Abstract

Pregnancy with type 1 diabetes is considered to have a high incidence of pre-eclampsia (PET), but these women often have hypertension or proteinuria at <20 weeks gestation confusing the diagnosis.

The DAPIT study randomised 762 women with type 1 diabetes to vitamin C and E supplementation, to investigate if this reduced the incidence of PET. As no significant effect was found both groups were combined allowing analysis of hypertensive disorders in a large cohort.

Before pregnancy, previous hypertension was noted in 25% of women who developed PET, 13% of women who developed gestational hypertension (GHT) and 10% who had neither (p <0.001).

By 20 weeks 32% of women had hypertension, proteinuria or both and 29% were subsequently classified as having PET in contrast to only 12% who had no problem <20 weeks (p <0.0001). However, of those who were classified as having PET, 56% had evidence of hypertensive or renal impairment <20 weeks compared to 24% who had no subsequent hypertensive problem (p <0.0001).

While liver enzymes and serum urate were significantly elevated in the PET group the results were similar whether or not there was a problem <20 weeks. However thrombocytopenia occurred more in the PET group who only had a problem >20 weeks. Birthweight <5^th and <90^th centile was significantly greater in the PET group, but significantly more in those with a problem<20 weeks.

In conclusion not all diabetic women classified as having PET appear to have the condition but further markers are required to differentiate.