Care recommendations
Folic acid supplementation in pregnancy
Diabetes UK recommends that all women with diabetes take extra folic acid supplements daily, before conceiving and during the first 12 weeks of pregnancy, to reduce the risk of neural tube defects (NTDs) in the unborn child. Most women planning a pregnancy are advised to take 0.4mg (400 micrograms) of folic acid daily to prevent the first occurrence of NTDs.
Extra folic acid (folate) is recommended for all women prior to conception and during the first 12 weeks of pregnancy to reduce the risk of neural tube defects (NTDs). NTDs can occur if the brain and/or spinal cord with its protecting skull and spinal column fail to develop properly around the fourth week of embryonic life.
In the British diet the main sources of folic acid are cereals and green, leafy vegetables. A significant proportion of folic acid is obtained through fortification especially of breakfast cereals.
Women planning a pregnancy are advised to take 400 micrograms (0.4 milligrams) of folic acid daily to prevent the first occurrence of NTDs. This is the level of supplementation recommended by the majority of nations giving guidance to women of childbearing age with no previous history of pregnancies affected by NTDs. Not all NTDs are caused by a folate deficiency.
Women with diabetes are at increased risk of having babies with NTDs. If you are planning a pregnancy and you have diabetes it is crucial that you should discuss preconception care with your diabetes care team. They will want to discuss various issues with you that may affect the outcome of your pregnancy. This might include the potential benefits of taking an increased dose of folic acid compared to other women. Doctors may recommend, for example, that women with spina bifida or who have already had a child with NTDs take 5mg (5000 micrograms) of folic acid daily in order to help prevent NTDs in the unborn child. The 5mg folic acid supplements are only available on prescription from your doctor.
Diabetes UK has obtained a consensus of expert opinion from healthcare professionals and recommend that all women with diabetes should also take the 5mg dose of folic acid daily. This is because there is evidence that shows women with diabetes are at a significantly increased risk of having a baby with NTDs.(1,2) In 1991 the MRC Vitamin Study Research Group published the results of a study into the prevention of NTDs(3), and in response to that, an Expert Advisory Group was formed by the Department of Health to specifically consider the role of folic acid in the prevention of NTDs.(4) The recommendation of the Advisory Group for women who have spina bifida or who have previously had a child with NTDs, was that they should take a daily supplement of 5mg folic acid. There is no evidence to suggest that this dosage of folic acid has any adverse effects on the woman or the foetus.
There is a concern that high intakes of folic acid might cause the onset of nerve damage in women with undiagnosed Vitamin B12 deficiency. However, careful monitoring can eliminate this problem. Women who have epilepsy should talk to their doctor before taking folic acid supplements.
Of critical importance is pre-conception care for women with diabetes, and folic acid supplements, and this should be taken before conception and continue for the first 12 weeks of pregnancy.
References
- Pre-conception care of diabetes, congenital malformations, and spontaneous abortions. 1996. Diabetes Care, 19(5): 514-541
- Diabetes mellitus during pregnancy and the risks for specific birth defects: a population-based case-control study. 1990. Paediatrics, 85: 1-9
- Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. 1991. The Lancet, 338: 131-137
- Folic acid and the prevention of neural tube defects : report from an Expert Advisory Group. 1992. London: Department of Health
Last reviewed June 2005