Pre-Pregnancy Diabetes Rates Have Doubled

MONDAY, April 28 (HealthDay News) -- The number of women starting their pregnancies with type 1 or type 2 diabetes has doubled since 1999, but rates of gestational diabetes have stayed the same, new research finds.

In some age groups, the results were even worse. Researchers from Kaiser Permanente found that the number of teenagers who had diabetes before birth jumped fivefold.

"It's important to recognize with the increase in overweight and obesity, more women than ever will be entering their reproductive years with diabetes," said study author Jean Lawrence, a research scientist at Kaiser Permanente Bellflower Medical Center, in Bellflower, Calif.

And, she added, "having diabetes during pregnancy increases the risk of miscarriage early in pregnancy and the risk of stillbirth later in pregnancy. It also increases the chances of having a baby with birth defects, and it may result in larger babies and more difficult deliveries."

Results of the study are published in the May issue of Diabetes Care.

Past research has focused on the number of women who develop diabetes during pregnancy, which is called gestational diabetes, and generally disappears after the baby is born.

The new study, which included 175,249 women who gave birth from 1999 to 2005, also included women with type 1 and type 2 diabetes. All of the women in the study were treated at one of 11 Kaiser Permanente hospitals in southern California. Fifty-two percent of the women were Hispanic, 26 percent were white, 11 percent were Asian/Pacific Islanders, and 10 percent were black, according to the study.

Preexisting diabetes -- type 1 or type 2 -- was found in 1.3 percent of all pregnancies. In 1999, the rate of preexisting diabetes was 0.81 per 100 births; by 2005, that number had jumped to 1.82 per 100 births.

But, during that six-year period, gestational diabetes rates remained nearly unchanged. In 1999, 7.5 women per 100 births had gestational diabetes; in 2005, it was 7.4 women per 100 births.

What did change during the study period was the proportion of preexisting diabetes compared to gestational diabetes. In 1999, of all pregnancies affected by diabetes, 10 percent were due to preexisting diabetes, while 90 percent were due to gestational diabetes. In 2005, 21 percent of women had preexisting diabetes, compared to 79 percent with gestational diabetes, according to the study.