MedicalResearch.com Interview with:
Mr Peter Tennant
Research Associate (Epidemiology)
Institute of Health & Society,
Baddiley-Clark Building, Richardson Road,
Newcastle upon Tyne, NE2 4AX.
MedicalResearch.com: What are the main findings of the study?
Answer: For women with type 1 or type 2 diabetes, the prevalence of stillbirth or late miscarriage (3%) was around four times greater than in women without the condition, while the risk of their infant dying during the first year of life (0.7%) was nearly twice as high. There was no difference in risk between women with type 1 or type 2 diabetes.
A woman’s blood glucose concentration around the start of pregnancy, estimated from her glycated haemoglobin concentration (HbA1c), was the most important predictor of risk. The risk increased by 2% for each 1mmol/mol (0.1% in traditional DCCT units) increase in HbA1c above the target of 53mmol/mol (7%) recommended by the American Diabetes Association (ADA). If all the women in our study had achieved that ADA target before pregnancy, we estimate that around 40% of the stillbirths, late miscarriages, and infant deaths could have been avoided.
MedicalResearch.com: Were any of the findings unexpected?
Answer: We were quite surprised to find that the association between HbA1c around the start of pregnancy and the risk of stillbirth, late miscarriage or infant death followed a J-shaped pattern. For almost all women, any reduction in their blood glucose levels – even a small one – is likely to be good for their baby. However, our results also suggest that repeated episodes of severe hypoglycaemia may also be harmful.
It was also surprising to see that the risk of stillbirth, late miscarriage, and infant death appeared to be halved in women who took folic acid supplements before pregnancy. We already know that folic acid reduces the risk of certain congenital anomalies, such as spina bifida or cleft lip, which is why women with diabetes are advised to take high-dose supplements of 5 milligrams daily. This finding suggests there may be additional benefits even for babies without these conditions.
Finally, it was disappointing to see that there was no apparent reduction over time in the excess risk of stillbirth, late miscarriage, and infant death; especially considering that – with the right care – most women with diabetes can and will have a healthy baby.
MedicalResearch.com: What should clinicians and patients take away from your report?
Answer: Any woman with type 1 or type 2 diabetes who is thinking of having a baby should seek advice, as early as possible, from their diabetes team, who can help them to improve their blood glucose control. Even if they can’t manage to achieve the target of 7%; any reduction in blood glucose concentration towards that level is likely to be good for their baby.
All women with diabetes should also try to take 5mg of folic acid per day for at least three months before trying to get pregnant.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Answer: In highly specialised settings, women with diabetes can be helped to achieve similar outcomes to those without the condition, one of the goals of the 1989 St Vincent Declaration. Our study shows that in the general population – of the North of England, at least – this goal appears no closer to becoming reality.
The next step, therefore, is to try and understand and address whatever barriers are preventing women with diabetes from achieving an ideal preparation for pregnancy.