Overview
Gestational diabetes and gestational weight gain
Gestational diabetes mellitus is diabetes that can develop during pregnancy. It affects women who did not have diabetes before pregnancy and usually goes away after giving birth. Women with gestational diabetes have high blood sugar and need to take extra care of themselves and their unborn baby by eating well and keeping active1.
Gestational diabetes is an increasing public health challenge, affecting approximately one in seven pregnancies globally2. It can cause both immediate and long-term health complications, importantly gestational diabetes is linked with significantly increased risk of developing early heart disease and type 2 diabetes3.
Gestational weight gain is the weight a woman gains during pregnancy, which enables the healthy growth of the baby and preparation for breastfeeding. Putting on too much weight during pregnancy (excessive gestational weight gain) can affect a woman’s long-term health as well as increase her risk of developing complications during pregnancy.
Gestational diabetes risk factors
Gestational diabetes risk factors include, but are not limited to:
Weight and BMI: Women who start pregnancy with a higher Body Mass Index (BMI) are more likely to experience excessive gestational weight gain as well as gestational diabetes.
Maternal age: Advanced maternal age (typically >35 years of age) often coincides with a higher risk of developing gestational diabetes, requiring closer monitoring and proactive management throughout pregnancy.
Ethnicity: Various factors tied to ethnicity, including genetic predisposition, cultural influences, lifestyle, and socioeconomic disparities, impact a woman’s gestational diabetes risk. Women of Middle Eastern, North African, Indigenous/Torres Strait/Pacific Islander and Asian ethnicities typically have higher risk of developing gestational diabetes.
Family history of type 2 diabetes mellitus (T2D): Shared lifestyles, genetic factors and environments within families can lead to insulin resistance and impaired glucose regulation. They collectively contribute to increased excessive gestational weight gain and gestational diabetes risk. First-degree relatives carry the highest risk e.g. parent or sibling.
A larger than average baby (≥4000g birth weight) is called macrosomia. It occurs when a woman with gestational diabetes has high blood glucose levels, the glucose will cross the placenta and go straight to the baby. The high amounts of glucose force the baby to make more insulin to process the excess energy, which leads to increased fat and body growth, ultimately a larger baby. Macrosomia can make vaginal delivery difficult, increasing the likelihood of a caesarean birth5.
Shoulder dystocia occurs when one or both of the baby’s shoulders get stuck inside a woman’s pelvis during childbirth. This is more likely to happen when a baby is macrosomic, the woman’s pelvis is very small or the baby’s birth position is not normal. There is a high risk of severe complications for both mother and baby if the vaginal delivery proceeds so emergency caesarean section is commonly performed to reduce these risks6.
Pre-eclampsia is a pregnancy complication characterised by high blood pressure and protein in the urine, usually appearing after 20 weeks of gestation. It can also cause swelling, headaches, vision changes, and pain in the upper abdomen. If severe, it can be dangerous for both the mother and baby. Babies born prematurely may also require admission to a neonatal intensive care unit (NICU) or a special care nursery for comprehensive monitoring 7. Gestational hypertension is when a woman develops high blood pressure in pregnancy without the additional symptoms of pre-eclampsia. This is monitored closely as it can develop into pre-eclampsia and also means the woman is at a greater long-term heart disease risk.
The relationship between gestational diabetes and type 2 diabetes is significant. Women diagnosed with gestational diabetes are ten times more likely to develop type 2 diabetes than those without diabetes in pregnancy3. Children born to mothers with previous gestational diabetes are at higher risk of developing overweight, obesity and diabetes8.
Prevalence of gestational diabetes, IDF 2024
Identification and management
Countries typically use their own clinical practice guidelines because populations differ in terms of risk and the healthcare systems. Healthcare professionals use these guidelines to identify and manage gestational diabetes.
Guidelines for gestational diabetes include:
- universal screening of all pregnant women using the 75g oral glucose tolerance test (OGTT) to check for high blood glucose (24-28 weeks pregnant) or screening women using risk factors and a blood test.
- after diagnosis, management will include blood glucose monitoring, regular maternal/foetal monitoring, diet and lifestyle alterations, potentially medications, and a repeat OGTT at 6-8 weeks postpartum and then annual diabetes screening going forward.
Reducing risk during pregnancy and in the longer-term
Lifestyle interventions of healthy eating and physical activity delivered by healthcare professional either during pregnancy or postpartum can reduce excessive gestational weight gain, gestational diabetes risk, and postpartum weight retention, but most interventions typically focus only on one life stage and have limited implementation in routine care.
Mobile health (mHealth) interventions offer potential to overcome barriers to participation such as time constraints and travel requirements, but evidence for their effectiveness spanning the pregnancy-postpartum continuum is limited.