Suboptimal blood pressure control early in pregnancy plus
compromised renal function combine to increase risk of preterm birth
in diabetic women, a Seattle team reports.

Diabetic nephropathy is a complication in an estimated 5% to 10% of
pregnancies. Dr. Darcy Carr and colleagues at the University of
Washington investigated the further impact hypertension has on
pregnancy outcome in these women.

They conducted a retrospective cohort study of pregnancies
complicated by diabetic nephropathy. There were 21 women with mean
arterial pressures of 100 mmHg or higher (Above Target group) and 22
women with mean arterial pressures below 100 mmHg (Below Target
group). Blood pressures were recorded before 20 weeks gestation.

Maternal age was essentially the same in both groups, ranging from
27 to 29 years. Duration of diabetes ranged from 16 to 17.5 years on
average in both groups and glycosylated hemoglobin A1c was 8.0%.

Mean proteinuria levels in the Above Target group were 4.69 g/24
hours and 1.65 g/24 hours in the Below Target group. Serum
creatinine levels were 1.23 mg/dL in the Above Target group and 0.85
mg/dL in the Below Target group.

Delivery before 32 weeks gestation occurred in 38.1% of women in the
Above Target group but in only 4.6% of those with mean arterial
pressures Below Target early in pregnancy.

Increased risk of preterm delivery remained even after adjusting for
duration of diabetes and glucose control.

"We have shown that an alarming number of women with diabetic
nephropathy enter pregnancy care with suboptimal control of
hypertension as defined by the American Diabetes Association and the
Seventh Report of the Joint National Committee," the investigators
write in the May issue of the American Journal of Hypertension.

"Reproductive age women with diabetes should be managed as if they
might become pregnant, which should include aggressive control of
blood glucose and hypertension to achieve the ADA and JNC7
standards," Dr. Carr and colleagues advise.

Am J Hypertens 2006;19:513-519