Maternal diabetes mellitus (types 1 and 2) is the most chronic prevalent me
dical condition affecting the pregnant population and is associated with a
less satisfactory pregnancy outcome for both mother and infant when compare
d with the non-diabetic population. Most reports have focused on women with
type 1 disease, type 2 disease being perceived as a less serious condition
. However, type 2 disease is far more common (and is increasing) in some ar
eas of the UK, especially where there is a high proportion of women from th
e Indian subcontinent. This paper shows that pregnancy complicated by type
2 diabetes mellitus is a high-risk state, with miscarriage and congenital m
alformations almost twice that seen in type 1 disease. These adverse outcom
es are contributed to by poor attendance for pre-pregnancy care, later book
ing for antenatal clinic and poor glycaemic control at booking. Offspring o
f pregnancies complicated by type 2 diabetes are more likely to be delivere
d before 37 weeks gestation and be large in size for gestational age. We mu
st dispel the myth, in women of childbearing age and in their healthcare pr
oviders, that diabetes treated with diet and/or tablets (type 2) is a less
serious problem than type 1 disease.