Pregnant women with type 1 or type 2 diabetes are at a greater risk of adverse outcomes in pregnancy, such as miscarriage or large babies and preterm birth. Being pregnant can trigger diabetes in women with impaired glucose tolerance or can accelerate the development of diabetic complications in women who are already diabetic. Women who have gestational diabetes are at risk of developing diabetes later in life. This means that management is important for women with diabetes and also for women with impaired glucose tolerance or previously diagnosed gestational diabetes.
It is usually recommended that women with diabetes have good control of their blood sugar levels before they become pregnant, and guidelines suggest insulin be used where additional control is required. Women with type 1 diabetes are likely to have used insulin for some time. Women with type 2 diabetes may have good control of their diabetes with diet and lifestyle changes alone, or with the use of an oral anti-diabetic agent. Women with diabetes using an oral anti-diabetic agent are usually advised to change to insulin before pregnancy for better blood sugar control and because there is little known about the effects of oral anti-diabetic agents in early pregnancy. Oral agents are, however, more convenient and acceptable than insulin injections and do not require the intensive education that is needed with insulin injections.
This review sought to investigate the effect of oral anti-diabetic agents in women with pre-existing diabetes mellitus, impaired glucose tolerance, or previous gestational diabetes, or women with diabetes mellitus planning a pregnancy on maternal and infant health.
We were not able to include any of the studies identified by the Cochrane literature search in the review. One trial has not been published in full yet and is awaiting assessment. An additional trial is ongoing. Further research is required comparing the effects of the oral anti-diabetic agents with insulin and dietary and lifestyle advice in these women, in order to determine effects on the health of the mother and her baby, the level of blood sugar control achieved, women's views on the treatment, and long-term outcomes for the woman and child.