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Speaking at the American Diabetes Association's 84th Scientific Session, new authors of the Lancet series question current approaches to managing gestational diabetes (a type of diabetes diagnosed during pregnancy) and call for starting treatment earlier to prevent complications during pregnancy and beyond.
- Gestational diabetes mellitus (GDM), commonly referred to as gestational diabetes, is the most common pregnancy complication worldwide, affecting one in seven pregnancies (14%). Cases of GDM are increasing worldwide and are complicated by rising risk factors such as obesity.
- If left untreated, gestational diabetes can lead to health complications such as high blood pressure, increased risk of Caesarean section, mental illness, complications for the baby during birth, and even type 2 diabetes and cardiovascular disease later in the mother's life.
- Recent evidence suggests that the foundations for developing GDM are laid before pregnancy and that metabolic changes are often detected early in pregnancy (before 14 weeks), although testing and treatment for GDM usually only occurs later in pregnancy (24-28 weeks).
- The authors call for the urgent implementation of strategies to prevent and manage GDM throughout a woman's life, including early screening and diagnosis to reduce pregnancy and birth complications and reduce the risk of developing other health conditions later in life.
Shifting screening and management of gestational diabetes mellitus (GDM) to earlier in pregnancy (before 14 weeks) can prevent health complications for both mother and baby, according to a new series published in 2010. LancetThe series authors challenge the current approach to GDM management, which focuses on the later stages of pregnancy (24 weeks or more), and call for better detection and prevention efforts, as well as an individualized, integrated life course approach for those who have experienced GDM or are at risk for GDM.
GDM, also known as gestational diabetes, is a type of diabetes during pregnancy in which blood glucose levels are higher than average but not as high as diabetes, and is the most common pregnancy complication worldwide, affecting one in seven pregnancies (14%). As obesity and other metabolic diseases continue to rise worldwide, some abnormal blood glucose/insulin regulation is becoming more prevalent among women of reproductive age, not only increasing the risk of pregnancy complications, but also leading to health conditions later in life such as type 2 diabetes (T2D) and cardiovascular disease.
“Our new series highlights the urgent need for significant changes in how GDM is diagnosed and managed, not just during pregnancy but throughout the lifespan of mothers and babies,” said Professor David Symons from Australia's Western Sydney University, who is leading the series. “GDM is an increasingly complex disease and there is no one-size-fits-all approach to its management. Instead, patients' unique risk factors and metabolic profiles must be taken into account to help guide them throughout pregnancy and support them beyond, ensuring the best health outcomes are achieved for women and babies around the world.”
As obesity continues to rise worldwide, and as rates of impaired glucose tolerance and type 2 diabetes increase in women of reproductive age, the prevalence of GDM has also increased two- to three-fold in several countries over the past two decades. The current prevalence of GDM is over 7% in North America and the Caribbean and almost 28% in the Middle East and North Africa.
Between 30% and 70% of women with GDM experience high blood sugar (hyperglycemia) beginning early in pregnancy (before 20 weeks of pregnancy, also known as early GDM). These women have poorer pregnancy outcomes compared to women whose GDM does not manifest until later in pregnancy (24-28 weeks). In studies where GDM was not adequately managed, even in later pregnancy (e.g., insulin was not used when needed), GDM was associated with an increased risk of cesarean section (16%), preterm birth (51%), and large-for-gestational age babies (57%). Other studies looking at GDM pregnancies requiring insulin therapy have found a more than two-fold increased risk of neonatal intensive care unit admission.
Women diagnosed with GDM have a 10 times higher risk of developing T2D later in life compared to women who don't have GDM. They are also more likely to suffer from hypertension, dyslipidemia (high blood lipid levels), obesity and fatty liver, and have a two times higher lifetime risk of developing cardiovascular disease.
Women with GDM are at increased risk of mental disorders such as stress, depression and anxiety, and also experience stigma, guilt and shame associated with GDM during pregnancy. As well as the impact of guilt and shame themselves, guilt and shame can lead to further negative outcomes if patients avoid testing their blood glucose or taking insulin due to guilt or shame.
Recent studies suggest that a diagnosis of GDM may be associated with an increased risk of subsequent postpartum depression. Conversely, treatment of late GDM is associated with lower rates of depression at 3 months postpartum, and treatment of early GDM is associated with improved quality of life at 24-28 weeks gestation.
“GDM is a major public health challenge. Women experiencing GDM need support from the medical community, policymakers and society at large to ensure they can effectively access appropriate treatment, reduce the stigma associated with GDM and improve their overall pregnancy experience.”
Dr. Yashdeep Gupta, Series Author, All India Institute of Medical Sciences
GDM has historically been considered a pregnancy complication involving treatment of hyperglycemia in the second and third trimesters, and the World Health Organization's current criteria for diagnosing GDM recommend testing at 24–28 weeks' gestation without prior screening.
However, recent evidence suggests that GDM may have an underlying condition before conception and may develop during early pregnancy. Overall, 30-70% of cases of GDM can be detected early with an oral glucose tolerance test, including those at highest risk of needing insulin therapy or experiencing pregnancy complications.
Recent studies, such as the TOBOGM RCT, have shown that for women with early GDM, diagnosis and treatment before 20 weeks of pregnancy (vs. 24-28 weeks) not only reduces pregnancy and postpartum complications such as neonatal respiratory distress and length of stay in the neonatal intensive care unit, but also improves quality of life during the second trimester, increases breastfeeding initiation, and reduces the likelihood of developing obesity, type 2 diabetes, and other long-term diseases.
“The benefits of early GDM detection are clear – it can help keep mother and baby healthy during pregnancy and hopefully for life. What is needed now is earlier testing and ways of managing GDM that take into account available resources, the situation and the patient's personal preferences,” says series author Dr Helena Backman of Örebro University in Sweden.
A better understanding of GDM and its consequences will enable researchers, clinicians, and policymakers to develop new management approaches focused on improving the prevention and treatment of GDM complications, from before, through pregnancy, and beyond.
Recommended strategies developed by the series authors include:
- For those with risk factors, early GDM testing is performed, ideally before 14 weeks of pregnancy.
- Promoting health at a population level, particularly for women with risk factors, to prepare for healthy pregnancies and subsequent healthy aging.
- Improve prenatal care, including postnatal glycemic screening.
- For women who have previously had GDM, we provide tailored annual assessments to prevent or better manage complications such as T2D (especially in subsequent pregnancies) and cardiovascular disease.
- Further research into GDM and ways to improve lifelong outcomes for women with GDM and their children.
“It is past time to move from 'late pregnancy' focused services to tailored life course strategies that are integrated in both high and low resource settings. This includes new systematic approaches to prevention, early treatment of GDM, identifying and overcoming barriers to uptake, better health systems integration and further research to better understand how GDM affects women and their children during pregnancy and throughout their life,” Professor Symons said.