Pregnancy diabetes, or gestational diabetes mellitus, is most common in the middle and later months of pregnancy.
Pregnancy hormones affect the action of insulin on the body, so it needs to produce more to ensure blood sugar continues to be broken down to be used as energy.
If the body can't produce enough insulin, gestational diabetes occurs. Your blood sugar levels rise and these sugars pass on to your baby, meaning he will grow particularly large.
Most at risk are women who are obese, have had diabetes in a previous pregnancy or have a diabetic parent or sibling. Women from a non-white background are also at increased risk.
Pregnancy diabetes is usually picked up through tests performed by your midwife, so make sure you attend all antenatal checks.
The main risk of gestational diabetes is it can cause your baby to grow very big. This can cause problems at birth, so you may be induced early. Your baby may also require extra feeds after birth, as he will be used to a constant supply of sugar that is no longer available, and his glucose levels may drop.
Do your best to prevent pregnancy diabetes by eating a healthy diet and aiming for 30 minutes of moderate exercise a day.
'If you have pregnancy diabetes, cut out junk food from your diet, reduce your sugar intake and go for wholegrain foods,' advises Kerry Stubbington, a specialist diabetes midwife at Addenbrooke's Hospital in Cambridge.
'Eating little and often keeps blood sugar steady and you'll need to test your blood sugar during the day with a blood sugar monitor. If it can't be controlled by diet, insulin injections will be necessary.'
With close monitoring, a healthy diet and treatment if necessary, there is no reason why you shouldn't go on to have a healthy pregnancy and baby.
In nine out of 10 cases, pregnancy diabetes goes away after the birth, but there is more chance of developing Type 2 diabetes in future.
Recent research funded by Diabetes UK has demonstrated that a wearable artificial pancreas could radically reduce the risks pregnancy poses to women with Type 1 Diabetes. Find out how here...
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