The subject was gestational diabetes, or ‘GDM’, which develops during pregnancy and affects one in eight expectant mothers in Ireland.
Diabetes (including GDM) is characterised by high blood glucose due to a shortage of the hormone, insulin. This is often accompanied by elevations in blood-fat levels. Both of these abnormalities increase the long-term risk of heart disease and stroke. Also, poorly controlled diabetes can increase the risk of cancer. We need to consider the long-term health consequences of GDM for the mother and the developing baby.
Women who develop diabetes in pregnancy are much more likely to develop long-term, type 2 diabetes afterwards.
The Atlantic-DIP study, in the West of Ireland, indicates that three in ten Irish women with gestational diabetes will have pre-diabetes or type 2 diabetes within three years of delivery.
These women, who develop diabetes in their 20s or 30s, may be experiencing serious health consequences as they enter their 50s and 60s, given the cumulative, damaging effect of the condition over time.
The health implications of gestational diabetes for the developing foetus are also pertinent. In the short-term, pregnancy complications, including high blood pressure, prematurity and caesarean delivery, as well as neonatal problems, such as low blood sugar and breathing difficulties, are all increased in GDM. GDM babies are larger at birth, and have more fat and less muscle than babies born to non-diabetic mothers.
These differences, while seeming subtle, have long-term health implications for the baby, with research suggesting an increased risk of obesity, diabetes, heart disease and stroke in adulthood.
The marked increase in GDM in Ireland is the result of converging risk factors. Firstly, the prevalence of overweight and obesity among women of reproductive age in this country is 50%, having risen substantially in recent years.
Secondly, Irish women are waiting longer to have their children, with average maternal age now well over 30.
This is important, as diabetes prevalence increases in all populations as they age.
So, what can be done to treat this condition and prevent its consequences? The first priority is to increase awareness of the condition among women of child-bearing age.
The blood test for GDM is not a routine part of obstetric care. If you’re at increased risk of the condition, for example, if you are an older mother (over 35 years), or are carrying extra weight, or have a history of polycystic ovarian syndrome or a family history of diabetes, then you can ask your GP to test you.
Fortunately, in the event that GDM is diagnosed, more than two thirds of women can control their blood-sugar and blood-fat levels sufficiently by taking additional exercise, and making appropriate dietary changes — cutting out sugary foods, especially sugary drinks, and the inclusion of additional, oily fish (e.g. sardines).
For some women, however, their GP may prescribe tablets to get their GDM under control, as the normalisation of blood sugar and blood-fat levels is the key priority.
While GDM poses risks, it does present a window of opportunity for women to optimise the health of their baby, if detected sufficiently early and managed effectively.
Critically, however, a diagnosis of GDM can act as a early warning, prompting women to make the long-term diet and lifestyle changes required to alleviate their own risk of developing type 2 diabetes, and its adverse consequences in later life.
* Dr Daniel McCartney, lecturer in human nutrition and dietetics at DIT