According to the latest research from the U.S. the number of pregnant women with diabetes has more than doubled in the last six years.
In a large health survey of expectant mothers, doctors examined 175,249 women who gave birth in 11 hospitals between 1999 and 2005 and they found a significant increase in pre-pregnancy diabetes across all age, racial and ethnic groups.
The revelation has caused concern because the rise will lead to a greater risk of miscarriages, stillbirths and babies with serious birth defects and also because children born to diabetic women are more likely to develop diabetes themselves.
Experts suggest the rise reflects the sharp increase in type 2 diabetes, which is driven by soaring rates of obesity - the study also found that cases of gestational diabetes, a temporary condition which usually abates after childbirth, remained steady at 8%.
In the 13 to 19 age group, diabetes rose fivefold, and doubled among women aged 20 to 39, while women aged 40 and older showed a 40% increase in diabetes over the same time period.
Experts say an increase in type 2 diabetes can be seen in the U.S. and worldwide and whereas it used to be considered adult-onset diabetes, with diagnosis in the 40s, it is now appearing in children as young as age 10.
Recent research has shown that women with diabetes are seven times more likely to have a stillborn baby than healthy women, while those with type 2 diabetes are twice as likely to miscarry and five times more likely to have a baby with birth defects compared with women with type 1 diabetes.
The researchers say expectant mothers who do not control their diabetes face high-risk pregnancies.
They recommend that women who are diabetic seek medical help at least three months before they plan to have a baby so doctors can help them control their blood sugar and increase their intake of folic acid.
Lead author Jean Lawrence, a research scientist with Kaiser Permanente Southern California says there are things women can do before they become pregnant that will increase the likelihood of them having a healthy baby, including controlling blood sugar levels with an insulin pump, and maintaining a healthy diet and exercise routine.
Overweight women are encouraged to shed some pounds before getting pregnant.
According to the American Diabetes Association about 15 million people in the United States are diagnosed with diabetes, and 1.5 million new cases were diagnosed in people age 20 and older in 2005.
The study appears in the journal Diabetes Care.