Newcastle University

Researchers at Newcastle University, who led the study, have warned pregnant women with diabetes that it is important they control their blood glucose levels. Their study funded by Diabetes UK, suggests that as many as one in 13 deliveries to women with Type 1 or Type 2 diabetes involves a major congenital anomaly, also known as a birth defect.

But the researchers and Diabetes UK have emphasised that, while concerning, this still means that the vast majority of pregnancies in women with diabetes do not involve a birth defect.

The study also showed that blood glucose levels around the time of conception was the most important factor predicting risk of congenital anomaly. 
 
The findings have prompted Diabetes UK to urge women with diabetes who are considering becoming pregnant to make sure they understand the importance of careful planning.  It has also called for the NHS to provide better care for women with diabetes who may be planning to have a baby and for women who are thinking of becoming pregnant to attend a pre-conception clinic if one exists in their area or to ask their GP to put them in contact with a diabetes specialist if not.

Dr Ruth Bell, the study’s lead researcher, said:  "The good news is that, with expert help before and during pregnancy, most women with diabetes will have a healthy baby.  The risk of problems can be reduced by taking extra care to have the best possible glucose control before becoming pregnant.  Any reduction in high glucose levels is likely to improve the chances of a healthy baby.

"All young women with diabetes need to know about preparing for pregnancy, and should contact their doctor or diabetes team as soon as possible if they are thinking about pregnancy or become pregnant."

Previous research has established that having diabetes increases the chance of birth defects, but this is one of the first studies to quantify the effect of glucose levels on risk.  Published in the journal Diabetologia, the study involved an investigation of the recorded outcomes of 401,149 pregnancies, including 1,677 pregnancies in women with diabetes, between 1996 and 2008 in the north of England.

The analysis showed that the risk of a birth defect in the pregnancies of women with Type 1 or Type 2 diabetes was seven per cent, compared to an average of around two per cent in pregnancies where the mother did not have diabetes. The chance of a birth defect was lowest in women who had blood glucose levels within the recommended ranges, which according to Diabetes UK has highlighted the importance of healthcare teams encouraging women who are thinking of becoming pregnant to get their blood glucose level as low as is safely possible.

More information on this story can be read in the full press release.