Gestational diabetes is an increasingly prevalent and costly pregnancy complication worldwide. In fact it is estimated to affect one-in-eight Irish pregnancies, which makes it one of our most common pregnancy complications.¹ Gestational diabetes is associated with increased risk of pregnancy complications such as Caesarean section and shoulder dystocia. However, the longer-term consequences are equally important to consider. 

Women with a history of gestational diabetes are at increased risk for developing type 2 diabetes, obesity and hypertension.² The risk of developing type 2 diabetes is estimated to be one-in-two women developing it within five to ten years after their first gestational diabetes-affected pregnancy.³ This makes these women an important subgroup to work with if we want to bring down population diabetes rates. 

Diabetes prevention is possible and for women with previous gestational diabetes, we know that healthy eating and increased physical activity can reduce risk by 58%.⁴ The challenge with undertaking a diabetes prevention programme in women with previous gestational diabetes is that this subgroup are at a completely different life-stage to the average person at risk of diabetes. These women are usually in their early 30s, have young families and additional primary caregiver responsibilities.⁵

Another important difference is that the women have lived with diabetes during their pregnancy and in some cases, managed it with insulin. This lived experience creates a known emotional toll on women and can create negative associations that may make them less likely to want to address their longer-term diabetes risk.⁶ All of this means that they face different barriers and enablers to behaviour change and that these factors need careful consideration when designing interventions for this population.

Studies on prevention

Over the past five to ten years, the number of intervention studies being reported for women with previous gestational diabetes has grown dramatically. A recent meta-analysis and systematic review has explored these studies to see if interventions in the postpartum period are successful in reducing diabetes risk.⁷

Overall they found that study populations tend to be small and that they are conducted over an average of a six-month timeframe. The study designs were a mixture of interventions as well – some doing dietary and physical activity behaviour change and others doing either diet or physical activity. The methods used to deliver the interventions was also very varied – in person, in groups, using a website, providing written material, using an app and/or a mixture of methods. 

The study identified that engaging with women early on in the postpartum period and having a longer follow-up duration (about 12 months) had positive influences on diabetes risk reduction.⁷ In essence, starting and building a relationship and a system to support effective behaviour change is an important piece of the puzzle to reduce a woman’s risk of developing diabetes after pregnancy.

Mothers After Gestational Diabetes in Australia (MAGDA)² was a large-scale partnership project that happened between 2010-2016 and took a systems approach to the prevention of type 2 diabetes in women with previous gestational diabetes. The work was funded by the Australian National Health and Medical Health Research Council in partnership with Diabetes Australia and two state Departments of Health (Victoria and South Australia). MAGDA comprised three main studies. 

The first study looked at the impact of the National Gestational Diabetes Register (NGDR). The NGDR is unique internationally as it is a national-level register that sends reminder letters to women for their six- to eight-week postnatal diabetes screening and annual follow-up by their GP. The study was able to examine the NGDR performance by comparing its data with the related State perinatal data collection and independent pathology laboratory data. The study analysed data over a two-year period.⁸

The results showed that the universal screening process during pregnancy was working well, with around 97% women undertaking the oral glucose tolerance test at the appropriate time. The NGDR registration rate was also good at 91%. However, postpartum screening rates did not change after the NGDR was introduced,⁸ which meant that, disappointingly, none of the reminder letters made any difference to follow-up diabetes screening rates.

The second study looked at the impact a diabetes prevention programme specifically designed to meet the needs of a postpartum mother could have on diabetes risk. This was a randomised clinical trial of a six-session group-based diabetes prevention programme with 573 women who started the programme during their first postpartum year.⁹

The intervention resulted in weight stability, whereas the women receiving usual care continued to gain weight (mean change [intent-to-treat analysis] over 12 months being -0.95kg between groups; p = 0.04). Another key finding was that engaging women in a face-to-face programme was challenging and as a result, the intervention was adapted to be delivered using telephone health coaching and a mobile application.^10,11 Both of these formats were well received and for the telephone one, increased average weight loss to 2kg.¹⁰ This points to women being able to engage in diabetes prevention when the intervention is designed to fit within their busy lives. 

The third study was a 12-month quality improvement collaboration involving 15 general practices, which engaged in establishing practice-based registers and recall systems for blood testing, and type 2 diabetes prevention planning consultations.¹² The quality improvement process involved forming an expert advisory group, developing a handbook for the quality improvement, delivering a workshop online for practices every three months and collecting ‘plan-do-study-act’ cycle reports and audit measures. 

The intervention doubled the review and testing of women (from 30% to 60% over 12 months) and increased measurement of BMI (from 51% to 69% over 12 months), but the uptake of specific type 2 diabetes prevention planning consultations was low (10%).¹² The key components that drove the uptake of the intervention were: 

• Seeing the care of women as a central practice activity
• Taking a long-term community perspective on health and wellbeing
• Staff engagement in creating the quality improvement together
• Performing and acting on audit feedback. 
• Delivering an intervention at the level of a general practice means that this intervention has potential to be scaled up and improve diabetes prevention activity at a national level.

Big-picture perspective

Looking at the three studies together as parts of a system-level intervention enables a ‘big picture’ perspective to be taken. Australia’s universal screening programme for diabetes in pregnancy is working well but it is outside the controlled hospital environment that the diabetes screening processes and messaging need more work. 

Diabetes prevention programmes need to be seen as relevant and accessible in order for people to use them. We know from MAGDA that women will engage with a diabetes prevention service if it can fit within their busy lifestage. 

General practice is a place where diabetes prevention could be driven from. Women regularly visit their GP and the practice can potentially marry the diabetes prevention activity with the normal care delivered. General practices are also in a unique position that they can share the results of that activity with the health service or a national register. 

The MAGDA research team and I were recently successful in receiving further Australian Government funding to improve the messaging behind the NGDR screening initiative and also extend the delivery of the diabetes prevention intervention described above. This and other work currently being done in Ireland and internationally will all add more pieces to the puzzle on how we prevent diabetes in women with previous diabetes. We don’t have the answer just yet, but watch this space! 

Main findings

• Healthcare professionals need to build relationships with women during and after pregnancy to foster behaviour changes over time
• Reminder and recall letters do not appear to work, but using a national gestational diabetes register to populate family practice-based registers may be more successful at stimulating diabetes screening activity
• A low-dose intervention can halt progressive weight gain for women at high risk of developing type 2 diabetes.

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