circles that processing speed and time makes a difference to the amount of glucose in a blood sample.  

What we didn’t know was the extent of those misdiagnoses in real life. I was fully expecting we would be missing some cases of gestational diabetes. I did not expect it to be half. That was quietly devastating. 

Q: What was the response to this discovery in the UK? 

A: We were slightly disappointed in the pickup in the UK. Everyone was like, we’ve already got too much work to do. 

You might assume that those women who were missed would only have slight elevations in their blood glucose levels, but we found that wasn’t necessarily true. Some women actually started with very high levels and ended up with normal levels by the time their test was processed. So, we are spending money doing tests that are not really meeting the need.  

And of course, timely GDM diagnosis is so important in preventing type 2 diabetes. You lose a real opportunity to engage with the longer-term health of that woman if their GDM is missed. This is something we need people to engage with. 

Q: What do women miss out on, in terms of care and support, if their gestational diabetes is missed?  

A: We find that the women who were not diagnosed, but had glucose levels consistent with GDM, had a higher rate of a large baby, almost 40%. This increased the rate of C-sections, many of which were preventable. Also, those women missed out on a bit more warning and choice about how their baby was delivered.  

There is also a conversation to be had about the longer-term health of those babies – do they have higher risk of diabetes or childhood obesity? Do the glucose levels you’re exposed to in the womb have an impact on your later health?  

Q: And presumably women whose GDM is not diagnosed will miss out on extra support throughout the pregnancy? 

A: Women do get a lot more contact with the health system when they have GDM, and there are benefits in terms of more support, more visits from health visitors, a closer eye in terms of safeguarding. There are potentially a lot of benefits. Having your first baby is a huge shock as it is, so we need to know when a woman also has GDM.  

Q: Another assumption you’ve said you want to gently challenge is that GDM ends with the pregnancy. How does more support beyond pregnancy and delivery make a difference to a woman’s long-term health outcomes?  

A: Dietary information and support during GDM help women during pregnancy, but long-term dietary changes can be harder, particularly if you are also breastfeeding, recovering from birth and not able to move or exercise much.  

Women may be highly motivated to set healthy practices, but that combination of no sleep, the huge demands of motherhood and potentially less income during the post-natal period can all make it harder to adopt a healthier lifestyle.   

Part of our work is saying that the support for women with GDM needs to go on for longer, particularly as many women will come back and have another pregnancy. By offering more support in the six months after the birth, you can do a lot of good to help prevent type 2 diabetes, and even GDM the second time around. 

Dr Claire Meek is Professor of Chemical Pathology and Diabetes in Pregnancy at Leicester Diabetes Centre. She runs the diabetes in pregnancy service at University Hospitals Leicester, which includes a large, ethnically and socioeconomically diverse cohort of women with early onset type 2 diabetes (EoT2D). She runs observational and interventional studies to improve clinical outcomes for women with diabetes in pregnancy. 

Are you a health professional interested in learning more about the current challenges, research and innovations in screening for gestational diabetes?

Come along to our symposium for health professionals, Screening for GDM – are we getting it right?  on August 18, 2025, where we will hear from Dr Claire Meek and other leading voices in the field of GDM research and healthcare. 

We will explore the need to improve the GDM screening process, the experience for mothers and clinical outcomes.

Visit our website to find out more about our guest speakers and partners and to book your place for an insightful evening of discussion.