Lloydspharmacy.com Health - Pregnancy and diabetes

Reviewed by Professor Ian Campbell, consultant physician

Good blood sugar control is key to a healthy pregnancy.

Most women with diabetes who become pregnant have Type 1 diabetes (insulin-dependent diabetes), because this is the type that affects younger women. However, increasing numbers of pregnant women with Type 2 diabetes (non-insulin dependent diabetes) are being seen.

If you have diabetes and want to start a family, there are a number of things to consider. The key to a healthy pregnancy with diabetes is good blood sugar control before, during and after pregnancy.

What are the risks?

Babies born to mothers with poor blood sugar control are more likely to have birth defects or be stillborn.

Babies born to mothers with diabetes weigh more than average, especially if glucose control has been poor.

For the mother, diabetes and pregnancy can be associated with extra risks. Retinopathy may increase in severity.

Diabetic kidney disease increases your chance of developing high blood pressure and a more serious condition called pre-eclampsia that can affect mother and baby.

What can I do to reduce these risks?

Establishing good glucose control well before conceiving and throughout pregnancy reduces the chance of all these problems occurring. Pre-pregnancy counselling by a specialist hospital diabetes clinic should be available.

A combined approach between you, your GP, nurses, eye specialist and obstetrician is the best way to minimise problems.

Regular blood sugar checks are essential to keep track of the diabetes, because your insulin requirement will increase as your pregnancy develops.

This is caused by the increasing demands of your growing baby combined with the natural tendency for insulin resistance to increase in all pregnancies.

All this means you will probably need to test your blood sugar level more frequently during pregnancy. This will be at least four times per day before meals. But, increasingly, between-meal testing is advised to increase the daily (and sometimes night-time) blood glucose testing to seven or eight times per day.

Does pregnancy affect treatment?

Type 2 oral hypoglycaemic drugs are not recommended in pregnancy.

This means women with Type 2 diabetes should convert to insulin treatment before becoming pregnant.

How does diabetes affect pregnancy and delivery?

From the start of the second trimester (13 weeks onwards), blood pressure and glucose levels can start to increase more rapidly, so need frequent monitoring.

A full-term pregnancy is 40 weeks, but with diabetes labour is often induced (started early) at 38-39 weeks to reduce the risk of stillbirth. As a result, Caesarean section deliveries are more common.

During labour, insulin and glucose are given by drip feeds, adjusted to keep the blood sugar stable.

Most babies born to mothers with diabetes don't require special care, although special attention is given to ensure the baby is not hypoglycaemic at birth.

Until 2008. it was recommended that oral hypoglycaemic agents were not used in pregnancy and it was advised that women with type 2 diabetes should convert to insulin treatment before becoming pregnant.

However, the 2008 NICE guidelines for the management of diabetes from preconception to the postnatal period, state that metformin maybe used for women with pre-existing Type 2 diabetes as an adjunct or alternative to insulin in the preconception period and during pregnancy.

A large trial from Australian and New Zealand in 2008 showed that metformin when compared with insulin was not associated with increased perinatal complications, either to the mother or baby. Additionally, women preferred metformin to insulin.

References
National Institute for Health and Clinical Excellence. Diabetes in pregnancy: management of diabetes and its complications from preconception to the postnatal period. London: NICE, 2008. www.nice.org.uk/CG063.

Rowan JA, Hague WM, Gao W et al. Metformin versus insulin for the treatment of gestational diabetes. New England Journal of Medicine 2008; 358: 2003-15.

Based on a text by Dr Jan Erik Henriksen and Dr Henning Beck-Nielsen, consultant

Last updated 29.09.2008