If gestational diabetes goes undetected, or is not managed effectively, it can cause complications for both you and your baby.
Controlling your blood glucose (sugar) levels throughout your pregnancy reduces the risk of complications.
Gestational diabetes may increase the risk of:
- placental abruption – the placenta (the organ that links the pregnant woman’s blood supply to her unborn baby’s) starts to come away from the wall of the womb (uterus). This may cause vaginal bleeding and/or constant abdominal pain
- needing to induce labour – when medication is used to start labour artificially (read about inducing labour for more information)
- premature birth (see below)
- macrosomia (see below)
- trauma during the birth – to yourself and your baby
- neonatal hypoglycaemia – your newborn baby has low blood glucose, which can cause poor feeding, blue-tinged skin and irritability
- perinatal death – the death of your baby around the time of the birth
- development of obesity and/or diabetes later in the baby's life
Premature birth
Gestational diabetes can cause premature birth (your baby being born before week 37 of the pregnancy). This can lead to further complications for your baby, such as:
- respiratory distress syndrome – your baby’s lungs are not fully developed and cannot provide enough oxygen to the rest of their body
- jaundice – your baby’s skin turns yellow when a waste product called bilirubin builds up in the blood
Macrosomia
Gestational diabetes increases the risk of your baby being large for its gestational age, i.e. weighing more than 4kg (8.8lbs). This is known as macrosomia.
Macrosomia occurs during the pregnancy because the excess glucose in the mother’s blood is passed to the foetus (unborn baby). This causes the foetus to produce insulin (a hormone) that allows glucose to enter the cells, which results in growth.
Shoulder dystocia
Macrosomia can lead to a condition called shoulder dystocia. This is when your baby’s head passes through your vagina, but your baby’s shoulder gets stuck behind your pelvic bone (the ring of bone that supports your upper body, also called the hip bones).
Shoulder dystocia can be dangerous as your baby may not be able to breathe while they are stuck. It is estimated to affect 1 in 200 births. For more information, see Royal College of Obstetricians and Gynaecologists: shoulder dystocia.
Future conditions
Mother
After having gestational diabetes, you are around seven times more likely to develop type 2 diabetes than women who have had a normal pregnancy.
Type 2 diabetes is when your body does not produce enough insulin, or the body’s cells do not react to the insulin (insulin resistance). read about type 2 diabetes for more information about this condition.
Therefore, it is important your blood glucose is monitored after the birth to check whether or not it returns to normal.
Baby
Your baby may also be at greater risk of developing these conditions in later life:
- diabetes
- obesity (having a body mass index of more than 30)
Future pregnancies
After having gestational diabetes, you are at increased risk of having gestational diabetes in any future pregnancies.
It is very important to speak to your GP if you are planning another pregnancy. They may arrange for you to monitor your own blood glucose from the early stage of your pregnancy. Read about diagnosing gestational diabetes for more information