SATURDAY, June 26 (HealthDay News) -- Taking vitamin C and E
supplements will not lower the risk of the blood pressure disorder
known as preeclampsia in pregnant women with type 1 diabetes, a new
Women with diabetes are at high risk for preeclampsia (a sudden
increase in the mother's blood pressure after the 20th week of
pregnancy), and prior research has suggested that because type 1
diabetes is associated with increased oxidative stress and lower
levels of antioxidants in the body, taking antioxidant vitamins
The British study included 762 pregnant women with type 1
diabetes. They were randomly assigned to take 1000 milligrams of
vitamin C and 400 international units (IU) vitamin E (379 women) or
placebo (383 women) daily from between eight and 22 weeks of
gestation and delivery.
The rate of preeclampsia was 15 percent in the vitamins group
and 19 percent in the placebo group. However, taking vitamins
seemed to significantly lower the risk of preeclampsia in women
with low antioxidant status at the start of the study and appeared
to reduce the risk of having a low birthweight baby (6 percent vs.
10 percent). Also, fewer women in the vitamin C group had preterm
Researchers from Queen's University Belfast said the findings
suggest that dietary "intervention rich in various antioxidants
might have benefits that cannot be replicated by individual
supplements. Alternatively, prescription of antioxidant vitamins at
8-22 weeks' gestation might be too late to affect the pathological
process for most patients with diabetes."
"In principle, the notion that oxidative stress is implicated in pathogenesis of pre-eclampsia remains plausible, but the benefit of vitamin supplementation might be limited to women with vitamin depletion; however, this idea needs confirmation," they concluded.
However, in a commentary, Dr. Baha M. Sibai of the University of
Cincinnati, noted that the study participants who took a placebo
were more likely to have had a prior history of preeclampsia or
chronic high blood pressure than women who took the vitamins.
Because the researchers did not adjust for this and other factors
"in women with low antioxidant status, the conclusions for this
group might not be valid," he wrote.
Sibai also noted that because preeclampsia can have many causes,
"any single intervention is unlikely to be effective in
The study appears online in
The Lancet and is also slated for presentation Saturday at
the American Diabetes Association meeting in Orlando.
The U.S. National Institute of Child Health and Human
Development has more about